A case of dedifferentiated carcinoma occurring in adenoid cystic carcinoma of the submandibular gland with multiple metastasis

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology

Author(s): Kazutaka Kimura, Yuichi Ohnishi, Tomoko Fujii, Kenji Kakudo, Masaki Akane

Abstract

Dedifferentiated adenoid cystic carcinoma (ACC) are rare variant of ACC characterized histologically by two components: conventional low-grade ACC and high-grade "dedifferentiated" carcinoma. We report a case of dedifferentiated carcinoma occurring in ACC of the submandibular gland with multiple distant metastasis. The patient, a 39-year-old woman was referred to our hospital because of submandibular gland carcinoma with multiple distant metastasis. We underwent a right neck dissection and right submandibular gland tumor resection. Histologically, the low-grade ACC merged gradually into an extensive dedifferentiated component that was composed of solid sheets and cords of anaplastic tumor cells with focal gland formation, and distant metastasis contained dedifferentiated component. We planned the treatment of postoperative radiotherapy and chemotherapy. But the patient is a Chinese living in Japan, so she wish to receive the treatment of post-operative in China and she returned to China.

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Prevalence of oral mucosal disorders during pregnancy: A systematic review and meta‐analysis

Abstract

Objective

To assess the prevalence of oral mucosal disorders during pregnancy.

Methods

Observational studies were selected by two reviewers in a two‐phase process. Search strategies were applied at CINAHL, LILACS, LIVIVO, PubMed, Scopus, Web of Science, Google Scholar, Open Grey, and ProQuest. The risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated by the software R Statistics version 3.5.1 (The R Foundation, Vienna, Austria). Confidence in cumulative evidence was assessed by using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

Results

Fifteen studies met the eligibility criteria and were selected for qualitative synthesis and meta‐analysis, of which 5,935 participants were enrolled. The overall prevalence of oral mucosal disorders was 11.8%. Gingival hyperplasia (17.1%), morsicatio buccarum (10%), oral candidiasis (4.4%), pyogenic granuloma (3%), and benign migratory glossitis (2.8%) were the most prevalent lesions. The overall risk of bias was considered moderate and the quality of evidence was very low.

Conclusion

Disorders of the oral mucosa were present in approximately 1 out of 10 pregnant women. Gingival hyperplasia was the most prevalent lesion. Further studies should apply homogeneous methodology to improve the quality of evidence.

This article is protected by copyright. All rights reserved.

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A case of dedifferentiated carcinoma occurring in adenoid cystic carcinoma of the submandibular gland with multiple metastasis

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology

Author(s): Kazutaka Kimura, Yuichi Ohnishi, Tomoko Fujii, Kenji Kakudo, Masaki Akane

Abstract

Dedifferentiated adenoid cystic carcinoma (ACC) are rare variant of ACC characterized histologically by two components: conventional low-grade ACC and high-grade "dedifferentiated" carcinoma. We report a case of dedifferentiated carcinoma occurring in ACC of the submandibular gland with multiple distant metastasis. The patient, a 39-year-old woman was referred to our hospital because of submandibular gland carcinoma with multiple distant metastasis. We underwent a right neck dissection and right submandibular gland tumor resection. Histologically, the low-grade ACC merged gradually into an extensive dedifferentiated component that was composed of solid sheets and cords of anaplastic tumor cells with focal gland formation, and distant metastasis contained dedifferentiated component. We planned the treatment of postoperative radiotherapy and chemotherapy. But the patient is a Chinese living in Japan, so she wish to receive the treatment of post-operative in China and she returned to China.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2FLOg1E

Prevalence of oral mucosal disorders during pregnancy: A systematic review and meta‐analysis

Abstract

Objective

To assess the prevalence of oral mucosal disorders during pregnancy.

Methods

Observational studies were selected by two reviewers in a two‐phase process. Search strategies were applied at CINAHL, LILACS, LIVIVO, PubMed, Scopus, Web of Science, Google Scholar, Open Grey, and ProQuest. The risk of bias was assessed using the Joanna Briggs Institute's Critical Appraisal Checklist for Studies Reporting Prevalence Data. Synthesis of results was calculated by the software R Statistics version 3.5.1 (The R Foundation, Vienna, Austria). Confidence in cumulative evidence was assessed by using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

Results

Fifteen studies met the eligibility criteria and were selected for qualitative synthesis and meta‐analysis, of which 5,935 participants were enrolled. The overall prevalence of oral mucosal disorders was 11.8%. Gingival hyperplasia (17.1%), morsicatio buccarum (10%), oral candidiasis (4.4%), pyogenic granuloma (3%), and benign migratory glossitis (2.8%) were the most prevalent lesions. The overall risk of bias was considered moderate and the quality of evidence was very low.

Conclusion

Disorders of the oral mucosa were present in approximately 1 out of 10 pregnant women. Gingival hyperplasia was the most prevalent lesion. Further studies should apply homogeneous methodology to improve the quality of evidence.

This article is protected by copyright. All rights reserved.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2HtwLod

Evidence for age-related cochlear synaptopathy in humans unconnected to speech-in-noise intelligibility deficits

Publication date: Available online 24 January 2019

Source: Hearing Research

Author(s): Peter T. Johannesen, Byanka C. Buzo, Enrique A. Lopez-Poveda

Abstract

Cochlear synaptopathy (or the loss of primary auditory synapses) remains a subclinical condition of uncertain prevalence. Here, we investigate whether it affects humans and whether it contributes to suprathreshold speech-in-noise intelligibility deficits. For 94 human listeners with normal audiometry (aged 12-68 years; 64 women), we measured click-evoked auditory brainstem responses (ABRs), self-reported lifetime noise exposure, and speech reception thresholds for sentences (at 65 dB SPL) and words (at 50, 65 and 80 dB SPL) in steady-state and fluctuating maskers. Based on animal research, we assumed that the shallower the rate of growth of ABR wave-I amplitude versus level function, the higher the risk of suffering from synaptopathy. We found that wave-I growth rates decreased with increasing age but not with increasing noise exposure. Speech reception thresholds in noise were not correlated with wave-I growth rates and mean speech reception thresholds were not statistically different for two subgroups of participants (N=14) with matched audiograms (up to 12 kHz) but different wave-I growth rates. Altogether, the data are consistent with the existence of age-related but not noise-related synaptopathy. In addition, the data dispute the notion that synaptopathy contributes to suprathreshold speech-in-noise intelligibility deficits.

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Principles of artificial ventilation

Publication date: Available online 23 January 2019

Source: Anaesthesia & Intensive Care Medicine

Author(s): Ben Brown, Justin Roberts

Abstract

The application of intermittent positive pressure ventilation (IPPV) during the 1952 Copenhagen polio epidemic led to the development of the world's first intensive care unit. The requirement for ventilatory support is the most common indication for intensive therapy unit (ITU) admission and is a defining feature of the specialty. Ventilator technology continues to develop and there are many ways to deliver IPPV. The variety of modes of ventilation is increasingly complex and expanding, without evidence that any one mode is associated with improved outcome. Ventilatory support is part of the treatment for a range of conditions including acute respiratory failure, raised intracranial pressure (ICP) and circulatory shock. Ventilator-associated lung injury is reduced by using low tidal volumes and limiting plateau airway pressure to less than 30 cmH₂O. Prolonged artificial ventilation has an associated morbidity and mortality and thus should be reviewed by an expert clinician on a daily basis. Weaning aims to identify those patients who will be able to breathe spontaneously. Protocols exist to facilitate timely extubation without the need for re-intubation.

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Feasibility of direct promontory stimulation by bone conduction: a preliminary study of frequency-response characteristics in cats

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Yu-Xuan Shi, Liu-Jie Ren, Lin Yang, Tian-Yu Zhang, You-Zhou Xie, Pei-Dong Dai

Abstract

Background

As an alternative pathway to air conduction, bone conduction is a multipathway process that transmits sound energy to the inner ear through the skull in general. Based on this mechanism, bone conduction devices (BCDs) have been used widely in the rehabilitation of hearing loss. Although great efforts have been devoted to improving BCDs, drawbacks still exist in most categories of BCDs due to the complicated process of bone conduction. We hypothesized that if a bone conduction transducer was placed on the cochlea to stimulate it directly, the attenuation would be minimized, and the frequency dependency would be different from that of the vibratory response induced by traditional BCDs. This study aimed to explore the feasibility of direct promontory stimulation and to investigate its frequency-response characteristics.

Methods

Measurements were conducted in twelve cat ears. To stimulate the promontory directly, the floating mass transducer (FMT) of the Vibrant Soundbridge^© (VSB) implant was glued to the promontory coupled with an oval window (OW) coupler. Auditory brainstem response (ABR) and laser Doppler vibrometry (LDV) measurements were used to evaluate the auditory response induced by the FMT. In both measurements, the FMT was driven by direct voltage stimuli.

Results

ABR waves could be induced under direct promontory stimulation by the FMT. In the frequency range of 1-12 kHz, the variation in the voltage threshold level were limited to 16 dB SPL with a maximum of 0.2 V at 1 kHz and a minimum of 0.04 V at 10 kHz. In the LDV measurements and the relative motion of the round window membrane (RWM) and the promontory were used to evaluate the cochlear response. The LDV results indicated a weak frequency dependency from 1-12 kHz.

Conclusion

Different from traditional stimulation via transcranial bone conduction, direct promontory stimulation is a new method in which a small bone conduction transducer stimulates the cochlear shell directly. The current experimental data demonstrate that it is feasible to generate sensations through bone conduction by stimulating the cochlea directly. Furthermore, the cochlear response induced by this type of stimulus in cats was weakly frequency dependent at frequencies ranging from 1-12 kHz. This study may provide a basis for the design of new transducers that can perform well over a wide range of frequencies.

