Metopic Synostosis (Trigonocephaly) | Symptoms & Causes

Before learning more about metopic synostosis, it’s helpful to understand the anatomy of a baby’s skull.


  • An infant’s skull has several plates of bone that are separated by fibrous joints, called sutures.
  • The sutures gradually close as the child grows and develops.
  • When the sutures close, the skull is fully formed as a solid piece of bone.

When a child has metopic synostosis:

  • The metopic suture­ — the joint that runs from the baby’s fontanel (the “soft spot” at the top of the head) down the forehead to the top of her nose­ — closes too early.
  • The baby develops a noticeable ridge extending along the center of her forehead.
  • Her forehead will look overly narrow.
  • Her eyes may be spaced too closely together.
  • The front of her skull may appear pointed and rather “triangular.”

Some children have very mild cases of metopic synostosis that do not require specific treatment. In more serious cases, however, the condition can cause:

  • developmental delays
  • learning and behavioral problems
  • vision problems

Surgery has proven to be a beneficial treatment for children whose metopic synostosis necessitates medical intervention.

What causes metopic synostosis?

In most children, metopic synostosis happens without any identifiable reason.

Sometimes, however, metopic synostosis occurs as a component of a rare genetic syndrome. The following disorders have been linked to metopic synostosis:

  • Baller-Gerold syndrome, which also causes abnormalities in the bones of the arms and hands
  • Jacobsen syndrome, which results from missing material within a certain chromosome
  • Muenke syndrome, caused by a mutation in the gene that produces a protein responsible for brain and bone tissue health
  • Opitz syndrome, which causes several birth defects affecting the face, heart and larynx
  • Say-Meyer syndrome, which is characterized by developmental delays, problems with motor skills and a short stature

What are the symptoms of metopic synostosis?

Children with metopic synostosis have visible symptoms that include one or all of the following:

  • A noticeable ridge running down the middle of the forehead
  • An overly narrow, triangular shape to the forehead and top of the skull
  • Eyes that appear too close together

Frequently asked questions

Will my child be OK?

The severity of metopic synostosis can vary widely, from mild and barely noticeable to serious and with several complications.

If your child has mild metopic synostosis or just a metopic ridge, he may have no symptoms beyond a visible ridge in the middle of his forehead, and might not need any medical treatment.

However, more serious cases of metopic synostosis can cause complications with:

  • eyesight
  • learning and behavior

Your child’s treating physician will explain the extent of his condition and make specific recommendations for best next steps.

At what age does metopic synostosis tend to develop?

Metopic synostosis is almost always noticeable at birth, but some children—especially those with very mild symptoms—might not be diagnosed until later in infancy.

Is my baby going to need surgery?

That depends on his symptoms and the degree of problems they are causing.

For example, if he only has a noticeable ridge on his forehead but no other symptoms, he probably won’t need any medical treatment at all. But if he has more extensive difficulties, he may need surgery to prevent further problems with his brain and skull growth.

Here at Boston Children’s Hospital, our clinicians have extensive experience performing surgeries for metopic synostosis and all types of craniosynostosis. The vast majority of children who have these procedures go on to lead normal, active lives. 

Questions to ask your doctor

You and your family play an essential role in your child’s treatment for metopic synostosis. It’s important that you share your observations and ideas with your child’s treating physician, and that you have all the information you need to fully understand the treatment team’s explanations and recommendations.

You’ve probably thought of many questions to ask about your child’s metopic synostosis. It’s often very helpful to jot down your thoughts and questions ahead of time and bring them with you, along with a notebook, to your child’s appointment. That way, you’ll have all of your questions in front of you when you meet with your child’s treating clinician and can make notes to take home with you.

Some questions to ask your doctor might include:

  • How did you arrive at this diagnosis?
  • Are there any other conditions my child might have in addition, or instead?
  • How advanced is my child’s metopic synostosis?
  • Is he going to need medical treatment?
  • Is surgery necessary?
  • What is the long-term outlook for my child?
  • Will he need support for any related medical problems?
  • Do I need to make any changes to my child’s daily routines?
  • How should I explain my child’s condition to others?
  • What other resources can you point me to for more information?