Bilateral Vestibulopathy in Superficial Siderosis

Area of Science:

• Neurology
• Otolaryngology
• Radiology

Background:

• Superficial siderosis (SS) is a rare neurological disorder characterized by hemosiderin deposition in neural tissues due to recurrent subarachnoid bleeding.
• This iron deposition can affect the vestibulocochlear nerve (CN VIII), brain, spinal cord, and peripheral nerves, leading to sensorineural hearing loss (SNHL) and postural imbalance.
• The precise vestibular manifestations and their progression in SS remain incompletely understood.

Purpose of the Study:

• To detail the clinical course and cochleovestibular status of patients with superficial siderosis.
• To analyze patterns of vestibulopathy progression over time in a case series.
• To explore potential pathophysiological mechanisms underlying vestibular deterioration in SS.

Main Methods:

• Retrospective review of medical records and MRI findings in six diagnosed SS patients.
• Detailed assessment of vestibulocochlear manifestations and their radiological characteristics.
• Longitudinal evaluation of clinical course and neurotological status.

Main Results:

• All six patients presented with sensorineural hearing loss (SNHL), with five experiencing progressive, often asymmetric, hearing loss.
• Vestibular assessment revealed combined central and peripheral vestibulopathy in four patients, bilateral peripheral vestibulopathy in one, and isolated central vestibulopathy in one.
• MRI showed hypo-intense lesions around the cerebellum in all patients, brainstem in five, and CN VIII in four, correlating with progressive, asymmetric cochleovestibular dysfunction.

Conclusions:

• Superficial siderosis typically manifests as progressive, bilaterally asymmetric cochleovestibular dysfunction accompanied by cerebellar ataxia.
• The predominant pattern of vestibular dysfunction involves a combination of central and peripheral deficits.
• Comprehensive and regular neurotological evaluations are essential for accurate diagnosis and management of SS patients to optimize treatment and prognosis.