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Comparison of the Effect of Topical Use of Nigella Sativa Oil and Diclofenac Gel on Osteoarthritis Pain in Older People: A Randomized, Double-blind, Clinical Trial

Publication date: Available online 23 January 2019

Source: Journal of Herbal Medicine

Author(s): Fatemeh Azizi, Fereshteh Ghorat, Mohammad Hassan Rakhshani, Mostafa Rad

Abstract

Osteoarthritis is one of the most common diseases in the elderly. Herbal remedies create pain relief with appropriate clinical effects and less toxicity. We aimed to investigate the effect of Nigella sativa oil compared with diclofenac gel on the reduction of osteoarthritis pain in older people. This was a double-blind clinical trial. Samples were 52 men and women aged 60-80 years. They were selected using a convenience method, that were randomly assigned into Nigella sativa oil and diclofenac gel groups. The topical application of Nigella sativa oil and diclofenac gel was performed twice a day in the morning and night for 21 days. The Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire was used for data collection about pain before the use of drugs, in the tenth day and the twenty-first day of the intervention. Paired t-test showed that both interventions improved pain in the subjects (P < 0.05). However, t-test and Mann-Whitney U test showed that pain on the 21 st day after the intervention was significantly lower in the Nigella sativa oil group compared with that of the diclofenac gel group (P = 0.04). Also, the results of this study showed that Nigella sativa oil had a better pain relief effect than diclofenac gel. The mean pain scores in the Nigella sativa oil and diclofenac gel groups before the intervention were 75 ± 16.29 and 57.66 ± 19.66, respectively. Also, pain on the 21 st day after the intervention was 38.88 ± 17.84 and 50.33 ± 20.38, respectively. In general, Nigella sativa oil was more effective than diclofenac gel on osteoarthritis pain.

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Principles of artificial ventilation

Publication date: Available online 23 January 2019

Source: Anaesthesia & Intensive Care Medicine

Author(s): Ben Brown, Justin Roberts

Abstract

The application of intermittent positive pressure ventilation (IPPV) during the 1952 Copenhagen polio epidemic led to the development of the world's first intensive care unit. The requirement for ventilatory support is the most common indication for intensive therapy unit (ITU) admission and is a defining feature of the specialty. Ventilator technology continues to develop and there are many ways to deliver IPPV. The variety of modes of ventilation is increasingly complex and expanding, without evidence that any one mode is associated with improved outcome. Ventilatory support is part of the treatment for a range of conditions including acute respiratory failure, raised intracranial pressure (ICP) and circulatory shock. Ventilator-associated lung injury is reduced by using low tidal volumes and limiting plateau airway pressure to less than 30 cmH₂O. Prolonged artificial ventilation has an associated morbidity and mortality and thus should be reviewed by an expert clinician on a daily basis. Weaning aims to identify those patients who will be able to breathe spontaneously. Protocols exist to facilitate timely extubation without the need for re-intubation.

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Establishment and verification of a mouse model of nasal wound healing

Objectives

Poor wound healing as reflected by the development of synechia and osteitis after endoscopic sinus surgery may trigger disease recurrence. Animal models provide insights into the pathogenesis of poor wound healing and may aid in the development of new therapeutics. Here, we established a mouse model of nasal wound healing and confirmed its utility.

Study Design

Animal study.

Methods

Unilateral intranasal wounds were induced using a small interdental brush in 6‐week‐old C57BL/6 mice. Forty‐five mice were divided into three groups (each n = 15): one control and two experimental groups (intranasal vs. intraperitoneal dexamethasone). Mice were sacrificed on days 2, 14, and 28 after injury (each n = 5). Serial changes in nasal wound histopathology were described, and intergroup differences were analyzed.

Results

On day 2, mucosal detachment, hemorrhage, and exudate were observed. On day 14, synechiae featuring neo‐osteogenesis (bone lacunae, osteoblasts, and multinucleated osteoclasts) between the septum and the maxilloturbinate were prominent, followed by wound maturation on day 28: fewer lacunae and smaller osteoblasts. Macrophages were evident only on day 2, and lymphocytes were predominant on day 28. The amount of exudate on day 2 and the synechial area on day 28 were significantly reduced in mice that received dexamethasone systemically compared with control mice, with similar trends in those treated intranasally.

Conclusion

Our mouse model of nasal wound healing was characterized by the development of bony synechia and neo‐osteogenesis, not soft‐tissue synechia. The model may be useful in the assessment of novel therapeutics to prevent those wounds.

Level of Evidence

NA. Laryngoscope, 2019

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Establishment and verification of a mouse model of nasal wound healing

Objectives

Poor wound healing as reflected by the development of synechia and osteitis after endoscopic sinus surgery may trigger disease recurrence. Animal models provide insights into the pathogenesis of poor wound healing and may aid in the development of new therapeutics. Here, we established a mouse model of nasal wound healing and confirmed its utility.

Study Design

Animal study.

Methods

Unilateral intranasal wounds were induced using a small interdental brush in 6‐week‐old C57BL/6 mice. Forty‐five mice were divided into three groups (each n = 15): one control and two experimental groups (intranasal vs. intraperitoneal dexamethasone). Mice were sacrificed on days 2, 14, and 28 after injury (each n = 5). Serial changes in nasal wound histopathology were described, and intergroup differences were analyzed.

Results

On day 2, mucosal detachment, hemorrhage, and exudate were observed. On day 14, synechiae featuring neo‐osteogenesis (bone lacunae, osteoblasts, and multinucleated osteoclasts) between the septum and the maxilloturbinate were prominent, followed by wound maturation on day 28: fewer lacunae and smaller osteoblasts. Macrophages were evident only on day 2, and lymphocytes were predominant on day 28. The amount of exudate on day 2 and the synechial area on day 28 were significantly reduced in mice that received dexamethasone systemically compared with control mice, with similar trends in those treated intranasally.

Conclusion

Our mouse model of nasal wound healing was characterized by the development of bony synechia and neo‐osteogenesis, not soft‐tissue synechia. The model may be useful in the assessment of novel therapeutics to prevent those wounds.

Level of Evidence

NA. Laryngoscope, 2019

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Taste disorders are partly genetically determined: Role of the TAS2R38 gene, a pilot study

Objectives/Hypothesis

Taste sensitivity varies greatly among individuals influencing eating behavior and health, consequently the disorders of this sense can affect the quality of life. The ability to perceive the bitter of thiourea compounds, such as phenylthiocarbamide (PTC), has been largely reported as a marker of the general taste sensitivity, food preferences, and health. PTC sensitivity is mediated by the TAS2R38 receptor and its genetic common variants. We study the role of the TAS2R38 receptor in taste disorders with the aim of understanding if these can be genetically determined.

Study Design

Prospective cohort study.

Methods

Differences in the PTC responsiveness between the patients cohort and healthy controls were assessed. All subjects received standardized tests for smell and taste function and were genotyped for the TAS2R38 gene.

Results

PAV/PAV homozygous patients gave high PTC ratings, whereas PAV/AVI genotypes reported lower values, which are similar to those determined in AVI/AVI or rare genotypes. In addition, the patients cohort did not meet the Hardy‐Weinberg equilibrium at the TAS2R38 locus, showing a very low frequency of subjects carrying the PAV/AVI diplotype. Independently, in healthy controls who were in equilibrium at the locus, PAV/PAV homozygous and heterozygous rated PTC bitterness higher compared to AVI/AVI or rare genotypes.

Conclusions

Our findings, by showing that an only taster haplotype (PAV) is not sufficient to evoke high responses of TAS2R38 receptor in patients with taste disorders, suggest that the genetic constitution may represent a risk factor for the development of taste disorders.

Level of Evidence

2c Laryngoscope, 2019

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Evidence for age-related cochlear synaptopathy in humans unconnected to speech-in-noise intelligibility deficits

Publication date: Available online 24 January 2019

Source: Hearing Research

Author(s): Peter T. Johannesen, Byanka C. Buzo, Enrique A. Lopez-Poveda

Abstract

Cochlear synaptopathy (or the loss of primary auditory synapses) remains a subclinical condition of uncertain prevalence. Here, we investigate whether it affects humans and whether it contributes to suprathreshold speech-in-noise intelligibility deficits. For 94 human listeners with normal audiometry (aged 12-68 years; 64 women), we measured click-evoked auditory brainstem responses (ABRs), self-reported lifetime noise exposure, and speech reception thresholds for sentences (at 65 dB SPL) and words (at 50, 65 and 80 dB SPL) in steady-state and fluctuating maskers. Based on animal research, we assumed that the shallower the rate of growth of ABR wave-I amplitude versus level function, the higher the risk of suffering from synaptopathy. We found that wave-I growth rates decreased with increasing age but not with increasing noise exposure. Speech reception thresholds in noise were not correlated with wave-I growth rates and mean speech reception thresholds were not statistically different for two subgroups of participants (N=14) with matched audiograms (up to 12 kHz) but different wave-I growth rates. Altogether, the data are consistent with the existence of age-related but not noise-related synaptopathy. In addition, the data dispute the notion that synaptopathy contributes to suprathreshold speech-in-noise intelligibility deficits.

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Distortion product otoacoustic emissions: sensitive measures of tympanic -membrane perforation and healing processes in a gerbil model

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Wei Dong, Glenna Stomackin, Xiaohui Lin, Glen K. Martin, Timothy T. Jung

Abstract:

Distortion product otoacoustic emissions (DPOAEs) evoked by two pure tones carry information about the mechanisms that generate and shape them. Thus, DPOAEs hold promise for providing powerful noninvasive diagnostic details of cochlear operations, middle ear (ME) transmission, and impairments. DPOAEs are sensitive to ME function because they are influenced by ME transmission twice, i.e., by the inward-going primary tones in the forward direction and the outward traveling DPOAEs in the reverse direction. However, the effects of ME injuries on DPOAEs have not been systematically characterized. The current study focused on exploring the utility of DPOAEs for examining ME function by methodically characterizing DPOAEs and ME transmission under pathological ME conditions, specifically under conditions of tympanic- membrane (TM) perforation and spontaneous healing.

