Faculty Bibliography

Cochlear implant (CI) recipients have difficulty understanding speech in noise even at moderate signal-to-noise ratios. Knowing the mechanisms they use to understand speech in noise may facilitate the search for better speech processing algorithms. In the present study, a computational model is used to assess whether CI users' vowel identification in noise can be explained by formant frequency cues (F1 and F2). Vowel identification was tested with 12 unilateral CI users in quiet and in noise. Formant cues were measured from vowels in each condition, specific to each subject's speech processor. Noise distorted the location of vowels in the F2 vs F1 plane in comparison to quiet. The best fit model to subjects' data in quiet produced model predictions in noise that were within 8% of actual scores on average. Predictions in noise were much better when assuming that subjects used a priori knowledge regarding how formant information is degraded in noise (experiment 1). However, the model's best fit to subjects' confusion matrices in noise was worse than in quiet, suggesting that CI users utilize formant cues to identify vowels in noise, but to a different extent than how they identify vowels in quiet (experiment 2).

Craniofacial surgeons perform operations that involve exposure of the dura. Typical procedures include cranial vault remodeling (CVR), fronto-orbital advancement (FOA), Le Fort III, monobloc, bipartition advancement, or distraction. Cerebrospinal fluid (CSF) fistulas remain one of the most common complications encountered, occurring in up to 30% of patients. Cerebrospinal fluid fistulas can be encountered intraoperatively, acutely, or in the late postoperative period. Traditional management has been well described in the neurosurgical literature. While several studies of complications exist, there is a relative lack of adequate information for craniofacial surgeons. The authors review current literature and provide 3 patients to illustrate our management paradigm.The authors review 30 years of experience at our institution and the pertinent literature. The mean rate of CSF fistula was 11.2%; rates were lowest for FOA/CVR, 5.5%. Patients with fistulas persisting after 2 days of conservative therapy or whom were symptomatic prompted placement of a lumbar subarachnoid catheter. Failure of the leak to resolve with CSF diversion prompted exploration and therapy which could include a patch, pericranial flap, and/or endonasal repair with septal flaps. Three patients are used to illustrate the paradigm, all of which have had no recurrence thus far.Cerebrospinal fluid fistula remains one of most common complications craniofacial surgeons encounter. Although neurosurgeons are often part of the clinical team, the craniofacial surgeon should be familiar with all aspects of treatment. Prompt diagnosis and appropriate knowledgeable management may avoid morbidity and mortality.

Monopolar Virtual Channels (MPVCs) use current steering to increase the number of spectral channels provided to cochlear implant users beyond the physical number of electrodes. The current spread created with a current steered channel is similar to the spread found for monopolar stimulation, and this spread may be one of the bottlenecks for improved performance with an increased number of channels. Quadrupolar Virtual Channels (QPVCs) use current focusing in combination with steering in an attempt to increase the number of channels while reducing channel interaction. However, due to the potentially asymmetric current field generated by QPVCs, there may be distortions in the place pitch representation using this mode. A Virtual Tripole (VTP) is introduced as a current focused virtual channel with a relatively symmetrical electric field distribution. In this study, we looked at pitch ranking in cochlear implant users with QPVC, VTP, and MPVC configurations to determine if place pitch shifts similarly across the cochlea or if any of the stimulation modes shift non-monotonically. Results suggest that MPVC and VTP stimulation provide a consistent monotonic shift across cochlear positions while the place shift provided by QPVCs was more variable. The use of VTP stimulation would be recommended instead of QPVC for a speech processing strategy.

Objective Given the recalcitrant nature of recurrent respiratory papillomatosis, targeted therapies to reduce disease burden are fundamental to improved patient care paradigms. We seek to demonstrate the safety of imiquimod injection into vocal fold mucosa by evaluating the degree of laryngeal edema, histopathologic changes to vocal fold structure, and serologic interferon alpha (IFNalpha) levels following injection. Study Design Preclinical. Setting Academic institution. Subjects and Methods Six New Zealand White rabbits underwent unilateral injection of 100 microg of sterile imiquimod (1 microg/microL), with 100 microL of normal saline injected into the contralateral vocal fold. Direct laryngoscopy was performed on days 3, 7, and 30 following injection. Larynges from 3 rabbits were harvested on postinjection day 7 for histologic analysis. The remaining 3 rabbit larynges were harvested on day 30. Serial serum samples were drawn for IFNalpha quantification via immunoassay. Results No signs of respiratory distress were observed at any point. Vocal fold appearance was not clinically divergent between imiquimod and control conditions via serial direct laryngoscopic evaluation. No inflammatory lesions or scarring were identified following injection. Histology showed no signs of acute inflammatory processes or changes in the control or imiquimod injection groups. Serum IFNalpha increased at days 3 and 7 following imiquimod injection ( P < .0001 and P = .0368, respectively), before returning to baseline by day 14. Conclusions Vocal fold imiquimod injection did not result in notable morbidity in this preclinical model. However, serum IFNalpha concentrations increased transiently. These data are critical to advance the therapeutic utility of this compound, particularly in the setting of recurrent respiratory papillomatosis.

