The flexibility or "elasticity" of the scalp is an important consideration for hair transplant surgeons performing follicular unit strip surgery (FUSS also called FUT). In general terms, the more elastic an individual's scalp is, the greater the number of grafts that can be taken ... and the better the final hair density that can be created for the patient undergoing surgery.
A number of formulas and methods have been proposed to help surgeons calculate elasticity. There are even a number of commercial available instruments and tools that can also be bought to help calculate scalp elasticity.
The Mayer Paul Formula
The Mayer - Paul Formula is a well established method for calculating the elasticity of the scalp. To calculate elasticity on the scalp, two lines are initially drawn 5 cm (50 mm) apart. Then the two lines are compressed together (ideally with the two thumbs). Then, one records how far apart the two lines are after being squished together.
Scalp Elasticity is calculated as
[(50 mm - new position in mm)/50] multiplied by 100 %
VIDEO EXAMPLE: DEMONSTRATION FO THE MAYER PAUL
In this video example, the lines have been squeezed from 5 cm apart to 2.5 cm apart (X = 2.5 for the formula in this example). The elasticity is calculated as 50 %. According to the Mayer Paul formula elasticity of 30 % or more means that a strip of at least 2.2 cm can be taken (if needed) on a first FUT surgery. In contrast, 10 % elasticity means that the strip should be kept less that 1 cm in width
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Vancouver office at 604.283.9299