Superficial siderosis of the central nervous system associated with ventral dural defects: bleeding from the epidural venous plexus

• Published in: Journal of neurology 2021-04, Vol.268 (4), p.1491-1494
• Main Authors: Takai, Keisuke, Taniguchi, Makoto
• Format: Article
• Language: English
• Subjects: Bleeding; Central nervous system; Cerebellar ataxia; Cerebellum; Cerebrospinal fluid; Computed tomography; Epidural; Hemorrhage; Magnetic resonance imaging; Medical treatment; Medicine; Medicine & Public Health; Nervous system; Neurological diseases; Neurology; Neuroradiology; Neurosciences; Neurosurgery; Original Communication; Siderosis; Subarachnoid hemorrhage; Surgery; Thorax; Vertebrae
• ISSN: 0340-5354; 1432-1459
• DOI: 10.1007/s00415-020-10319-2

Objective Superficial siderosis of the central nervous system is a rare intractable disease induced by chronic subarachnoid hemorrhage. Neurological deficits, such as cerebellar ataxia and hearing difficulties, gradually progress if left undiagnosed. Hemosiderin deposition is irreversible because standard medical treatment has not yet been established. Interventions at the source of bleeding may be the key to a preferable outcome of treatment for chronic subarachnoid hemorrhage; however, the source is not clear in many cases. Methods Among the consecutive cases diagnosed with a spontaneous cerebrospinal fluid (CSF) leak, cases of superficial siderosis associated with a CSF leak due to a ventral dural defect were retrospectively analyzed. Results Among 77 cases of a CSF leak, 7 cases (9%) of superficial siderosis were identified (median age of 59 years, male, 4 cases). Defects were diagnosed on 1-mm sliced fast imaging employing steady-state acquisition MRI ( n  = 5), conventional myelographic CT ( n  = 1), or dynamic myelographic CT ( n  = 1) at high thoracic levels (T1–T4). All defects were repaired by direct neurosurgery. During surgery, continuous bleeding from the epidural veins of the internal vertebral venous plexus was identified as the source of subarachnoid hemorrhage. Epidural CSF pulsations through the defect prevented clot formation by the epidural veins. Dural repair stopped free communication between the subarachnoid and epidural spaces, leading to the disappearance of chronic subarachnoid hemorrhage. Conclusion Bleeding from the epidural venous plexus may be the cause of superficial siderosis associated with ventral dural defects. Neurosurgical repair may stop the progression of this condition.