Concurrent split cord malformation and teratoma: dysembryology, presentation, and treatment.

Split cord malformation (SCM) is a rare form of spinal dysraphism in which the spinal cord is divided in the sagittal plane, forming a double neural tube. In addition to being associated with a variety of malformations, SCM may occur with spinal cord tumors, with only exceptional cases involving teratomas. As only eight patients with a teratoma associated with SCM have been reported, their presentation characteristics and treatment are currently unclear. We review the literature of all patients with SCM with concurrent spinal teratoma, discuss the potential dysembryology, and report the first case of SCM with concurrent spinal teratoma in an elderly patient. The mean age of those with concurrent SCM and teratomas was 39.4 years, with 55.6% occurring in females. The lumbar spine was the most frequent location for teratomas (66.7%), with the Type II malformation more commonly occurring with these tumors (75%). The duration of symptoms varied widely, ranging from 1 month to 5 years, with the average duration being nearly 2 years. Back pain (87.5%) and lower extremity weakness (75%) were the most common presenting symptoms. As SCM may be associated with progressive neurological deterioration and teratomas can contain immature or malignant components, surgery should be attempted with the goal of gross total resection. Nonetheless, in patients with a concurrent tumor and spinal dysraphism, spinal teratomas should be considered in the differential diagnosis. Gross total resection of these lesions may be safely achieved even in the presence of SCM using intraoperative electrophysiologic monitoring.