Interpretation of Normal and Abnormal Tympanogram Findings in Eustachian Tube Dysfunction.

OBJECTIVE: To characterize the relationship between objective tympanogram values and patient-reported symptoms and associations with common comorbid conditions. STUDY DESIGN: Cross-sectional study with prospective data collection. SETTING: Tertiary medical center. METHODS: Patients undergoing routine audiometric evaluation between October 2018 and June 2019 were included. Participants with temporomandibular joint dysfunction, inner ear hydrops, and similar conditions were excluded. Symptoms were assessed with the 7-item Eustachian Tube Dysfunction Questionnaire. Demographics and medical comorbidities were recorded from the medical record. Analysis of tympanometric peak pressure (TPP), demographics, and comorbidities was performed to determine associations with clinically significant eustachian tube dysfunction (ETD) symptoms. RESULTS: A total of 250 patients were included with similar demographics: 101 (40.4%) in the asymptomatic group and 149 (59.6%) in the symptomatic group. The median (interquartile range) TPP was -10 (20) daPa and -25 (100) daPa in the asymptomatic and symptomatic groups, respectively. A diagnosis of rhinitis was more likely to be associated with significant ETD symptoms (adjusted odds ratio, 2.61; 95% CI, 1.23-5.63). A subgroup analysis revealed that symptomatic patients with normal TPP values were negatively skewed as compared with asymptomatic patients. This symptomatic group had a higher prevalence of rhinitis and chronic rhinosinusitis than the asymptomatic group. CONCLUSION: Patients with symptoms of ETD may have a TPP within a range typically considered normal per conventional standards. This suggests that the currently accepted interpretation of tympanometry findings may be insensitive for the diagnosis of less severe cases of ETD.

Endoscope-assisted middle fossa craniotomy for resection of inferior vestibular nerve schwannoma extending lateral to transverse crest.

OBJECTIVE The authors describe their results using an endoscope as an adjunct to microsurgical resection of inferior vestibular schwannomas (VSs) with extension into the fundus of the internal auditory canal below the transverse crest. METHODS All patients who had undergone middle fossa craniotomy for VSs performed by the senior author between September 2014 and August 2016 were prospectively enrolled in accordance with IRB policies, and the charts of patients undergoing surgery for inferior vestibular nerve tumors, as determined either on preoperative imaging or as intraoperative findings, were retrospectively reviewed. Age prior to surgery, side of surgery, tumor size, preoperative and postoperative pure-tone average, and speech discrimination scores were recorded. The presence of early and late facial paralysis, nerve of tumor origin, and extent of resection were also recorded. RESULTS Six patients (all women; age range 40-65 years, mean age 57 years) met these criteria during the study period. Five of the 6 patients underwent gross-total resection; 1 patient underwent a near-total resection because of a small amount of tumor that adhered to the facial nerve. Gross-total resection was facilitated using the operative endoscope in 2 patients (33%) who were found to have additional tumor visible only through the endoscope. All patients had a House-Brackmann facial nerve grade of II or better in the immediate postoperative period. Serviceable hearing (American Academy of Otolaryngology-Head and Neck Surgery class A or B) was preserved in 3 of the 6 patients. CONCLUSIONS Endoscope-assisted middle fossa craniotomy for resection of inferior vestibular nerve schwannomas with extension beyond the transverse crest is safe, and hearing preservation is feasible.

Anatomical Factors Influencing Selective Vestibular Neurectomy: A Comparison of Posterior Fossa Approaches.

Objectives To identify measurable anatomical factors that may guide the surgical approach for posterior fossa selective vestibular neurectomy (SVN) and predict identification of the vestibulocochlear cleavage (VCC) plane. Study Design Dissection of fixed cadaveric heads through retrolabyrinthine and retrosigmoid-internal auditory canal (RSG-IAC) approaches with measurement of landmarks. Setting Cadaveric dissection model. Main Outcome Measures Area of the Trautmann triangle (TT) and the distance from the posterior semicircular canal to the anterior border of the sigmoid along the posterior Donaldson line (pDL). VCC planes from each approach were calculated and compared. Results Overall mean pDL was 8.53 mm (range: 5-11.5 mm); mean TT area was 124 mm(2) (range: 95-237 mm(2)). The VCC was identified in 63% of ears through the retrolabyrinthine (RVN) approach alone, whereas 37% of ears required the RSG-IAC approach. In ears requiring IAC dissection, the VCC was found within 1 to 2 mm distal to the porus. The pDL (p < 0.05) and area of TT (p < 0.05) were significantly larger in the RVN group compared with the RSG-IAC group. Conclusion Ears amenable to the RVN approach had a greater pDL and TT area. These anatomical measurements may have a role in surgical planning and the choice of approach for SVN.