P26 EVALUATION OF HAIR COUNT AND THICKNESS MEASUREMENTS IN MALE AND FEMALE PATTERN HAIR LOSS (ANDROGENETIC ALOPECIA) USING A COMPUTER-ASSISTED TECHNIQUE
Harness JA1, Kohut B2, Garner J1, Canfield W3, Canfield D3, Bertolino AP1
1Pfizer Global Research and Development, Ann Arbor, MI, USA
2Pfizer Consumer Healthcare, Morris Plains, NJ, USA
3Canfield Scientific, Inc., Fairfield, NJ, USA

New digital image technologies and analysis software (DIT) can derive hair thickness measurements that allow Target Area Hair Count (TAHC) determination and a Target Area Hair Width (TAHW) summation measurement. Use of both measures enhances analysis of Pattern Hair loss (PHL) hair parameters and interpretation of data from hair growth treatment interventions. A methodology study was performed using men and women with mild/moderate androgenetic alopecia to assess reproducibility and variability of DIT. Males (Hamilton IV and V; n=50) and females (Savin D3 to D6; n=50) with PHL were studied. Hairs in a 1 cm2 target area were photographed at 3 separate time points (same day) using digital epiluminescence photography (ELP). Target sites with decreased scalp hair density were prepared by clipping hairs to approximately 1 mm in length, prior to ELP. Data for TAHC (hairs/cm2) and TAHW (mm/cm2) across the 3 time points are presented. The mean non-vellus TAHC for men ranged from 170.8 to 172.9 for Hamilton IV and from 124.7 to 128.7 for Hamilton V. For females, the mean TAHC ranged from 176.8-178.1, 145.8-148.9 and 96.8-98.8, respectively, for Savin D3, D4 and D5/D6. The mean non-vellus TAHW for men ranged from 9286.2 to 9432.9 for Hamilton IV and from 6083.5 to 6369.3 for Hamilton V. For females, the mean TAHW ranged from 11303.4-11453.6, 8425.6-8750.2 and 5193.5-5420.6, respectively, for Savin D3, D4 and D5/D6. In summary, the study showed that unit area non-vellus hair count and thickness decrease as the hair loss category increases for both males and females.