Idiopathic thoracolumbar spinal epidural arachnoid cysts: A case report and systematic review

Idiopathic spinal epidural arachnoid cysts (SEACs) are rare and may cause myelopathy and cord compression. They typically arise from a congenital defect in the dura that communicates with the intrathecal subarachnoid space. Although the ideal treatment of SEACs is direct dural repair and cyst excision, there is as yet no clear standard of care for the management of these lesions. A 47-year-old female presented with myelopathy attributed to an magnetic resonance imaging-documented posterior epidural T12-L2 cyst (i.e., 1.1 × 6 × 3.3 cm) lesion. The patient underwent a direct dural repair of the fistulous communication between the subarachnoid space and the cyst, along with cyst drainage/ excision through a right-sided laminotomy. Postoperatively, the patient was asymptomatic. We additionally reviewed the literature regarding the management of SEACs. Our review yielded 14 articles involving 18 patients with predominantly thoracolumbar (57%) SEACs that were either communicating (61%) or not communicating (39%) with the subarachnoid space. They averaged 35.5 years of age and exhibited a male preponderance (66%). Symptoms typically included pain (78%), followed by weakness/myelopathy (42%). Surgery frequently included bilateral laminectomies (57%) followed by unilateral laminectomies (50%) that typically resulted in symptom resolution. SEACs are rare typically thoracolumbar lesions that may cause myelopathy which resolves following direct dural closure/subarachnoid fistulous occlusion.