Microsurgical Repair of Spontaneous Cerebrospinal Fluid Leaks

Introduction: Spontaneous intracranial hypotension (SIH) is an underdiagnosed, potentially disabling syndrome usually caused by spontaneous spinal cerebrospinal fluid (CSF) leaks. Cases refractory to conservative treatments can often be cured with microsurgical treatment. Few series have been published on surgical technique for treatment of this pathology.

Methods: All consecutive patients at a single institution who underwent microsurgical repair of their CSF leak were included. All patients were treated with a posterior approach and intraoperative monitoring. Ventral leaks were treated with laminectomy and spinal cord mobilization, removal of osteophyte, and combined intradural and extradural repair with extradural dural substitute onlay and primary intradural suturing of the leak. Leaks at the nerve root axilla were treated with laminectomy, partial facetectomy, and direct ligation. Patient data and demographics were collected from retrospective chart review. Intraoperative video and images were collected for three patients.

Results: Seven SIH patients with severe symptoms refractory to conservative treatments underwent surgery, all with leaks identified intraoperatively from C8 to T10. Five were longitudinal tears along the ventral dura from a small osteophyte, one was a meningeal diverticulum at the axilla of a nerve root extending ventrally, and one was a CSF-venous fistula at the axilla. Two of the six ventral leak patients had previously had anterior cervical surgery that failed to adequately treat the leak. One patient required re-operation for return of symptoms and a small leak at the site of dorsal durotomy was repaired. There were no post-operative infections or neurological deficits. Two patients had rebound headaches that resolved over time. All patients had resolution of symptoms and imaging at last follow up.

Conclusion : A posterior approach is safe and effective for the repair of CSF leaks causing refractory SIH. For ventral leaks, combined intradural and extradural repair may maximize durability of repair.