Results indicated that DPOAEs were measurable with TM perforations up to ∼50%, and DPOAE reductions increased with increasing size of the TM perforation. DPOAE reductions were approximately flat across test frequencies when the TM was perforated about 10% (<1/8 of pars tensa) or less. However, with perforations greater than 10%, DPOAEs decreased further with a low-pass filter shape, with ∼30 dB loss at frequencies below 10 kHz and a quick downward sloping pattern at higher frequencies. The reduction pattern of DPOAEs across frequencies was similar to but much greater than, the directly measured ME pressure gain in the forward direction, which suggested that reduction in the DPOAE was a summation of losses of ME ear transmission in both the forward and reverse directions. Following 50% TM perforations, DPOAEs recovered over a 4-week spontaneously healing interval, and these recoveries were confirmed by improvements in auditory brainstem response (ABR) thresholds. However, up to 4-week post-perforation, DPOAEs never fully recovered to the levels obtained with normal intact TM, consistent with the incomplete recovery of ABR thresholds and ME transmission, especially at high-frequency regions, which could be explained by an irregularly dense and thickened healed TM.

Since TM perforations in patients are commonly caused by either trauma or infection, the present results contribute towards providing insight into understanding ME transmission under pathological conditions as well as promoting the application of DPOAEs in the evaluation and diagnosis of deficits in the ME-transmission system.

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Sound localization in the lizard using internally coupled ears: a finite-element approach

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Pieter Livens, Pieter G.G. Muyshondt, Joris J.J. Dirckx

Abstract

A number of interesting differences become apparent when comparing the hearing systems of terrestrial vertebrates, especially between mammals and non-mammals. Almost all non-mammals possess only a single ossicle, enabling impedance matching and hearing below 10 kHz. The middle ear (ME) evolved as a chain of three ossicles in mammals, enabling sound transmission up to higher frequencies than in similar-sized non-mammals. The relatively low-frequency hearing in non-mammals is associated with audible wavelengths that are significantly larger than the head. Therefore, it is unlikely that localization of the sound source can be obtained by using external cues between the ears (intensity and time difference between both sides), especially when compared to similarly sized mammals. The heads of many non-mammals contain large air-filled cavities, which acoustically couple both MEs. This article studies acoustic responses and sound-source localization capabilities of the coupled MEs of the brown anole (Anolis sagrei), using finite-element modeling. Based on high-resolution μCT data, 3D finite-element models of the ME and interaural cavity were constructed. The parameter values in the ME model were determined such that the response of the isolated ME matches experimental data of literature and the velocity ratio between the tympanic membrane (apex) and footplate reflects the anatomical arrangement of the columellar lever in the anole. It was found from simulation of the coupled ME model that the interaural connection amplifies intensity differences between both sides and thus enhances the capability of sound-source localization. In addition, the interaural canal doubles the phase differences of the incident external sound waves between the eardrums. In isolated ears, generating such phase differences would require head sizes twice as large. Effects of the inner-ear loading on the sound-source localization of the coupled MEs were investigated as well. The inner-ear load lowered the peak velocity ratios between the ears, but created broader plateaus of useful directionality, indicating that inner-ear loading not only influences sound perception but also sound localization in internally connected ears.

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Sound localization in the lizard using internally coupled ears: a finite-element approach

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Pieter Livens, Pieter G.G. Muyshondt, Joris J.J. Dirckx

Abstract

A number of interesting differences become apparent when comparing the hearing systems of terrestrial vertebrates, especially between mammals and non-mammals. Almost all non-mammals possess only a single ossicle, enabling impedance matching and hearing below 10 kHz. The middle ear (ME) evolved as a chain of three ossicles in mammals, enabling sound transmission up to higher frequencies than in similar-sized non-mammals. The relatively low-frequency hearing in non-mammals is associated with audible wavelengths that are significantly larger than the head. Therefore, it is unlikely that localization of the sound source can be obtained by using external cues between the ears (intensity and time difference between both sides), especially when compared to similarly sized mammals. The heads of many non-mammals contain large air-filled cavities, which acoustically couple both MEs. This article studies acoustic responses and sound-source localization capabilities of the coupled MEs of the brown anole (Anolis sagrei), using finite-element modeling. Based on high-resolution μCT data, 3D finite-element models of the ME and interaural cavity were constructed. The parameter values in the ME model were determined such that the response of the isolated ME matches experimental data of literature and the velocity ratio between the tympanic membrane (apex) and footplate reflects the anatomical arrangement of the columellar lever in the anole. It was found from simulation of the coupled ME model that the interaural connection amplifies intensity differences between both sides and thus enhances the capability of sound-source localization. In addition, the interaural canal doubles the phase differences of the incident external sound waves between the eardrums. In isolated ears, generating such phase differences would require head sizes twice as large. Effects of the inner-ear loading on the sound-source localization of the coupled MEs were investigated as well. The inner-ear load lowered the peak velocity ratios between the ears, but created broader plateaus of useful directionality, indicating that inner-ear loading not only influences sound perception but also sound localization in internally connected ears.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2RJQ9lG

Distortion product otoacoustic emissions: sensitive measures of tympanic -membrane perforation and healing processes in a gerbil model

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Wei Dong, Glenna Stomackin, Xiaohui Lin, Glen K. Martin, Timothy T. Jung

Abstract:

Distortion product otoacoustic emissions (DPOAEs) evoked by two pure tones carry information about the mechanisms that generate and shape them. Thus, DPOAEs hold promise for providing powerful noninvasive diagnostic details of cochlear operations, middle ear (ME) transmission, and impairments. DPOAEs are sensitive to ME function because they are influenced by ME transmission twice, i.e., by the inward-going primary tones in the forward direction and the outward traveling DPOAEs in the reverse direction. However, the effects of ME injuries on DPOAEs have not been systematically characterized. The current study focused on exploring the utility of DPOAEs for examining ME function by methodically characterizing DPOAEs and ME transmission under pathological ME conditions, specifically under conditions of tympanic- membrane (TM) perforation and spontaneous healing.

Results indicated that DPOAEs were measurable with TM perforations up to ∼50%, and DPOAE reductions increased with increasing size of the TM perforation. DPOAE reductions were approximately flat across test frequencies when the TM was perforated about 10% (<1/8 of pars tensa) or less. However, with perforations greater than 10%, DPOAEs decreased further with a low-pass filter shape, with ∼30 dB loss at frequencies below 10 kHz and a quick downward sloping pattern at higher frequencies. The reduction pattern of DPOAEs across frequencies was similar to but much greater than, the directly measured ME pressure gain in the forward direction, which suggested that reduction in the DPOAE was a summation of losses of ME ear transmission in both the forward and reverse directions. Following 50% TM perforations, DPOAEs recovered over a 4-week spontaneously healing interval, and these recoveries were confirmed by improvements in auditory brainstem response (ABR) thresholds. However, up to 4-week post-perforation, DPOAEs never fully recovered to the levels obtained with normal intact TM, consistent with the incomplete recovery of ABR thresholds and ME transmission, especially at high-frequency regions, which could be explained by an irregularly dense and thickened healed TM.

Since TM perforations in patients are commonly caused by either trauma or infection, the present results contribute towards providing insight into understanding ME transmission under pathological conditions as well as promoting the application of DPOAEs in the evaluation and diagnosis of deficits in the ME-transmission system.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2CDntAp

Feasibility of direct promontory stimulation by bone conduction: a preliminary study of frequency-response characteristics in cats

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Yu-Xuan Shi, Liu-Jie Ren, Lin Yang, Tian-Yu Zhang, You-Zhou Xie, Pei-Dong Dai

Abstract

Background

As an alternative pathway to air conduction, bone conduction is a multipathway process that transmits sound energy to the inner ear through the skull in general. Based on this mechanism, bone conduction devices (BCDs) have been used widely in the rehabilitation of hearing loss. Although great efforts have been devoted to improving BCDs, drawbacks still exist in most categories of BCDs due to the complicated process of bone conduction. We hypothesized that if a bone conduction transducer was placed on the cochlea to stimulate it directly, the attenuation would be minimized, and the frequency dependency would be different from that of the vibratory response induced by traditional BCDs. This study aimed to explore the feasibility of direct promontory stimulation and to investigate its frequency-response characteristics.

Methods

Measurements were conducted in twelve cat ears. To stimulate the promontory directly, the floating mass transducer (FMT) of the Vibrant Soundbridge^© (VSB) implant was glued to the promontory coupled with an oval window (OW) coupler. Auditory brainstem response (ABR) and laser Doppler vibrometry (LDV) measurements were used to evaluate the auditory response induced by the FMT. In both measurements, the FMT was driven by direct voltage stimuli.

Results

ABR waves could be induced under direct promontory stimulation by the FMT. In the frequency range of 1-12 kHz, the variation in the voltage threshold level were limited to 16 dB SPL with a maximum of 0.2 V at 1 kHz and a minimum of 0.04 V at 10 kHz. In the LDV measurements and the relative motion of the round window membrane (RWM) and the promontory were used to evaluate the cochlear response. The LDV results indicated a weak frequency dependency from 1-12 kHz.

Conclusion

Different from traditional stimulation via transcranial bone conduction, direct promontory stimulation is a new method in which a small bone conduction transducer stimulates the cochlear shell directly. The current experimental data demonstrate that it is feasible to generate sensations through bone conduction by stimulating the cochlea directly. Furthermore, the cochlear response induced by this type of stimulus in cats was weakly frequency dependent at frequencies ranging from 1-12 kHz. This study may provide a basis for the design of new transducers that can perform well over a wide range of frequencies.

