Which chemical method is used as an alternative to demonstrate the tissue component stained black in the image?

• A. Aldehyde fuchsin
• B. Orcein
• C. Verhoeff's stain
• D. Masson's trichrome

Answer: (A)

Elastic fibers can be visualized with several stains that turn them dark, almost black. The classic method for highlighting elastin is Verhoeff–Van Gieson, but aldehyde fuchsin offers a reliable alternative to demonstrate the same component with a strong black coloration. Aldehyde fuchsin is specifically used to stain elastic fibers, providing a crisp contrast against the background, which makes it a good substitute when Verhoeff’s stain isn’t used. This is why it’s the best choice here: it directly targets elastin and reproduces the dark staining seen in the image.

Masson's trichrome mainly stains collagen and muscle rather than elastin, so it wouldn’t highlight the same component. Orcein also stains elastic fibers but can yield a different hue and contrast, whereas aldehyde fuchsin is widely recognized as a standard alternative for demonstrating elastin in tissue sections.