A morphometric analysis of the cranial base in trigonocephaly.

Abstract

Trigonocephaly occurs when the metopic suture fuses prematurely. Few studies have documented the morphometry of the entire anterior cranium in trigonocephaly and not on the morphometric changes to the cranial fossae alone. Thus, this study aimed to determine and compare the dimensions of the anterior cranial fossa (ACF) in trigonocephaly and control groups. Additionally, volumetric assessments of the middle and posterior cranial fossae (MCF and PCF) were analysed to determine the amount of compensatory growth in these regions. Anatomical landmarks were used to measure the morphometry of the ACF, and volumes of the MCF and PCF on preoperative two-dimensional computed tomography scans of fifteen non-syndromic, isolated trigonocephaly patients between 2012 and 2023, and eight controls. Comparative assessment of the ACF revealed larger dimensions in younger more severe trigonocephaly patients when compared to the control cohort. Smaller ACF dimensions were recorded in older patients who presented with moderate and severe trigonocephaly compared to the control cohort. The volume of the MCF was found to be significant (p = 0.05), and the volume of the PCF was larger in trigonocephaly patients compared to controls. The PCF showed the largest incidence of compensatory growth (30.4%) in trigonocephaly patients. The frontal angle (FA) (p = 0.004) and endocranial bifrontal angle (EBA) were used to categorise the severity of trigonocephaly. The morphometric data obtained could assist craniofacial surgeons in understanding the changes that occur in the ACF to decide which type of corrective treatment is most suitable.