Muscle Fiber Pathology
- Muscle fiber size is variable.
- Small muscle fibers
- Are rounded or polygonal
- May have abnormal internal architecture
- Endomysial connective tissue is increased.
- Multiple, large internal nuclei may be present within muscle fibers (Right)
Muscle Fiber Internal Architcture
- Irregular, moth-eaten, internal architecture.
- IgM (brown) stains vessels, and muscle basal lamina, endomysium and perimysium, but not muscle fibers.