Introduction: Superior Semicircular Canal Dehiscence (SSCD) is an emerging neurosurgical subspecialty characterized by a myriad of audiological and vestibular symptoms, such as autophony, tinnitus, hearing loss, and dizziness [1-15]. Presentations are confirmed by high resolution computed tomography (CT) [1-15]. Surgical resolution has been varied for multiple symptoms, including hearing loss and dizziness [1,4-5,8-9,11]. Given the mixed results of symptom resolution of SSCD patients after surgical repair, we herein analyze the largest cohort of SSCD patients managed by a single neurosurgeon and ENT surgeon to date.
Methods: For this study, we identified 120 patients with 156 surgical repairs for SSCD. Gender, age, surgical side, history of ear trauma, and previous ear affliction were noted. Symptoms of autophony, amplification, aural fullness, tinnitus, hyperacusis, hearing loss, vertigo, dizziness, imbalance, oscillopsia, and headaches were recorded preoperatively and postoperatively. Fischer's Exact tests, Wilcoxon-Mann-Whitney tests, and multiple variable regression were performed using SAS version 9.4.
Results: Of 120 patients, the majority were female (n=76). Median age was 55 (± 12.7 years) and median follow up was 14 months (± 284.1). Previous ear affliction was present in 64 patients and previous trauma in 27 patients. Bilateral SSCD was present in 53 cases, with the right side (n=70) being the most repaired. Of the cohort, there were 5 surgical revisions and 11 incidents of CSF leak. There were no significant differences in gender, age, surgical side, history of ear trauma, previous ear affliction, time to follow-up, revision, or CSF leak. Preoperative symptoms were not significantly associated with any other variables. Increased postoperative dizziness and hearing loss was significantly correlated with females (p=.048, p=.041). Males significantly had better postoperative hearing (p=.044).
Conclusions: Resolution of SSCD symptoms after surgery may be dependent on gender; however, study limitations including sample size may affect our outcomes.
Patient Care: Understanding factors that contribute to the persistence of symptoms after surgery will help future patients with SSCD determine alternative avenues of care or, from a neurosurgical perspective, lead to improvements in operative technique.
Learning Objectives: By the conclusion of this session, participants should be able to
1) Understand the history and clinical diagnosis of SSCD
2) Learn of the minimally invasive technologies and materials used in the repair of SSCD.
3) Understand the common complications of surgery and factors influencing refractory symptoms.
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