Surgeries for Syndromic Craniosynostosis
What kind of surgery and when to do it depends on each patient’s needs. We perform a limited skull surgery to remove closed cranial sutures if skull pressure is high before 6 months of age. This allows the brain to grow without alleviate pressure and the skull bones to thicken so a definitive open cranial vault expansion can be performed.
Patients with syndromic craniosynostosis have a much greater risk for developing elevated pressure in the skull than non-syndromic craniosynostosis patients. These patients sometimes require an average of 3 or more skull surgeries. The major risk in young patients is blood loss because of their small size and small circulating blood volume. During most surgeries, these patients need blood transfusions.
At Children’s Health, we typically treat syndromic craniosynostosis patients with their first surgery between 6 months and 1 year of age. We operate earlier if there are multiple sutures causing elevated pressure on the brain.
Cranial vault remodeling
The goal of early surgery is to protect the brain, and to protect the airway and the eyes. Usually, the first surgery is to reshape the skull and to increase the space inside to give the brain room to grow into. Open cranial vault procedures require the removal of the skull bones from the outer covering of the brain (dura). This allows the bones to be reshaped and repositioned. The main goal of cranial vault remodeling is to over-correct the skull to treat or to reduce the risk of developing increased pressure in the skull. This allows the brain to grow and improves head shape. While the ultimate goal is to normalize the head shape and overall appearance, these patients have permanent impairments in growth of the skull and facial bones. So even if we overcorrect the position of the skull bones the patients will often outgrow the repair and require another skull expansion. The amount of overcorrection we can achieve is limited by the amount that the scalp will allow.
Cranio vault distraction
The limitations of the scalp in over expanding the skull can be overcome using cranial vault distraction procedures. Distraction osteogenesis is a process where new bone is generated between cut bone edges through the use of a special device (distractor) that slowly moves the bone edges away from one another. This process also stretches the scalp as the bones are moved. Distraction procedures are better for global changes in the size and shape of the skull. While distraction can not be used in all cases, when applicable it can produce more than twice the expansion and change of head shape produced with open cranial vault procedures. It is most commonly used for expansion of the back of the skull, or the forehead together with the middle portion of the face (monobloc). At our institution this is usually the first surgery we perform in patients with syndromic craniosynostosis.
Fronto-orbital advancement (FOA)
This is one of the longest standing procedures used to treat craniosynostosis. This surgery is used to correct the position of the forehead and upper portion of the eye sockets. The longer that we safely can wait to perform the fronto-orbital advancement, the better the chance of the patient having better skull growth and a normal appearance. For this reason, we will perform a posterior cranial distraction as a first procedure and wait for the skull to be close to fully grown before performing the FOA. Sometimes the patient’s eye sockets may be so shallow that the eyelids cannot close enough to protect the eye. If this is not corrected early the patient can have permanent scarring to the eye. If the risk for sight loss is very high, we will either partially close the eyelids with suturing techniques (tarsorrhaphy) or perform a fronto-orbital advancement as out first cranial vault procedure to put the eyelids in a better position to protect the eyes.