The "trichogram" is an older technique developed in 1957 for assessing hair loss. It involves quickly pulling out the roots of 50-70 hairs. The hairs are all placed on a glass slide and examined under the microscope.
By carefully comparing an affected area of hair loss to a presumed unaffected area alot of information can be ascertained. In androgenetic alopecia, there is a marked increase in the proportion of telogen hairs in the frontal scalp (as well as a variation in hair shaft diameter) compared to the occipital scalp. In a pure telogen effluvium the trichogram results are similar in the front and back of the scalp.
A trichogram can provide helpful information in assessing active alopecia area (where an increase in dystrophic hairs are seen) and hair loss from various toxins.
The technique is not commonly used these days as dermoscopy (trichoscopy) has provided a more sensitive and non invasive means of assessing complex scalp disorders.
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