Improving Hair Count Assessments with Digital Imaging

by Kevin Rands | May 17, 2016 4:08 am

Quantifying progression or reversal of follicular miniaturization in androgenetic alopecia by image analysis.

Authors:

David A. Whiting and Douglas Canfield
Baylor Hair Research and Treatment Center

Study Information and Results:

Histologic analysis of horizontal sections of scalp biopsies in men and women with androgenetic alopecia is an established method of measuring progression of hair loss or hair regrowth. Detailed follicular counts are time consuming, making this technique problematic for large drug trials. Digital imaging can provide reproducible information which can be more precise than that derived from visual microscopic examination.

A method of image analysis was developed to quantify follicular counts and to size individual follicles. A Nikon D1 digital camera was attached to an Olympus BX 40 microscope. The apparatus was linked to a Dell Dimension XPS T500 desktop computer. An imaging program was used, and data was handled with automated computer analysis.

A large number of biopsies from different trials were studied. These biopsies had already been evaluated by visual histologic analysis with the observer blinded to time and treatment. All biopsies were re-photographed with the digital camera using a 2x magnification objective. The entire 4 mm cross-section of a biopsy was photographed. The images were stored and examined later with similar observer blinding. All terminal and vellus hairs visible in the papillary dermis were marked by the investigator.

A technician then mapped each cross-sectional hair shaft area and automated image analysis was performed. Total hairs in each section were counted. Hairs were classified into four different groups. The cross-sectional size varied from vellus-like hairs through intermediate hairs and small terminal hairs to large terminal hairs. This quantification could yield an average hair diameter for the entire section and also enumerate the hairs of different diameters to reflect different stages of the miniaturization process.

The results were analyzed in both active treatment and placebo groups. They could also be compared to the previous results from the standard visual follicular counts in histological sections.

Summary:

This study was performed in an attempt to improve the method by which hair counts, and treatment progress is ascertained in clinical studies. Typically manual microscopic hair counts are performed, which are tedious, time consuming, flawed, and expensive. The investigators in this study used Digital imaging to provide reproducible information which can be more precise than that derived from visual microscopic examination. A method of image analysis was developed to determine hair counts and to size individual follicles. A Nikon D1 digital camera was attached to an Olympus BX 40 microscope. The apparatus was linked to a Dell Dimension XPS T500 desktop computer. An imaging program was used, and data was handled with automated computer analysis.

Source URL: https://www.hairlosstalk.com/studies/research-methods/improving-hair-count-assessments-digital-imaging/