Facial Nerve Function and Hearing Following Facial Nerve Decompression for Traumatic Facial Nerve Palsy Through Posterior Tympanotomy Approach: A Descriptive Study.

To assess Facial Nerve function and hearing status among patients who have undergone facial nerve decompression via the Posterior tympanotomy approach for traumatic facial nerve palsy. A descriptive study was carried out in a tertiary referral centre. Patients with traumatic facial nerve palsy (HB VI) who underwent facial nerve decompression via posterior tympanotomy approach were enrolled in the study after at least 3 months of the surgery. Their facial nerve function was graded using the House Brackmann (HB) score, and their hearing threshold was analysed using pure tone audiometry. 18 patients were enrolled in the study. Immediate onset facial palsy was seen in 14 (77.7%) patients, while 4 (22%) had delayed onset. The mean time between the trauma and surgery was 18.8 ± 20.3 days. Out of 11 patients operated within 2 weeks of trauma, 5 patients (45%) had perfect recovery (HB I), while all patients had good recovery (HB I or II). 6 patients were operated between 2 weeks and 2 months of trauma, out of which 2(33%) had perfect recovery, 5(83%) had good recovery while 1 (16%) had poor recovery (HB III). Only one patient was operated on beyond 2 months of the traumatic event and had a poor recovery. Spearman's correlation between the time gap between trauma and surgery and post-operative facial nerve function was statistically significant ( = 0.024). The mean air conduction threshold measured using pure tone audiogram in the pre-operative and post-operative period was 27.94 ± 13.63 and 23.56 ± 11.88, respectively. Wilcoxon signed ranks test demonstrated statistically no significant change in preoperative and post-operative air conduction, bone conduction, and air-bone gap (p = 0.068, 0.231, 0.107 respectively). Posterior tympanotomy is an excellent approach for facial nerve decompression. Facial nerve decompression done within 2 weeks of trauma had better recovery than those done later. Facial nerve decompression via posterior tympanotomy approach preserves the hearing of the patients.