Influence of Bone Defects After Endoscope-Assisted Suturectomy on Monobloc Advancement in Syndromic Bilateral Coronal Craniosynostosis Patients

Surgery is performed for craniosynostosis to enlarge intracranial volume and improve cranial morphology. Endoscope-assisted suturectomy is one of the effective treatments. Compared with other techniques, it is reported to be low invasive and enables improvement of cranial volume and morphology at an early age. At the National Center for Child Health and Development (Tokyo, Japan), endoscope-assisted suturectomy is performed for all patients with craniosynostosis under the age of 3 months. Bone defects are sometimes observed several years after endoscope-assisted suturectomy. In syndromic bilateral coronal craniosynostosis patients in whom fused coronal sutures are removed, bone defects often remain in the temporal region. These may cause difficulty in setting the osteotomy line and placing distraction device for later monobloc advancement. In the present study, syndromic bilateral coronal craniosynostosis patients who underwent endoscope-assisted suturectomy between 2017 and 2022 at our hospital were retrospectively reviewed to investigate residual bone defects after the operation. As monobloc advancement, tongue-in-groove technique and placing internal distractors were assumed, and cranial bone defects between the ages of 3 and 5 years were evaluated in 3D by using image processing software. Five patients were included, and in 2 patients, the bone defects in the temporal regions were deemed large enough to interfere with making the bandeau or restrict the use of internal distractors for monobloc advancement. When performing suturectomy for syndromic craniosynostosis patients with midfacial concavity, careful surgical strategies that take into account future monobloc advancement should be considered.