When one thinks of cosmetic surgery, the thought rarely goes to any form of skull contouring. While the world is full of a wide variety of head shapes, there is no uniform size or measurement to determine a pleasing cranial contour. But there is a certain oblong and curvilinear shape to most of the skull. The forehead, which is really the front part of the skull, has some very specific desired shapes and contours that are very gender-specific, but the rest of the skull has less well-defined determinants of being pleasing in appearance.
Despite the comparatively obscure location of the back of the head (occiput) compared to the forehead, not everyone is entirely pleased with this portion of their skull shape. The typical concern is that the back of the head is too flat without adequate projection. Whether it be the entire occiput or limited to just the crown area (upper occiput), this is a legitimate cosmetic concern for those so affected. For anatomic clarification, the bony portion of the occiput actually stops at about the level of the middle of the ear. The rest of the back of the head is muscle and other soft tissue.
The most effective method of occipital skull contouring is augmentative, putting a material on top of the bone to build it out. This is a common form of cranioplasty that has a long history in the forehead, it is just less commonly done on the back of the head. There are multiple ways to perform an occipital augmentation cranioplasty and they differ primarily in the material used and the incisional approach to get it there. Each has their own distinct advantages and some disadvantages.
The open form of an occipital cranioplasty uses a straight line vertical incision of about 3 or 4 inches down the back of the head. This approach heals better than any other scalp incision in this area. The scalp is lifted off of the bone around a premarked area of the flattening. Through this approach, either an acrylic (PMMA) or calcium hydroxyapatite (HA) material can be mixed, placed and contoured to the desired shape. Both are powders and liquids that are mixed together to form a moldable putty which as about 10 minutes of working time. Because it is a putty, thus is why it needs an open approach to be placed. Acrylic has the advantage of setting up as solid as bone and just as fracture-resistant. That would offer a theoretical advantage on the back of the head since we lay on it all the time. HA, which setting up firm, is a bit more brittle and fracture-prone although I have never seen that to be a problem in the forehead. With either material, the open approach offers the best chance for a very smooth and even contour shape.
The limited incision or injectable approach uses a small one inch incision through which a material is injected by a small tube. (not a needle) The only cranioplasty material that has the physical properties once mixed (for the first 4 minutes) to flow through a small tube is Kryptonite. (KP) This is a calcium carbonate material that is also highly compatible and will allow some skull bone ingrowth. It does not get as hard as PMMA but it slightly less brittle than HA. The disadvantage to the injected material approach is that there is a higher risk of contour irregularities and palpable edges. This occurs because the molding of the material as it sets is done from the outside so there is no visual way of confirming how smooth it is as it sets.
Cosmetic contouring can be done on most areas of the skull. Occipial augmentation cranioplasty can be done to build out a flat spot or entire back of the head. Regardless of the material and the incision used, it is a simple procedure for a patient to go through with very minimal recovery. Patients report having a headache for a few days but no real pain. Once can wash their hair within 48 hours. Some mild swelling can be expected and the final result can be fully appreciated within 6 weeks after the procedure. All of the cranioplasty materials used are permanent so the change in skull contour will be maintained over one’ lifetime.
Dr. Barry Eppley