DENSITOMETRY

Densitometry is a technique that analyzes the scalp under high-power magnification to give information on hair density, follicular unit composition, hair scalp diameter and degree of miniaturization of scalp hairs during the consultation at ProHAIR Transplant Clinic. It can be used to help evaluate a patient’s candidacy for hair transplantation and help predict future hair loss. Multiple measurements taken from different parts of the scalp are often helpful, particularly if there is significant variability from one location to another.

The widespread adoption of Follicular Unit Transplantation (FUT), with its ability to allow for large numbers of follicular units to be safely transplanted in one session, dramatically changed the way modern hair transplantation could be performed. The procedure enabled thousands of follicular units to be transplanted in one session and complete hair restorations to be accomplished in just a few procedures. In order to identify which candidates are suitable for surgery, which may respond best with medications alone, and who can be expected to have more stable hair loss – or become extensively bald – a careful history and physical examination should be performed. This evaluation should not be taken lightly, nor passed off to non-physicians, as the decision to proceed with a surgical solution for hair loss can have a profound impact on a person for the rest of his or her life. With its ability to offer more objective hair measurements, densitometry can play a useful role in this evaluation. Information provided by densitometry are:

1) Hair density -the # of hairs per unit area,

2) Follicular unit density -the # of follicular units per unit area,

3) Hairs per follicular unit – both the range (observed) and the average (calculated),

4) Presence of miniaturization,

5) Hair shaft diameter,

6) Degree of miniaturization,

7) Response to medication and

8) Growth after a hair transplant.

Densitometry showing the natural follicular groupings in the scalp in a person with low density (left), average density (middle), and very high density (right). Note, that as the hair density increases, the average hair count in the follicular unit increases, but the density of follicular units remain relatively constant.