Superficial Siderosis: A Case Report of Underdiagnosed Disorder

Superficial siderosis (SS) is caused by subpial hemosiderin deposition due to chronic low-grade bleeding into the subarachnoid space. Dural tears are the most common etiology. Slowly progressive gait ataxia and hearing impairment are common clinical manifestations. Brain magnetic resonance imaging (MRI) shows linear superficial hypointensity on the T2 weighted images and gradient echo. The therapeutic approach is surgical repair of the bleeding source. The patient presented with progressive hearing loss and ataxia. Neurological examination revealed bilateral hearing loss, nystagmus, dysarthria, brisk deep tendon reflexes, and severe ataxia. Brain MRI showed linear superficial siderosis in the cerebrum, cerebellum, and brain stem. Spinal MRI showed ventral epidural cerebrospinal fluid (CSF) collection and disc-osteophyte complex. Six months after the surgical repair of the dural defect, the patient's neurological examination demonstrated improvement in ataxia and dysarthria. The patient was able to walk without any assistance. Surgical repair of the underlying bleeding source may be beneficial in preventing the progression and improving the symptoms of superficial siderosis SS. This case suggests that SS symptoms are potentially reversible by surgical treatment of the underlying spinal CSF leak after a long disease course.