The technique shown in the image is most likely Phosphotungstic acid-hematoxylin. Which option corresponds to this technique?

• A. Movat
• B. Phosphotungstic acid-hematoxylin
• C. Giemsa
• D. Silver stain

Answer: (B)

The key idea is recognizing how the stain highlights specific tissue components. Phosphotungstic acid-hematoxylin (PTAH) is a histochemical method that produces a distinctive dark, blue-black coloration of muscle fibers and neurofibrils against a light background. The dark staining of striated muscle fibers (often with visible cross-striations) is a hallmark of PTAH, which helps differentiate muscle and nerve elements from surrounding tissue.

Movat pentachrome, by contrast, uses multiple colors to differentiate several tissue types on a single slide; Giemsa gives purplish-blue staining of nuclei and cytoplasm in blood-related cells and parasites; and Silver stains yield black deposits on reticular fibers, basement membranes, and certain nervous tissue structures. The image pattern described is characteristic of PTAH, so the technique shown corresponds to Phosphotungstic acid-hematoxylin.