For Bodian staining, if light gray nerve fibers are observed, which adjustment is most likely correct?

• A. Shorten exposure to oxalic acid
• B. Lengthen exposure to oxalic acid
• C. Increase washing steps
• D. Reduce fixative concentration

Answer: (A)

In Bodian staining, the intensity of the dark silver deposits on nerve fibers is influenced by the oxalic acid step, which can bleach or reduce silver. If you see light gray fibers, it means the bleaching step has gone on long enough to remove some of the deposited silver, reducing contrast. Shortening the exposure to oxalic acid decreases that bleaching, so more silver remains on the fibers and they stain darker. This improves visibility and contrast of the nerve fibers.

Longer exposure would bleach more silver and lighten the fibers further, while simply washing more or changing fixative concentration wouldn’t directly restore the dark fiber staining.