Somatosensory responses to nothing: An MEG study of expectations during omission of tactile stimulations

Publication date: Available online 10 September 2018

Source: NeuroImage

Author(s): Lau M. Andersen, Daniel Lundqvist

Abstract

The brain builds up expectations to future events based on the patterns of past events. This function has been studied extensively in the auditory and visual domains using various oddball paradigms, but only little exploration of this phenomenon has been done in the somatosensory domain. In this study, we explore how expectations of somatosensory stimulations are established and expressed in neural activity as measured with magnetoencephalography. Using tactile stimulations to the index finger, we compared conditions with actual stimulation to conditions with omitted stimulations, both of which were either expected or unexpected.

Our results show that when a stimulation is expected but omitted, a time-locked response occurs ∼135 ms subsequent to the expected stimulation. This somatosensory response to "nothing" was source localized to the secondary somatosensory cortex and to the insula. This provides novel evidence of the capability of the brain of millisecond time-keeping of somatosensory patterns across intervals of 3000 ms.

Our results also show that when stimuli are repeated and expectations are established, there is associated activity in the theta and beta bands. These theta and beta band expressions of expectation were localized to the primary somatosensory area, inferior parietal cortex and cerebellum. Furthermore, there was gamma band activity in the right insula for the first stimulation after an omission, which indicates the detection of a new stimulation event after an expected pattern has been broken.

Finally, our results show that cerebellum play a crucial role in predicting upcoming stimulation and in predicting when stimulation may begin again.

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Load modulates the alpha and beta oscillatory dynamics serving verbal working memory

Publication date: Available online 10 September 2018

Source: NeuroImage

Author(s): Amy L. Proskovec, Elizabeth Heinrichs-Graham, Tony W. Wilson

Abstract

A network of predominantly left-lateralized brain regions has been linked to verbal working memory (VWM) performance. However, the impact of memory load on the oscillatory dynamics serving VWM is far less understood. To further investigate this, we had 26 healthy adults perform a high-load (6 letter) and low-load (4 letter) variant of a VWM task while undergoing magnetoencephalography (MEG). MEG data were evaluated in the time-frequency domain and significant oscillatory responses spanning the encoding and maintenance phases were reconstructed using a beamformer. To determine the impact of load on the neural dynamics, the resulting images were examined using paired-samples t-tests and virtual sensor analyses. Our results indicated stronger increases in frontal theta activity in the high-relative to low-load condition during early encoding. Stronger decreases in alpha/beta activity were also observed during encoding in bilateral posterior cortices during the high-load condition, and the strength of these load effects increased as encoding progressed. During maintenance, stronger decreases in alpha activity in the left inferior frontal gyrus, middle temporal gyrus, supramarginal gyrus, and inferior parietal cortices were detected during high-relative to low-load performance, with the strength of these load effects remaining largely static throughout maintenance. Finally, stronger increases in occipital alpha activity were observed during maintenance in the high-load condition, and the strength of these effects grew stronger with time during the first half of maintenance, before dissipating during the latter half of maintenance. Notably, this was the first study to utilize a whole-brain approach to statistically evaluate the temporal dynamics of load-related oscillatory differences during encoding and maintenance processes, and our results highlight the importance of spatial, temporal, and spectral specificity in this regard.

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Neural correlates of the energetic value of food during visual processing and response inhibition

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): P. Mengotti, F. Foroni, R.I. Rumiati

Abstract

Previous research showed that human brain regions involved in reward and cognitive control are responsive to visually presented food stimuli, in particular high-energy foods. However, it is still to be determined whether the preference towards high-energy foods depends on their higher energy density (kcal/gram), or is based on the difference in energy content of the food items (total amount of kcal). Here we report the results of an fMRI study in which normal-weight healthy participants processed food images during a one-back task or were required to inhibit their response towards food stimuli during a Go/No-Go task. High-energy density (HD) and low-energy density (LD) foods were matched for energy content displayed. Food-related kitchen objects (OBJ) were used as control stimuli. The lateral occipital complex and the orbitofrontal cortex showed consistent higher activity in response to HD than LD foods, both during visual processing and response inhibition. This result suggests that images of HD foods, even when the amount of food shown is not associated with a higher energy content, elicit preferential visual processing - possibly involving attentional processes - and trigger a response from the reward system. We conclude that the human brain is able to distinguish food energy densities of food items during both active visual processing and response inhibition.

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Neural correlates of the energetic value of food during visual processing and response inhibition

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): P. Mengotti, F. Foroni, R.I. Rumiati

Abstract

Previous research showed that human brain regions involved in reward and cognitive control are responsive to visually presented food stimuli, in particular high-energy foods. However, it is still to be determined whether the preference towards high-energy foods depends on their higher energy density (kcal/gram), or is based on the difference in energy content of the food items (total amount of kcal). Here we report the results of an fMRI study in which normal-weight healthy participants processed food images during a one-back task or were required to inhibit their response towards food stimuli during a Go/No-Go task. High-energy density (HD) and low-energy density (LD) foods were matched for energy content displayed. Food-related kitchen objects (OBJ) were used as control stimuli. The lateral occipital complex and the orbitofrontal cortex showed consistent higher activity in response to HD than LD foods, both during visual processing and response inhibition. This result suggests that images of HD foods, even when the amount of food shown is not associated with a higher energy content, elicit preferential visual processing - possibly involving attentional processes - and trigger a response from the reward system. We conclude that the human brain is able to distinguish food energy densities of food items during both active visual processing and response inhibition.

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Retrospective harmonization of multi-site diffusion MRI data acquired with different acquisition parameters

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): Suheyla Cetin Karayumak, Sylvain Bouix, Lipeng Ning, Anthony James, Tim Crow, Martha Shenton, Marek Kubicki, Yogesh Rathi

Abstract

A joint and integrated analysis of multi-site diffusion MRI (dMRI) datasets can dramatically increase the statistical power of neuroimaging studies and enable comparative studies pertaining to several brain disorders. However, dMRI data sets acquired on multiple scanners cannot be naively pooled for joint analysis due to scanner specific nonlinear effects as well as differences in acquisition parameters. Consequently, for joint analysis, the dMRI data has to be harmonized, which involves removing scanner-specific differences from the raw dMRI signal. In this work, we propose a dMRI harmonization method that is capable of removing scanner-specific effects, while accounting for minor differences in acquisition parameters such as b-value, spatial resolution and number of gradient directions. We validate our algorithm on dMRI data acquired from two sites: Philadelphia Neurodevelopmental Cohort (PNC) with 800 healthy adolescents (ages 8–22 years) and Brigham and Women's Hospital (BWH) with 70 healthy subjects (ages 14–54 years). In particular, we show that gender and age-related maturation differences in different age groups are preserved after harmonization, as measured using effect sizes (small, medium and large), irrespective of the test sample size. Since we use matched control subjects from different scanners to estimate scanner-specific effects, our goal in this work is also to determine the minimum number of well-matched subjects needed from each site to achieve best harmonization results. Our results indicate that at-least 16 to 18 well-matched healthy controls from each site are needed to reliably capture scanner related differences. The proposed method can thus be used for retrospective harmonization of raw dMRI data across sites despite differences in acquisition parameters, while preserving inter-subject anatomical variability.

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Comparing the potential of MEG and EEG to uncover brain tracking of speech temporal envelope

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): Florian Destoky, Morgane Philippe, Julie Bertels, Marie Verhasselt, Nicolas Coquelet, Marc Vander Ghinst, Vincent Wens, Xavier De Tiège, Mathieu Bourguignon

Abstract

During connected speech listening, brain activity tracks speech rhythmicity at delta (∼0.5 Hz) and theta (4–8 Hz) frequencies. Here, we compared the potential of magnetoencephalography (MEG) and high-density electroencephalography (EEG) to uncover such speech brain tracking.

Ten healthy right-handed adults listened to two different 5-min audio recordings, either without noise or mixed with a cocktail-party noise of equal loudness. Their brain activity was simultaneously recorded with MEG and EEG. We quantified speech brain tracking channel-by-channel using coherence, and with all channels at once by speech temporal envelope reconstruction accuracy.

In both conditions, speech brain tracking was significant at delta and theta frequencies and peaked in the temporal regions with both modalities (MEG and EEG). However, in the absence of noise, speech brain tracking estimated from MEG data was significantly higher than that obtained from EEG. Furthemore, to uncover significant speech brain tracking, recordings needed to be ∼3 times longer in EEG than MEG, depending on the frequency considered (delta or theta) and the estimation method. In the presence of noise, both EEG and MEG recordings replicated the previous finding that speech brain tracking at delta frequencies is stronger with attended speech (i.e., the sound subjects are attending to) than with the global sound (i.e., the attended speech and the noise combined). Other previously reported MEG findings were replicated based on MEG but not EEG recordings: 1) speech brain tracking at theta frequencies is stronger with attended speech than with the global sound, 2) speech brain tracking at delta frequencies is stronger in noiseless than noisy conditions, and 3) when noise is added, speech brain tracking at delta frequencies dampens less in the left hemisphere than in the right hemisphere. Finally, sources of speech brain tracking reconstructed from EEG data were systematically deeper and more posterior than those derived from MEG.

The present study demonstrates that speech brain tracking is better seen with MEG than EEG. Quantitatively, EEG recordings need to be ∼3 times longer than MEG recordings to uncover significant speech brain tracking. As a consequence, MEG appears more suited than EEG to pinpoint subtle effects related to speech brain tracking in a given recording time.

