Clinical and Radiological Findings and Treatment of 8 Cases of Superficial Siderosis at Our Hospital

<p>  Background : Superficial siderosis (SS) is an intractable disease characterized by hemosiderin deposition in the subpial layers of the brain, typically the brainstem, cerebellum, and spinal cord. Patients with SS usually exhibit slow cerebellar ataxia and sensorineural hearing disturbances. It was recently reported that spinal magnetic resonance imaging (MRI) revealed an epidural cerebrospinal fluid (CSF) leak with spinal dural defects in patients with SS. However, there is currently no effective treatment that can improve the symptoms of SS. These characteristic findings are sometimes observed in patients with spontaneous intracranial hypotension (SIH). </p><p>  Materials and Methods : We summarized the clinical and radiological findings of 8 SS patients over 7 years treated at our hospital since January 2014. We examined epidural CSF leakage and spinal dural defects using conventional MRI plus fluid-attenuated inversion recovery (FLAIR) and/or coherent oscillatory state acquisition for the manipulation of image contrast (COSMIC) sequencing, selective dynamic CT myelography (CTM), and/or spinal endoscopy. Each patient with SS provided informed consent prior to undergoing dural closure.</p><p>  Results : Most patients complained of hearing and/or gait disturbances, whereas none experienced bleeding in the central nervous system. Six patients reported chronic slight headaches. Three patients had a history of SIH, while all had longitudinal epidural fluid collection ventral to the spinal cord, mainly at the thoracic spine. We examined the dural defects and surgically closed them in all 6 patients with chronic headache. MRI with COSMIC sequencing detected dural defects in 4 cases. Selective dynamic CTM was used in all 6 cases. Spinal endoscopy was used in 2 cases. Six patients underwent dural closure using sutures or a muscle patch. Although the headaches reported improved after surgery, the chief complaints of hearing and gait disturbance did not improve.</p><p>  Conclusion : The use of spinal MRI should be considered in patients with SS to detect epidural CSF leaks with spinal dural defects. However, selective dynamic CTM may be also useful for detecting dural spinal defects. Dural closure may be effective for SS patients with chronic headache; however, their neurological deficits may not resolve. Early diagnosis and treatment may be important for preventing neurological deficits in SS.</p>