Two Year Comparison of Sagittal Synostosis Morphometric Outcomes Following Open Posterior Expansion Versus Endoscopic Strip Craniectomy with Helmet Molding Performed before Four Months of Age.

BACKGROUND: Open middle and posterior cranial vault expansion (OPVE) or endoscopic (ES) strip craniectomy are two surgical techniques for normalization of head shape in isolated sagittal synostosis. This study aims to compare two-year cranial morphometrics after these two approaches.

METHODS: We performed morphometric analysis on preoperative (t0), immediately post-operative (t1) and 2-year (t2) postoperative CT scans of patients who underwent OPVE or ES prior to 4 months of age. Perioperative data and morphometrics were compared between the two groups and age-matched controls.

RESULTS: Nineteen patients were included in the ES cohort, 19 age-matched patients in the OPVE cohort, and 57 as controls. Median surgery time and blood transfusion volume were less for the ES approach (118 min; 0cc) compared to OPVE (204 min; 250cc). Anthropometric measurements after OPVE were closer normal controls at t1 compared to ES, but the skull shapes were comparable at t2. In the mid-sagittal plane, anterior vault was higher after OPVE at t2 compared to both ES and controls, but the posterior length was shorter and closer to controls than the ES cohort. Cranial volumes were like controls for both cohorts at t2. There was no difference in complication rate.

CONCLUSIONS: Both OPVE and ES techniques result in normalization of cranial shape in patients with isolated sagittal synostosis after two years with minimal morphometric differences. Family decision-making between the two approaches should be based on age at presentation, avoidance of blood transfusion, scar pattern, and availability of helmet molding and not on expected outcome.

LEVEL OF EVIDENCE: III.