A simple mathematical formula for custom-made croissant tissue expanders.

Abstract

The popularity of croissant-type tissue expanders has increased steadily during the past 5 years. Croissant-shaped expansion offers the advantage of creating a tailored skin flap that is advanced easily into an elliptical skin defect without the formation of dog-ears or without the need for backcuts in the expanded flap. Because the majority of lesions can be considered elliptical in shape, surgical removal is performed easily with an adapted croissant expander. We present a simple mathematical formula for calculating the exact dimensions of the required croissant expander. A good clinical result was obtained using this formula to design large custom-made croissant tissue expanders in a patient with a giant nevus.