Faculty Bibliography

Amplitude modulations of pulsitile stimulation can be used to convey pitch information to cochlear implant users. One variable in designing cochlear implant speech processors is the choice of modulation waveform used to convey pitch information. Modulation frequency discrimination thresholds were measured for 100 Hz modulations with four waveforms (sine, sawtooth, a sharpened sawtooth, and square). Just-noticeable differences (JNDs) were similar for all but the square waveform, which often produced larger JNDs. The results suggest that a sine, sawtooth, and sharpened sawtooth waveforms are likely to provide similar pitch discrimination within a speech processing strategy.

The anterior condylar confluence (ACC) is located on the external orifice of the canal of the hypoglossal nerve and provides multiple connections with the dural venous sinuses of the posterior fossa, internal jugular vein, and the vertebral venous plexus. Dural arteriovenous fistulas (DAVFs) of the ACC and hypoglossal canal (anterior condylar vein) are extremely rare. The authors present a case involving an ACC DAVF and hypoglossal canal that mimicked a hypervascular jugular bulb tumor. This 53-year-old man presented with right hypoglossal nerve palsy. A right pulsatile tinnitus had resolved several months previously. Magnetic resonance imaging demonstrated an enhancing right-sided jugular foramen lesion involving the hypoglossal canal. Cerebral angiography revealed a hypervascular lesion at the jugular bulb, with early venous drainage into the extracranial vertebral venous plexus. This was thought to represent either a glomus jugulare tumor or a DAVF. The patient underwent preoperative transarterial embolization followed by surgical exploration via a far-lateral transcondylar approach. At surgery, a DAVF was identified draining into the ACC and hypoglossal canal. The fistula was surgically obliterated, and this was confirmed on postoperative angiography. The patient's hypoglossal nerve palsy resolved. Dural arteriovenous fistulas of the ACC and hypoglossal canal are rare lesions that can present with isolated hypoglossal nerve palsies. They should be included in the differential diagnosis of hypervascular jugular bulb lesions. The authors review the anatomy of the ACC and discuss the literature on DAVFs involving the hypoglossal canal.

Oral squamous cell carcinoma (SCC) has an unpredictable capacity to metastasize to the neck, an event that dramatically worsens prognosis. Metastasis occurs even in earlier stages when no neck lymph node involvement is clinically detectable (N0). Management of the N0 neck, namely when and how to electively treat, has been debated extensively. This article presents the controversies surrounding management of the N0 neck, and the benefits and pitfalls of different approaches used in evaluation and treatment. As current methods of assessing the risk for occult metastasis are insufficiently accurate and prone to underestimation of actual risk, and because selective neck dissection (SND) is an effective treatment and has minimal long-term detriment to quality of life, the authors believe that all patients who have oral SCC, excluding lip SCC, should be prescribed elective treatment of the neck lymphatics. However, this opinion remains controversial. Because of the morbidity of radiation therapy and because treatment of the primary tumor is surgical, elective neck dissection is the preferred treatment. In deciding the extent of the neck dissection, several retrospective studies and one randomized clinical trial have shown SND of levels I through III to be highly efficacious

