In Vivo Visualization of Hair Follicles by Ultrasound Biomicroscopy in Alopecia Areata and Its Correlation with Histopathology

This study assessed the efficacy of ultrasound biomicroscopy (UBM) for visualizing hair follicles in 30 patients with alopecia areata (AA) and compared the findings with histopathology. UBM revealed non-echogenic conical shadows, likely representing hair follicles, which were wider and fewer in AA areas compared to normal areas. There was no significant difference in the number and width of hair follicles between UBM and histopathological examination, although histopathology showed longer follicles, suggesting UBM might not capture the deepest follicle parts. Despite the small sample size, UBM was deemed a useful tool for in vivo visualization of hair follicles in AA.