Background: Scaphocephaly is a general term that literally means a boat-shaped head. Dimensionally this means an elongated front to back head length that is invariably associated with a narrow head width as well. This can occur in non-syndromic patients but the expression of the altered head shape is more mild in presentation than in syndromic cases. Syndromic scaphocephaly always refers to congenital sagittal craniosynostosis which creates a more severe head shape abnormality and is most commonly treated by early cranial vault remodeling surgery.
But untreated sagittal craniosynostosis patients still do occasionally occur and present for head reshaping. Unlike infants and very young children the use of cranial vault reshaping techniques in adults is not going to be effective’s or even practical, given the thickness of adult skull bone and is limited ability to heal gaps in the bone. In adults the narrow skull shape must be treated by augmentation on top of the bone and muscle…in which a good deal of width can be added. The elongation of the skull is still treated by autologous bone manipulations which for reduction involves bone burring. Such front to back reductions are more limited than the head widening that can be achieved. But each dimensional change is synergetic no matter what the magnitude of its effects are.
One of the common misconceptions about alloplastic head widening is that the implant must be placed beneath the muscle on the side of the head. While it is always good to have an implant placed as deep in the tissues as possible to reduce the risk of complications (infection, seroma, implant edging) this doesn’t work forehead widening as the muscle will retract, the amount of implant show will be limited and the augmentation can not cross the bony temporal lines in either the forehead or onto the back of the head. In significant head widening, which is certainly what an adult scaphocephalic head shape needs, it is necessary to cross the bony temporal lines. To do so this requires being on top of the temporal muscle/deep fascia.
Case Study: This adult male was born with sagittal craniosynostosis which was not treated when he was young. He was treated as an adult with some skull reshaping through a bicoronal scalp incision which appeared to be bone burring of the front and back of the head to reduce its length.
By his 3D CT scan a Medpor temporal implant with screws was placed on his left side..but not on his right side.
He presented for further head shape improvement in which a large custom wrap around skull implant was designed. Given its size it was designed in two pieces to aid placement.
The head width increase on each side was 9mms with a total implant volume of 210ccs.
Under general anesthesia and re-opening his bicoronal scalp incision the entire skull was exposed. The temporal muscle and deep temporal fascia were left intact. The custom skull implant was placed and put together with microscrews, Scalp closure was done over a drain on each side.
He went on to fully heal without infection or any problems with incisional healing. He did develop seromas after his drains were removed which requires secondary drain placement to fully resolve.
When seen one year later the significant improvement is his head shape could be seen of which he was very pleased.
In his desire to have an even greater head width augmentation I placed a 5mm onlay temporal implant through a limited incision using the existing scar along the side of his head at one year after the initial surgery.
Key Points:
1) Congenital scaphocephaly in an adult is primarily treated by a custom skull implant with the objective of head widening.
2) The head widening implant can be combined with some limited reduction of the anteroposterior length of the skull.
3) A existing coronal scalp scar provides the ideal access for surgical placement of a large head widening implant.
Dr. Barry Eppley
World-Renowned Plastic Surgeon