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Comparing the potential of MEG and EEG to uncover brain tracking of speech temporal envelope

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): Florian Destoky, Morgane Philippe, Julie Bertels, Marie Verhasselt, Nicolas Coquelet, Marc Vander Ghinst, Vincent Wens, Xavier De Tiège, Mathieu Bourguignon

Abstract

During connected speech listening, brain activity tracks speech rhythmicity at delta (∼0.5 Hz) and theta (4–8 Hz) frequencies. Here, we compared the potential of magnetoencephalography (MEG) and high-density electroencephalography (EEG) to uncover such speech brain tracking.

Ten healthy right-handed adults listened to two different 5-min audio recordings, either without noise or mixed with a cocktail-party noise of equal loudness. Their brain activity was simultaneously recorded with MEG and EEG. We quantified speech brain tracking channel-by-channel using coherence, and with all channels at once by speech temporal envelope reconstruction accuracy.

In both conditions, speech brain tracking was significant at delta and theta frequencies and peaked in the temporal regions with both modalities (MEG and EEG). However, in the absence of noise, speech brain tracking estimated from MEG data was significantly higher than that obtained from EEG. Furthemore, to uncover significant speech brain tracking, recordings needed to be ∼3 times longer in EEG than MEG, depending on the frequency considered (delta or theta) and the estimation method. In the presence of noise, both EEG and MEG recordings replicated the previous finding that speech brain tracking at delta frequencies is stronger with attended speech (i.e., the sound subjects are attending to) than with the global sound (i.e., the attended speech and the noise combined). Other previously reported MEG findings were replicated based on MEG but not EEG recordings: 1) speech brain tracking at theta frequencies is stronger with attended speech than with the global sound, 2) speech brain tracking at delta frequencies is stronger in noiseless than noisy conditions, and 3) when noise is added, speech brain tracking at delta frequencies dampens less in the left hemisphere than in the right hemisphere. Finally, sources of speech brain tracking reconstructed from EEG data were systematically deeper and more posterior than those derived from MEG.

The present study demonstrates that speech brain tracking is better seen with MEG than EEG. Quantitatively, EEG recordings need to be ∼3 times longer than MEG recordings to uncover significant speech brain tracking. As a consequence, MEG appears more suited than EEG to pinpoint subtle effects related to speech brain tracking in a given recording time.

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Resting-state white matter-cortical connectivity in non-human primate brain

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): Tung-Lin Wu, Feng Wang, Muwei Li, Kurt G. Schilling, Yurui Gao, Adam W. Anderson, Li Min Chen, Zhaohua Ding, John C. Gore

Abstract

Numerous studies have used functional magnetic resonance imaging (fMRI) to characterize functional connectivity between cortical regions by analyzing correlations in blood oxygenation level dependent (BOLD) signals in a resting state. However, to date, there have been only a handful of studies reporting resting state BOLD signals in white matter. Nonetheless, a growing number of reports has emerged in recent years suggesting white matter BOLD signals can be reliably detected, though their biophysical origins remain unclear. Moreover, recent studies have identified robust correlations in a resting state between signals from cortex and specific white matter tracts. In order to further validate and interpret these findings, we studied a non-human primate model to investigate resting-state connectivity patterns between parcellated cortical volumes and specific white matter bundles. Our results show that resting-state connectivity patterns between white and gray matter structures are not randomly distributed but share notable similarities with diffusion- and histology-derived anatomic connectivities. This suggests that resting-state BOLD correlations between white matter fiber tracts and the gray matter regions to which they connect are directly related to the anatomic arrangement and density of WM fibers. We also measured how different levels of baseline neural activity, induced by varying levels of anesthesia, modulate these patterns. As anesthesia levels were raised, we observed weakened correlation coefficients between specific white matter tracts and gray matter regions while key features of the connectivity pattern remained similar. Overall, results from this study provide further evidence that neural activity is detectable by BOLD fMRI in both gray and white matter throughout the resting brain. The combined use of gray and white matter functional connectivity could also offer refined full-scale functional parcellation of the entire brain to characterize its functional architecture.

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Resting-state white matter-cortical connectivity in non-human primate brain

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): Tung-Lin Wu, Feng Wang, Muwei Li, Kurt G. Schilling, Yurui Gao, Adam W. Anderson, Li Min Chen, Zhaohua Ding, John C. Gore

Abstract

Numerous studies have used functional magnetic resonance imaging (fMRI) to characterize functional connectivity between cortical regions by analyzing correlations in blood oxygenation level dependent (BOLD) signals in a resting state. However, to date, there have been only a handful of studies reporting resting state BOLD signals in white matter. Nonetheless, a growing number of reports has emerged in recent years suggesting white matter BOLD signals can be reliably detected, though their biophysical origins remain unclear. Moreover, recent studies have identified robust correlations in a resting state between signals from cortex and specific white matter tracts. In order to further validate and interpret these findings, we studied a non-human primate model to investigate resting-state connectivity patterns between parcellated cortical volumes and specific white matter bundles. Our results show that resting-state connectivity patterns between white and gray matter structures are not randomly distributed but share notable similarities with diffusion- and histology-derived anatomic connectivities. This suggests that resting-state BOLD correlations between white matter fiber tracts and the gray matter regions to which they connect are directly related to the anatomic arrangement and density of WM fibers. We also measured how different levels of baseline neural activity, induced by varying levels of anesthesia, modulate these patterns. As anesthesia levels were raised, we observed weakened correlation coefficients between specific white matter tracts and gray matter regions while key features of the connectivity pattern remained similar. Overall, results from this study provide further evidence that neural activity is detectable by BOLD fMRI in both gray and white matter throughout the resting brain. The combined use of gray and white matter functional connectivity could also offer refined full-scale functional parcellation of the entire brain to characterize its functional architecture.

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The BOLD response in primary motor cortex and supplementary motor area during kinesthetic motor imagery based graded fMRI neurofeedback

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): David M.A. Mehler, Angharad N. Williams, Florian Krause, Michael Lührs, Richard G. Wise, Duncan L. Turner, David E.J. Linden, Joseph R. Whittaker

Abstract

There is increasing interest in exploring the use of functional MRI neurofeedback (fMRI-NF) as a therapeutic technique for a range of neurological conditions such as stroke and Parkinson's disease (PD). One main therapeutic potential of fMRI-NF is to enhance volitional control of damaged or dysfunctional neural nodes and networks via a closed-loop feedback model using mental imagery as the catalyst of self-regulation. The choice of target node/network and direction of regulation (increase or decrease activity) are central design considerations in fMRI-NF studies. Whilst it remains unclear whether the primary motor cortex (M1) can be activated during motor imagery, the supplementary motor area (SMA) has been robustly activated during motor imagery. Such differences in the regulation potential between primary and supplementary motor cortex are important because these areas can be differentially affected by a stroke or PD, and the choice of fMRI-NF target and grade of self-regulation of activity likely have substantial influence on the clinical effects and cost effectiveness of NF-based interventions. In this study we therefore investigated firstly whether healthy subjects would be able to achieve self-regulation of the hand-representation areas of M1 and the SMA using fMRI-NF training. There was a significant decrease in M1 neural activity during fMRI-NF, whereas SMA neural activity was increased, albeit not with the predicated graded effect. This study has important implications for fMRI-NF protocols that employ motor imagery to modulate activity in specific target regions of the brain and to determine how they may be tailored for neurorehabilitation.

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The BOLD response in primary motor cortex and supplementary motor area during kinesthetic motor imagery based graded fMRI neurofeedback

Publication date: Available online 8 September 2018

Source: NeuroImage

Author(s): David M.A. Mehler, Angharad N. Williams, Florian Krause, Michael Lührs, Richard G. Wise, Duncan L. Turner, David E.J. Linden, Joseph R. Whittaker

Abstract

There is increasing interest in exploring the use of functional MRI neurofeedback (fMRI-NF) as a therapeutic technique for a range of neurological conditions such as stroke and Parkinson's disease (PD). One main therapeutic potential of fMRI-NF is to enhance volitional control of damaged or dysfunctional neural nodes and networks via a closed-loop feedback model using mental imagery as the catalyst of self-regulation. The choice of target node/network and direction of regulation (increase or decrease activity) are central design considerations in fMRI-NF studies. Whilst it remains unclear whether the primary motor cortex (M1) can be activated during motor imagery, the supplementary motor area (SMA) has been robustly activated during motor imagery. Such differences in the regulation potential between primary and supplementary motor cortex are important because these areas can be differentially affected by a stroke or PD, and the choice of fMRI-NF target and grade of self-regulation of activity likely have substantial influence on the clinical effects and cost effectiveness of NF-based interventions. In this study we therefore investigated firstly whether healthy subjects would be able to achieve self-regulation of the hand-representation areas of M1 and the SMA using fMRI-NF training. There was a significant decrease in M1 neural activity during fMRI-NF, whereas SMA neural activity was increased, albeit not with the predicated graded effect. This study has important implications for fMRI-NF protocols that employ motor imagery to modulate activity in specific target regions of the brain and to determine how they may be tailored for neurorehabilitation.

