Background: The skull and head size can be aesthetically increased like almost every other external face and body feature. While fat injections have some role in fat and body augmentations their use in skull augmentations is very limited. And when it comes to skull augmentations of any significant size they are of no value at all as their soft push against a tight scalp cover is poor.
For this reason solid implants are needed to provide enough push to expand the tight overlying scalp using the hard underlying skull bone as a stabile platform to support the implant push. But the stretch of the scalp has its limitations and larger custom skull implants may not fit under the scalp or, even if it can fit under the scalp, the incision may not be able to be safely closed.
This is where the role of scalp tissue expanders has a useful role in an aesthetic procedure. Very similar to their use in extra large breast augmentations the goal is to stretch the overlying soft tissues to accommodate an implant underneath. Similarly, unlike their use in scalp reconstructive surgery, the amount of expansion only needs to be that of the eventual skull implant…which is well known because of the preoperative design.
Case Study: This female desired a large skull augmentation based on preoperative imaging of her aesthetic goals. As a thin female she had a tight scalp and, in addition, her 3D CT scan showed an indentation or groove down the back of her head in addition to having a flatter crown (parietal) skull shape.
A first stage scalp expander was placed and over a four month period she was able to add 250cc of volume into it.
During the expansion phase a custom skull implant was designed to create a large augmentation effect. Its maximum height projection was 17mms with an implant volume of 250ccs. It was designed with a longitudinal split to aid in its placement.
As a second stage procedure under general anesthesia in the prone position the effects of the scalp tissue expander could be seen with the hair parted.
The scalp tissue expander was removed and placing the implant over the deflated expander the footprint similarities between the two could be seen.
After performing bone capsulectomies and surrounding capsulotomies the custom skull implant was inserted, put together and secured with several sutures along the split line and microscrews at its bottom edge.
To check the anterior split line and make sure it was together properly and the anterior capsule was released and the implant edges laying flat, a small scalp incision was made in the supine position to do so.
The two stage approach to large skull augmentation is an effective technique that pushes the implant volumes well beyond what an immediate implant placement can accomplish. It has had no ill effects on the overlying hair and is an absolute requirement for patients who have had a prior hair transplant that involved a strip harvest. Its use is a judgment call on who needs it but, after hundreds of custom skull implant cases over the past ten years, I have a good idea who needs it based on their ethnicity, skin pigmentation and surgical goals.
Key Points:
1) A two stage approach is needed for large skull augmentations to allow an implant volume greater than what the natural scalp can stretch to accommodate it.
2) A first stage scalp expander is needed whose inflation volume should equal the implant design volume.
3) The size of the custom skull implant requires a segmentalized design to allow it to fit through a small scalp incision.
Dr. Barry Eppley
World-Renowned Plastic Surgeon