Faculty Bibliography

BACKGROUND: The relationship between nasal airway function and sleep-disordered breathing (SDB) remains unclear. Although correction of nasal obstruction can significantly improve nighttime breathing in some patients, nasal obstruction may not play a role in all cases of SDB. An effective method of stratifying these patients is needed. Acoustic rhinometry (AR) is a reliable, noninvasive method of measuring the dimensions of the nasal airway. METHODS: In 44 patients, we performed acoustic rhinometric measurements of nasal airway cross-sectional area, followed by hospital-based polysomnography and nasal continuous positive airway pressure (nCPAP) level titration. We compared anatomic nasal obstruction to perceived nasal obstruction, as well as respiratory distress index and nCPAP titration level, using the Pearson correlation and multiple linear regression analysis within body mass index groups. RESULTS: Perceived nasal obstruction correlated significantly with objective anatomic obstruction as measured by AR (r = 0.45, p < 0.01). For certain subgroup analyses in patients with a body mass index below 25, AR measurements correlated significantly with both nCPAP titration pressure (r = 0.85, p < 0.01) and respiratory distress index (r = 0.67, p = 0,03). CONCLUSION: Nasal airway function may be a significant component of SDB in some patients, perhaps playing a larger role in patients who are not overweight. The best responders to nasal surgery for SDB may be nonoverweight patients with nasal obstruction. AR along with nasal examination may be helpful in the evaluation and treatment of the SDB patient

OBJECTIVE: To assess behavior and quality of life in children with obstructive sleep apnea (OSA) undergoing tonsillectomy and adenoidectomy compared with control children. DESIGN: Prospective controlled study. SETTING: Hospital-based pediatric otolaryngology practice. PARTICIPANTS: Forty-two children (25 boys and 17 girls; mean [SD] age, 5.8 [2.5] years) with OSA confirmed by positive findings on polysomnography undergoing tonsillectomy and adenoidectomy and 41 control children (29 boys and 12 girls; mean [SD] age, 7.3 [3.8] years) with no history of snoring undergoing unrelated elective surgery. INTERVENTIONS: Parents completed the standardized Child Behavior Checklist and a validated pediatric OSA quality-of-life survey before and 3 months after surgery. MAIN OUTCOME MEASURES: Child Behavior Checklist T scores and score classifications and quality-of-life survey mean scores. RESULTS: Change in mean total problem T score was significantly greater in the OSA group (from 51.6 at baseline to 48.3 at follow-up) than in controls (from 45.5 at baseline to 46.7 at follow-up) (P = .03). The improvement in total T score classification (normal vs borderline or abnormal) was significant for children with OSA compared with control children (P = .009). Children with OSA had significant improvements in the quality-of-life survey mean total score and all individual domain scores compared with controls (P<.001). CONCLUSIONS: Behavioral and emotional difficulties are found in children with documented OSA compared with control children, and they improve after treatment. Large improvements in disease-specific quality of life are also found. Scores on a standardized measure of behavior assessment demonstrated significant correlation with scores on a validated quality-of-life instrument

Previous research has shown that increases in the rate of stimulation on a single electrode yield changes in pitch perception until the rate is increased beyond a given critical rate, after which changes in rate are only perceived as changes in loudness. The critical rate beyond which a rate increase no longer elicits a pitch change in most subjects is approximately 300 Hz, although a small number of subjects have been observed to have critical rates up to approximately 1000 Hz. In this article, we sought to determine if increasing the rate of stimulation beyond the critical rate (up to 12.8 kHz) would eventually result in new changes of perception (other than loudness.) Our data replicate the previously observed results that rates between approximately 300 and 1500 Hz are indistinguishable from each other. However, we observed the finding that a rate of stimulation well above the critical rate (starting between 1500 Hz and 12.8 kHz, depending on electrode and subject) can elicit changes in perception. The perceptual differences between these high rates were sometimes but not always labeled as pitch changes. This phenomenon needs further research to assess its potential relevance to speech perception using high rates of stimulation.

Cochlear implant electrode insertion is the most important step in cochlear implant surgery. Optimal placement facilitates optimal results. This article describes cochlear implant electrode insertion techniques in normal and abnormal cochleae and the currently available electrodes

Cochlear implants are electrical prostheses that partially replace the functions of the human ear. They bypass normal hearing operation to directly simulate the auditory nerve with electric current. The input acoustic signal passes through a filter bank and the output of each filter modulates the energy of a stimulation waveform delivered to a different intra-cochlear electrode. This approach attempts to mimic the signal processing that takes place in a normal ear. When fitting a cochlear implant to a patient who has lost his hearing after learning language, one important problem is how to optimize the frequency range of the filter bank This optimization seeks a tradeoff between maximum speech perception and the patient\\\\\\\'s subjective preference. Unfortunately, currently available tools to change the frequency-to-electrode mapping (i.e., the frequencies of the filter bank) are cumbersome to use. In a previous project we developed a real time speech processor for the Nucleus-22 and Nucleus-24 cochlear implants, based on a common PC and additional hardware drivers. The present project involves the development of a similar system that is adjustable in real time. In other words, the patient can modify the frequency-to-electrode map using computer keystrokes, and a visual representation of the frequency range employed by the filter bank is displayed on the monitor. The patient adjusts the frequency range interactively and selects the preferred setting in a much faster way than can be accomplished with commercially available hardware. If successful, this approach may be implemented in the next generation of hardware used to program cochlear implants in the clinic