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Updated: Jul 16, 2025

Author Spotlight: Development and Evaluation of a Standardized Rat Model for Calvarial Suture-Bony Composite Defects
Published on: May 10, 2024
Delayed Presentation of Sagittal Suture Craniosynostosis
Rishi N Modi1, Caitlyn C Belza1, George N Kamel
1From the UC San Diego School of Medicine.
Background:
Sagittal craniosynostosis typically presents as dolichocephaly or less frequently as clinocephaly, a "saddle-shaped" phenotype. This project aimed to characterize clinically relevant differences between sagittal synostosis phenotypes and examine the etiology of the delay in presentation.
Methods:
An institutional review board-approved retrospective review was performed from January 1999 to November 2018 at a single institution. Analyses examined correlations between subphenotype, time of presentation, minor suture fusion, developmental delay, and operative technique.
Results:
One hundred sixty patients diagnosed with single-suture sagittal craniosynostosis were identified. A total of 30.6% had a saddle phenotype (n = 49) and 69.4% had dolichocephaly (n = 111). Patients with the saddle phenotype were more likely to present with a developmental delay and to have at least 1 minor suture fused than patients with dolichocephaly were. Patients with the saddle phenotype presented for surgery at an older age and were more likely to undergo open cranial vault repair, with increased blood loss, higher transfusion volume, and longer time.
Conclusions:
This study highlights clinical differences in sagittal craniosynostosis phenotypes and shows that developmental delay is an initial presentation of the saddle phenotype. The saddle phenotype also correlated with fusion of the minor squamous and sphenoid sutures. The link between developmental delay and minor suture fusion was notable and should be explored with a larger sample size. Patients with saddle synostosis present for surgery at an older age than patients with dolichocephaly and therefore are more likely to receive open cranial vault repair, with a taxing intraoperative experience characterized by increased blood loss, increased transfusions, and longer operation time.
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