Surgical treatment of late neurological deterioration in children with myelodysplasia.

Late deterioration of the neurological condition in patients operated on for myelomeningocele repair has been repeatedly reported in the literature. At the present time magnetic resonance imaging (MRI) allows one to recognize various pathological conditions which can be amenable to surgical correction in these patients, such as Chiari type II malformation, hydro/syringomyelia, decompensated hydrocephalus, and tethered spinal cord. The authors report their experience with 26 myelodysplastic children operated on for myelomeningocele repair in the early neonatal period, who exhibited late deterioration at variable time intervals from the first operation. The children were examined pre-operatively by means of MRI; the results were compared with those provided by MRI in 46 myelodysplastic children who underwent the investigation as a routine follow-up control. The MRI findings were subdivided into 4 main groups of increasing severity from 1 to 4; in some subjects, associated pathological conditions (Chiari II malformation, hydromyelia, etc.) were detected as well. Twenty-two out of the 26 patients with late neurological deterioration were operated on. Eleven of them (grades 2 to 4) underwent detethering of the fixed conus, with an improvement of their clinical picture from mild to good. On the other hand the remaining 11 subjects (grades 1 to 2) improved their condition following the correction of the associated abnormalities (malfunctioning CSF shunt: 5 cases; hydromyelia: 4 cases; symptomatic Chiari II malformation: 2 cases).