Background: There are a variety of types of narrow head shapes which vary based on the extent of bitemporal width reduction and how it affects the shape of the front and back of the head. In more complete manifestations the head is narrow from front to back and either the forehead or the parieto-occipital is also lacks adequate width or roundness. When the narrowness affects the back of the head this creates for the patient a lack of skull projection in the oblique views with a flattening of the temporal lines and a reduced crown and top of the head height.
In these more extended forms of narrow head shapes a horse shoe type of skull augmentation is needed. This can be created by a custom skull implant design using the patient’s 3D CT skull scan. While it is ‘easy’ to design any implant on the computer screen it is often quite a different matter to surgically place it. In placing these extended surface area coverage skull implants there is not the luxury of having full visualization of their placement using a long scalp incision. Rather, because it is an aesthetic operation, small scalp incisions need to be used that can heal in an inconspicuous manner. As a result how can such a large implant fit through them?
Case Study: This male was bothered by a narrow head shape that began at the top of his forehead extended back along the sides of his head to the crown area. He felt the greatest deficiency was at the top back of his head and became less so as it came forward. His skull deficiency was most apparent to him in the three-quarter or oblique views. His 3-D CT scan confirmed the parasagittal temporal deficiency with flatness at the upper back of the head.
Using his 3D CT scan custom head widening implants were designed to widen the side of his head as well as add some fullness to the upper back and top of the head. For placement purposes it was designed in two pieces to pass through a small scalp incision with a midline geometric split line. The total two piece implant volume was 151ccs.
Of note in the skull implant design it covered the upper or the parasagittal region of the temporal sides of the head only… which is very consistent with the deficiency seen in the 3D CT scan.
In the prone position under general anesthesia a plastic model of the two piece implant was placed on the patient’s head to have accurate idea as to how it was o be placed on the head as well as where to place the scalp incisions to do so.
The custom skill implant was a two-piece design of which its midline e split was critical for its placement. The interdigitating sawtooth design is a critical part of the split as its reassembly once inside the scalp pocket relies on this reconnection to be externally felt.
A small scalp incision was made in the upper back of the head. Then using long sub periosteal elevators the entire scalp on the top sides and back of the head was elevated to create the implant pocket. This aided by a very small incision located just behind the frontal hairline.
The two pieces of the implant were inserted and pieced back together by external feel of the split line through the scalp. To aid the union of the two pieces of the implant anteriorly the small frontal incision was very helpful. At these two incision sites the implant was secured with sutures and micro screws. The scalp incisions were closed over a drain with resorbable sutures in two layers.
His immediate intraoperative result showed the increased forehead and side of the head width in the back and top views.
When most think of skull augmentation they think of a rounder more convex implant often used to augment a flat spot on the head. But head widening implants are longer and thinner and cover a much larger surface area. This poses some unique considerations in the tissue pocket dissection and implant placement. Since there are two sides to the head the implant design can be though of as two halfs which can be reunited once inside the pocket to create the full head reshaping effect.
Key Points:
1) The narrow shaped head has a decreased bitemporal width that often extends onto the back of the head.
2) The narrow head can be widened by extended skull implants that wrap around the sides and back of the head for posterior augmentation as well.
3) Such head widening wrap around custom skull implants have to be designed and inserted in pieces to keep the scalp incisions limited.
Dr. Barry Eppley
World-Renowned Plastic Surgeon