Repairing the Skull

Pediatric Neuro News
March 31, 2013

In developing minimally invasive approaches and 3-D surgical planning, Johns Hopkins has created a center of excellence for children with craniosynostosis.

Edward Ahn, MD, Amir Dorafshar, MD

To give craniosynostosis patients the best outcomes, pediatric neurosurgeon Edward Ahn, left, and plastic surgeon Amir Dorafshar use skull models derived from CT scans and 3-D virtual surgical planning programs.

Mother Nature was wise in not attaching the skull’s bony plates at birth, allowing the infant’s head to expand in all directions in the months ahead to accommodate the rapidly growing brain. But in some babies, the plates fuse prematurely, constrict skull growth in one direction and force the skull to grow excessively in other directions, a condition known as craniosynostosis. The traditional treatment, typically performed when a child is between 6 months and a year old, has been open surgery to break up and reconstruct the plates, but it’s a long operation requiring an ear-to-ear incision as well as transfusions to compensate for considerable blood loss.

“It’s almost a week in the hospital, and it may require additional surgeries to improve the results,” says Johns Hopkins pediatric neurosurgeon Edward Ahn. “Neurosurgeons really wanted to rethink the approach.”

Ahn did just that starting five years ago, utilizing a minimally invasive approach in which he makes only two tiny incisions on an infant’s head to accommodate an endoscope and a tiny cutting tool for removing a thin strip between the plates to free them. The procedure is so fast and neat that transfusions usually aren’t required, and the infant can go home the next day. And it can be performed on children as young as one month, an age at which all the plates are still shifting, resulting in improved outcomes in the shape of the skull.

“The sooner you release the restriction that the craniosynostosis is causing,” says Ahn, “the sooner you allow the brain and skull to develop as they normally would.”

Now, for older babies diagnosed with craniosynostosis that requires an open approach and cranial remodeling, Ahn and plastic surgeon Amir Dorafshar are offering another treatment advance—3-D surgical planning. First they upload images from the patient’s CT scan to a computer software program that allows them to see all angles of the patient’s skull in three dimensions. Via this virtual tool, they begin to plan and simulate the surgical cuts that will both minimize the patient’s risk of bleeding and maximize efforts to achieve the most natural skull shape. Next, plastic templates are produced from the 3-D simulation for placement on the patient’s skull during the surgery, giving the surgeons precise cutting guides.

ADVERTISEMENT

“Before, we used to do these line drawings, based on anatomical features, of where we would move the bones to make the skull look more normal,” says Dorafshar. “Now, through computer-assisted modeling, we’re able to simulate the reconstruction, which allows us to move the bones exactly to where we want them to be. We know where things are and can plan accordingly to make our cuts safe and have as normal a skull as possible.” 

For information: 410-955-7337