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Effects of selective auditory-nerve damage on the behavioral audiogram and temporal integration in the budgerigar

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Stephanie J. Wong, Kristina S. Abrams, Kassidy N. Amburgey, Yingxuan Wang, Kenneth S. Henry

Abstract

Auditory-nerve fibers are lost steadily with age and as a possible consequence of noise-induced glutamate excitotoxicity. Auditory-nerve loss in the absence of other cochlear pathologies is thought to be undetectable with a pure-tone audiogram while degrading real-world speech perception (hidden hearing loss). Perceptual deficits remain unclear, however, due in part to the limited behavioral capacity of existing rodent models to discriminate complex sounds. The budgerigar is an avian vocal learner with human-like behavioral sensitivity to many simple and complex sounds and the capacity to mimic speech. Previous studies in this species show that intracochlear kainic-acid infusion reduces wave 1 of the auditory brainstem response by 40-70%, consistent with substantial excitotoxic auditory-nerve damage. The present study used operant-conditioning procedures in trained budgerigars to quantify kainic-acid effects on tone detection across frequency (0.25-8 kHz; the audiogram) and as a function of duration (20-160 ms; temporal integration). Tone thresholds in control animals were lowest from 1-4 kHz and decreased with increasing duration as in previous studies of the budgerigar. Behavioral results in kainic-acid-exposed animals were as sensitive as in controls, suggesting preservation of the audiogram and temporal integration despite auditory-nerve loss associated with up to 70% wave 1 reduction. Distortion-product otoacoustic emissions were also preserved in kainic-acid exposed animals, consistent with normal hair-cell function. These results highlight considerable perceptual resistance of tone-detection performance with selective auditory-nerve loss. Future behavioral studies in budgerigars with auditory-nerve damage can use complex speech-like stimuli to help clarify aspects of auditory perception impacted by this common cochlear pathology.

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Effects of selective auditory-nerve damage on the behavioral audiogram and temporal integration in the budgerigar

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Stephanie J. Wong, Kristina S. Abrams, Kassidy N. Amburgey, Yingxuan Wang, Kenneth S. Henry

Abstract

Auditory-nerve fibers are lost steadily with age and as a possible consequence of noise-induced glutamate excitotoxicity. Auditory-nerve loss in the absence of other cochlear pathologies is thought to be undetectable with a pure-tone audiogram while degrading real-world speech perception (hidden hearing loss). Perceptual deficits remain unclear, however, due in part to the limited behavioral capacity of existing rodent models to discriminate complex sounds. The budgerigar is an avian vocal learner with human-like behavioral sensitivity to many simple and complex sounds and the capacity to mimic speech. Previous studies in this species show that intracochlear kainic-acid infusion reduces wave 1 of the auditory brainstem response by 40-70%, consistent with substantial excitotoxic auditory-nerve damage. The present study used operant-conditioning procedures in trained budgerigars to quantify kainic-acid effects on tone detection across frequency (0.25-8 kHz; the audiogram) and as a function of duration (20-160 ms; temporal integration). Tone thresholds in control animals were lowest from 1-4 kHz and decreased with increasing duration as in previous studies of the budgerigar. Behavioral results in kainic-acid-exposed animals were as sensitive as in controls, suggesting preservation of the audiogram and temporal integration despite auditory-nerve loss associated with up to 70% wave 1 reduction. Distortion-product otoacoustic emissions were also preserved in kainic-acid exposed animals, consistent with normal hair-cell function. These results highlight considerable perceptual resistance of tone-detection performance with selective auditory-nerve loss. Future behavioral studies in budgerigars with auditory-nerve damage can use complex speech-like stimuli to help clarify aspects of auditory perception impacted by this common cochlear pathology.

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Reliability and interrelations of seven proxy measures of cochlear synaptopathy

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Hannah Guest, Kevin J. Munro, Garreth Prendergast, Christopher J. Plack

Abstract

Investigations of cochlear synaptopathy in living humans rely on proxy measures of auditory nerve function. Numerous procedures have been developed, typically based on the auditory brainstem response (ABR), envelope-following response (EFR), or middle-ear-muscle reflex (MEMR). Validation is challenging, due to the absence of a gold-standard measure in humans. Some metrics correlate with synaptic survival in animal models, but translation between species is not straightforward; measurements in humans are likely to reflect greater error and greater variability from non-synaptopathic sources. The present study assessed the reliability of seven measures, as well as testing for correlations between them. Thirty-one young women with normal audiograms underwent repeated measurements of ABR wave I amplitude, ABR wave I growth, ABR wave V latency shift in noise, EFR amplitude, EFR growth with stimulus modulation depth, MEMR threshold, and an MEMR across-frequency difference measure. Intraclass correlation coefficients for ABR wave I amplitude, EFR amplitude, and MEMR threshold ranged from 0.85 to 0.93, suggesting that such tests can yield highly reliable results, given careful measurement techniques. The ABR and EFR difference measures exhibited only poor-to-moderate reliability. No significant correlations, nor any consistent trends, were observed between the various measures, providing no indication that these metrics reflect the same underlying physiological processes. Findings suggest that many proxy measures of cochlear synaptopathy should be regarded with caution, at least when employed in young adults with normal audiograms.

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Complementary And Distinct Roles Of Autophagy, Apoptosis And Senescence During Early Inner Ear Development

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Isabel Varela-Nieto, Ignacio Palmero, Marta Magariños

Abstract

The development of the inner ear complex cytoarchitecture and functional geometry requires the exquisite coordination of a variety of cellular processes in a temporal manner. At early stages of inner ear development several rounds of cell proliferation in the otocyst promote the growth of the structure. The apoptotic program is initiated in exceeding cells to adjust cell type numbers. Apoptotic cells are cleared by phagocytic cells that recognize the phosphatidylserine residues exposed in the cell membrane thanks to the energy supplied by autophagy. Specific molecular programs determine hair and supporting cell fate, these populations are responsible for the functions of the adult sensory organ: detection of sound, position and acceleration. The neurons that transmit auditory and balance information to the brain are also born at the otocyst by neurogenesis facilitated by autophagy.

Cellular senescence participates in tissue repair, cancer and aging, situations in which cells enter a permanent cell cycle arrest and acquire a highly secretory phenotype that modulates their microenvironment. More recently, senescence has also been proposed to take place during vertebrate development in a limited number of transitory structures and organs; among the later, the endolymphatic duct in the inner ear.

Here, we review these cellular processes during the early development of the inner ear, focusing on how the most recently described cellular senescence participates and cooperates with proliferation, apoptosis and autophagy to achieve otic morphogenesis and differentiation.

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Complementary And Distinct Roles Of Autophagy, Apoptosis And Senescence During Early Inner Ear Development

Publication date: Available online 23 January 2019

Source: Hearing Research

Author(s): Isabel Varela-Nieto, Ignacio Palmero, Marta Magariños

Abstract

The development of the inner ear complex cytoarchitecture and functional geometry requires the exquisite coordination of a variety of cellular processes in a temporal manner. At early stages of inner ear development several rounds of cell proliferation in the otocyst promote the growth of the structure. The apoptotic program is initiated in exceeding cells to adjust cell type numbers. Apoptotic cells are cleared by phagocytic cells that recognize the phosphatidylserine residues exposed in the cell membrane thanks to the energy supplied by autophagy. Specific molecular programs determine hair and supporting cell fate, these populations are responsible for the functions of the adult sensory organ: detection of sound, position and acceleration. The neurons that transmit auditory and balance information to the brain are also born at the otocyst by neurogenesis facilitated by autophagy.

Cellular senescence participates in tissue repair, cancer and aging, situations in which cells enter a permanent cell cycle arrest and acquire a highly secretory phenotype that modulates their microenvironment. More recently, senescence has also been proposed to take place during vertebrate development in a limited number of transitory structures and organs; among the later, the endolymphatic duct in the inner ear.

Here, we review these cellular processes during the early development of the inner ear, focusing on how the most recently described cellular senescence participates and cooperates with proliferation, apoptosis and autophagy to achieve otic morphogenesis and differentiation.

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Comparison of the Effect of Topical Use of Nigella Sativa Oil and Diclofenac Gel on Osteoarthritis Pain in Older People: A Randomized, Double-blind, Clinical Trial

Publication date: Available online 23 January 2019

Source: Journal of Herbal Medicine

Author(s): Fatemeh Azizi, Fereshteh Ghorat, Mohammad Hassan Rakhshani, Mostafa Rad

Abstract

Osteoarthritis is one of the most common diseases in the elderly. Herbal remedies create pain relief with appropriate clinical effects and less toxicity. We aimed to investigate the effect of Nigella sativa oil compared with diclofenac gel on the reduction of osteoarthritis pain in older people. This was a double-blind clinical trial. Samples were 52 men and women aged 60-80 years. They were selected using a convenience method, that were randomly assigned into Nigella sativa oil and diclofenac gel groups. The topical application of Nigella sativa oil and diclofenac gel was performed twice a day in the morning and night for 21 days. The Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire was used for data collection about pain before the use of drugs, in the tenth day and the twenty-first day of the intervention. Paired t-test showed that both interventions improved pain in the subjects (P < 0.05). However, t-test and Mann-Whitney U test showed that pain on the 21 st day after the intervention was significantly lower in the Nigella sativa oil group compared with that of the diclofenac gel group (P = 0.04). Also, the results of this study showed that Nigella sativa oil had a better pain relief effect than diclofenac gel. The mean pain scores in the Nigella sativa oil and diclofenac gel groups before the intervention were 75 ± 16.29 and 57.66 ± 19.66, respectively. Also, pain on the 21 st day after the intervention was 38.88 ± 17.84 and 50.33 ± 20.38, respectively. In general, Nigella sativa oil was more effective than diclofenac gel on osteoarthritis pain.

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Management of jugular bulb injury during drilling of the internal auditory canal (ICA) for vestibular schwannoma surgery

Publication date: Available online 24 January 2019

Source: American Journal of Otolaryngology

Author(s): Sajjad Muhammad, Martin Lehecka, Saku T. Sinkkonen, Mika Niemelä

Abstract

The retrosigmoid approach for vestibular schwannoma surgery has remained the standard approach by most neurosurgeons. Drilling the posterior wall of the internal auditory meatus (IAM) is an essential step in removing the intrameatal tumor. During IAM drilling, three anatomical structures can be encountered, including the posterior semicircular canal, vestibular aqueduct, and jugular bulb. Any of these can be injured during drilling, especially if the jugular bulb lies above the inferior edge of the IAM. Although IAM drilling is performed in most vestibular schwannoma surgeries, information on how to manage complications such as jugular bulb injury is lacking. Here we use an intraoperative video to demonstrate how to manage the inadvertent injury to the jugular bulb in order to avoid massive blood loss. We present a case of a 39-year-old woman with hearing loss, diagnosed with a cerebellopontine angle mass extending into the IAM. Surgery was required due to tumor progression. We used the retrosigmoid approach to access the tumor. During IAM drilling, the jugular bulb was injured. A thin layer of bone wax was applied under continuous suction. The margins of the wax were then gently compressed with a dissector; great care was taken to avoid pushing the wax into the jugular bulb. Excess bone wax was removed (video 1). A small diamond drill (2 mm) was used for further drilling. Our instructional video shows the surgical approach, microsurgical anatomy, and technical aspects of managing massive bleeding from jugular bulb injury. It should therefore be helpful for young neurosurgeons.

