Surgical Outcomes of Cranial Vault Expansion Following Treatment of Craniosynostosis in Complex Syndromes: A Retrospective-Prospective Patient Series

BACKGROUND: Posterior vault distraction osteogenesis (PVDO) is an alternative to fronto-orbital advancement for managing complex syndromic craniosynostosis. The authors evaluated clinical outcomes, cranial morphometric indices, and postoperative complications following PVDO. METHODS: This combined retrospective-prospective descriptive interventional case series included 16 patients with complex syndromic craniosynostosis who underwent PVDO. Two distraction devices were placed bilaterally on the posterior calvaria without dural detachment. Distraction was initiated on postoperative day 1 to 2, at a rate of 1 mm/day (0.5 mm twice daily). Devices were removed after 3 to 6 months. Cranial morphology was assessed using 3D-reconstructed CT processed with Mimics 23.0. RESULTS: Intracranial volume increased by 36.3% at device removal and 27.8% at 1-year follow-up. Posterior cranial fossa volume increased from 101.4±34.0 to 193.5±89.6 cm3 at device removal and to 196.5±45.6 cm3 at 1-year follow-up. The posterior cranial base area increased 2.2-fold, from 38.6±22.4 to 86.3±23.1 cm2 (P<0.001). Clinical signs of intracranial hypertension were present in 100% preoperatively and improved markedly postoperatively. Obstructive sleep apnea was diagnosed in 62.5% of cases. Minor complications occurred in 5 patients (31.25%): cerebrospinal fluid leak (12.5%), poor ossification (12.5%), and scalp thinning (6.25%). No infections or hardware exposure were observed. CONCLUSION: Posterior vault distraction osteogenesis is a safe and effective surgical approach for managing complex syndromic craniosynostosis. It significantly expands intracranial and posterior fossa volume while reducing symptoms of elevated intracranial pressure.