Clinicopathological Profile of Patients with Chronic Otitis Media Squamosal Disease with Labyrinthine Fistula from a Tertiary Care Centre in South India

Introduction: Labyrinthine fistula (LF) is a complication of chronic otitis media, especially in cases involving Squamosal disease. The primary objective in managing these cases is to safeguard both cochlear and vestibular functions while effectively addressing the disease. In this study, we provide compelling data from cases treated at our institution, highlighting their presenting symptoms, therapeutic strategies and outcomes. Methods: A retrospective review was performed of 20 patients with LF among 96 patients with chronic otitis media squamosal disease managed at our centre between 2018 and 2024 by two surgeons. The clinical features, management, and outcomes were analysed. Results: The incidence rate of LF was 20.8%. Although a positive fistula test was observed in only 15% of cases, preoperative imaging with computed tomography (CT) of the temporal bone was conducted in all 20 patients, suggesting a LF. Around nine patients (45%) had symptoms of vertigo preoperatively and all improved after surgery. There was an average increase of 5 dB, 8 dB and 2 dB improvement in hearing on comparing preoperative and postoperative pure tone average, air bone gap and bone conduction thresholds, respectively, in 15 patients who came for follow-up (average duration of three months follow-up). It was also found that those with a higher stage of fistula had poorer hearing outcomes. Conclusion: In our study, we observed a striking incidence of LF at 20.8%. Notably, the most frequently affected area was the dome of the lateral semicircular canal, underscoring the importance of careful evaluation in this region. The positive fistula sign and preoperative symptoms of giddiness are unreliable in the preoperative diagnosis of LF. The higher the stage of LF, the greater were the symptoms of giddiness, positive was the fistula sign, and the poorer was the hearing outcome.