A Novel Noninvasive Screening Method for Early Detection of Sagittal Craniosynostosis Using the Surface Cranial Index.

Objective: This study aimed to evaluate the diagnostic value of a novel anthropometric parameter, the surface cephalic index (SCI), in the early screening of sagittal craniosynostosis (SC), and to compare its diagnostic performance with that of the traditional cephalic index (CI).

Methods: A retrospective case-control study was conducted, involving 54 children diagnosed with SC from June 2015 to September 2022 across three hospitals. A control group of 1350 age-matched children without cranial deformities was selected. SCI and CI were calculated using preoperative CT data and 3-dimensional cranial models reconstructed with Materialise Mimics 26.0 software. Diagnostic performance was assessed using Spearman correlation, logistic regression, receiver operating characteristic (ROC) curves, and McNemar test.

Results: Surface cephalic index was significantly negatively correlated with SC (ρ= -0.301, P<0.001). The SCI-based logistic model yielded an AUC of 0.951 (95% CI: 0.922-0.980), with 68.52% sensitivity and 97.63% specificity. Diagnostic accuracy was statistically comparable between SCI and CI (P=0.47). A cutoff value of 77.36% for SCI was established for screening purposes.

Conclusion: Surface cephalic index is a newly developed, noninvasive, and radiation-free cranial measurement index that relies solely on external anatomic landmarks. Compared with CI, it eliminates the need for CT imaging, reducing risk and cost while maintaining high diagnostic performance. Its simplicity, accessibility, and safety make SCI a practical tool for early SC screening, particularly in pediatric, primary care, and home settings. It addresses key limitations of CI and holds strong potential for broader clinical application.