Garcia C, Poletti E. Scalp Biopsy Specimens: Transverse vs Vertical Sections. Arch Dermatol. 2007;143(2):264-276. doi:10.1001/archderm.143.2.268-a
Evaluation of hair loss continues to be a challenge for dermatologists and pathologists. Current trend favors the examination of both vertical and transverse sections of scalp biopsy specimens, although it is not clear if this is owing to opinion or evidence. Proponents of transverse sections claim that this approach is better because one can (1) examine more follicles at various levels; (2) determine the total number of terminal follicles; and (3) better appreciate infiltrates. In contrast, those who prefer vertical sections indicate that (1) any structure of the follicle examined with transverse sections can be seen with vertical sections; (2) very few follicles are needed to make the correct diagnosis; (3) the total number of terminal follicles is the least important criterion; and (4) infiltrates can be adequately assessed by pattern recognition.
To gather our own experience we performed a prospective study of 276 Mexican patients whose main complaint was hair loss. Institutional review board approval was obtained. There were 107 male and 169 female subjects ranging in age from 10 to 85 years. Each patient had two 4-mm punch biopsy specimens taken: one for vertical and the other for transverse sectioning under hematoxylin-eosin microscopy. The final diagnoses are summarized in the Table. After analysis, our results can be summarized as follows:
Both vertical and transverse sections were adequate to assess infiltrates and structure of follicles at various levels and to detect clues for diagnosis;
Transverse sections showed more follicles;
Vertical sections were adequate for both scarring and nonscarring alopecias; and
Both vertical and transverse sections rendered a concordant diagnosis in 100% of cases.
In conclusion, we found both vertical and transverse sections adequate for diagnosis of scarring and nonscarring alopecias. Each technique offered some advantages, but neither was superior to the other. The examination of both transverse and vertical sections is beneficial but not essential, and this minimal benefit must be balanced against added costs and/or inconvenience for patients.
Correspondence: Dr Garcia, Department of Dermatology, Oklahoma University Health Sciences Center, 619 NE 13th St, Oklahoma City, OK (firstname.lastname@example.org).
Financial Disclosure: None reported.