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Management of jugular bulb injury during drilling of the internal auditory canal (ICA) for vestibular schwannoma surgery

Publication date: Available online 24 January 2019

Source: American Journal of Otolaryngology

Author(s): Sajjad Muhammad, Martin Lehecka, Saku T. Sinkkonen, Mika Niemelä

Abstract

The retrosigmoid approach for vestibular schwannoma surgery has remained the standard approach by most neurosurgeons. Drilling the posterior wall of the internal auditory meatus (IAM) is an essential step in removing the intrameatal tumor. During IAM drilling, three anatomical structures can be encountered, including the posterior semicircular canal, vestibular aqueduct, and jugular bulb. Any of these can be injured during drilling, especially if the jugular bulb lies above the inferior edge of the IAM. Although IAM drilling is performed in most vestibular schwannoma surgeries, information on how to manage complications such as jugular bulb injury is lacking. Here we use an intraoperative video to demonstrate how to manage the inadvertent injury to the jugular bulb in order to avoid massive blood loss. We present a case of a 39-year-old woman with hearing loss, diagnosed with a cerebellopontine angle mass extending into the IAM. Surgery was required due to tumor progression. We used the retrosigmoid approach to access the tumor. During IAM drilling, the jugular bulb was injured. A thin layer of bone wax was applied under continuous suction. The margins of the wax were then gently compressed with a dissector; great care was taken to avoid pushing the wax into the jugular bulb. Excess bone wax was removed (video 1). A small diamond drill (2 mm) was used for further drilling. Our instructional video shows the surgical approach, microsurgical anatomy, and technical aspects of managing massive bleeding from jugular bulb injury. It should therefore be helpful for young neurosurgeons.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2WhGdOK

Primary oral presentation of sarcoidosis in a pediatric patient

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery

Author(s): Chad Dammling, Peter Waite, Tim Beukelman

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Pharyngeal airway space changes after maxillomandibular advancement: a five-year retrospective study

Publication date: Available online 23 January 2019

Source: International Journal of Oral and Maxillofacial Surgery

Author(s): P.M. Araújo, R.L.V. Osterne, A.C.G. de Souza Carvalho, N.O. Azevedo, R.F. Gondim, R.T. Gonçalves Filho, E. Sant'Ana, R.L.M. Nogueira

Abstract

The aim of this study was to compare the alterations in three regions of the airway—nasopharynx, oropharynx, and hypopharynx—in relation to the area of the midsagittal plane, volume, and minimal axial area after maxillomandibular advancement (MMA) surgery. Thirty patients who had undergone MMA surgery were evaluated at four time points: preoperative (T0), immediately postoperative (T1), 1 year postoperative (T2), and ≥5 years postoperative (T3). All measurements were performed using computed tomography, analyzed in Dolphin Imaging 11.0 Premium 3D software. The area in the midsagittal plane presented a mean increase of 22.0% between T0 and T3 (P < 0.001), with the highest increase in the oropharynx (24.1%, P < 0.001). The total volumetric increase at T3 was 16.7% (P < 0.001), with the highest increase in the nasopharynx (15.7%; P < 0.001). The lowest minimal axial area was found for the oropharynx at all time points, and the highest increase in minimal axial area was found for the nasopharynx (114.9%; P < 0.001). MMA surgery showed the highest increase in upper posterior airway between T0 and T1, and this was followed by a progressive reduction until T3, but with a statistically significant increase at T3 compared with T0 in all cases.

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Skeletal stability in orthognathic surgery with the surgery first approach: a systematic review

Publication date: Available online 23 January 2019

Source: International Journal of Oral and Maxillofacial Surgery

Author(s): D. Soverina, G. Gasparini, S. Pelo, P. Doneddu, M. Todaro, R. Boniello, C. Azzuni, C. Grippaudo, G. Saponaro, G. D'Amato, U. Garagiola, A. Moro

Abstract

The surgery first approach (SFA) is a therapeutic strategy used in orthognathic surgery that is constantly evolving. With this approach, the pre-surgical orthodontic treatment can be eliminated, the maxilla and the mandible are surgically repositioned into the desired position, and the therapy is ended with a short orthodontic phase. Several studies have reported that the SFA is an acceptable approach, but postoperative stability is unclear. In this study, a systematic review on the SFA was performed. The PubMed, Google Scholar, Scopus, LexisNexis, Web of Science, and Cochrane Library databases were accessed. Studies from which data could be extracted on skeletal stability based on specific cephalometric points were included. The search yielded 2766 publications. Application of the selection criteria resulted in a final group of 14 articles. Five hundred and sixty patients with class III malocclusion underwent orthognathic surgery, 339 with the SFA. Study parameters such as evaluation time points and reference planes varied, making it impossible to perform a meta-analysis. The studies suggest that surgery with the SFA is as stable as surgery with the conventional approach. However, all articles described stability using a penultimate time point of 'after surgery' and not 'after debonding'; hence orthodontic movements and consequent mandibular movements could have influenced cephalometric measurements. Thus, to verify the real stability of the SFA, further research with longer follow-up periods is required, with evaluation at the same time points.

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Skeletal stability in orthognathic surgery with the surgery first approach: a systematic review

Publication date: Available online 23 January 2019

Source: International Journal of Oral and Maxillofacial Surgery

Author(s): D. Soverina, G. Gasparini, S. Pelo, P. Doneddu, M. Todaro, R. Boniello, C. Azzuni, C. Grippaudo, G. Saponaro, G. D'Amato, U. Garagiola, A. Moro

Abstract

The surgery first approach (SFA) is a therapeutic strategy used in orthognathic surgery that is constantly evolving. With this approach, the pre-surgical orthodontic treatment can be eliminated, the maxilla and the mandible are surgically repositioned into the desired position, and the therapy is ended with a short orthodontic phase. Several studies have reported that the SFA is an acceptable approach, but postoperative stability is unclear. In this study, a systematic review on the SFA was performed. The PubMed, Google Scholar, Scopus, LexisNexis, Web of Science, and Cochrane Library databases were accessed. Studies from which data could be extracted on skeletal stability based on specific cephalometric points were included. The search yielded 2766 publications. Application of the selection criteria resulted in a final group of 14 articles. Five hundred and sixty patients with class III malocclusion underwent orthognathic surgery, 339 with the SFA. Study parameters such as evaluation time points and reference planes varied, making it impossible to perform a meta-analysis. The studies suggest that surgery with the SFA is as stable as surgery with the conventional approach. However, all articles described stability using a penultimate time point of 'after surgery' and not 'after debonding'; hence orthodontic movements and consequent mandibular movements could have influenced cephalometric measurements. Thus, to verify the real stability of the SFA, further research with longer follow-up periods is required, with evaluation at the same time points.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2Mt6e9x

Pharyngeal airway space changes after maxillomandibular advancement: a five-year retrospective study

Publication date: Available online 23 January 2019

Source: International Journal of Oral and Maxillofacial Surgery

Author(s): P.M. Araújo, R.L.V. Osterne, A.C.G. de Souza Carvalho, N.O. Azevedo, R.F. Gondim, R.T. Gonçalves Filho, E. Sant'Ana, R.L.M. Nogueira

Abstract

The aim of this study was to compare the alterations in three regions of the airway—nasopharynx, oropharynx, and hypopharynx—in relation to the area of the midsagittal plane, volume, and minimal axial area after maxillomandibular advancement (MMA) surgery. Thirty patients who had undergone MMA surgery were evaluated at four time points: preoperative (T0), immediately postoperative (T1), 1 year postoperative (T2), and ≥5 years postoperative (T3). All measurements were performed using computed tomography, analyzed in Dolphin Imaging 11.0 Premium 3D software. The area in the midsagittal plane presented a mean increase of 22.0% between T0 and T3 (P < 0.001), with the highest increase in the oropharynx (24.1%, P < 0.001). The total volumetric increase at T3 was 16.7% (P < 0.001), with the highest increase in the nasopharynx (15.7%; P < 0.001). The lowest minimal axial area was found for the oropharynx at all time points, and the highest increase in minimal axial area was found for the nasopharynx (114.9%; P < 0.001). MMA surgery showed the highest increase in upper posterior airway between T0 and T1, and this was followed by a progressive reduction until T3, but with a statistically significant increase at T3 compared with T0 in all cases.

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Comparison of Nongated Chest CT and Dedicated Calcium Scoring CT for Coronary Calcium Quantification Using a 256-Dector Row CT Scanner

Publication date: Available online 23 January 2019

Source: Academic Radiology

Author(s): Yuhuan Chen, Zhijun Hu, Michelle Li, Yongjun Jia, Taiping He, Zhentang Liu, Donghong Wei, Yong Yu

Background

Coronary artery calcification (CAC) is a marker of atherosclerosis and an independent risk factor for cardiac-related mortality and frequently detected on noncontrast chest CT. We aimed to investigate the reliability and accuracy of determining CAC using noncontrast, nongated chest CT with 256-detector row.

Materials and Methods

A total of 1318 patients for chest examination were enrolled to undergo both nongated chest CT and dedicated calcium-scoring CT (CSCT) on a 256-detector row CT scanner. The chest CT was scanned in fast-helical mode with 8 cm collimation, 0.28 second rotation speed and pitch 0.992:1 to cover entire chest. CSCT used single prospective ECG-triggered cardiac axial mode with 0.28 second rotation speed covering only the heart. CAC scores (Agatston, mass, and volume) were determined using both image sets and were statistically compared.