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The effects of breastfeeding versus formula-feeding on cerebral cortex maturation in infant rhesus macaques

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Zheng Liu, Martha Neuringer, John W. Erdman, Matthew J. Kuchan, Lauren Renner, Emily E. Johnson, Xiaojie Wang, Christopher D. Kroenke

Abstract

Breastfeeding is positively associated with several outcomes reflecting early brain development and cognitive functioning. Brain neuroimaging studies have shown that exclusively breastfed children have increased white matter and subcortical gray matter volume compared to formula-fed children. However, it is difficult to disentangle the effects of nutrition in breast milk from other confounding factors that affect brain development, particularly in studies of human subjects. Among the nutrients provided by human breast milk are the carotenoid lutein and the natural form of tocopherol, both of which are selectively deposited in brain. Lutein is the predominant carotenoid in breast milk but not in most infant formulas, whereas infant formulas are supplemented with the synthetic form of tocopherol. In this study, a non-human primate model was used to investigate the effects of breastfeeding versus formula-feeding, as well as lutein and natural RRR-α-tocopherol supplementation of infant formula, on brain maturation under controlled experimental conditions. Infant rhesus macaques (Macaca mulatta) were exclusively breastfed, or were fed infant formulas with different levels and sources of lutein and α-tocopherol. Of note, the breastfed group were mother-reared whereas the formula-fed infants were nursery-reared. Brain structural and diffusion MR images were collected, and brain T₂ was measured, at two, four and six months of age. The mother-reared breastfed group was observed to differ from the formula-fed groups by possessing higher diffusion fractional anisotropy (FA) in the corpus callosum, and lower FA in the cerebral cortex at four and six months of age. Cortical regions exhibiting the largest differences include primary motor, premotor, lateral prefrontal, and inferior temporal cortices. No differences were found between the formula groups. Although this study did not identify a nutritional component of breast milk that could be provided to infant formula to facilitate brain maturation consistent with that observed in breastfed animals, our findings indicate that breastfeeding promoted maturation of the corpus callosum and cerebral cortical gray matter in the absence of several confounding factors that affect studies in human infants. However, differences in rearing experience remain as a potential contributor to brain structural differences between breastfed and formula fed infants.

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The effects of breastfeeding versus formula-feeding on cerebral cortex maturation in infant rhesus macaques

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Zheng Liu, Martha Neuringer, John W. Erdman, Matthew J. Kuchan, Lauren Renner, Emily E. Johnson, Xiaojie Wang, Christopher D. Kroenke

Abstract

Breastfeeding is positively associated with several outcomes reflecting early brain development and cognitive functioning. Brain neuroimaging studies have shown that exclusively breastfed children have increased white matter and subcortical gray matter volume compared to formula-fed children. However, it is difficult to disentangle the effects of nutrition in breast milk from other confounding factors that affect brain development, particularly in studies of human subjects. Among the nutrients provided by human breast milk are the carotenoid lutein and the natural form of tocopherol, both of which are selectively deposited in brain. Lutein is the predominant carotenoid in breast milk but not in most infant formulas, whereas infant formulas are supplemented with the synthetic form of tocopherol. In this study, a non-human primate model was used to investigate the effects of breastfeeding versus formula-feeding, as well as lutein and natural RRR-α-tocopherol supplementation of infant formula, on brain maturation under controlled experimental conditions. Infant rhesus macaques (Macaca mulatta) were exclusively breastfed, or were fed infant formulas with different levels and sources of lutein and α-tocopherol. Of note, the breastfed group were mother-reared whereas the formula-fed infants were nursery-reared. Brain structural and diffusion MR images were collected, and brain T₂ was measured, at two, four and six months of age. The mother-reared breastfed group was observed to differ from the formula-fed groups by possessing higher diffusion fractional anisotropy (FA) in the corpus callosum, and lower FA in the cerebral cortex at four and six months of age. Cortical regions exhibiting the largest differences include primary motor, premotor, lateral prefrontal, and inferior temporal cortices. No differences were found between the formula groups. Although this study did not identify a nutritional component of breast milk that could be provided to infant formula to facilitate brain maturation consistent with that observed in breastfed animals, our findings indicate that breastfeeding promoted maturation of the corpus callosum and cerebral cortical gray matter in the absence of several confounding factors that affect studies in human infants. However, differences in rearing experience remain as a potential contributor to brain structural differences between breastfed and formula fed infants.

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Inhibitory and excitatory mechanisms in the human cingulate-cortex support reinforcement learning: A functional Proton Magnetic Resonance Spectroscopy study

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Vered Bezalel, Rony Paz, Assaf Tal

Abstract

The dorsal anterior cingulate cortex (dACC) is crucial for motivation, reward- and error-guided decision-making, yet its excitatory and inhibitory mechanisms remain poorly explored in humans. In particular, the balance between excitation and inhibition (E/I), demonstrated to play a role in animal studies, is difficult to measure in behaving humans. Here, we used functional magnetic-resonance-spectroscopy (¹H-fMRS) to measure the brain's major inhibitory (GABA) and excitatory (Glutamate) neurotransmitters during reinforcement learning with three different conditions: high cognitive load (uncertainty); probabilistic discrimination learning; and a control null-condition. Participants learned to prefer the gain option in the discrimination phase and had no preference in the other conditions. We found increased GABA levels during the uncertainty condition, potentially reflecting recruitment of inhibitory systems during high cognitive load when trying to learn. Further, higher GABA levels during the null (baseline) condition correlated with improved discrimination learning. Finally, glutamate and GABA levels were correlated during high cognitive load. These results suggest that availability of dACC inhibitory resources enables successful learning. Our approach helps elucidate the potential contribution of the balance between excitation and inhibition to learning and motivation in behaving humans.

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Inhibitory and excitatory mechanisms in the human cingulate-cortex support reinforcement learning: A functional Proton Magnetic Resonance Spectroscopy study

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Vered Bezalel, Rony Paz, Assaf Tal

Abstract

The dorsal anterior cingulate cortex (dACC) is crucial for motivation, reward- and error-guided decision-making, yet its excitatory and inhibitory mechanisms remain poorly explored in humans. In particular, the balance between excitation and inhibition (E/I), demonstrated to play a role in animal studies, is difficult to measure in behaving humans. Here, we used functional magnetic-resonance-spectroscopy (¹H-fMRS) to measure the brain's major inhibitory (GABA) and excitatory (Glutamate) neurotransmitters during reinforcement learning with three different conditions: high cognitive load (uncertainty); probabilistic discrimination learning; and a control null-condition. Participants learned to prefer the gain option in the discrimination phase and had no preference in the other conditions. We found increased GABA levels during the uncertainty condition, potentially reflecting recruitment of inhibitory systems during high cognitive load when trying to learn. Further, higher GABA levels during the null (baseline) condition correlated with improved discrimination learning. Finally, glutamate and GABA levels were correlated during high cognitive load. These results suggest that availability of dACC inhibitory resources enables successful learning. Our approach helps elucidate the potential contribution of the balance between excitation and inhibition to learning and motivation in behaving humans.

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Error-related modulations of the sensorimotor post-movement and foreperiod beta-band activities arise from distinct neural substrates and do not reflect efferent signal processing

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Julie Alayrangues, Flavie Torrecillos, Amirhossein Jahani, Nicole Malfait

Abstract

While beta activity has been extensively studied in relation to voluntary movement, its role in sensorimotor adaptation remains largely uncertain. Recently, it has been shown that the post-movement beta rebound as well as beta activity during movement-preparation are modulated by movement errors. However, there are critical functional differences between pre- and post-movement beta activities. Here, we addressed two related open questions. Do the pre- and post-movement error-related modulations arise from distinct neural substrates? Do these modulations relate to efferent signals shaping muscle-activation patterns or do they reflect integration of sensory information, intervening upstream of the motor output? For this purpose, first we exploited independent component analysis (ICA) which revealed a double dissociation suggesting that distinct neural substrates are recruited in error-related beta-power modulations observed before and after movement. Second, we compared error-related beta oscillation responses observed in two bimanual reaching tasks involving similar movements but different interlimb coordination, and in which the same mechanical perturbations induced different behavioral adaptive responses. While the task difference was not reflected in the post-movement beta rebound, the pre-movement beta activity was differently modulated according to the interlimb coordination. Critically, we show an uncoupling between the behavioral and the electrophysiological responses during the movement preparation phase, which demonstrates that the error-related modulation of the foreperiod beta activity does not reflect changes in the motor output from primary motor cortex. It seems instead to relate to higher level processing of sensory afferents, essential for sensorimotor adaptation.

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Error-related modulations of the sensorimotor post-movement and foreperiod beta-band activities arise from distinct neural substrates and do not reflect efferent signal processing

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Julie Alayrangues, Flavie Torrecillos, Amirhossein Jahani, Nicole Malfait

Abstract

While beta activity has been extensively studied in relation to voluntary movement, its role in sensorimotor adaptation remains largely uncertain. Recently, it has been shown that the post-movement beta rebound as well as beta activity during movement-preparation are modulated by movement errors. However, there are critical functional differences between pre- and post-movement beta activities. Here, we addressed two related open questions. Do the pre- and post-movement error-related modulations arise from distinct neural substrates? Do these modulations relate to efferent signals shaping muscle-activation patterns or do they reflect integration of sensory information, intervening upstream of the motor output? For this purpose, first we exploited independent component analysis (ICA) which revealed a double dissociation suggesting that distinct neural substrates are recruited in error-related beta-power modulations observed before and after movement. Second, we compared error-related beta oscillation responses observed in two bimanual reaching tasks involving similar movements but different interlimb coordination, and in which the same mechanical perturbations induced different behavioral adaptive responses. While the task difference was not reflected in the post-movement beta rebound, the pre-movement beta activity was differently modulated according to the interlimb coordination. Critically, we show an uncoupling between the behavioral and the electrophysiological responses during the movement preparation phase, which demonstrates that the error-related modulation of the foreperiod beta activity does not reflect changes in the motor output from primary motor cortex. It seems instead to relate to higher level processing of sensory afferents, essential for sensorimotor adaptation.

