Background: The back of the head is composed of multiple skull segments of which the occipital bone is a major component. The occipital bone is a non-paired bone that occupies the lower 2/3s of the skull in the back of the head. It is also the primary bone of which many neck muscles attach. As a result of its protective function of the brain and the attachment of the neck muscles it is a thick bone that can protrude outward beyond the natural convexity of the skull. Certain ethnicities and body types are prone to these occipital enlargements. In men that shave their hair or have short hair the shape of the occipital bone has a major influence on the aesthetics of their head shape.
Protrusion or over development of the occipital bone is often called a bun because its central over projection causes it to stick out like a roll or bun rising from a baking pan. While this is a humorous contemporary interpretation of its name the occipital bun has long been considered a Neanderthal feature and probably emanates from the appearance of a twist of hair on the back of the head. Regardless of its name it is a rounded bony projection that is often requested to be reduced.
In most occipital bun reductions the goals is an overall projection reduction with the greatest depth reduction done at its lower half. This is most effectively done with a scalp incision on the bottom side of the knob which also hides it the best. Some patients may, however, request only a part of it to be reduced which may only the upper half of the bun. The incision can then be placed at the upper portion of the bun to do so.
Case Study: This male had a prior history of an occipital reduction from a superior approach. This surgical procedure was satisfactory for him for several years thereafter he desired the lower end of right occipital prominence to be reduced. While its prominence was not externally visible it was palpable as knob and the lower end of the bun.
Under general anesthesia and through a low horizontal scalp incision the bony prominence was exposed. Using a high speed handpiece and burr the prominence was reduced until it felt flat.
With the bone reduced the level of the scalp above the incision fell below the level of the scalp below the incision. This scalp redundancy was removed and closed for a smooth contour.
His back of head contour showed the change and a final complete occipital bun and knob reduction in a two staged procedure.
When enough of the back of the head skull is reduced there is great likelihood that some scalp excess will result. The tightness of the natural scalp does allow for a lot of scalp shrinkage so this must be taken into account when considering any resection. It is also important to limit the length of the incision which is always going to get longer when scalp excesses are removed.
Key Points:
1) The need for secondary occipital skull reduction may occur from an initial subtotaloccipital reduction.
2) Treating the lower half of the occipital bun and/or knob requires an inferior incisional approach.
3) When enough of the occipital skull has been removed a scalp excess can be created… requiring secondary removal.
Dr. Barry Eppley
World-Renowned Plastic Surgeon