Results

Sensitivity and specificity of nongated chest CT for determining positive CAC was 94.8% (182/192) and 100%, respectively. The agreement in assessing the quantitative Agatston, volume, and mass scores between the nongated chest CT and CSCT was almost perfect, with the intraclass correlation coefficient values of 0.998, 0.999, and 0.999, respectively. Additionally, there was a good agreement in CAC quantification between the nongated chest CT and dedicated CSCT with small coefficient of variation: mass score (9.0%), volume score (9.5%), and Agatston score (12.6%).

Conclusion

Nongated chest CT with 256-detector row is a reliable imaging mode for detecting and quantifying calcifications in coronary arteries compared with dedicated calcium-scoring CT.

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Comparison of Nongated Chest CT and Dedicated Calcium Scoring CT for Coronary Calcium Quantification Using a 256-Dector Row CT Scanner

Publication date: Available online 23 January 2019

Source: Academic Radiology

Author(s): Yuhuan Chen, Zhijun Hu, Michelle Li, Yongjun Jia, Taiping He, Zhentang Liu, Donghong Wei, Yong Yu

Background

Coronary artery calcification (CAC) is a marker of atherosclerosis and an independent risk factor for cardiac-related mortality and frequently detected on noncontrast chest CT. We aimed to investigate the reliability and accuracy of determining CAC using noncontrast, nongated chest CT with 256-detector row.

Materials and Methods

A total of 1318 patients for chest examination were enrolled to undergo both nongated chest CT and dedicated calcium-scoring CT (CSCT) on a 256-detector row CT scanner. The chest CT was scanned in fast-helical mode with 8 cm collimation, 0.28 second rotation speed and pitch 0.992:1 to cover entire chest. CSCT used single prospective ECG-triggered cardiac axial mode with 0.28 second rotation speed covering only the heart. CAC scores (Agatston, mass, and volume) were determined using both image sets and were statistically compared.

Results

Sensitivity and specificity of nongated chest CT for determining positive CAC was 94.8% (182/192) and 100%, respectively. The agreement in assessing the quantitative Agatston, volume, and mass scores between the nongated chest CT and CSCT was almost perfect, with the intraclass correlation coefficient values of 0.998, 0.999, and 0.999, respectively. Additionally, there was a good agreement in CAC quantification between the nongated chest CT and dedicated CSCT with small coefficient of variation: mass score (9.0%), volume score (9.5%), and Agatston score (12.6%).

Conclusion

Nongated chest CT with 256-detector row is a reliable imaging mode for detecting and quantifying calcifications in coronary arteries compared with dedicated calcium-scoring CT.

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Primary oral presentation of sarcoidosis in a pediatric patient

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery

Author(s): Chad Dammling, Peter Waite, Tim Beukelman

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What are the parameters for reoperation in mandibular third molars submitted to coronectomy? A systematic review

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery

Author(s): Bhárbara Marinho Barcellos, Bibiana Dalsasso Velasques, Lucas Borin Moura, Cristina Braga Xavier

Purpose

Coronectomy is an alternative technique to conventional lower third molar removal which aims to reduce inferior alveolar nerve impairment. The study's purpose is to identify factors associated with reoperation after mandibular third molar coronectomy.

Material and Methods

This systematic review sought for scientific articles in PubMed/MEDLINE, Elsevier/Scopus, and Cochrane Library databases. Studies that evaluated reoperation from coronectomy and a minimum follow-up of six months were included. The PRISMA quality assessment of the included articles was performed, and the following data were analyzed: demographic characteristics, reason for reoperation and time between coronectomy and reoperation. The data was submitted to descriptive analysis.

Results

The initial search found 362 studies and 15 were included in the final review. In total, 1664 patients and 2062 teeth were submitted to coronectomy. Most of them were female (60.58%). The follow-up period for reoperation ranged from 6 months to 10 years and mean until the second procedure time was 10.4 months (Q₁=3; Q₃=8.5). Only 105 (5.1%) teeth were reoperated. The main reasons for reoperation were root exposure (53.33%), infection (10.47%), pain (9.52%) and enamel residual (9.52%). Regarding to PRISMA quality evaluation, only one article presented low risk of bias.

Conclusion

Reoperation after mandibular third molar coronectomy is low, around 5% of the cases; the main reasons were residual root exposure and symptomatology. Due the possibility of late exposure or symptomatology, we recommend a follow-up longer than six months until the root exposure or the end of migration process.

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What are the parameters for reoperation in mandibular third molars submitted to coronectomy? A systematic review

Publication date: Available online 23 January 2019

Source: Journal of Oral and Maxillofacial Surgery

Author(s): Bhárbara Marinho Barcellos, Bibiana Dalsasso Velasques, Lucas Borin Moura, Cristina Braga Xavier

Purpose

Coronectomy is an alternative technique to conventional lower third molar removal which aims to reduce inferior alveolar nerve impairment. The study's purpose is to identify factors associated with reoperation after mandibular third molar coronectomy.

Material and Methods

This systematic review sought for scientific articles in PubMed/MEDLINE, Elsevier/Scopus, and Cochrane Library databases. Studies that evaluated reoperation from coronectomy and a minimum follow-up of six months were included. The PRISMA quality assessment of the included articles was performed, and the following data were analyzed: demographic characteristics, reason for reoperation and time between coronectomy and reoperation. The data was submitted to descriptive analysis.

Results

The initial search found 362 studies and 15 were included in the final review. In total, 1664 patients and 2062 teeth were submitted to coronectomy. Most of them were female (60.58%). The follow-up period for reoperation ranged from 6 months to 10 years and mean until the second procedure time was 10.4 months (Q₁=3; Q₃=8.5). Only 105 (5.1%) teeth were reoperated. The main reasons for reoperation were root exposure (53.33%), infection (10.47%), pain (9.52%) and enamel residual (9.52%). Regarding to PRISMA quality evaluation, only one article presented low risk of bias.

Conclusion

Reoperation after mandibular third molar coronectomy is low, around 5% of the cases; the main reasons were residual root exposure and symptomatology. Due the possibility of late exposure or symptomatology, we recommend a follow-up longer than six months until the root exposure or the end of migration process.

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The Evaluation of Tryptase after Subcutaneous Immunotherapy-Associated Systemic Reactions

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Sofia szari, Priscilla H. Wong, Howard C. Crisp, Edward Champoux, Tonya S. Rans, Christopher A. Coop

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Disparities persist in asthma-related emergency department visits among Chicago children

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Anna Volerman, Kristin Kan, Erica Salem, Nik Prachand, Chris M. Warren, Dominique Sighoko, Ruchi S. Gupta

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New IgE Immediate Hypersensitivity Reactions Upon Reintroduction of Food Restricted for Treatment of Eosinophilic Esophagitis

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Steven J. Gottlieb, Jonathan E. Markowitz, Evan S. Dellon

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New IgE Immediate Hypersensitivity Reactions Upon Reintroduction of Food Restricted for Treatment of Eosinophilic Esophagitis

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Steven J. Gottlieb, Jonathan E. Markowitz, Evan S. Dellon

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The Evaluation of Tryptase after Subcutaneous Immunotherapy-Associated Systemic Reactions

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Sofia szari, Priscilla H. Wong, Howard C. Crisp, Edward Champoux, Tonya S. Rans, Christopher A. Coop

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Disparities persist in asthma-related emergency department visits among Chicago children

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Anna Volerman, Kristin Kan, Erica Salem, Nik Prachand, Chris M. Warren, Dominique Sighoko, Ruchi S. Gupta

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A Peripheral Cause of Asthma: Peripheral T-cell Lymphoma

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Richard P. Ramonell, Merin Kuruvilla, Gabriel Sica, Remzi Bag, F. Eun-Hyung Lee

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A Peripheral Cause of Asthma: Peripheral T-cell Lymphoma

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Richard P. Ramonell, Merin Kuruvilla, Gabriel Sica, Remzi Bag, F. Eun-Hyung Lee

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Ethanol LOCK & Immunoglobulin LOAD: Improving the Clinical Course of Tricho-hepato-enteric Syndrome

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Catherine A. Popadiuk, Diana R. Lindsey, Milissa U. Jones, Cecilia P. Mikita

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Ethanol LOCK & Immunoglobulin LOAD: Improving the Clinical Course of Tricho-hepato-enteric Syndrome

Publication date: Available online 24 January 2019

Source: Annals of Allergy, Asthma & Immunology

Author(s): Catherine A. Popadiuk, Diana R. Lindsey, Milissa U. Jones, Cecilia P. Mikita

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Open anterior skull base surgery in the pediatric population: anatomy, approaches, and considerations

Publication date: Available online 24 January 2019

Source: Operative Techniques in Otolaryngology-Head and Neck Surgery

Author(s): Tristan Tham, Peter Costantino

The objectives of this paper are to synthesize the existing literature on open approaches to the anterior skull base in children. First, we review the developmental anatomy of the anterior skull base. Next, we describe the most commonly used open approaches to the anterior skull base and other adjunctive procedures. Lastly, we review the reconstructive options and comment important pediatric-specific considerations. Our review reports the variety of open approaches to access the anterior skull base in children. Detailed preoperative planning, taking age-related considerations into account, is necessary in order to plan to type and extent of access and reconstruction.

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Microvascular reconstruction and dental rehabilitation of benign severely atrophic jaws and defects of the alveolar ridge: our philosophy in 2019

Publication date: Available online 23 January 2019

Source: British Journal of Oral and Maxillofacial Surgery

Author(s): G.B. Bottini, A. Gaggl, C. Brandtner, J. Wittig, C. Steiner, C. List, F. Hartig

Abstract

We deal regularly with patients who present with severe atrophy of the jaws, compromised soft tissue, or penetrating defects of the alveolar ridge that are not the result of malignant disease. For these patients we use microvascular bony flaps together with dental implants and implant-supported prostheses. The purpose of this retrospective study was to present our current management and the lessons we have learned over a 16-year period while treating 86 patients for these indications with 87 microvascular bone flaps. We used a transoral approach for the anastomosis in 60 flaps, thereby avoiding visible scars, and inserted 281 dental implants to support fixed or removable dental prostheses. Two femoral flaps developed partial necrosis, and seven implants were lost. Eighty-five of the 86 patients were satisfied with the improvement in their orofacial function and aesthetics. Poor oral hygiene, active osteomyelitis, and severe bruxism are absolute contraindications.

