Cranial Distraction Osteogenesis Combined With Bone Thinning for Nonsynostotic Cranial Hyperostosis Following Ventriculoperitoneal Shunt.

Cranial distraction osteogenesis is widely used for craniosynostosis. However, it is rarely applied in nonsynostotic cranial deformities, such as cranial hyperostosis and asymmetry. The authors report the case of a 17-year-old patient with open-lip schizencephaly that developed cranial hyperostosis and skull asymmetry due to chronic over-drainage from a fixed-pressure ventriculoperitoneal shunt. He presented with neurological deficits and cranial deformation. The authors performed cranial distraction osteogenesis combined with bone thinning and conversion to a variable-pressure ventriculoperitoneal shunt. Preoperative planning with a 3D-printed model enabled controlled osteotomies and gradual cranial expansion. This approach resulted in successful cranial reshaping and neurological improvement. Cranial distraction osteogenesis is established for craniosynostosis, but its use in nonsynostotic deformities secondary to shunt over-drainage is reported here for the first time. This case highlights a novel application of cranial distraction osteogenesis in nonsynostotic cranial deformities related to shunt complications.