The remainder of the myofiber, such as the contractile apparatus and most of the cytoplasm, has largely disappeared. Targets are best visualized on NADH stain. Targets may have clear, dark, or loculated centers. They are especially common in the denervated gastrocnemius muscle. Rods may occur in the center of targets Small fibers that stain darkly on NADH are generally undergoing denervation atrophy.
Atrophic groups are small and contain angular fibers early in denervation.
Small rounded fibers in groups may be seen with chronic denervation. Small fibers are often rounded.