Abstract
Background: Superficial siderosis (SS) is a rare condition in which hemosiderin, an iron storage complex, is deposited in neural tissues because of recurrent subarachnoid bleeding. Hemosiderin deposition in the vestibulocochlear nerve (CN VIII), brain, spinal cord and peripheral nerve can cause sensorineural hearing loss (SNHL) and postural imbalance, but much remains unknown about the vestibular manifestations of SS.Objectives: To report the clinical course, cochleovestibular status, and patterns of vestibulopathy during follow-up of a relatively large case series, and to discuss the possible pathophysiological mechanism of vestibular deterioration.Methods: Six patients diagnosed with SS by magnetic resonance imaging (MRI) were enrolled. Their medical records and radiological findings were retrospectively reviewed, particularly in terms of progression of the vestibulocochlear manifestations and the radiological characteristics.Results: All six patients had SNHL. Five of them exhibited progressive hearing loss over years, which was asymmetric in four. On their most recent evaluations, patients showed cerebellar ataxia with combined central and peripheral vestibulopathy on both sides (n = 4), a bilateral peripheral vestibulopathy (n = 1) or isolated central vestibulopathy (n = 1). Notably, the former four patients showed an evolution of isolated central vestibulopathy into combined central and peripheral vestibulopathy. Hypo-intense lesions on T2 weighted MRIs were evident around the cerebellum in all patients, but such lesions were observed around the brainstem in five and the CN VIII in four. The cochlea-vestibular dysfunction generally progressed asymmetrically, but no left-right asymmetry was evident on MRI.Conclusions: SS typically presents as bilaterally asymmetric, progressive cochleovestibular dysfunction with cerebellar ataxia. The pattern of vestibular dysfunction is usually combined central and peripheral vestibulopathy on both sides. Thus, precise identification of audiovestibular dysfunction and central signs is essential in SS, and patients with SS should undergo regular, comprehensive neurotological evaluation to optimize their treatments and prognosis.
Highlights
Superficial siderosis (SS) is a rare condition in which hemosiderin, an iron-storage complex, is deposited in neural tissues because of recurrent subarachnoid bleeding [1]
A 78-year-old female patient presented with cerebellar ataxia without hearing loss 11 years prior to her initial neurotological evaluation
Symmetrical mild hearing loss in both ears was observed on Pure tone audiometry (PTA)
Summary
Superficial siderosis (SS) is a rare condition in which hemosiderin, an iron-storage complex, is deposited in neural tissues because of recurrent subarachnoid bleeding [1]. The symptoms can vary depending on the distribution of hemosiderin deposition; deposition in the cerebellum and vestibulocochlear nerve (CN VIII) can cause sensorineural hearing loss (SNHL) in addition to cerebellar ataxia and postural imbalance [3, 4]. Another study reported that only bilateral peripheral vestibulopathy is evident in SS patients [8]. Such inconsistent results suggest that misidentification of vestibular status in SS patients may pose diagnostic and therapeutic challenges, especially during rehabilitation therapy employing the vestibulo-ocular reflex (VOR) in which identification of the precise vestibular status is of critical importance [5, 9]. Hemosiderin deposition in the vestibulocochlear nerve (CN VIII), brain, spinal cord and peripheral nerve can cause sensorineural hearing loss (SNHL) and postural imbalance, but much remains unknown about the vestibular manifestations of SS
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