OBJECTIVE: To characterize the performance plateau after unilateral cochlear implantation (CI) in prelingually and postlingually deafened adults and to compare their relative progress. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Prelingually and postlingually deaf adults who received a unilateral CI and completed a minimum of 2 years of follow-up at our center. INTERVENTION: Unilateral CI. MAIN OUTCOME MEASURES:: Standard speech perception testing (consonant-nucleus-consonant [CNC] monosyllabic word test and hearing in noise test [HINT] or AzBio sentence test) were performed preoperatively and 3 and 12 months postoperatively, and annually thereafter. RESULTS: In postlingually deaf patients (n = 102), there was a significant improvement in word scores for 3 years postimplantation (p < 0.01). Beyond the 3 years postoperative time point, word scores continued to improve, albeit at a flatter rate. In prelingually deaf patients (n = 16) word scores improved significantly for 5 years postimplantation (p = 0.03). CONCLUSIONS: Adults with postlingual deafness undergoing unilateral CI show significant improvement in speech perception for 3 years postimplantation, at which point their performance continues to improve, albeit at a flatter rate. The performance of adults with prelingual deafness improves significantly as late as 5 years postimplantation. These time intervals reflect a change to the currently reported 6 to 12 months period and should impact on counseling, especially in the prelingual CI candidate.

Significant technological advances have fostered a movement toward minimally invasive surgical interventions for the management of ventral skull base malignancies. The care of patients with these lesions ideally involves an interdisciplinary skull base team that includes otolaryngologists, neurologic surgeons, radiation oncologists, and medical oncologists. This overview describes considerations essential for diagnosis, prognosis, and preoperative evaluation. Furthermore, surgical nuances, strategies for skull base reconstruction, and nonsurgical options are briefly discussed. Our hope is that this overview may be useful as an up-to-date description of the challenging clinical scenarios associated with these lesions.

While cerebral amyloid angiopathy is a common cause of lobar hemorrhage, rarely it may be associated with an inflammatory response, thought to be incited by amyloid deposits. We report a 73-year-old woman with an extensive cancer history who presented with tumor-like lesions and symptoms of homonymous hemianopia and prosopagnosia. Found to have cerebral amyloid angiopathy-related inflammation proven by brain biopsy, she was treated successfully with immunosuppression.

Behavioural engagement can enhance sensory perception. However, the neuronal mechanisms by which behavioural states affect stimulus perception remain poorly understood. Here we record from single units in auditory cortex of rats performing a self-initiated go/no-go auditory task. Self-initiation transforms cortical tuning curves and bidirectionally modulates stimulus-evoked activity patterns and improves auditory detection and recognition. Trial self-initiation decreases the rate of spontaneous activity in the majority of recorded cells. Optogenetic disruption of cortical activity before and during tone presentation shows that these changes in evoked and spontaneous activity are important for sound perception. Thus, behavioural engagement can prepare cortical circuits for sensory processing by dynamically changing sound representation and by controlling the pattern of spontaneous activity.