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A comparative fMRI meta-analysis of altruistic and strategic decisions to give

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Jo Cutler, Daniel Campbell-Meiklejohn

The decision to share resources is fundamental for cohesive societies. Humans can be motivated to give for many reasons. Some generosity incurs a definite cost, with no extrinsic reward to the act, but instead provides intrinsic satisfaction (labelled here as 'altruistic' giving). Other giving behaviours are done with the prospect of improving one's own situation via reciprocity, reputation, or public good (labelled here as 'strategic' giving). These contexts differ in the source, certainty, and timing of rewards as well as the inferences made about others' mental states. We executed a combined statistical map and coordinate-based fMRI meta-analysis of decisions to give (36 studies, 1150 participants). Methods included a novel approach for accommodating variable signal dropout between studies in meta-analysis. Results reveal consistent, cross-paradigm neural correlates of each decision type, commonalities, and informative differences. Relative to being selfish, altruistic and strategic giving activate overlapping reward networks. However, strategic decisions showed greater activity in striatal regions than altruistic choices. Altruistic giving, more than strategic, activated subgenual anterior cingulate cortex (sgACC). Ventromedial prefrontal cortex (vmPFC) is consistently involved during generous decisions and processing across a posterior to anterior axis differentiates the altruistic/strategic context. Posterior vmPFC was preferentially recruited during altruistic decisions. Regions of the 'social brain' showed distinct patterns of activity between choice types, reflecting the different use of theory of mind in the two contexts. We provide the consistent neural correlates of decisions to give, and show that many will depend on the source of incentives.

Graphical abstract

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A comparative fMRI meta-analysis of altruistic and strategic decisions to give

Publication date: Available online 7 September 2018

Source: NeuroImage

Author(s): Jo Cutler, Daniel Campbell-Meiklejohn

The decision to share resources is fundamental for cohesive societies. Humans can be motivated to give for many reasons. Some generosity incurs a definite cost, with no extrinsic reward to the act, but instead provides intrinsic satisfaction (labelled here as 'altruistic' giving). Other giving behaviours are done with the prospect of improving one's own situation via reciprocity, reputation, or public good (labelled here as 'strategic' giving). These contexts differ in the source, certainty, and timing of rewards as well as the inferences made about others' mental states. We executed a combined statistical map and coordinate-based fMRI meta-analysis of decisions to give (36 studies, 1150 participants). Methods included a novel approach for accommodating variable signal dropout between studies in meta-analysis. Results reveal consistent, cross-paradigm neural correlates of each decision type, commonalities, and informative differences. Relative to being selfish, altruistic and strategic giving activate overlapping reward networks. However, strategic decisions showed greater activity in striatal regions than altruistic choices. Altruistic giving, more than strategic, activated subgenual anterior cingulate cortex (sgACC). Ventromedial prefrontal cortex (vmPFC) is consistently involved during generous decisions and processing across a posterior to anterior axis differentiates the altruistic/strategic context. Posterior vmPFC was preferentially recruited during altruistic decisions. Regions of the 'social brain' showed distinct patterns of activity between choice types, reflecting the different use of theory of mind in the two contexts. We provide the consistent neural correlates of decisions to give, and show that many will depend on the source of incentives.

Graphical abstract

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Alteration of functional brain architecture in 22q11.2 deletion syndrome – Insights into susceptibility for psychosis

Publication date: Available online 5 September 2018

Source: NeuroImage

Author(s): Kit Melissa Larsen, Ilvana Dzafic, Hartwig Roman Siebner, Marta Isabel Garrido

Abstract

The 22q11.2 deletion is one of the most common copy number variants in humans. Carriers of the deletion have a markedly increased risk for neurodevelopmental brain disorders, including schizophrenia, autism spectrum disorders, and attention deficit hyperactivity disorder. The high risk of psychiatric disorders associated with 22q11.2 deletion syndrome offers a unique possibility to identify the functional abnormalities that precede the emergence of psychosis. Carriers of a 22q11.2 deletion show a broad range of sensory processing and cognitive abnormalities similar as in schizophrenia, such as auditory and visual sensory processing, response inhibition, working memory, social cognition, reward processing and arithmetic processing. All these processes have a significant negative impact on daily life if impaired and have been studied extensively in schizophrenia using task-based functional neuroimaging. Here, we review task-related functional brain mapping studies that have used electroencephalography or functional magnetic resonance imaging to identify functional alterations in carriers with 22q11.2 deletion syndrome within the above mentioned cognitive and sensory domains. We discuss how the identification of functional changes at the brain system level can advance the general understanding of which neurobiological alterations set the frame for the emergence of neurodevelopmental disorders in the human brain. The task-based functional neuroimaging literature shows conflicting results in many domains. Nevertheless, consistent similarities between 22q11.2 deletion syndrome and schizophrenia have been found for sensory processing, social cognition and working memory. We discuss these functional brain alterations in terms of potential biomarkers of increased risk for psychosis in the general population.

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Sparse wars: A survey and comparative study of spherical deconvolution algorithms for diffusion MRI

Publication date: Available online 5 September 2018

Source: NeuroImage

Author(s): Erick Jorge Canales-Rodríguez, Jon Haitz Legarreta, Marco Pizzolato, Gaëtan Rensonnet, Gabriel Girard, Jonathan Rafael Patiño, Muhamed Barakovic, David Romascano, Yasser Alemán-Gomez, Joaquim Radua, Edith Pomarol-Clotet, Raymond Salvador, Jean-Philippe Thiran, Alessandro Daducci

Abstract

Spherical deconvolution methods are widely used to estimate the brain's white-matter fiber orientations from diffusion MRI data. In this study, eight spherical deconvolution algorithms were implemented and evaluated. These included two model selection techniques based on the extended Bayesian information criterion (i.e., best subset selection and the least absolute shrinkage and selection operator), iteratively reweighted l₂-and l₁-norm approaches to approximate the l₀-norm, sparse Bayesian learning, Cauchy deconvolution, and two accelerated Richardson-Lucy algorithms. Results from our exhaustive evaluation show that there is no single optimal method for all different fiber configurations, suggesting that further studies should be conducted to find the optimal way of combining solutions from different methods. We found l₀-norm regularization algorithms to resolve more accurately fiber crossings with small inter-fiber angles. However, in voxels with very dominant fibers, algorithms promoting more sparsity are less accurate in detecting smaller fibers. In most cases, the best algorithm to reconstruct fiber crossings with two fibers did not perform optimally in voxels with one or three fibers. Therefore, simplified validation systems as employed in a number of previous studies, where only two fibers with similar volume fractions were tested, should be avoided as they provide incomplete information. Future studies proposing new reconstruction methods based on high angular resolution diffusion imaging data should validate their results by considering, at least, voxels with one, two, and three fibers, as well as voxels with dominant fibers and different diffusion anisotropies.

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Sparse wars: A survey and comparative study of spherical deconvolution algorithms for diffusion MRI

Publication date: Available online 5 September 2018

Source: NeuroImage

Author(s): Erick Jorge Canales-Rodríguez, Jon Haitz Legarreta, Marco Pizzolato, Gaëtan Rensonnet, Gabriel Girard, Jonathan Rafael Patiño, Muhamed Barakovic, David Romascano, Yasser Alemán-Gomez, Joaquim Radua, Edith Pomarol-Clotet, Raymond Salvador, Jean-Philippe Thiran, Alessandro Daducci

Abstract

Spherical deconvolution methods are widely used to estimate the brain's white-matter fiber orientations from diffusion MRI data. In this study, eight spherical deconvolution algorithms were implemented and evaluated. These included two model selection techniques based on the extended Bayesian information criterion (i.e., best subset selection and the least absolute shrinkage and selection operator), iteratively reweighted l₂-and l₁-norm approaches to approximate the l₀-norm, sparse Bayesian learning, Cauchy deconvolution, and two accelerated Richardson-Lucy algorithms. Results from our exhaustive evaluation show that there is no single optimal method for all different fiber configurations, suggesting that further studies should be conducted to find the optimal way of combining solutions from different methods. We found l₀-norm regularization algorithms to resolve more accurately fiber crossings with small inter-fiber angles. However, in voxels with very dominant fibers, algorithms promoting more sparsity are less accurate in detecting smaller fibers. In most cases, the best algorithm to reconstruct fiber crossings with two fibers did not perform optimally in voxels with one or three fibers. Therefore, simplified validation systems as employed in a number of previous studies, where only two fibers with similar volume fractions were tested, should be avoided as they provide incomplete information. Future studies proposing new reconstruction methods based on high angular resolution diffusion imaging data should validate their results by considering, at least, voxels with one, two, and three fibers, as well as voxels with dominant fibers and different diffusion anisotropies.

