[Key-stone mammaplasty. Architectural considerations].
A breast usually has a conical or pyramidal shape. The best way to reduce such a structure is to resect the base. This reduction can be mathematically defined following the principles of the architecture of pyramids. Once the volume is decreased, a conical shape and a stable position has to be recreated. Using the principle of cathedral architecture, a key-stone, is created to stabilise the mammary arch. The architectural study is presented as well as its adaptation to the breast.