Objective Rhinoplasty, a surgical procedure that alters the shape or appearance of the nose while preserving or enhancing the nasal airway, ranks among the most commonly performed cosmetic procedures in the United States, with >200,000 procedures reported in 2014. While it is difficult to calculate the exact economic burden incurred by rhinoplasty patients following surgery with or without complications, the average rhinoplasty procedure typically exceeds $4000. The costs incurred due to complications, infections, or revision surgery may include the cost of long-term antibiotics, hospitalization, or lost revenue from hours/days of missed work. The resultant psychological impact of rhinoplasty can also be significant. Furthermore, the health care burden from psychological pressures of nasal deformities/aesthetic shortcomings, surgical infections, surgical pain, side effects from antibiotics, and nasal packing materials must also be considered for these patients. Prior to this guideline, limited literature existed on standard care considerations for pre- and postsurgical management and for standard surgical practice to ensure optimal outcomes for patients undergoing rhinoplasty. The impetus for this guideline is to utilize current evidence-based medicine practices and data to build unanimity regarding the peri- and postoperative strategies to maximize patient safety and to optimize surgical results for patients. Purpose The primary purpose of this guideline executive summary is to provide evidence-based recommendations for clinicians who either perform rhinoplasty or are involved in the care of a rhinoplasty candidate, as well as to optimize patient care, promote effective diagnosis and therapy, and reduce harmful or unnecessary variations in care. The target audience is any clinician or individual, in any setting, involved in the management of these patients. The target patient population is all patients aged >/=15 years. The guideline is intended to focus on knowledge gaps, practice variations, and clinical concerns associated with this surgical procedure; it is not intended to be a comprehensive reference for improving nasal form and function after rhinoplasty. Recommendations in this guideline concerning education and counseling to the patient are intended to include the caregiver if the patient is <18 years of age. Action Statements The Guideline Development Group made the following recommendations: (1) Clinicians should ask all patients seeking rhinoplasty about their motivations for surgery and their expectations for outcomes, should provide feedback on whether those expectations are a realistic goal of surgery, and should document this discussion in the medical record. (2) Clinicians should assess rhinoplasty candidates for comorbid conditions that could modify or contraindicate surgery, including obstructive sleep apnea, body dysmorphic disorder, bleeding disorders, or chronic use of topical vasoconstrictive intranasal drugs. (3) The surgeon, or the surgeon's designee, should evaluate the rhinoplasty candidate for nasal airway obstruction during the preoperative assessment. (4) The surgeon, or the surgeon's designee, should educate rhinoplasty candidates regarding what to expect after surgery, how surgery might affect the ability to breathe through the nose, potential complications of surgery, and the possible need for future nasal surgery. (5) The clinician, or the clinician's designee, should counsel rhinoplasty candidates with documented obstructive sleep apnea about the impact of surgery on nasal airway obstruction and how obstructive sleep apnea might affect perioperative management. (6) The surgeon, or the surgeon's designee, should educate rhinoplasty patients before surgery about strategies to manage discomfort after surgery. (7) Clinicians should document patient satisfaction with their nasal appearance and with their nasal function at a minimum of 12 months after rhinoplasty. The guideline development group made recommendations against certain actions: (1) When a surgeon, or the surgeon's designee, chooses to administer perioperative antibiotics for rhinoplasty, he or she should not routinely prescribe antibiotic therapy for a duration >24 hours after surgery. (2) Surgeons should not routinely place packing in the nasal cavity of rhinoplasty patients (with or without septoplasty) at the conclusion of surgery. The panel group made the following statement an option: (1) The surgeon, or the surgeon's designee, may administer perioperative systemic steroids to the rhinoplasty patient.

OBJECTIVE: High channel count electrode arrays allow for the monitoring of large-scale neural activity at high spatial resolution. Implantable arrays featuring many recording sites require compact, high bandwidth front-end electronics. In the present study, we investigated the use of a small, light weight, and low cost digital current-sensing integrated circuit for acquiring cortical surface signals from a 61-channel micro-electrocorticographic (ECoG) array. APPROACH: We recorded both acute and chronic ECoG signal from rat auditory cortex using our novel digital current-sensing headstage. For direct comparison, separate recordings were made in the same anesthetized preparations using an analog voltage headstage. A model of electrode impedance explained the transformation between current- and voltage-sensed signals, and was used to reconstruct cortical potential. We evaluated the digital headstage using several metrics of the baseline and response signals. MAIN RESULTS: The digital current headstage recorded neural signal with similar spatiotemporal stastics and auditory frequency tuning compared to the voltage signal. The signal-to-noise ratio of auditory evoked responses (AERs) was significantly stronger in the current signal. Stimulus decoding based on true and reconstructed voltage signals were not significantly different. Recordings from an implanted system showed AERs that were detectable and decodable for 52 days. The reconstruction filter mitigated the thermal current noise of the electrode impedance and enhanced overall SNR. SIGNIFICANCE: We developed and validated a novel approach to headstage acquisition that used current-input circuits to independently digitize 61 channels of ECoG measurements of the cortical field. These low-cost circuits, intended to measure photo-currents in digital imaging, not only provided a signal representing the local cortical field with virtually the same sensitivity and specificity as a traditional voltage headstage but also resulted in a small, light headstage that can easily be scaled to record from hundreds of channels.