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Lead-DBS v2: Towards a comprehensive pipeline for deep brain stimulation imaging

Publication date: Available online 1 September 2018

Source: NeuroImage

Author(s): Andreas Horn, Ningfei Li, Till A. Dembek, Ari Kappel, Chadwick Boulay, Siobhan Ewert, Anna Tietze, Andreas Husch, Thushara Perera, Wolf-Julian Neumann, Marco Reisert, Hang Si, Robert Oostenveld, Christopher Rorden, Fang-Cheng Yeh, Qianqian Fang, Todd M. Herrington, Johannes Vorwerk, Andrea A. Kühn

Abstract

Deep brain stimulation (DBS) is a highly efficacious treatment option for movement disorders and a growing number of other indications are investigated in clinical trials. To ensure optimal treatment outcome, exact electrode placement is required. Moreover, to analyze the relationship between electrode location and clinical results, a precise reconstruction of electrode placement is required, posing specific challenges to the field of neuroimaging. Since 2014 the open source toolbox Lead-DBS is available, which aims at facilitating this process. The tool has since become a popular platform for DBS imaging. With support of a broad community of researchers worldwide, methods have been continuously updated and complemented by new tools for tasks such as multispectral nonlinear registration, structural/functional connectivity analyses, brain shift correction, reconstruction of microelectrode recordings and orientation detection of segmented DBS leads. The rapid development and emergence of these methods in DBS data analysis require us to revisit and revise the pipelines introduced in the original methods publication.

Here we demonstrate the updated DBS and connectome pipelines of Lead-DBS using a single patient example with state-of-the-art high-field imaging as well as a retrospective cohort of patients scanned in a typical clinical setting at 1.5T. Imaging data of the 3T example patient is co-registered using five algorithms and nonlinearly warped into template space using ten approaches for comparative purposes. After reconstruction of DBS electrodes (which is possible using three methods and a specific refinement tool), the volume of tissue activated is calculated for two DBS settings using four distinct models and various parameters. Finally, four whole-brain tractography algorithms are applied to the patient's preoperative diffusion MRI data and structural as well as functional connectivity between the stimulation volume and other brain areas are estimated using a total of eight approaches and datasets. In addition, we demonstrate impact of selected preprocessing strategies on the retrospective sample of 51 PD patients. We compare the amount of variance in clinical improvement that can be explained by the computer model depending on the method of choice.

This work represents a multi-institutional collaborative effort to develop a comprehensive, open source pipeline for DBS imaging and connectomics, which has already empowered several studies, and may facilitate a variety of future studies in the field.

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Lead-DBS v2: Towards a comprehensive pipeline for deep brain stimulation imaging

Publication date: Available online 1 September 2018

Source: NeuroImage

Author(s): Andreas Horn, Ningfei Li, Till A. Dembek, Ari Kappel, Chadwick Boulay, Siobhan Ewert, Anna Tietze, Andreas Husch, Thushara Perera, Wolf-Julian Neumann, Marco Reisert, Hang Si, Robert Oostenveld, Christopher Rorden, Fang-Cheng Yeh, Qianqian Fang, Todd M. Herrington, Johannes Vorwerk, Andrea A. Kühn

Abstract

Deep brain stimulation (DBS) is a highly efficacious treatment option for movement disorders and a growing number of other indications are investigated in clinical trials. To ensure optimal treatment outcome, exact electrode placement is required. Moreover, to analyze the relationship between electrode location and clinical results, a precise reconstruction of electrode placement is required, posing specific challenges to the field of neuroimaging. Since 2014 the open source toolbox Lead-DBS is available, which aims at facilitating this process. The tool has since become a popular platform for DBS imaging. With support of a broad community of researchers worldwide, methods have been continuously updated and complemented by new tools for tasks such as multispectral nonlinear registration, structural/functional connectivity analyses, brain shift correction, reconstruction of microelectrode recordings and orientation detection of segmented DBS leads. The rapid development and emergence of these methods in DBS data analysis require us to revisit and revise the pipelines introduced in the original methods publication.

Here we demonstrate the updated DBS and connectome pipelines of Lead-DBS using a single patient example with state-of-the-art high-field imaging as well as a retrospective cohort of patients scanned in a typical clinical setting at 1.5T. Imaging data of the 3T example patient is co-registered using five algorithms and nonlinearly warped into template space using ten approaches for comparative purposes. After reconstruction of DBS electrodes (which is possible using three methods and a specific refinement tool), the volume of tissue activated is calculated for two DBS settings using four distinct models and various parameters. Finally, four whole-brain tractography algorithms are applied to the patient's preoperative diffusion MRI data and structural as well as functional connectivity between the stimulation volume and other brain areas are estimated using a total of eight approaches and datasets. In addition, we demonstrate impact of selected preprocessing strategies on the retrospective sample of 51 PD patients. We compare the amount of variance in clinical improvement that can be explained by the computer model depending on the method of choice.

This work represents a multi-institutional collaborative effort to develop a comprehensive, open source pipeline for DBS imaging and connectomics, which has already empowered several studies, and may facilitate a variety of future studies in the field.

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A novel noise filtered and occlusion removal: navigational accuracy in augmented reality-based constructive jaw surgery

Abstract

Purpose

Augmented reality-based constructive jaw surgery has been facing various limitations such as noise in real-time images, the navigational error of implants and jaw, image overlay error, and occlusion handling which have limited the implementation of augmented reality (AR) in corrective jaw surgery. This research aimed to improve the navigational accuracy, through noise and occlusion removal, during positioning of an implant in relation to the jaw bone to be cut or drilled.

Method

The proposed system consists of a weighting-based de-noising filter and depth mapping-based occlusion removal for removing any occluded object such as surgical tools, the surgeon's body parts, and blood.

Results

The maxillary (upper jaw) and mandibular (lower jaw) jaw bone sample results show that the proposed method can achieve the image overlay error (video accuracy) of 0.23~0.35 mm and processing time of 8–12 frames per second compared to 0.35~0.45 mm and 6–11 frames per second by the existing best system.

Conclusion

The proposed system concentrates on removing the noise from the real-time video frame and the occlusion. Thus, the acceptable range of accuracy and the processing time are provided by this study for surgeons for carrying out a smooth surgical flow.

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Audiologist-led screening of acoustic neuromas in patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus: our experience in 1126 patients.

Audiologist-led screening of acoustic neuromas in patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus: our experience in 1126 patients.

J Laryngol Otol. 2018 Sep 10;:1-4

Authors: Abbas Y, Smith G, Trinidade A

Abstract
OBJECTIVE: To determine whether patients within an otolaryngology department presenting with asymmetrical sensorineural hearing loss and/or unilateral tinnitus can be safely and cost-efficiently screened for acoustic neuroma by audiologists as a first or only point of contact.
METHODS: A prospective case series and cost analysis were conducted at a tertiary referral centre. Between April 2013 and March 2017, 1126 adult patients presented to the audiology department with asymmetrical sensorineural hearing loss and/or unilateral tinnitus. All were screened for acoustic neuroma with magnetic resonance imaging, based on pre-determined criteria. The main outcome measure was the presence of acoustic neuroma or other pathology on magnetic resonance imaging.
RESULTS: Twenty-five patients (2.22 per cent) were found to have an acoustic neuroma (size range: 3-20 mm) and were referred to the otolaryngologist for further assessment. The remaining patients were appropriately managed and discharged by the audiologists without ENT input. This resulted in an overall cost saving of £164 850.
CONCLUSION: Patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus can be safely screened for acoustic neuroma and independently managed by audiologists as a first or only point of contact, resulting in considerable departmental cost savings.

PMID: 30198461 [PubMed - as supplied by publisher]

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Audiologist-led screening of acoustic neuromas in patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus: our experience in 1126 patients.

Audiologist-led screening of acoustic neuromas in patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus: our experience in 1126 patients.

J Laryngol Otol. 2018 Sep 10;:1-4

Authors: Abbas Y, Smith G, Trinidade A

Abstract
OBJECTIVE: To determine whether patients within an otolaryngology department presenting with asymmetrical sensorineural hearing loss and/or unilateral tinnitus can be safely and cost-efficiently screened for acoustic neuroma by audiologists as a first or only point of contact.
METHODS: A prospective case series and cost analysis were conducted at a tertiary referral centre. Between April 2013 and March 2017, 1126 adult patients presented to the audiology department with asymmetrical sensorineural hearing loss and/or unilateral tinnitus. All were screened for acoustic neuroma with magnetic resonance imaging, based on pre-determined criteria. The main outcome measure was the presence of acoustic neuroma or other pathology on magnetic resonance imaging.
RESULTS: Twenty-five patients (2.22 per cent) were found to have an acoustic neuroma (size range: 3-20 mm) and were referred to the otolaryngologist for further assessment. The remaining patients were appropriately managed and discharged by the audiologists without ENT input. This resulted in an overall cost saving of £164 850.
CONCLUSION: Patients with asymmetrical sensorineural hearing loss and/or unilateral tinnitus can be safely screened for acoustic neuroma and independently managed by audiologists as a first or only point of contact, resulting in considerable departmental cost savings.

PMID: 30198461 [PubMed - as supplied by publisher]

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Stapedotomy using a 4 mm endoscope: any advantage over a microscope?

Stapedotomy using a 4 mm endoscope: any advantage over a microscope?

