Diastematomyelia: a 35-year experience.

STUDY DESIGN: Retrospective case series study. OBJECTIVE: This article describes our experience of the management of diastematomyelia. SUMMARY OF BACKGROUND DATA: Diastematomyelia is a rare entity, which presents distinct clinical characteristics and requires different managements compared with other more common occult spinal dysraphism. METHODS: A total of 156 patients with diastematomyelia were reviewed. All the patients underwent neurological and radiological examinations. Surgical excision of the lesion was performed for most patients and intradural exploration of the lumbar region was done to release tethering of conus in some patients. One patient died and autopsy was performed. Follow-up was carried out for all the patients, including surgical and nonsurgical approaches. RESULTS: There were 123 cases of type I diastematomyelia and 33 cases of type II diastematomyelia. The lumbar and thoracolumbar region was the most common site for diastematomyelia, and most spinal cords were split among 6 segments. The postoperative course was complicated by cerebrospinal fluid leakage in 2 patients, temporary neurological deterioration in 4 patients, and epidural hematoma in 1 patient. All cases did not have aggravation of symptoms during the follow-up of 2 to 20 years (mean of 4.5 yr). For the 123 patients with type I diastematomyelia, clinical symptoms were improved in 96 after surgical intervention and no worsening or occurrence of new clinical signs were observed during the follow-up. Those who did not receive surgery showed stabilization of neurological manifestation. Of the 33 type II cases, 9 surgical patients remained neurologically stable during the postoperative years without significant improvement in function, and 24 nonsurgical patients neither improved nor worsened in their neural deficit. CONCLUSION: Surgical treatment is the necessary management for type I diastematomyelia causing progressive neurological deterioration or with tethered filum, whereas conservative treatment is recommended to asymptomatic type I diastematomyelia and all type II diastematomyelia. LEVEL OF EVIDENCE: 5.