Bryan K. Ward

Hearing outcomes after surgical plugging of the superior semicircular canal by a middle cranial fossa approach

Objective To determine postoperative hearing outcomes after surgical plugging via middle cranial fossa approach for superior semicircular canal dehiscence syndrome (SCDS). Study Design Clinical review. Setting Tertiary care medical center. Patients Forty-three cases of SCDS based on history, physical examination, vestibular function testing, and computed tomography imaging confirming the presence of a dehiscence. All patients underwent surgical plugging of the superior semicircular canal via middle cranial fossa approach. Intervention Pure tone audiometry was performed preoperatively and at 7 days and at least 1 month postoperatively. Main Outcome Measures Change in air-bone gap (ABG) and pure tone average (PTA). Results Preoperative average ABG across 0.25, 0.5, 1, and 2 kHz was 16.0 dB (standard deviation [SD], 7.5 dB). At 7 days postoperatively, average ABG was 16.5 dB (SD, 11.1; p = 0.42), and at greater than 1 month was 8.1 dB (SD, 8.4; p < 0.001). 53% (95% confidence interval, 33–69) of affected ears had greater than 10 dB increase in their 4-frequency (0.5, 1, 2, and 4 kHz) PTA measured by bone-conduction (BC) threshold 7 days postoperatively and 25% (95% confidence interval, 8–39) at greater than 1 month postoperatively. Mean BC PTA of affected ears was 8.4 dB hearing loss (HL) (SD, 10.4) preoperatively. Compared with baseline, this declined to 19.2 dB HL (SD, 12.6; p < 0.001) at 7 days postoperatively and 16.4 dB HL (SD, 18.8; p = 0.01) at greater than 1 month. No significant differences in speech discrimination score were noted (F = 0.17). Conclusion Low-frequency air-bone gap decreases after surgical plugging and seems to be due to both increased BC thresholds and decreased AC thresholds. Surgical plugging via a middle cranial fossa approach in SCDS is associated with mild high-frequency sensorineural hearing loss that persists in 25% but no change in speech discrimination.

Near-dehiscence: clinical findings in patients with thin bone over the superior semicircular canal.

Objective To determine whether patients with thin bone over the superior semicircular canal can develop signs or symptoms of superior canal dehiscence syndrome (SCDS). Study Design Retrospective case series. Setting Tertiary referral center. Patients All patients from our institution found to have thin but not frankly dehiscent bone over the superior canal despite symptoms and signs of SCDS. Main Outcome Measures Preoperative CT imaging, symptoms, audiometry, vestibular evoked myogenic potentials (VEMP), and intraoperative electrocochleography (ECochG) results were reviewed. Symptoms were assessed at least 1 month postoperatively in all patients, and postoperative physiologic data are presented when available. Results Ten patients (11 ears) had thin bone over the superior semicircular canal at surgery. All presented with autophony or sound- and/or pressure-induced vertigo, in addition to at least 1 physiologic measure consistent with SCDS. CT imaging was read as showing either dehiscence (36%) or marked thinning of bone overlying the affected canal (64%). Preoperative median low-frequency air-bone gap (ABG) was elevated (10.9 dB; interquartile range [IQR], 8.8–12.5), with 4 patients demonstrating negative bone conduction thresholds. Patients had elevated oVEMP amplitude (median, 20.7; IQR, 6.7–22.1) &mgr;V and ECochG SP/AP ratios (median, 0.59; IQR, 0.54–0.67). Postoperative ABG and SP/AP ratio decreased significantly compared with preoperative values (p < 0.05), and all patients reported symptomatic improvement. Conclusion Symptoms typical of SCDS can occur in cases with thin but not dehiscent bone. Surgical plugging or resurfacing can reduce symptoms in such cases.

Bilateral Vestibular Deficiency: Quality of Life and Economic Implications

IMPORTANCE Bilateral vestibular deficiency (BVD) causes chronic imbalance and unsteady vision and greatly increases the risk of falls; however, its effects on quality of life and economic impact are not well defined. OBJECTIVE To quantify disease-specific and health-related quality of life, health care utilization, and economic impact on individuals with BVD in comparison with those with unilateral vestibular deficiency (UVD). DESIGN, SETTING, AND PARTICIPANTS Cross-sectional survey study of patients with BVD or UVD and healthy controls at an academic medical center. Vestibular dysfunction was diagnosed by means of caloric nystagmography. INTERVENTIONS Survey questionnaire. MAIN OUTCOMES AND MEASURES Health status was measured using the Dizziness Handicap Index (DHI) and Health Utility Index Mark 3 (HUI3). Economic burden was estimated using participant responses to questions on disease-specific health care utilization and lost productivity. RESULTS Fifteen patients with BVD, 22 with UVD, and 23 healthy controls participated. In comparison with patients with UVD and controls, patients with BVD had significantly worse DHI (P < .001) and HUI3 scores. Statistically significant between-group differences were observed for overall HUI3 score (P < .001) and for specific attributes including vision, hearing, ambulation, emotion, and pain (P < .001 for all). Generalized linear model analysis of clinical variables associated with HUI3 scores after adjustment for other variables (including sex, race, education, age, and frequency of dizziness-related outpatient clinic visits) showed that the presence of UVD (P < .001) or BVD (P < .001), increased dizziness-related emergency room visits (P = .002), and increased dizziness-related missed work days (P < .001) were independently associated with worse HUI3 scores. Patients with BVD and UVD incurred estimated mean (range) annual economic burdens of

Vestibular dysfunction: prevalence, impact and need for targeted treatment.

13,019 (

Characterization of Vestibulopathy in Individuals with Type 2 Diabetes Mellitus

0-

Magnetic Vestibular Stimulation in Subjects with Unilateral Labyrinthine Disorders

48,830) and

Superior Canal Dehiscence Syndrome: Lessons from the First 20 Years

3531 (

Basal cell adenocarcinoma of a hard palate minor salivary gland: case report and review of the literature

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Physical Performance and a Test of Gaze Stabilization in Older Adults

48,442) per patient, respectively. CONCLUSIONS AND RELEVANCE Bilateral vestibular deficiency significantly decreases quality of life and imposes substantial economic burdens on individuals and society. These results underscore the limits of adaptation and compensation in BVD. Furthermore, they quantify the potential benefits of prosthetic restoration of vestibular function both to these individuals and to society.

The reliability, stability, and concurrent validity of a test of gaze stabilization

This manuscript is the first in a series on vestibular neuropharmacology, and serves to establish why it is important to develop pharmacologic interventions to treat disorders of the vestibular system. We will review the prevalence of vestibular disorders, present studies that describe the impact of vestibular disorders on quality of life and clinically significant outcomes such as falls, and discuss the need for rational, targeted treatment. We will advance a central hypothesis, that for vestibular disorders with a well-defined pathophysiology, targeted, effective treatments exist.