Drug-induced Extraocular Myotoxicity Associated with Diplopia after Cataract Surgery.

Oh, Joo Yeon; Lee, Kwang Gil; Rah, Sang Hoon

Original Article

Journal of the Korean Ophthalmological Society 2003;44(6):1414-1420.
Published online June 1, 2003.

Drug-induced Extraocular Myotoxicity Associated with Diplopia after Cataract Surgery.

Joo Yeon Oh, Kwang Gil Lee, Sang Hoon Rah

¹Department of Ophthalmology Yonsei University College of Medicine, Wonju, Korea. shrah@wonju.yonsei.ac.kr
²Department of Pathology Yonsei University College of Medicine, Wonju, Korea.

백내장 수술 후 복시증과 연관된 외안근의 약물 독성

오주연 ( Joo Yeon Oh ) , 이광길 ( Kwang Gil Lee ) , 라상훈 ( Sang Hoon Rah )

Abstract

PURPOSE
To assess the myotoxicity of local anesthetics and antibiotics which are considered as the main causes of diplopia and extraocular motility disturbance following cataract surgery. METHODS: A total of 48 rabbits were classified into 4 groups. The control group received an injection of 0.3 ml normal saline in the subconjunctival space above the superior rectus muscle. The first experimental group received an injection of the same amount of a local anesthetic (2% lidocaine) in the same manner as the control group. The second group received an injection of 0.3 ml of a local anesthetic directly into the extraocular muscle (superior rectus muscle), the third group received an injection of 0.3 ml of an antibiotic (gentamicin) in the subconjunctival space above the superior rectus muscle. Histologic and electron microscopic changes following injections were compared over time in each group. RESULTS: Light microscopic findings showed that subconjunctival injections of antibiotics caused the most severe inflammatory and fibrotic reactions of the muscular fascicle, whereas subconjunctival injections of local anesthetics led to the least damage of the muscular fascicle and less infiltration of inflammatory cells. Changes in histological findings showed that necrotic muscle fibers and inflammatory cell infiltration at 1 week following injections. Basophilic myogenous satellite cells indicating regeneration of the damaged muscles appeared thereafter. At 2 and 4 weeks, the group injected with antibiotic showed local and consistent infiltration of inflammatory cells and fibrosis, whereas the groups injected with anesthetics showed regeneration of most of the damaged fascicle. CONCLUSIONS: In terms of temporary or permanent diplopia following an injection of local anesthetics or antibiotics after cataract surgery, toxicity of anesthetics or antibiotics on extraocular muscle is the main cause from these Results.

Key Words: Diplopia;Gentamicin;Lidocaine;Myotoxicity