How Much Thickness Can Be Added To The Back Of The Head In An Occipital Cranioplasty?

Q: Dr. Eppley, I am very interested in skull contouring for the back of the head using acrylic, although I do have a couple of questions. What is the maximum thickness that can be added? Where is the incision to put it in located? I have a scar running horizontal across the back of my head from a hair transplant several years back. Can the incision be placed in the existing scar line or is it a must that it be vertical? Thanks for your time.

A: When building up the back of the head (occiput), the limiting factors on the thickness of the augmentation is the scalp and the incisional approach. How much the scalp will stretch is important as its expansion is what creates the space for the material. Usually the augmentation can be anywhere from 10 to 20mms at the greatest point of the arc of convexity. (midline occiput) Where the incision is located and how long it is always influences the shape and volume of the augmentation. While a traditional bicoronal incision provides unparalleled access for any location of skull augmentation, that scar is aesthetically unacceptable. For this reason, I use a vertical incision for an occipital cranioplasty. It provides good exposure over the most important part of the occiput where the buildup needs to be the greatest. Whether your  existing horizontal scar can be used depends on where it is located. Most hair transplant harvest sites are usually fairly low but I would need to see a picture of the scar location to tell if it can be used for incisional access. I would certainly be motivated to try and use it if possible for the obvious aesthetic benefit.
Dr. Barry Eppley
Indianapolis, Indiana