Copyright @ 200 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited. 8 Unsuccessful Cochlear Implantation in Two Patients With Superficial Siderosis of the Central Nervous System *Verity H. Wood, *†Philip A. Bird, ‡Ellen C. Giles, and ‡William J. Baber *Department of Otolaryngology, Christchurch Hospital; ÞSouthern Cochlear Implant Programme, Christchurch; and þNorthern Cochlear Implant Programme, Auckland, New Zealand Objective: To highlight the potential adverse outcomes with cochlear implantation (CI) in patients with superficial siderosis. Patients: Two patients with superficial siderosis of the central nervous system with secondary sensorineural hearing loss. Intervention: Cochlear implantation. Main Outcome Measure: Postimplantation speech discrimina- tion scores. Results: In both cases, initial results after implantation were promising. However, in 1 case, their ability to use the CI rapidly declined after 1 week because of major difficulties adapting to electrical stimulation. For the other case, hearing rapidly declined over a 6-month period. Conclusion: The 2 patients reported did not benefit from CI in superficial siderosis that is in contrast to several previously published cases. Adequate counseling of patients with super- ficial siderosis is important when considering cochlear im- plantation as results are variable. Key Words: Cochlear implant VLeptomeningeal hemosiderosis VSensorineural hearing lossVSuperficial siderosis. Otol Neurotol 29:622Y625, 2008. Superficial siderosis (SS) (also known as leptomenin- geal hemosiderosis) is a rare progressive central nervous system disorder in which hemosiderin is deposited in the meninges surrounding the brain; this is secondary to recurrent subarachnoid bleeding of various etiology. Hemosiderin accumulates in the subglial tissues causing damage to the brain, spinal cord, and cranial nerves (1). Magnetic resonance imaging (MRI) has revolutionized the diagnosis of SS because, previously, it was a diag- nosis only confirmed at postmortem (2). Most patients (95%) experience progressive sensori- neural deafness that begins early in the disease (3,4). Other features include cerebellar ataxia (88%), pyramidal signs (76%), and dementia (24%). The age of onset, duration, and age at death is highly variable (4). Head trauma and prior intradural cerebral surgery are risk factors for developing SS (5). A cause for the chronic bleeding is only reported in approximately 50% of cases; therefore, treatment is difficult (4). In the idiopathic group, treatment is aimed at relieving symptoms and progression of disease. Cochlear implantation (CI) is a treatment for the sen- sorineural hearing loss (SNHL) caused by SS. Several studies published have reported benefit with CI in SS (6Y11). We report 2 patients with SS and profound SNHL who underwent CI. Initial good results were not maintained possibly because of the progressive neural deterioration associated with this condition. CASE REPORTS Case 1 A 53-year-old man presented with progressive SNHL over a 5-year period. This was associated with anosmia, incoordination, and unsteadiness with some falls prevent- ing him from cross-country running. He had initially been investigated with serial audiometry in a rural hospital. T2-weighted MRI scan showed very low signal around the basal cisterns, brainstem, and cerebellum, consistent with a diagnosis of moderate SS. The VIIth and VIIIth cranial nerves were normal, and magnetic resonance angiography demonstrated a small (G2 mm) sidewall aneurysm from the cavernous portion of the left internal carotid artery. No bleeding point was identified. Initially, hearing aids were used to help his hearing loss. When these were no longer effective (6 yr after Address correspondence and reprint requests to Philip Bird, Depart- ment of Otolaryngology, Christchurch Hospital, Christchurch, New Zealand; E-mail: verity.wood@gmail.com Otology & Neurotology 29:622Y625 Ó 2008, Otology & Neurotology, Inc. 622