Long-term Outcome of Terminal Myelocystocele Patients

Introduction: A terminal myelocystocele, a closed form of a neural tube defect (NTD), can present as a large, fully epithelialized, cystic lumbosacral mass containing fat, cerebrospinal fluid (CSF) and neural tissue. The spinal cord terminates at a neural placode wherein the central canal opens into a CSF-filled cavity that is distinct from fluid in the subarachnoid space surrounding the spinal cord. This form of NTD, in our experience, was only associated with major caudal cell mass abnormalities, as these patients often have maldevelopment of the lower spine, pelvis, genitalia, bowel, bladder, kidney and the abdominal wall. This study will describe the clinical manifestations, surgical management and long-term outcome of our terminal myelocystocele patients.

Methods: To characterize this rare entity, a 13-year retrospective review was undertaken at our institution.

Results: Nine patients with terminal myelocystoceles were identified. In all cases, there were multiple congenital defects including cloacal exstrophy, imperforate anus, omphalocele, pelvic deformity, equinovarus or renal abnormality. Only 1 out of 9 patients has required a shunt for hydrocephalus. The main goal of neurosurgical intervention was to reduce the size of the mass, which can slowly enlarge over time. The spinal cord was also untethered, although these patients have no chance of bowel or bladder control. With a mean follow-up of 63 months, all patients remained neurologically stable. Impairment of lower extremity function is usually severe. However, some patients were ambulatory with the aid of a walker or orthotic device. All patients required a prolonged hospital stay as well as multiple operations prior to initial discharge.

Conclusion: Experienced, multispecialty care is needed to optimize the long-term outcome of these complex patients.