Cord Splitting Access to Ventral Intradural Cysts of Cervicothoracic Junction and Thoracic Spine

Abstract

Surgical treatment of ventrally located intradural cysts is difficult and controversial. Laminectomy with division of the denticulate ligaments and gentle cord mobilization remains the standard approach but risks further neurologic deterioration secondary to cord manipulation. Our purpose is to evaluate the safety and effectiveness of a midline cord-splitting approach as an alternative for treating ventral thoracic intradural cysts. We describe 2 patients who were treated for ventral intradural cysts causing progressive and severe myelopathy. Under general anesthesia and continuous neurophysiologic monitoring, laminectomy, durotomy, and cord splitting through a midline approach gave direct access to both lesions. Cyst drainage was supplemented by a cystopleural shunt in 1 case. Cyst collapse and cord reexpansion were documented in both patients with a magnetic resonance imaging scan 1 week after surgery. In both cases there was a significant neurologic improvement, which was maintained 2 years postoperatively. Intraoperative monitoring recorded no loss of somatosensory or motor potentials during surgery. Follow-up magnetic resonance imaging scans 2 years postoperatively showed no evidence of cyst recurrence, and both patients remained neurologically improved and stable. We have been able to drain 2 ventral intradural cysts using a cord-splitting technique. This has allowed safe access to purely ventrally located lesions, which were inaccessible dorsally or dorsolaterally. By using this method we have been able to avoid a more invasive ventral transthoracic approach necessitating vertebrectomy and reconstruction and risking serious complications.