Incidence of persistent metopic suture in Australia: findings from 1034 three-dimensional computed tomography scans

To investigate the incidence of persistent, open metopic sutures in contemporary Australians aged 24 months and older.

Metopic suture evaluation was conducted on retrospective cranial/cervical computed tomography scans of patients aged 24 to 252 months who presented to the Women's and Children's Hospital in Adelaide, Australia, between 2010 and 2020. Suture ossification was graded according to Lottering scoring system based on 4 stages, on three-dimensional volume-rendered reconstructions (stage 1: fibrous tissue interface, stage 2: commenced fusion, stage 3: complete fusion and stage 4: obliterated suture). The complete persistent sutures were classified as stage 1. Partially closed sutures were classified into stages 2 and 3, while completely closed sutures were defined as stage 4.

One thousand thirty-four patients (61.2% male and 38.8% female) were included, with a mean age at scan of 66 months. More than half of patients were subject to scanning due to closed-head injuries. The incidence of persistent (completely open) metopic suture was 4.8% (2.3% in males and 2.5% in females). In comparison, a partially closed metopic suture was found in 6.3% of the study cohort, with the remaining sutures located along the metopic suture line, at the glabella, mid-part of the suture, bregma and glabella-bregma areas.

The prevalence of persistent metopic sutures in our study of the Australian population is 4.8%, and it is equally distributed between the genders. The pattern of suture closure can commence from any location along the suture line, which is in contrast to the existing literature.