Scaphocephaly: Part I: indices for scaphocephalic frontal and occipital morphology evaluation: long-term results

Abstract

Scaphocephaly is the most frequent craniosynostosis. Many correction techniques have been proposed. Their relevance is not completely appreciated by means of the Cranial Index, which cannot differentiate specifically the anterior and posterior modifications.The aim of this study was to propose a new fronto-occipital morphologic evaluation technique and its validation in normal and scaphocephalic patients, operated or nonoperated.

Patients and methods: Two evaluation measures (indices) were developed for frontal and occipital deformities, traced over a standard skull radiograph. It was initially applied in 16 normal skull radiographs. Forty-two scaphocephalies were evaluated before and after linear perisutural craniectomy technique. Short- and long-term evaluations were performed in the 42 operated cases, with a follow-up period of 10 or more years.The created indices were named Frontal Sagittal Index (FSI) and Occipital Sagittal Index (OSI). They are proportional measures between 2 cranial lengths.

Results: A significant difference was found for the FSI and the OSI between scaphocephalies and normal skulls. A significant difference was also found between indices before and after surgery, whether it was short- or long-term follow-up. No significant differences were found between the indices for the short- and long-term follow-up.

Conclusions: The FSI and the OSI were more precise measuring methods than the Cranial Index for the scaphocephaly anterior posterior morphologic evaluation and follow-up. There was also a stability of the results in the long-term follow-up with the technique used. We recommend these indices for the presurgical and result evaluation rather than the Cephalic Index.