Publication
Tendinous muscle insertions (scleromuscular junctions of the recti muscles) in patients with ocular alignment problems
Journal Paper/Review - Apr 22, 2015
Todorova Margarita, Palmowski-Wolfe Anja M., Meyer Peter
Units
Doi
Contact
Citation
Type
Journal
Publication Date
Pages
Brief description/objective
BACKGROUND: The purpose of this study was to prove the hypothesis whether the scleromuscular junction of extraocular recti muscle is tendinous.
PATIENTS AND METHODS: Muscle samples of the 41 extraocular recti muscles of 33 patients and 4 muscle-/eye-matched samples from 2 postmortem eyes, were processed for light/electron microscopy and immunohistochemistry with antibodies against desmin, smooth-muscle actin and muscle regulating proteins like myf3 and myf4 (myogenin), tenascin C and for 8 samples against collagens I to IV.
RESULTS: Histological examination of the muscle samples confirmed a thick collagen-structured tissue, specific for muscle tendon; without appearance of muscle tissue. This was confirmed by immunohistochemistry with antibodies against desmin, smooth-muscle actin, myf3 and myf4 (myogenin) and for eight samples with collagens I to IV. Anti-tenascin C marker was only strongly positive in the connective tissue of the blood vessel walls. Electron microscopy demonstrated collagen bundles composed of parallel oriented fibrils with a moderate amount of ground substance.
CONCLUSIONS: The absence of contractile fibers at the sclerotendinous junction is an entirely normal finding in humans and cannot be related to ocular alignment pathogenesis.