J Laryngol Otol. 2018 Sep 10;:1-5

Authors: Bhardwaj A, Anant A, Bharadwaj N, Gupta A, Gupta S

Abstract
OBJECTIVES: To ascertain the feasibility of endoscopic (4 mm) stapedotomy, and compare intra- and post-operative variations with microscopic stapedotomies.
METHODS: Forty otosclerosis patients were scheduled for microscopic or endoscopic stapedotomy. Intra-operative variables compared were: incision, canalplasty, canal wall curettage for ossicular assessment, chorda tympani manipulation, ability to perform stapes footplate perforation before its supra-structure removal, and operative time. Post-operative variables compared were ear pain and hearing improvement.
RESULTS: Of the 20 microscopy patients, 4 required endaural incision and canalplasty because of canal overhangs, and 7 required canal wall curettage for ossicular assessment. None of the 20 endoscopy patients required these procedures. Chorda tympani was manipulated in 13 and 6 patients in the microscopy and endoscopy groups respectively, while the stapes footplate could be perforated in 5 and 11 patients respectively. Mean operative time was 50.25 and 76.05 minutes in the microscopy and endoscopy groups respectively. In the endoscopy group, mean air-bone gap was 37.12 and 10.73 dB pre- and post-operation respectively; in the microscopy group, these values were 35.95 and 13.81 dB.
CONCLUSION: Endoscopic stapedotomy has comparable hearing outcomes. Sinonasal endoscope serves as a better tool for: minimal incision, canalplasty avoidance, less chorda tympani mobilisation, and stapes footplate perforation ability.

PMID: 30198460 [PubMed - as supplied by publisher]

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Stapedotomy using a 4 mm endoscope: any advantage over a microscope?

Stapedotomy using a 4 mm endoscope: any advantage over a microscope?

J Laryngol Otol. 2018 Sep 10;:1-5

Authors: Bhardwaj A, Anant A, Bharadwaj N, Gupta A, Gupta S

Abstract
OBJECTIVES: To ascertain the feasibility of endoscopic (4 mm) stapedotomy, and compare intra- and post-operative variations with microscopic stapedotomies.
METHODS: Forty otosclerosis patients were scheduled for microscopic or endoscopic stapedotomy. Intra-operative variables compared were: incision, canalplasty, canal wall curettage for ossicular assessment, chorda tympani manipulation, ability to perform stapes footplate perforation before its supra-structure removal, and operative time. Post-operative variables compared were ear pain and hearing improvement.
RESULTS: Of the 20 microscopy patients, 4 required endaural incision and canalplasty because of canal overhangs, and 7 required canal wall curettage for ossicular assessment. None of the 20 endoscopy patients required these procedures. Chorda tympani was manipulated in 13 and 6 patients in the microscopy and endoscopy groups respectively, while the stapes footplate could be perforated in 5 and 11 patients respectively. Mean operative time was 50.25 and 76.05 minutes in the microscopy and endoscopy groups respectively. In the endoscopy group, mean air-bone gap was 37.12 and 10.73 dB pre- and post-operation respectively; in the microscopy group, these values were 35.95 and 13.81 dB.
CONCLUSION: Endoscopic stapedotomy has comparable hearing outcomes. Sinonasal endoscope serves as a better tool for: minimal incision, canalplasty avoidance, less chorda tympani mobilisation, and stapes footplate perforation ability.

PMID: 30198460 [PubMed - as supplied by publisher]

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9/11 first responders begin to feel attack's long-term health effects

9/11 first responders begin to feel attack's long-term health effects  NBCNews.comFull coverage

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'A cesspool of cancer' - 17 years on from 9/11, illnesses still abound

'A cesspool of cancer' - 17 years on from 9/11, illnesses still abound  The GuardianFull coverage

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Papillary Thyroid Cancer Pipeline Therapeutics Assessment, 2018

Papillary Thyroid Cancer Pipeline Therapeutics Assessment, 2018  indsutryjournal.comFull coverage

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Papillary Thyroid Cancer Pipeline Therapeutics Assessment, 2018

Papillary Thyroid Cancer Pipeline Therapeutics Assessment, 2018  indsutryjournal.comFull coverage

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Percutaneous ozone nucleolysis for lumbar disc herniation

Abstract

Purpose

All percutaneous minimally invasive disc treatments are typically indicated to contained disc herniations. Our study's aim is to evaluate prospectively the efficacy of ozone nucleolysis in the treatment of either contained or uncontained lumbar disc herniations.

Methods

Fifty-two patients, aged 27–87 years, with symptomatic herniated lumbar discs, without migration, sequestration, or severe degenerative disc changes, who failed conservative treatment, were included in our study. The patients underwent fluoroscopic-guided intradiscal oxygen-ozone mixture injection (5 ml) at a concentration of 27–30 μg/ml and periradicular injection of the same O₂-O₃ mixture (10 ml), steroid (1 ml), and local anesthetic (1 ml). Clinical outcomes were evaluated, based on the Oswestry Disability Index (ODI) and pain intensity (0–5) scale results, obtained initially and at 2- and 6-month controls. Our results were analyzed by ANOVA and chi-squared (χ²) tests.

Results

Our initial results obtained at 2-month control were promising, indicating a significant decrease in pain disability and intensity in 74% (37) and 76% (38) of the patients respectively, and minimally increased to 76% (38) and 78% (39) at 6-month control (P < 0.001 and CI 99.9%). The mean preprocedure ODI and pain intensity scores were 35 ± 14.36 and 2.38 ± 0.90, respectively, which were reduced to 19.36 ± 13.12 and 1.04 ± 0.92 at 6-month control. Our failure had been mostly related to long symptoms duration of more than 1 year. No complications were recorded.

Conclusion

Ozone nucleolysis is a safe cost-effective minimally invasive technique for treatment of contained and uncontained lumbar disc herniations.

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Percutaneous ozone nucleolysis for lumbar disc herniation

Abstract

Purpose

All percutaneous minimally invasive disc treatments are typically indicated to contained disc herniations. Our study's aim is to evaluate prospectively the efficacy of ozone nucleolysis in the treatment of either contained or uncontained lumbar disc herniations.

Methods

Fifty-two patients, aged 27–87 years, with symptomatic herniated lumbar discs, without migration, sequestration, or severe degenerative disc changes, who failed conservative treatment, were included in our study. The patients underwent fluoroscopic-guided intradiscal oxygen-ozone mixture injection (5 ml) at a concentration of 27–30 μg/ml and periradicular injection of the same O₂-O₃ mixture (10 ml), steroid (1 ml), and local anesthetic (1 ml). Clinical outcomes were evaluated, based on the Oswestry Disability Index (ODI) and pain intensity (0–5) scale results, obtained initially and at 2- and 6-month controls. Our results were analyzed by ANOVA and chi-squared (χ²) tests.

Results

Our initial results obtained at 2-month control were promising, indicating a significant decrease in pain disability and intensity in 74% (37) and 76% (38) of the patients respectively, and minimally increased to 76% (38) and 78% (39) at 6-month control (P < 0.001 and CI 99.9%). The mean preprocedure ODI and pain intensity scores were 35 ± 14.36 and 2.38 ± 0.90, respectively, which were reduced to 19.36 ± 13.12 and 1.04 ± 0.92 at 6-month control. Our failure had been mostly related to long symptoms duration of more than 1 year. No complications were recorded.

Conclusion

Ozone nucleolysis is a safe cost-effective minimally invasive technique for treatment of contained and uncontained lumbar disc herniations.

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Food Allergies Caused by Allergenic Lipid Transfer Proteins: What Is behind the Geographic Restriction?

Abstract

Purpose of Review

To critically examine evidence suggesting that food allergy induced by lipid transfer proteins (LTPs) follows a geographic pattern.

Recent Findings

LTP syndrome remains most common in the Mediterranean basin, with a clear gradient seen in prevalence of LTP sensitization between northern and southern Europe. We hypothesize that high levels of birch pollen seem to protect against LTP allergy, as these higher levels correlate with a lower prevalence of LTP hypersensitivity. Nevertheless, LTP food allergy cases still appear in areas having a high environmental level of birch pollen.

Summary

Food allergy caused by LTP may be related to (1) primary sensitization to a food LTP allergen in the absence of pollinosis, (2) primary sensitization to LTP from a pollen source, and (3) co-sensitization to LTP from pollen and food.

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Food Allergies Caused by Allergenic Lipid Transfer Proteins: What Is behind the Geographic Restriction?

Abstract

Purpose of Review

To critically examine evidence suggesting that food allergy induced by lipid transfer proteins (LTPs) follows a geographic pattern.

Recent Findings

LTP syndrome remains most common in the Mediterranean basin, with a clear gradient seen in prevalence of LTP sensitization between northern and southern Europe. We hypothesize that high levels of birch pollen seem to protect against LTP allergy, as these higher levels correlate with a lower prevalence of LTP hypersensitivity. Nevertheless, LTP food allergy cases still appear in areas having a high environmental level of birch pollen.

Summary

Food allergy caused by LTP may be related to (1) primary sensitization to a food LTP allergen in the absence of pollinosis, (2) primary sensitization to LTP from a pollen source, and (3) co-sensitization to LTP from pollen and food.

