Dermoid tumors occurring at the site of previous myelomeningocele repair.

Four children with previously repaired myelomeningoceles presented toward the end of the first decade or early in the second decade of life with deteriorating lower-extremity and bladder function. Myelography and computerized tomography scanning demonstrated irregular filling defects at the area of the myelomeningocele repair, and surgical exploration disclosed dermoid tumors that were adherent to the placode and adjacent roots. Dermoid tumors should be considered in the differential diagnosis of neurological deterioration in children with a repaired myelomeningocele.