Scalp biopsies are valuable when they are taken from the correct area of the scalp, submitted for both vertical and horizontal sectioning and the biopsy is interpreted by an expert dermatopathologist.
The biopsy specimen needs to be taken properly as well. A 4 mm punch biopsy tool should always be used. I always clip the hairs a few mm with scissors before biopsying in order to have a better sense of the angle to place the punch biopsy tool into the skin. One must always place the biopsy tool into the skin at the same angle that the hairs emerge from the scalp ... rather than simply take a sample perpendicular to the skin. Failure to appreciate the correct angle of the hairs as they emerge from the skin will lead to incorrect placement of the punch and many transected hairs in the specimen. In turn, this will create several unique challenges in interpreting the specimen under the microscope.
Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887