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Initial presentation of human papillomavirus-related head and neck cancer: A retrospective review

Initial presentation of human papillomavirus-related head and neck cancer: A retrospective review  MD LinxFull coverage

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Initial presentation of human papillomavirus-related head and neck cancer: A retrospective review

Initial presentation of human papillomavirus-related head and neck cancer: A retrospective review  MD LinxFull coverage

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Demographic predictors of head and neck cancer survival differ in the elderly

Demographic predictors of head and neck cancer survival differ in the elderly  MD LinxFull coverage

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Demographic predictors of head and neck cancer survival differ in the elderly

Demographic predictors of head and neck cancer survival differ in the elderly  MD LinxFull coverage

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How SLPs Can Foster Bilingual Skills in Students on the Autism Spectrum

In a recent online chat, SLP and bilingual researcher Betty Yu shares strategies for encouraging students and families to communicate in their heritage language. Participant: Is there ever an age or circumstance where you feel it is too late to start exposing a child to their heritage language? Betty Yu: It's never too late to start learning one's heritage language. Just as it's never too late to learn any additional language. A common occurrence in the U.S. is people start seriously learning (or re-learning) their heritage languages as adults, often in college, once they're mature enough to understand the benefits. Every family makes decisions about their language use and what they're going to pass on to their children in different ways, and for very personal...

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How SLPs Can Foster Bilingual Skills in Students on the Autism Spectrum

In a recent online chat, SLP and bilingual researcher Betty Yu shares strategies for encouraging students and families to communicate in their heritage language. Participant: Is there ever an age or circumstance where you feel it is too late to start exposing a child to their heritage language? Betty Yu: It's never too late to start learning one's heritage language. Just as it's never too late to learn any additional language. A common occurrence in the U.S. is people start seriously learning (or re-learning) their heritage languages as adults, often in college, once they're mature enough to understand the benefits. Every family makes decisions about their language use and what they're going to pass on to their children in different ways, and for very personal...

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Market of Choice Issues Allergy Alert for Undeclared Egg in Sesame Noodle Salad Vegan

Market of Choice, based in Eugene, Ore., is recalling its Gourmet Take Away Sesame Noodle Salad Vegan, because it contains undeclared egg. People who have an allergy or severe sensitivity to egg run the risk of serious or life-threatening allergic reactions if they consume this product. (Source: Food and Drug Administration)

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Market of Choice Issues Allergy Alert for Undeclared Egg in Sesame Noodle Salad Vegan

Market of Choice, based in Eugene, Ore., is recalling its Gourmet Take Away Sesame Noodle Salad Vegan, because it contains undeclared egg. People who have an allergy or severe sensitivity to egg run the risk of serious or life-threatening allergic reactions if they consume this product. (Source: Food and Drug Administration)

MedWorm Message: Have you tried our new medical search engine? More powerful than before. Log on with your social media account. 100% free.

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Market of Choice Issues Allergy Alert for Undeclared Egg in Sesame Noodle Salad Vegan

Market of Choice, based in Eugene, Ore., is recalling its Gourmet Take Away Sesame Noodle Salad Vegan, because it contains undeclared egg. People who have an allergy or severe sensitivity to egg run the risk of serious or life-threatening allergic reactions if they consume this product. (Source: Food and Drug Administration)

MedWorm Message: Have you tried our new medical search engine? More powerful than before. Log on with your social media account. 100% free.

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Market of Choice Issues Allergy Alert for Undeclared Egg in Sesame Noodle Salad Vegan

Market of Choice, based in Eugene, Ore., is recalling its Gourmet Take Away Sesame Noodle Salad Vegan, because it contains undeclared egg. People who have an allergy or severe sensitivity to egg run the risk of serious or life-threatening allergic reactions if they consume this product. (Source: Food and Drug Administration)

MedWorm Message: Have you tried our new medical search engine? More powerful than before. Log on with your social media account. 100% free.

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Rheumatoid nodule‐like cutaneous granuloma associated with RAG1‐deficient severe combined immunodeficiency: a rare case

Journal of Cutaneous Pathology, Volume 0, Issue ja, -Not available-.


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Rheumatoid nodule‐like cutaneous granuloma associated with RAG1‐deficient severe combined immunodeficiency: a rare case

Journal of Cutaneous Pathology, Volume 0, Issue ja, -Not available-.


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Diagnostic Accuracy of Dysphonia Classification of DSI and AVQI

The Laryngoscope, EarlyView.


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Diagnostic Accuracy of Dysphonia Classification of DSI and AVQI

The Laryngoscope, EarlyView.


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How SLPs Can Foster Bilingual Skills in Students on the Autism Spectrum

In a recent online chat, SLP and bilingual researcher Betty Yu shares strategies for encouraging students and families to communicate in their heritage language. Participant: Is there ever an age or circumstance where you feel it is too late to start exposing a child to their heritage language? Betty Yu: It's never too late to start learning one's heritage language. Just as it's never too late to learn any additional language. A common occurrence in the U.S. is people start seriously learning (or re-learning) their heritage languages as adults, often in college, once they're mature enough to understand the benefits. Every family makes decisions about their language use and what they're going to pass on to their children in different ways, and for very personal...

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader https://ift.tt/2CExtN0

How SLPs Can Foster Bilingual Skills in Students on the Autism Spectrum

In a recent online chat, SLP and bilingual researcher Betty Yu shares strategies for encouraging students and families to communicate in their heritage language. Participant: Is there ever an age or circumstance where you feel it is too late to start exposing a child to their heritage language? Betty Yu: It's never too late to start learning one's heritage language. Just as it's never too late to learn any additional language. A common occurrence in the U.S. is people start seriously learning (or re-learning) their heritage languages as adults, often in college, once they're mature enough to understand the benefits. Every family makes decisions about their language use and what they're going to pass on to their children in different ways, and for very personal...

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Food Allergies Caused by Allergenic Lipid Transfer Proteins: What Is behind the Geographic Restriction?

Abstract

Purpose of Review

To critically examine evidence suggesting that food allergy induced by lipid transfer proteins (LTPs) follows a geographic pattern.

Recent Findings

LTP syndrome remains most common in the Mediterranean basin, with a clear gradient seen in prevalence of LTP sensitization between northern and southern Europe. We hypothesize that high levels of birch pollen seem to protect against LTP allergy, as these higher levels correlate with a lower prevalence of LTP hypersensitivity. Nevertheless, LTP food allergy cases still appear in areas having a high environmental level of birch pollen.

Summary

Food allergy caused by LTP may be related to (1) primary sensitization to a food LTP allergen in the absence of pollinosis, (2) primary sensitization to LTP from a pollen source, and (3) co-sensitization to LTP from pollen and food.

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Relationship between sella turcica bridging and cephalometric parameters in adolescents and young adults

Abstract

Objectives

Sella turcica bridging occurs with fusion or calcification of the anterior and posterior clinoid processes in the middle cranial region. This study aimed to compare the cephalometric parameters among normal shape, partial bridge, and total bridge of the sella turcica in adolescent and young adult subjects.

Methods

This retrospective study was performed on the lateral cephalometric radiographs of 410 Turkish adolescent and young adult subjects. The subjects were divided into three groups: normal sella turcica shape (128 females, 32 males; mean age: 17.7 ± 1.54 years), partial sella turcica bridge (129 females, 32 males; mean age: 17.8 ± 2.15 years), and total sella turcica bridge (66 females, 23 males; mean age: 18.2 ± 1.82 years). Thirteen angular and eight linear cephalometric measurements were performed using a cephalometric software program. The data were analyzed by one-way analysis of variance, and the Kruskal–Wallis test with the Bonferroni correction.

Results

Significant differences were found for Nperp–A distance, Nperp–Pg distance, and palatal plane-to-anterior cranial base angle among the groups (p < 0.016). There were no significant differences in the cephalometric parameters between the partial and total sella turcica bridging groups (p > 0.05).

Conclusions

This study evaluated a large amount of data for cephalometric measurements focusing on the degree of calcification of the sella turcica in adolescent and young adult subjects. The maxilla and mandible were located in a sagittally retrusive position in the partial and total sella turcica bridge subjects compared with the normal sella turcica shape subjects.

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Food Allergies Caused by Allergenic Lipid Transfer Proteins: What Is behind the Geographic Restriction?

Abstract

Purpose of Review

To critically examine evidence suggesting that food allergy induced by lipid transfer proteins (LTPs) follows a geographic pattern.

Recent Findings

LTP syndrome remains most common in the Mediterranean basin, with a clear gradient seen in prevalence of LTP sensitization between northern and southern Europe. We hypothesize that high levels of birch pollen seem to protect against LTP allergy, as these higher levels correlate with a lower prevalence of LTP hypersensitivity. Nevertheless, LTP food allergy cases still appear in areas having a high environmental level of birch pollen.

Summary

Food allergy caused by LTP may be related to (1) primary sensitization to a food LTP allergen in the absence of pollinosis, (2) primary sensitization to LTP from a pollen source, and (3) co-sensitization to LTP from pollen and food.

from #Head and Neck by Sfakianakis via simeraentaxei on Inoreader https://ift.tt/2x4UZN1

Relationship between sella turcica bridging and cephalometric parameters in adolescents and young adults

Abstract

Objectives

Sella turcica bridging occurs with fusion or calcification of the anterior and posterior clinoid processes in the middle cranial region. This study aimed to compare the cephalometric parameters among normal shape, partial bridge, and total bridge of the sella turcica in adolescent and young adult subjects.