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Open anterior skull base surgery in the pediatric population: anatomy, approaches, and considerations

Publication date: Available online 24 January 2019

Source: Operative Techniques in Otolaryngology-Head and Neck Surgery

Author(s): Tristan Tham, Peter Costantino

The objectives of this paper are to synthesize the existing literature on open approaches to the anterior skull base in children. First, we review the developmental anatomy of the anterior skull base. Next, we describe the most commonly used open approaches to the anterior skull base and other adjunctive procedures. Lastly, we review the reconstructive options and comment important pediatric-specific considerations. Our review reports the variety of open approaches to access the anterior skull base in children. Detailed preoperative planning, taking age-related considerations into account, is necessary in order to plan to type and extent of access and reconstruction.

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Microvascular reconstruction and dental rehabilitation of benign severely atrophic jaws and defects of the alveolar ridge: our philosophy in 2019

Publication date: Available online 23 January 2019

Source: British Journal of Oral and Maxillofacial Surgery

Author(s): G.B. Bottini, A. Gaggl, C. Brandtner, J. Wittig, C. Steiner, C. List, F. Hartig

Abstract

We deal regularly with patients who present with severe atrophy of the jaws, compromised soft tissue, or penetrating defects of the alveolar ridge that are not the result of malignant disease. For these patients we use microvascular bony flaps together with dental implants and implant-supported prostheses. The purpose of this retrospective study was to present our current management and the lessons we have learned over a 16-year period while treating 86 patients for these indications with 87 microvascular bone flaps. We used a transoral approach for the anastomosis in 60 flaps, thereby avoiding visible scars, and inserted 281 dental implants to support fixed or removable dental prostheses. Two femoral flaps developed partial necrosis, and seven implants were lost. Eighty-five of the 86 patients were satisfied with the improvement in their orofacial function and aesthetics. Poor oral hygiene, active osteomyelitis, and severe bruxism are absolute contraindications.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2HuPb8c

Clinical associations of T2-weighted lesion load and lesion location in small vessel disease: Insights from a large prospective cohort study

Publication date: Available online 24 January 2019

Source: NeuroImage

Author(s): Anna Altermatt, Laura Gaetano, Stefano Magon, Lorena Bauer, Regina Feurer, Hans Gnahn, Julia Hartmann, Christian L. Seifert, Holger Poppert, Jens Wuerfel, Ernst-Wilhelm Radue, Ludwig Kappos, Till Sprenger

Abstract

Background

Subcortical T2-weighted (T2w) lesions are very common in older adults and have been associated with dementia. However, little is known about the strategic lesion distribution and how lesion patterns relate to vascular risk factors and cognitive impairment.

Aim

The aim of this study was to analyze the association between T2w lesion load and location, vascular risk factors, and cognitive impairment in a large cohort of older adults.

Methods

1017 patients participating in a large prospective cohort study (INtervention project on cerebroVAscular disease and Dementia in the district of Ebersberg, INVADE II) were analyzed. Cerebral T2w white matter and deep grey matter lesions, the so-called white matter hyperintensities (WMHs), were outlined semi-automatically on fluid attenuated inversion recovery images and normalized to standard stereotaxic space (MNI152) by non-linear registration. Patients were assigned to either a high-risk or a low-risk group. The risk assessment considered ankle brachial index, intima media thickness, carotid artery stenosis, atrial fibrillation, previous cerebro-/cardiovascular events and peripheral artery disease as well as a score based on cholesterol levels, blood pressure and smoking. Separate lesion distributions were obtained for the two risk groups and compared using voxel-based lesion-symptom mapping. Moreover, we assessed the relation between lesion location and cognitive impairment (demographically adjusted z-scores of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery Plus, CERAD-NAB Plus) using voxel-based statistics (α = 0.05).

Results

A total of 878 out of 1017 subjects (86%) had evaluable MRI data and were included in the analyses (mean age: 68.2 ± 7.6 years, female: 515). Patients in the high-risk group were characterized by a significantly higher age, a higher proportion of men, a higher lesion load (p < 0.001), and a worse performance in some of the cognitive subdomain scores (p < 0.05). Voxels with significant associations to the subjects' cerebrovascular risk profiles were mainly found at locations of the corpus callosum, superior corona radiata, superior longitudinal fasciculus, internal and external capsule, and putamen. While several cognitive domains have shown significant associations with the participants' total lesion burden (p < 0.05), no focal WMH locations were found to be associated with cognitive impairment.

Conclusion

Age, gender, several cognitive scores, and WMH lesion load were shown to be significantly associated with vascular risk factors in a population of older, but cognitively preserved adults. Vascular risk factors seem to promote lesion formation most severely at well-defined locations. While lesion load showed weak associations to some cognitive scores, no focal locations causing specific cognitive disturbances were identified in this large cohort of older adults.

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Magnetoencephalography and the infant brain

Publication date: Available online 24 January 2019

Source: NeuroImage

Author(s): Yu-Han Chen, Joni Saby, Emily Kuschner, William Gaetz, J. Christopher Edgar, Timothy P.L. Roberts

Abstract

Magnetoencephalography (MEG) is a non-invasive neuroimaging technique that provides whole-head measures of neural activity with millisecond temporal resolution. Over the last three decades, MEG has been used for assessing brain activity, most commonly in adults. MEG has been used less often to examine neural function during early development, in large part due to the fact that infant whole-head MEG systems have only recently been developed. In this review, an overview of infant MEG studies is provided, focusing on the period from birth to three years. The advantages of MEG for measuring neural activity in infants are highlighted, including the ability to assess activity in brain (source) space rather than sensor space, thus allowing direct assessment of neural generator activity. Recent advances in MEG hardware and source analysis are also discussed. As the review indicates, efforts in this area demonstrate that MEG is a promising technology for studying the infant brain. As a noninvasive technology, with emerging hardware providing the necessary sensitivity, an expected deliverable is the capability for longitudinal infant MEG studies evaluating the developmental trajectory (maturation) of neural activity. It is expected that departures from neuro-typical trajectories will offer early detection and prognosis insights in infants and toddlers at-risk for neurodevelopmental disorders, thus paving the way for early targeted interventions.

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Generalized diffusion spectrum magnetic resonance imaging (GDSI) for model-free reconstruction of the ensemble average propagator

Publication date: Available online 23 January 2019

Source: NeuroImage

Author(s): Qiyuan Tian, Grant Yang, Christoph W.U. Leuze, Ariel Rokem, Brian L. Edlow, Jennifer A. McNab

Abstract

Diffusion spectrum MRI (DSI) provides model-free estimation of the diffusion ensemble average propagator (EAP) and orientation distribution function (ODF) but requires the diffusion data to be acquired on a Cartesian q-space grid. Multi-shell diffusion acquisitions are more flexible and more commonly acquired but have, thus far, only been compatible with model-based analysis methods. Here, we propose a generalized DSI (GDSI) framework to recover the EAP from multi-shell diffusion MRI data. The proposed GDSI approach corrects for q-space sampling density non-uniformity using a fast geometrical approach. The EAP is directly calculated in a preferable coordinate system by multiplying the sampling density corrected q-space signals by a discrete Fourier transform matrix, without any need for gridding. The EAP is demonstrated as a way to map diffusion patterns in brain regions such as the thalamus, cortex and brainstem where the tissue microstructure is not as well characterized as in white matter. Scalar metrics such as the zero displacement probability and displacement distances at different fractions of the zero displacement probability were computed from the recovered EAP to characterize the diffusion pattern within each voxel. The probability averaged across directions at a specific displacement distance provides a diffusion property based image contrast that clearly differentiates tissue types. The displacement distance at the first zero crossing of the EAP averaged across directions orthogonal to the primary fiber orientation in the corpus callosum is found to be larger in the body (5.65 ± 0.09 μm) than in the genu (5.55 ± 0.15 μm) and splenium (5.4 ± 0.15 μm) of the corpus callosum, which corresponds well to prior histological studies. The EAP also provides model-free representations of angular structure such as the diffusion ODF, which allows estimation and comparison of fiber orientations from both the model-free and model-based methods on the same multi-shell data. For the model-free methods, detection of crossing fibers is found to be strongly dependent on the maximum b-value and less sensitive compared to the model-based methods. In conclusion, our study provides a generalized DSI approach that allows flexible reconstruction of the diffusion EAP and ODF from multi-shell diffusion data and data acquired with other sampling patterns.

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Clinical associations of T2-weighted lesion load and lesion location in small vessel disease: Insights from a large prospective cohort study

Publication date: Available online 24 January 2019

Source: NeuroImage

Author(s): Anna Altermatt, Laura Gaetano, Stefano Magon, Lorena Bauer, Regina Feurer, Hans Gnahn, Julia Hartmann, Christian L. Seifert, Holger Poppert, Jens Wuerfel, Ernst-Wilhelm Radue, Ludwig Kappos, Till Sprenger

Abstract

Background

Subcortical T2-weighted (T2w) lesions are very common in older adults and have been associated with dementia. However, little is known about the strategic lesion distribution and how lesion patterns relate to vascular risk factors and cognitive impairment.

Aim

The aim of this study was to analyze the association between T2w lesion load and location, vascular risk factors, and cognitive impairment in a large cohort of older adults.

