Faculty Bibliography

Sensory cortices contain extensive descending (corticofugal) pathways, yet their impact on brainstem processing - particularly across sensory systems - remains poorly understood. In the auditory system, the inferior colliculus (IC) in the midbrain receives cross-modal inputs from the visual cortex (VC). However, the influences from VC on auditory midbrain processing are unclear. To investigate whether and how visual cortical inputs affect IC auditory responses, the present study combines auditory blood-oxygenation-level-dependent (BOLD) functional MRI (fMRI) with cell-type specific optogenetic manipulation of visual cortex. The results show that predominant optogenetic excitation of the excitatory pyramidal neurons in the infragranular layers of the primary VC enhances the noise-evoked BOLD fMRI responses within the IC. This finding reveals that inputs from VC influence and facilitate basic sound processing in the auditory midbrain. Such combined optogenetic and auditory fMRI approach can shed light on the large-scale modulatory effects of corticofugal pathways and guide detailed electrophysiological studies in the future.

Sensory deprivation during development induces lifelong changes to central nervous system function that are associated with perceptual impairments. However, the relationship between neural and behavioral deficits is uncertain due to a lack of simultaneous measurements during task performance. Therefore, we telemetrically recorded from auditory cortex neurons in gerbils reared with developmental conductive hearing loss as they performed an auditory task in which rapid fluctuations in amplitude are detected. These data were compared to a measure of auditory brainstem temporal processing from each animal. We found that developmental HL diminished behavioral performance, but did not alter brainstem temporal processing. However, the simultaneous assessment of neural and behavioral processing revealed that perceptual deficits were associated with a degraded cortical population code that could be explained by greater trial-to-trial response variability. Our findings suggest that the perceptual limitations that attend early hearing loss are best explained by an encoding deficit in auditory cortex.

OBJECTIVE:Analysis of the efficacy of sphenopalatine artery (SPA) and internal maxillary artery (IMAX) ligation within the pterygopalatine fossa to control posterior epistaxis. METHODS:Demographic and clinical data were collected in sixty-two consecutive patients who had SPA/IMAX ligation surgery. Clinical outcomes such as re-bleed rates and complications were acquired. RESULTS:A total of 62 patients were studied. Thirty-eight percent of patients had previously undergone silver nitrate nasal cautery for epistaxis. Nine patients had undergone previous attempt of SPA procedure or embolization in other services. Two patients returned to the operating room for anterior ethmoid ligation. There was one mortality within 30 days of surgery. Follow up ranged from 3 months to 56 months (median= 28 months). CONCLUSIONS:Dual SPA and IMAX ligation is effective in the control of difficult epistaxis cases, even in those patients with prior surgical intervention.

BACKGROUND:Postoperative chemoradiotherapy (CRT) is considered standard of care in patients with locally advanced head and neck cancer with positive margins and/or extracapsular extension (ECE). METHODS:The National Cancer Data Base (NCDB) was queried to identify patients with squamous cell carcinoma of the head and neck with stages III to IVB disease or with positive margins and/or ECE diagnosed between 2004 and 2012 receiving postoperative radiotherapy (RT). Using univariable and multivariable logistic and Cox regression, we assessed for predictors of CRT use and covariables impacting overall survival (OS), including in a propensity-matched subset. RESULTS:Of 12 224 patients, 67.1% with positive margins and/or ECE received CRT as well as 54.0% without positive margins and/or ECE. The 5-year OS was 61.6% for RT alone versus 67.4% for CRT. In the propensity-matched cohort, OS benefit persisted with CRT, including in a subset with positive margins and/or ECE but not without. CONCLUSION/CONCLUSIONS:Postoperative CRT seems underutilized with positive margins and/or ECE and overutilized without positive margins and/or ECE. The CRT was associated with improved OS but the benefit persisted only in the subset with positive margins and/or ECE.

Stimulation pulse rate affects current amplitude discrimination by cochlear implant (CI) users, indicated by the evidence that the JND (just noticeable difference) in current amplitude delivered by a CI electrode becomes larger at higher pulse rates. However, it is not clearly understood whether pulse rate would affect discrimination of speech intensities presented acoustically to CI processors, or what the size of this effect might be. Intensity discrimination depends on two factors: the growth of loudness with increasing sound intensity and the loudness JND (or the just noticeable loudness increment). This study evaluated the hypothesis that stimulation pulse rate affects loudness JND. This was done by measuring current amplitude JNDs in an experiment design based on signal detection theory according to which loudness discrimination is related to internal noise (which is manifested by variability in loudness percept in response to repetitions of the same physical stimulus). Current amplitude JNDs were measured for equally loud pulse trains of 500 and 3000 pps (pulses per second) by increasing the current amplitude of the target pulse train until it was perceived just louder than a same-rate or different-rate reference pulse train. The JND measures were obtained at two presentation levels. At the louder level, the current amplitude JNDs were affected by the rate of the reference pulse train in a way that was consistent with greater noise or variability in loudness perception for the higher pulse rate. The results suggest that increasing pulse rate from 500 to 3000 pps can increase loudness JND by 60 % at the upper portion of the dynamic range. This is equivalent to a 38 % reduction in the number of discriminable steps for acoustic and speech intensities.

OBJECTIVE:Technological change is leading to an evolution in medical education. The objective of our study was to assess the impact of a medical knowledge app, called PulseQD, on resident education within our otolaryngology-head and neck surgery department at Montefiore Medical Center, Albert Einstein College of Medicine (Bronx, NY). METHODS:A prospective cohort study was conducted within the Department of Otolaryngology-Head and Neck Surgery from July 2016 to June 2017. All faculty attendings and residents were asked to participate in the study and were included. A Web and mobile-based app, PulseQD, that allowed for collaborative learning was implemented. Questionnaires were given at the beginning and end of the academic year. Otolaryngology Training Exam (OTE) scores were collected RESULTS: A total of 20 residents and 13 faculty members participated in the study. Residents used online sources of medical information significantly more often than faculty (90% and 54%, respectively, P = 0.0179). Residents and faculty felt that PulseQD offered a valuable perspective on clinically relevant medical information (P = 0.0003), was a great way to test clinical and medical knowledge (P = 0.0001), and improved the sharing and discussing of medical knowledge (P < 0.0001). There was a statistically significant 5.8% improvement in OTE scores (P = 0.0008) at the end of the academic year. CONCLUSION/CONCLUSIONS:The implementation of a novel mobile app, PulseQD, was well received by residents and faculty in the Department of Otolaryngology-Head and Neck Surgery. Preliminary data suggest that app-based learning may lead to improved performance on knowledge-based assessments. LEVEL OF EVIDENCE/METHODS:NA. Laryngoscope, 2017.