OBJECTIVES: Since the advent of cochlear implants, age at implantation has declined as investigators report greater benefit the younger a child is implanted. Infants younger than 12 mos currently are excluded from Food and Drug Administration clinical trials, but have been implanted with Food and Drug Administration-approved devices. With a chance that an infant without profound hearing loss could be implanted because of the limitations of the diagnostic measures used with this population and the potential for additional anesthetic risks to infants younger than 1-yr-old, it is prudent to evaluate benefit in the youngest cochlear implant recipients. The goals of this research were to investigate whether significant gains are made by children implanted before 1-yr-old relative to those implanted at later ages, while controlling for potential covariates, and whether there is behavioral evidence for sensitive periods in spoken language development. It was expected that children implanted before age 1 yr would have more advanced spoken language skills than children implanted at later ages; there would be a negative relationship between age at implantation and rate of spoken language development, allowing for an examination of the effects of sensitive periods in spoken language development; and these trends would remain despite accounting for participant characteristics and experiences that might influence spoken language outcomes. DESIGN: Ninety-six children with congenital profound sensorineural hearing loss bilaterally and no additional identified disabilities who were implanted before the age of 4 yrs were stratified into four groups based on age at implantation. Children's spoken language development was followed for at least 2 yrs after device activation. Spoken language scores and rate of development were evaluated along with four covariates (unaided pure-tone average, communication mode, gender, and estimated family income) as a function of age at implantation. RESULTS: In general, the developmental trajectories of children implanted earlier were significantly better than those of children implanted later. However, the advantage of implanting children before 1-yr old versus waiting until the child was between 1 and 2 yrs was small and only was evident in receptive language development, not expressive language or word recognition development. Age at implantation did not significantly influence the rate of the word recognition development, but did influence the rate of both receptive and expressive language acquisition: children implanted earlier in life had faster rates of spoken language acquisition than children implanted later in life. CONCLUSIONS: Although in general earlier cochlear implantation led to better outcomes, there were few differences in outcome between the small sample of six children implanted before 12 mos of age and those implanted at 13 to 24 mos. Significant performance differences remained among the other age groups despite accounting for potential confounds. Further, oral language development progressed faster in children implanted earlier rather than later in of life (up to age 4 yrs), whereas the rate of open-set speech recognition development was similar. Together, the results suggest that there is a sensitive period for spoken language during the first 4 yrs of life, but not necessarily for word recognition development during the same period

BACKGROUND:Intraoperative surgical navigation has become widely accepted as an important tool for improvement of surgical outcomes and reduction of complication in endoscopic sinus surgery (ESS). The purpose of this study was to assess the clinical utility of intraoperative volume computed tomography (CT) scanning in endoscopic sinonasal and skull base procedures. METHODS:Retrospective review of patients who underwent intraoperative volume CT imaging (xCAT; XoranTechnologies, Ann Arbor, MI) during endoscopic sinonasal and skull base surgery during a 3-month period was performed. Intraoperative, computer-enabled triplanar review of reformatted 0.4-mm images was performed in all cases. RESULTS:Intraoperative volume CT scanning was completed in 25 patients. Surgical procedures included revision/primary ESS for chronic rhinosinusitis (CRS) with or without polyposis (12 cases) and mucoceles (6 cases) as well as endoscopic neoplasm resection (5 cases), endoscopic fibro-osseous lesion resection (1 case), and endoscopic meningoencephalocele repair (1 case). The indications for intraoperative CT scanning included assessment of surgical dissection (23 cases), extent of tumor resection (6 cases), and frontal stent placement (6 cases). Based on the intraoperative volume CT information, additional interventions, including additional tumor resection (2 cases), dissection of ethmoid partitions (2 cases), frontal bone drilling during Draf IIB (1 case), and repositioning of a frontal stent (1 case) were performed in 6 (24%) cases. CONCLUSION/CONCLUSIONS:Intraoperative volume CT scanning was successfully performed in 25 patients undergoing ESS. Because additional surgical intervention was performed in 24% of cases, this technology may have an important role in endoscopic sinonasal and skull base procedures.

OBJECTIVE: To determine the efficacy of pantoprazole therapy for daytime somnolence, psychomotor vigilance, and quality of life in patients with mild-moderate obstructive sleep disordered breathing (OSDB) and gastroesophageal reflux disease (GERD). STUDY DESIGN: Randomized, double-blind, placebo-controlled crossover trial. METHODS: Sixty patients with daytime sleepiness, mild-moderate OSDB and GERD were randomly assigned a 2-week treatment with pantoprazole 40 mg or placebo followed by a 2-week washout period and crossover respectively to 2-week treatment with placebo or pantoprazole. Outcomes included Epworth Sleepiness Score (ESS), sleep-related quality-of-life (FOSQ), and reaction time. RESULTS: With pantoprazole, patients reported statistically significantly greater improvement of overall reflux symptoms (P = 0.0003) and in ESS (P = 0.04). A significant improvement was noted in FOSQ for both treatments with a trend toward greater improvement with pantoprazole (P = 0.058). No improvement in reaction times was observed. CONCLUSION: Patients with coexistent GERD and OSDB noted significant improvement in daytime sleepiness after treatment with pantoprazole over placebo likely related to a reduction in nocturnal reflux-related arousals