Methods

1017 patients participating in a large prospective cohort study (INtervention project on cerebroVAscular disease and Dementia in the district of Ebersberg, INVADE II) were analyzed. Cerebral T2w white matter and deep grey matter lesions, the so-called white matter hyperintensities (WMHs), were outlined semi-automatically on fluid attenuated inversion recovery images and normalized to standard stereotaxic space (MNI152) by non-linear registration. Patients were assigned to either a high-risk or a low-risk group. The risk assessment considered ankle brachial index, intima media thickness, carotid artery stenosis, atrial fibrillation, previous cerebro-/cardiovascular events and peripheral artery disease as well as a score based on cholesterol levels, blood pressure and smoking. Separate lesion distributions were obtained for the two risk groups and compared using voxel-based lesion-symptom mapping. Moreover, we assessed the relation between lesion location and cognitive impairment (demographically adjusted z-scores of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery Plus, CERAD-NAB Plus) using voxel-based statistics (α = 0.05).

Results

A total of 878 out of 1017 subjects (86%) had evaluable MRI data and were included in the analyses (mean age: 68.2 ± 7.6 years, female: 515). Patients in the high-risk group were characterized by a significantly higher age, a higher proportion of men, a higher lesion load (p < 0.001), and a worse performance in some of the cognitive subdomain scores (p < 0.05). Voxels with significant associations to the subjects' cerebrovascular risk profiles were mainly found at locations of the corpus callosum, superior corona radiata, superior longitudinal fasciculus, internal and external capsule, and putamen. While several cognitive domains have shown significant associations with the participants' total lesion burden (p < 0.05), no focal WMH locations were found to be associated with cognitive impairment.

Conclusion

Age, gender, several cognitive scores, and WMH lesion load were shown to be significantly associated with vascular risk factors in a population of older, but cognitively preserved adults. Vascular risk factors seem to promote lesion formation most severely at well-defined locations. While lesion load showed weak associations to some cognitive scores, no focal locations causing specific cognitive disturbances were identified in this large cohort of older adults.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2FKsY4q

Magnetoencephalography and the infant brain

Publication date: Available online 24 January 2019

Source: NeuroImage

Author(s): Yu-Han Chen, Joni Saby, Emily Kuschner, William Gaetz, J. Christopher Edgar, Timothy P.L. Roberts

Abstract

Magnetoencephalography (MEG) is a non-invasive neuroimaging technique that provides whole-head measures of neural activity with millisecond temporal resolution. Over the last three decades, MEG has been used for assessing brain activity, most commonly in adults. MEG has been used less often to examine neural function during early development, in large part due to the fact that infant whole-head MEG systems have only recently been developed. In this review, an overview of infant MEG studies is provided, focusing on the period from birth to three years. The advantages of MEG for measuring neural activity in infants are highlighted, including the ability to assess activity in brain (source) space rather than sensor space, thus allowing direct assessment of neural generator activity. Recent advances in MEG hardware and source analysis are also discussed. As the review indicates, efforts in this area demonstrate that MEG is a promising technology for studying the infant brain. As a noninvasive technology, with emerging hardware providing the necessary sensitivity, an expected deliverable is the capability for longitudinal infant MEG studies evaluating the developmental trajectory (maturation) of neural activity. It is expected that departures from neuro-typical trajectories will offer early detection and prognosis insights in infants and toddlers at-risk for neurodevelopmental disorders, thus paving the way for early targeted interventions.

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Generalized diffusion spectrum magnetic resonance imaging (GDSI) for model-free reconstruction of the ensemble average propagator

Publication date: Available online 23 January 2019

Source: NeuroImage

Author(s): Qiyuan Tian, Grant Yang, Christoph W.U. Leuze, Ariel Rokem, Brian L. Edlow, Jennifer A. McNab

Abstract

Diffusion spectrum MRI (DSI) provides model-free estimation of the diffusion ensemble average propagator (EAP) and orientation distribution function (ODF) but requires the diffusion data to be acquired on a Cartesian q-space grid. Multi-shell diffusion acquisitions are more flexible and more commonly acquired but have, thus far, only been compatible with model-based analysis methods. Here, we propose a generalized DSI (GDSI) framework to recover the EAP from multi-shell diffusion MRI data. The proposed GDSI approach corrects for q-space sampling density non-uniformity using a fast geometrical approach. The EAP is directly calculated in a preferable coordinate system by multiplying the sampling density corrected q-space signals by a discrete Fourier transform matrix, without any need for gridding. The EAP is demonstrated as a way to map diffusion patterns in brain regions such as the thalamus, cortex and brainstem where the tissue microstructure is not as well characterized as in white matter. Scalar metrics such as the zero displacement probability and displacement distances at different fractions of the zero displacement probability were computed from the recovered EAP to characterize the diffusion pattern within each voxel. The probability averaged across directions at a specific displacement distance provides a diffusion property based image contrast that clearly differentiates tissue types. The displacement distance at the first zero crossing of the EAP averaged across directions orthogonal to the primary fiber orientation in the corpus callosum is found to be larger in the body (5.65 ± 0.09 μm) than in the genu (5.55 ± 0.15 μm) and splenium (5.4 ± 0.15 μm) of the corpus callosum, which corresponds well to prior histological studies. The EAP also provides model-free representations of angular structure such as the diffusion ODF, which allows estimation and comparison of fiber orientations from both the model-free and model-based methods on the same multi-shell data. For the model-free methods, detection of crossing fibers is found to be strongly dependent on the maximum b-value and less sensitive compared to the model-based methods. In conclusion, our study provides a generalized DSI approach that allows flexible reconstruction of the diffusion EAP and ODF from multi-shell diffusion data and data acquired with other sampling patterns.

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Number of positive nodes – Current relevance in determining prognosis of oral cavity cancer after the recent AJCC staging update

Publication date: March 2019

Source: Oral Oncology, Volume 90

Author(s): Suhas Kodasoge Rajappa, Udip Maheshwari, Jiten Jaipuria, Anupam Kumar Singh, Sumit Goyal, Ullas Batra, Rajeev Kumar, Ajay Kumar Dewan

Abstract

Introduction

Lymph node involvement and the number of positive nodes is a significant prognosticator in oral cavity cancers and current staging system does not incorporate it as an integral part.

Material and methods

This was a retrospective study of oral cavity cancer patients who were operated during the time period of 2009–2017. The data was collected and analysed to assess the impact of increase in the number of positive nodes on survival and its comparison of survival statistics to current AJCC staging.

Results

A total of 1431 patients were included in this study and 32.5% of these patients had a node positive disease. Nodal positivity was a significant prognosticator on multivariate analysis. Number of positive nodes was modelled with restricted cubic spline function and it showed progressive worsening of survival functions with increase in number. On Kaplan Meier analysis there was a better separation of curves when number of positive nodes was used and Akaike information criterion (AIC) showed that it was a better prognosticator than existing AJCC staging.

Conclusion

Number of positive nodes is a significant prognosticator of prognosis and hence should be considered in the AJCC staging system.

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Number of positive nodes – Current relevance in determining prognosis of oral cavity cancer after the recent AJCC staging update

Publication date: March 2019

Source: Oral Oncology, Volume 90

Author(s): Suhas Kodasoge Rajappa, Udip Maheshwari, Jiten Jaipuria, Anupam Kumar Singh, Sumit Goyal, Ullas Batra, Rajeev Kumar, Ajay Kumar Dewan

Abstract

Introduction

Lymph node involvement and the number of positive nodes is a significant prognosticator in oral cavity cancers and current staging system does not incorporate it as an integral part.

Material and methods

This was a retrospective study of oral cavity cancer patients who were operated during the time period of 2009–2017. The data was collected and analysed to assess the impact of increase in the number of positive nodes on survival and its comparison of survival statistics to current AJCC staging.

Results

A total of 1431 patients were included in this study and 32.5% of these patients had a node positive disease. Nodal positivity was a significant prognosticator on multivariate analysis. Number of positive nodes was modelled with restricted cubic spline function and it showed progressive worsening of survival functions with increase in number. On Kaplan Meier analysis there was a better separation of curves when number of positive nodes was used and Akaike information criterion (AIC) showed that it was a better prognosticator than existing AJCC staging.

Conclusion

Number of positive nodes is a significant prognosticator of prognosis and hence should be considered in the AJCC staging system.

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Exploring the Use of ECochG Testing During Electrode Insertion in Cochlear Implant Surgery

Conditions:   Cochlear Implants;   Hearing Preservation Intervention:   Procedure: Electrocochlography Sponsors:   Cambridge University Hospitals NHS Foundation Trust;   University of Cambridge Recruiting (Source: ClinicalTrials.gov)

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Exploring the Use of ECochG Testing During Electrode Insertion in Cochlear Implant Surgery

Conditions:   Cochlear Implants;   Hearing Preservation Intervention:   Procedure: Electrocochlography Sponsors:   Cambridge University Hospitals NHS Foundation Trust;   University of Cambridge Recruiting (Source: ClinicalTrials.gov)

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2CKh1I6

Microvascular reconstruction and dental rehabilitation of benign severely atrophic jaws and defects of the alveolar ridge: our philosophy in 2019

We deal regularly with patients who present with severe atrophy of the jaws, compromised soft tissue, or penetrating defects of the alveolar ridge that are not the result of malignant disease. For these patients we use microvascular bony flaps together with dental implants and implant-supported prostheses. The purpose of this retrospective study was to present our current management and the lessons we have learned over a 16-year period while treating 86 patients for these indications with 87 microvascular bone flaps. (Source: The British Journal of Oral and Maxillofacial Surgery)

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader http://bit.ly/2RZC3Mr

Microvascular reconstruction and dental rehabilitation of benign severely atrophic jaws and defects of the alveolar ridge: our philosophy in 2019

We deal regularly with patients who present with severe atrophy of the jaws, compromised soft tissue, or penetrating defects of the alveolar ridge that are not the result of malignant disease. For these patients we use microvascular bony flaps together with dental implants and implant-supported prostheses. The purpose of this retrospective study was to present our current management and the lessons we have learned over a 16-year period while treating 86 patients for these indications with 87 microvascular bone flaps. (Source: The British Journal of Oral and Maxillofacial Surgery)

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China Red Eye Study on Allergic Conjunctivitis

Condition:   Allergic Conjunctivitis Intervention:   Sponsor:   Sun Yat-sen University Active, not recruiting (Source: ClinicalTrials.gov)

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