VERTICAL AND TRANSVERSE SECTIONS OF ALOPECIA BIOPSY SPECIMENS COMBINING THE 2 TO MAXIMIZE DIAGNOSTIC YIELD

Background: Traditional vertical sections of scalp biopsy specimens contain few hair follicles. For this reason transverse sections of scalp biopsy specimens have been advocated. Both methods have advantages and disadvantages. We have developed a simple method that we believe offers the best of both methods. Objective: Our purpose was to assess the impact of combining vertical and transverse sections of scalp biopsy specimens. Methods: Two 4 mm punch biopsies are performed. One specimen is bisected vertically: half for hematoxylin-eosin (H-E) staining, half for direct immunofluorescence. The second specimen is bisected transversely and submitted for H-E. The three pieces of tissue for H-E staining are embedded in a single cassette. Results: Because a biopsy specimen for direct immunofluorescence is commonly obtained in cases of alopecia, our method does not add a surgical procedure. All three pieces of tissue for H-E staining are embedded in a single paraffin block. Therefore the cost of histologic interpretation is not increased. Our diagnostic yield improved. Transverse sections were superior in cases of lupus erythematosus and lichen planopilaris with focal follicular involvement. Features of the follicular degeneration syndrome were also best demonstrated in transverse sections. Interface changes, lupus panniculitis, miniaturized hairs, and trichomalacia were better demonstrated in vertical sections. Conclusion: Our method exploits the advantages of both vertical and transverse sections and improves diagnostic yield without increasing cost.