Magnetic resonance imaging in the pre-operative assessment of closed spinal dysraphism in children.

Magnetic resonance imaging (MRI) was used in the pre-operative assessment of closed spinal dysraphism in 61 paediatric patients. There were 25 cases of tethered cord, 6 of retethering at the site of myelomeningocele repair, 15 cases of diastematomyelia, 12 cases of lipomyelomeningocele, and 1 case each of dermal sinus, dermoid cyst and neurenteric cyst. MRI was found to have accurate correlation with surgical findings in all cases of tethered cord, and diastematomyelia. In cases of re-tethering at the site of previous myelomeningocele repair, while it was a significant advance on previous imaging techniques precise delineation of neural tissue and discrimination from post-operative fibrosis was frequently not possible. Imaging of dorsal lipomyelomeningoceles also correlated with surgical findings and provided accurate pre-operative information. However, the accuracy and pre-operative detail in cases of transitional and terminal lipomyelomeningoceles was disappointing.