Audiologic Improvement Following MCF Approach for Spontaneous Cerebrospinal Fluid Leaks

Abstract

Objective: To determine the audiologic improvement after middle cranial fossa (MCF) approach to repair spontaneous cerebrospinal fluid (sCSF) leaks. Study Design: Retrospective cohort study. Setting: Tertiary referral center. Patients: Twenty-four consecutive patients (27 ears) with temporal bone sCSF leak over a 4-year period. Patient age, sex, ethnicity, body mass index (BMI), location of CSF leak, recurrence of CSF leak, and presence of encephalocele(s) were recorded. Intervention: Audiometric testing in patients undergoing MCF repair of temporal bone sCSF leak. Main Outcome Measures: Comparison of preoperative and postoperative pure-tone average (PTA), air-bone gap (ABG), and word recognition score (WRS) in the sCSF leak ear. Results: Out of 27 ears, 55% had multiple tegmen defects and 82% had more than or equal to 1 encephaloceles. There were no recurrent CSF leaks at a median follow up of 4 months. The mean (SD) preoperative PTA and ABG were 40.58 [15.67] and 16.44 [6.93] dB, respectively. There was significant improvement in mean PTA (10.28 [8.01] dB; p < 0.001; Cohen d = 0.95) and ABG (9.31 [7.16] dB; p < 0.001; Cohen d = 0.88) after sCSF repair. Mean WRS improved (by 3.07 [6.11] %; p = 0.024; Cohen d = 0.46) from a mean preoperative WRS of 93.16 [9.34]% to a mean postoperative WRS of 96.26 [6.49]%. Conclusions: MCF approach for repair of sCSF leaks yields significant improvement in conductive hearing loss and is highly effective in management of the entire lateral skull base where multiple bony defects are often identified.