Rimmed Vacuole
A pathological muscle fiber feature consisting of vacuoles with basophilic rims, characteristic of inclusion body myositis and certain hereditary myopathies.
Full Definition
Rimmed vacuoles are pathological structures found within muscle fibers, characterized by membrane-bound vacuoles surrounded by basophilic material that appears as a distinct rim on routine histological stains. These vacuoles contain various cellular debris, including degenerating organelles and protein aggregates. Rimmed vacuoles are a hallmark feature of inclusion body myositis but can also be seen in hereditary inclusion body myopathies, oculopharyngeal muscular dystrophy, and certain other muscle disorders. The basophilic rim represents accumulated ribosomes and rough endoplasmic reticulum, indicating cellular stress and abnormal protein processing.
Usage
Usage note: Hyphenate when used as a compound modifier.
In Context
- "Numerous rimmed vacuoles were present in the muscle biopsy." — Inclusion body myositis diagnosis
- "The absence of rimmed vacuoles argued against inclusion body myositis." — Differential diagnosis