Since your CT reports are suggestive of lateral semicircular canal dehiscence, likely cause for imbalance in your case is a condition known as lateral semicircular canal fistula. Usually it occurs as a complication of ear surgery or it may occur secondary to cholesteatoma. Only treatment which works is sealing the defect in the lateral semicircular canal by surgery
Next Steps
Consult nearby ENT specialist for confirmation of diagnosis and appropriate treatment if required