Methods

This retrospective study was performed on the lateral cephalometric radiographs of 410 Turkish adolescent and young adult subjects. The subjects were divided into three groups: normal sella turcica shape (128 females, 32 males; mean age: 17.7 ± 1.54 years), partial sella turcica bridge (129 females, 32 males; mean age: 17.8 ± 2.15 years), and total sella turcica bridge (66 females, 23 males; mean age: 18.2 ± 1.82 years). Thirteen angular and eight linear cephalometric measurements were performed using a cephalometric software program. The data were analyzed by one-way analysis of variance, and the Kruskal–Wallis test with the Bonferroni correction.

Results

Significant differences were found for Nperp–A distance, Nperp–Pg distance, and palatal plane-to-anterior cranial base angle among the groups (p < 0.016). There were no significant differences in the cephalometric parameters between the partial and total sella turcica bridging groups (p > 0.05).

Conclusions

This study evaluated a large amount of data for cephalometric measurements focusing on the degree of calcification of the sella turcica in adolescent and young adult subjects. The maxilla and mandible were located in a sagittally retrusive position in the partial and total sella turcica bridge subjects compared with the normal sella turcica shape subjects.

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Glomangiopericytoma of the Nasal Cavity with CTNNB1 p.S37C Mutation: A Case Report and Literature Review

Abstract

Glomangiopericytoma (GPC) is a rare mesenchymal tumor arising from the nasal cavity or paranasal sinuses. GPC was categorized as a borderline and low-malignant-potential tumor by the World Health Organization in 2005 and accounts for less than 0.5% of all sinonasal tumors. We report a case of GPC in a 74-year-old woman with a history of recurrent epistaxis and nasal obstruction. A reddish tumor was seen in the right nasal cavity. Enhanced computed tomography showed a mass lesion occupying the right nasal cavity. The tumor, which originated from the nasal septum in the olfactory fissure area, was resected with 5-mm mucosal margins by endoscopic sinus surgery. Histologic examination revealed a uniform proliferation of oval-to-short spindle-shaped cells beneath the epithelium. Immunohistologic analysis demonstrated the tumor cells were positive for α-smooth muscle actin, β-catenin and Vimentin, and negative for AE1/AE3, Bcl-2, CD34, CD117, Factor VIIIR Ag, S-100 protein, or STAT6. The percentage of Ki-67-positive cells was approximately 5%. Genetic analysis using next-generation sequencing revealed a missense mutation in the CTNNB1 gene (c.110C > G, p.S37C). While other CTNNB1 mutations have been described in GPC; this is the first report of this specific mutation. The mutation was confirmed using Sanger sequencing.

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Glomangiopericytoma of the Nasal Cavity with CTNNB1 p.S37C Mutation: A Case Report and Literature Review

Abstract

Glomangiopericytoma (GPC) is a rare mesenchymal tumor arising from the nasal cavity or paranasal sinuses. GPC was categorized as a borderline and low-malignant-potential tumor by the World Health Organization in 2005 and accounts for less than 0.5% of all sinonasal tumors. We report a case of GPC in a 74-year-old woman with a history of recurrent epistaxis and nasal obstruction. A reddish tumor was seen in the right nasal cavity. Enhanced computed tomography showed a mass lesion occupying the right nasal cavity. The tumor, which originated from the nasal septum in the olfactory fissure area, was resected with 5-mm mucosal margins by endoscopic sinus surgery. Histologic examination revealed a uniform proliferation of oval-to-short spindle-shaped cells beneath the epithelium. Immunohistologic analysis demonstrated the tumor cells were positive for α-smooth muscle actin, β-catenin and Vimentin, and negative for AE1/AE3, Bcl-2, CD34, CD117, Factor VIIIR Ag, S-100 protein, or STAT6. The percentage of Ki-67-positive cells was approximately 5%. Genetic analysis using next-generation sequencing revealed a missense mutation in the CTNNB1 gene (c.110C > G, p.S37C). While other CTNNB1 mutations have been described in GPC; this is the first report of this specific mutation. The mutation was confirmed using Sanger sequencing.

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Changes in the regional shape and volume of subcortical nuclei in patients with tinnitus comorbid with mild hearing loss

Abstract

Purpose

Tinnitus, the perception of sound without an external source, is a prevalent disease, but its underlying mechanism has not been fully elucidated. Recent studies have suggested the involvement of subcortical nuclei in tinnitus generation. We investigated changes in the local shape and volume of subcortical nuclei in relation to tinnitus.

Methods

The participants included 53 patients with tinnitus and 52 age- and gender-matched normal controls. Individual 3D T1-weighted structural images were obtained using 3-T magnetic resonance imaging. Surface-based vertex analysis (SVA) was performed with automated segmentation of the bilateral caudate nuclei, putamina, nucleus accumbens, thalami, pallidum, hippocampi, amygdalae, and brainstem. The scalar distances from the mean surface and volumes of 15 nuclei were compared between the tinnitus and control groups and correlated with tinnitus handicap score (THI) and tinnitus duration.

Results

SVA revealed regional contractions in the accessory basal and lateral nuclei of the right amygdala and expansions in the left medial and right ventral posterior nuclei and lateral dorsal nucleus of both thalami. The surface distances of the right nucleus accumbens were positively correlated with tinnitus duration, while those of the left nucleus accumbens and left hippocampus were negatively correlated with THI.

Conclusion

Regional atrophy of the amygdala may indicate self-modulation of emotional response regulation to diminish tinnitus-related emotional distress. Thalamic regional expansion may signify dysfunctional auditory gating in the thalamus, where inhibition of the tinnitus signal at the thalamus level is disrupted due to abnormal changes in the limbic system, ultimately leading to the tinnitus percept.

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Changes in the regional shape and volume of subcortical nuclei in patients with tinnitus comorbid with mild hearing loss

Abstract

Purpose

Tinnitus, the perception of sound without an external source, is a prevalent disease, but its underlying mechanism has not been fully elucidated. Recent studies have suggested the involvement of subcortical nuclei in tinnitus generation. We investigated changes in the local shape and volume of subcortical nuclei in relation to tinnitus.

Methods

The participants included 53 patients with tinnitus and 52 age- and gender-matched normal controls. Individual 3D T1-weighted structural images were obtained using 3-T magnetic resonance imaging. Surface-based vertex analysis (SVA) was performed with automated segmentation of the bilateral caudate nuclei, putamina, nucleus accumbens, thalami, pallidum, hippocampi, amygdalae, and brainstem. The scalar distances from the mean surface and volumes of 15 nuclei were compared between the tinnitus and control groups and correlated with tinnitus handicap score (THI) and tinnitus duration.

Results

SVA revealed regional contractions in the accessory basal and lateral nuclei of the right amygdala and expansions in the left medial and right ventral posterior nuclei and lateral dorsal nucleus of both thalami. The surface distances of the right nucleus accumbens were positively correlated with tinnitus duration, while those of the left nucleus accumbens and left hippocampus were negatively correlated with THI.

Conclusion

Regional atrophy of the amygdala may indicate self-modulation of emotional response regulation to diminish tinnitus-related emotional distress. Thalamic regional expansion may signify dysfunctional auditory gating in the thalamus, where inhibition of the tinnitus signal at the thalamus level is disrupted due to abnormal changes in the limbic system, ultimately leading to the tinnitus percept.

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Issue Information

Head &Neck, Volume 40, Issue 9, Page 1875-1878, September 2018.


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Cover Image

Head &Neck, Volume 40, Issue 9, Page C1-C1, September 2018.


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Cover Image

Head &Neck, Volume 40, Issue 9, Page C1-C1, September 2018.


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Identification and molecular characterization of allergenic nsLTP from durum wheat (Triticum turgidum)

Clinical &Experimental Allergy, Volume 0, Issue ja, -Not available-.


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Glucocorticoids ameliorate periostin‐induced tissue remodeling in chronic rhinosinusitis with nasal polyps

Clinical &Experimental Allergy, Volume 0, Issue ja, -Not available-.


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Identification and molecular characterization of allergenic nsLTP from durum wheat (Triticum turgidum)

Clinical &Experimental Allergy, Volume 0, Issue ja, -Not available-.


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Glucocorticoids ameliorate periostin‐induced tissue remodeling in chronic rhinosinusitis with nasal polyps

Clinical &Experimental Allergy, Volume 0, Issue ja, -Not available-.


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Insurers unlikely to greet return of asbestos with open arms

Insurers unlikely to greet return of asbestos with open arms  Business InsuranceFull coverage

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Insurers unlikely to greet return of asbestos with open arms

Insurers unlikely to greet return of asbestos with open arms  Business InsuranceFull coverage

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How much alcohol is too much? Bad news for Red Wine Day

How much alcohol is too much? Bad news for Red Wine Day  OregonLive.comFull coverage

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How much alcohol is too much? Bad news for Red Wine Day

How much alcohol is too much? Bad news for Red Wine Day  OregonLive.comFull coverage

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Camrelizumab for nasopharyngeal carcinoma: a new hope?

Camrelizumab for nasopharyngeal carcinoma: a new hope?  The LancetFull coverage

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Camrelizumab for nasopharyngeal carcinoma: a new hope?

Camrelizumab for nasopharyngeal carcinoma: a new hope?  The LancetFull coverage

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Topical steroid vs placebo for the prevention of radiation dermatitis in head and neck cancer patients receiving ...

Topical steroid vs placebo for the prevention of radiation dermatitis in head and neck cancer patients receiving ...  MD LinxFull coverage

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