Trigonocephaly, also called metopic synostosis or metopic craniosynostosis, is a type of craniosynostosis. The term craniosynostosis refers to the premature fusion of bones in a baby’s skull.

At St. Louis Children’s Hospital, our experienced surgeons have successfully treated hundreds of children for all types of craniosynostosis.

What is Metopic Synostosis?

Metopic Craniosynostosis: A Guide for Parents and Caregivers
Download Metopic Craniosynostosis: A Guide for Parents and Caregivers

A baby’s skull is made up of several small bones separated by growth plates called sutures. One suture runs from the top of the skull, down the middle of the forehead and toward the nose. This suture is called the metopic (forehead) suture.  

The metopic suture is the first suture in an infant’s head to close (fuse) as it grows. When this suture fuses prematurely, it can impact the baby’s appearance and brain development.

Babies with metopic synostosis have a noticeable ridge running down their forehead, causing the forehead to form in a triangular shape.

Metopic synostosis varies from mild cases where treatment is not required to more serious cases where surgery is necessary. When a baby is diagnosed early, our highly skilled surgeons can use minimally invasive endoscopic surgery.

How is Metopic Synostosis Treated?

Your doctor will consult with you, then recommend whether your baby needs surgery and what the best type of surgery is for your child. Options may include:

  • Endoscopic craniosynostosis repairThis minimally invasive procedure uses a small scope and minimizes scarring. After endoscopic metopic synostosis repair, your child will need to wear a helmet for several months. Learn more about post-surgical helmeting.  View photo examples of our patients who have had this prodedure. 
  • Open craniosynostosis repair surgeryFor children who are not candidates for minimally invasive surgery, our expert surgeons use a traditional technique to achieve excellent results.  View photo examples of our patients who have had this procedure. 

What Causes Metopic Craniosynostosis?

While researchers are studying the potential connections between metopic craniosynostosis, genetic mutations and the positioning of a baby’s head in the pelvis, the exact cause of the condition remains unknown for now. 

How is Metopic Synostosis Diagnosed?

Often, our doctors can diagnose metopic synostosis with a physical exam. They will also order a quick, painless imaging scan (X-ray or CT) to look at the bones and see if the sutures have fused prematurely. Your baby will not undergo any invasive medical testing.

We know you don’t want to be kept waiting to learn if your newborn has a skull abnormality. That’s why we give you the results and a clear treatment plan the same day, during your initial appointment.

Publications From Our Craniosynostosis Team Related to Metopic Synostosis

Contact Us

If you have concerns about the development of your baby’s head, please call us at 314.454.5437 or toll-free at 800.678.5437. We will gladly evaluate your child.