Also known as trigonocephaly
The metopic suture is located at the front of the head and separates the frontal bones. It allows for transverse growth of the frontal bones and a widening of the anterior cranial fossa as the brain grows. This suture is the only one that naturally closes in childhood, between the ages of 0-2 years old. “Normal “closure of this suture typically results in the formation of a prominent midline ridge which is often felt along the middle of the forehead. “Premature” closure, however, causes more than a ridge. There is restriction of growth across the forehead leading to a triangular shape (trigonocephaly) and true narrowing of the orbits (hypotelorism). It is important to differentiate an isolated metopic ridge which does not require surgery, from true metopic synostosis, where surgery is recommended.
Surgical therapy for true metopic synostosis involves a fronto-orbital advancement which allows for widening the skull at the temporal fossa. This corrects the abnormal triangular shape of the forehead and increases the intracranial space in the anterior fossa. In addition, the surgery will also address the patient’s hypotelorism by placing bone grafts at the midline to widen the distance between upper part of the orbits.