Jean Devroye recently asked Alexandre Duvallet to create a software program to measure the scalp surface area. The software is useful for measuring both the donor area and the recipient area. One can also plot the follicular density in a given area using the software.
The software has it’s limitations, however. The scalp is a curved three-dimensional surface. Photographs are a two-dimensional surface. In order to convert a scalp surface area to a two-dimensional surface area, one must take a clear surface area such as saran wrap, place it on the scalp, and then draw the surface area on the saran wrap with an indelible marker.
The next step is to place the saran wrap on a piece of paper and affix it with either tape or a stapler. Now the 3D surface area has been converted to a 2D surface area. Next, one must take a photograph with a metric ruler in place. The photograph should be a small image size such as 75 to 125 kb. Once the photograph is taken, you load the image into Hairmes.
Next, calibrate the image by marking a specific number of centimeters on the metric ruler using the calibration menu in the software. Once the image is calibrated, you are ready to begin measurement. One simply places a dot on the outline you previously drew on the saran wrap. Then you stop the measurement and the surface area is calculated onto the image. You can save the image and also print the image at this point. The data of the image may also be saved in the Excel worksheet format.
One may also use this software to determine the follicular density of a given surface area. The program is available for both Mac and PC.
Patients find the program useful because it gives the patient a better understanding of the surface area of hair loss. It is useful for physicians in doing presurgery planning and consultation. For example, a patient with 180 square centimeters of hair loss may not fully understand why it is not possible to achieve a full head of hair. If one assumes that coverage is defined by 50% of the original hair density and the patient has 90 follicular units per square centimeter on the top of the scalp, then 45 follicular units per square centimeter would be required to fully graft the top of the scalp. Multiplying 180 sq cm (45 FU/sq cm) = 8100 FU. Clearly this is beyond the capacity of most donor areas. In addition, grafting the crown usually requires a higher follicular density than is required to graft the frontal area in order to get a full appearance. One application of this software is to help patients understand the limitations of the donor area.
You can find more information about this software on their website: Hairmes Hair Transplant Measurement Software