Assessment of Metabolic Markers and Osteoporosis in 250 SSCD Patients Treated With Middle Fossa Craniotomy.

BACKGROUND: Superior semicircular canal dehiscence (SSCD) is caused by bony defects in the arcuate eminence's osseous shell separating the labyrinth and the intracranial space. This pathological "third window" causes hydroacoustic transmission resulting in debilitating symptoms. Here, we examine the pathophysiological association between metabolic markers, previous medical history, and SSCD symptoms before and after middle fossa craniotomy treatment.

METHODS: This study was conducted between March 2011 and September 2020 with SSCD patients who underwent middle fossa craniotomy (MFC). We used Fisher's test to compare variables, including: bilateral SSCD, second surgery, ear anomaly, osteoporosis, arthritis, vitamin-D, and pre-/post-operative symptoms, and others. Point-biserial correlation analysis was performed to test correlations between continuous variables and categorical variables.

RESULTS: 250 SSCD patients underwent MFC repair. There was significant post-operative resolution in all symptoms (P < .0001). Lab 25-hydroxyvitamin D values correlated with pre-operative aural fullness (rpb = 0.29, P = .03), and pre-operative disequilibrium (rpb = -0.32, P = .02). Serum calcium values correlated with pre-operative hearing loss (rpb = 0.16, P = .02). Osteoporosis history (n=16, 6%) was more prevalent in female patients (P = .0001), associated with higher levels of pre-operative hearing loss (OR = 4.56, P = .02) and higher post-operative hearing loss resolution (OR=2.89, P=.0509).

CONCLUSION: Certain metabolic markers may predict SSCD presentation before and after surgery. Previous history of osteoporosis, autoimmune conditions, or arthritis may play a role in SSCD pathophysiology and can help predict clinical outcomes. Future evaluation should take metabolic lab values and acquire an exact medical history.