Cranial vault expansion in the management of postshunt craniosynostosis and slit ventricle syndrome

Background: Slit ventricle syndrome and postshunt craniosynostosis are uncommon complications after shunting procedures for congenital hydrocephalus. Slit ventricle syndrome occurs as a complication in 1 to 5 percent of patients after shunting procedures for hydrocephalus during infancy. These patients usually have had a shunt in place for years, with overdrainage of cerebrospinal fluid resulting in very small ventricles. Excessive intracranial decompression may result in ventricular collapse with the formation of slit-like ventricles and cranial vault collapse with secondary craniosynostosis. Methods: A retrospective review of 12 patients who had undergone cranial vault expansion for management of postshunt craniosynostosis and slit ventricle syndrome refractory to other treatment modalities was performed. All patients had initially been shunted for congenital hydrocephalus and subsequently under-went a mean of 4.9 shunt revisions before cranial vault expansion. Results: All 12 patients demonstrated decreased ventricular volume, with noncompliant slit-like ventricles in nine of these patients. Five patients demonstrated pancraniosynostosis, three patients demonstrated multiple sutural fusion, and isolated sagittal synostosis occurred in two patients. Two patients appeared to have functional synostoses with narrowed, overlapping sutures that were not actually fused. Eleven patients underwent bilateral fronto-orbital advancement with frontotemporoparietal expansion; one patient underwent only posterior vault expansion. Seven of the 12 patients required a mean of 2.3 shunt revisions after cranial vault expansion; five patients did not require subsequent revisions. Improvement in cranial vault shape was achieved in all 12 patients, as was improvement of neurologic symptoms in nine of the 12 patients. Conclusions: Cranial vault expansion is a useful approach in the management of the restricted cranium associated with slit ventricle syndrome and postshunt craniosynostosis. This approach resulted in a decreased need for shunt revisions and improvement of neurologic symptoms and cranial vault shape.