Background: Plagiocephaly is the medical term used to describe a diagonal asymmetry of the head. It is meant to refer to a flatness on either the back or front of the head. But in reality there is always a contralateral flattening opposite the dominant flat part due to the way the skull develops. Hence plagiocephaly is more accurately described as a twisted skull shape where both front and back are affected in varying degrees.
The back of the head is most frequently involved in plagiocephaly. Having seen lots of these cases it affects the right side of the occiput more frequently than that of the left. The flat side of the back of head pushes the ear forward which can be clearly seen from above. The contralateral side of the back of the head may have normal projection or may have some slight overprojection as compensation. Usually, however, the non-flat side of the back of the head is normal in projection.
As an adult the only treatment for occipital plagiocpehaly is surgical. That surgery can only consist of an external augmentation of the bone. The most accurate method is to build an implant for the asymmetry correction based on the shape of the opposite normal side.
Case Study: This young male had a noticeable asymmetry of the back of his head. Even though he had a full head of hair and had never shaved his head, he was well aware its flatness. A 3D CT scan showed the significant amount of right occipital flattening.
From this scan a custom occipital skull implant was designed by mirroring the opposite right side. The thickness of the implant was 14mms over the flattest part.
Under general anesthesia and in the prone position, an 8cm long skin incision was made paralleling the nuchal ridge. The subperiosteal pocket was created and the implant prepared by placing multiple perfusion holes as well etch wedge line internally to permit it to be maximally rolled for insertion. The implant was inserted and positioned using the compass marker on the inferior portion of the implant in the midline.
His immediate intraoeprative result from the prone position shows the complete correction of the occipital asymmetry,
Highlights:
1) Plagiocephaly always involves the back of the head creating an occipital skull asymmetry.
2) A custom occipital skull implant is the most accurate method of correcting an asymmetric skull projection.
3) Such an implant can be placed through a small horizontal incision placed over the nuchal line on the back of the head.
Dr. Barry Eppley
Indianapolis, Indiana