Alopecia areata: Line‐field confocal optical coherence tomography features and dermoscopy correlation

Abstract

To the Editor, Alopecia areata (AA) is a common non-scarring disorder characterized by well-circumscribed focal patches of hair loss with an acute or chronic course that can progress to affect all scalp and body hairs. Line-field confocal optical coherence tomography (LC-OCT) is a non-invasive technique that provides high-resolution, vertical, and horizontal in vivo images of the skin with a penetration depth of up to 500 µm. [1][2][3][4][5] It also allows visualization of the upper portion of the hair follicle (infundibulum) that contains the hair shaft [Figure 1A,B].LC-OCT has recently been used for the evaluation of some hair diseases, 6-7 and one study only was done on AA for the monitoring of therapeutic response. 8 The aim of this study was to evaluate by LC-OCT the main dermoscopic findings observed in AA and used to enhance the clinical diagnosis, that is, yellow dots, broken hairs, black dots, exclamation mark hairs, and vellus hairs. 9,10 F I G U R E 1 Normal hair. Vertical (A) and horizontal (B) LC-OCT images show the upper portion of the hair follicle (infundibulum) containing 3 hair shafts (asterisks) with a caliber of 50-60 µm (green bars). The medulla appears high reflective (arrows). Horizontal image (B) is taken at the level of the blue line in A. Insert: dermoscopy of the examined area.