A spinal extradural arachnoid cyst (SEAC) is a rare condition with unclear etiology. Herein, we report a series of symptomatic SEACs to illustrate features of SEACs in adults, surgical management, and outcomes.
A total of 34 consecutive patients who underwent microsurgical treatment were retrospectively reviewed. Patient characteristics were recorded in each case, including presenting symptoms, imaging findings, neurologic status, a surgical procedure performed and follow-up.
There were 19 (56%) male and 15 (44%) female patients, with the ages ranging from 16 to 71 years (average 45 years). The lesions were located in the cervical segment (n = 4, 12%), thoracic segment (n = 6, 18%), thoracolumbar segment (n = 10, 29%) and lumbar segment (n = 14, 41%). Clinical presentations included back pain (n = 18, 53%), sensory deficits (n = 14, 41%), weakness (n = 4, 12%) and gait ataxia (n = 4, 12%), with a mean duration of symptoms of 17 months. The lesion was hypointense with the spinal cord on T1-weighted images and hyperintense on T2-weighted images and showed no homogeneous enhancement after contrast medium injection. Communication between the cyst and subarachnoid space was found in 23 patients and the cyst was resected after fistula ligation. Postoperatively, patients were followed up for an average of 80 months. The patients’ symptoms dramatically improved and follow-up radiological images showed a complete disappearance of the cyst in all patients. No recurrence was observed in the dural repair group.
Patients with symptomatic SEAC present with obvious and persistent symptoms. Complete microsurgical cyst removal with the closure of the dural defect is the standard treatment procedure with good results and a low recurrence rate.

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