Morphological Changes in Extraocular Muscle of Rabbit Eye Produced by Subtenon's Botulinum A Toxin Chemodenervation. |
Byoung Jin Ha, Yong Min Kim, Hyun Seok Kwon, Yoon Hee Chang, Sueng Han Han, Young Kwang Chu, Jong Woon Park, Chan Young Im |
1Siloam Eye Hospital, Seoul, Korea. eyedoc2000@hanmail.net 2The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea. 3Department of Ophthalmology, Ajou University College of Medicine, Seoul, Korea. 4National Health Insurance Coroporation Ilsan Hospital Gyeonggi-do, Korea. 5Department of Ophthalmology, Konkuk University College of Medicine, Seoul, Korea. |
보툴리눔 A 독소 테논낭하 주사가 가토 외안근에 미치는 영향 |
하병진1,김용민2,권현석1,장윤희3,한승한2,주영광1,박종운4,임찬영5 |
Siloam Eye Hospital1, Seoul, Korea The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine2, Seoul, Korea Department of Ophthalmology, Ajou University College of Medicine3, Seoul, Korea National Health Insurance Coroporation Ilsan Hospital4 Gyeonggi-do, Korea Department of Ophthalmology, Konkuk University College of Medicine5, Seoul, Korea |
Correspondence:
Byoung Jin Ha, M.D.1 |
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Abstract |
PURPOSE Currently, when injecting botulinum a toxin into the extraocular muscle, EMG (Electromyography) is used for accurate location. In this study, we examined the effects of subtenon botulinum toxin injection without EMG guidance by quantifying the morphological changes of the extraocular muscle fibers in rabbits. METHODS: Using 10 New Zealand white rabbits, 10 units of botulinum a toxin in 0.1 ml of normal saline was injected into the subtenon space of the superior rectus muscles, 5 mm from the muscle insertion in right eyes. As a control, 0.1 ml of normal saline was injected into the subtenon space of the superior rectus muscles in left eyes. At 3 weeks after injections, the bilateral superior rectus muscles of each rabbit were carefully dissected from the globe. Cross-sections of 5 micrometer thickness were obtained at the site, 5 mm from the insertion of each superior rectus muscle. Sections were stained with Masson's trichrome and observed by light microscopy. Using Image-Pro Plus software, the diameter of the orbital layer myofibers was measured and statistical analysis was done using the Kruskal-Wallis test. RESULTS: The average diameter of the orbital layer fiber cells after botulinum toxin injection was 11.5+/-2.26 micrometer at 3 weeks, whereas that of the control was 14.4+/-3.77 micrometer. The difference was statistically significant (p<0.01). CONCLUSIONS: The diameter of myofibers in the orbital layer was reduced after subtenon botulinum a toxin injection. Further studies on the duration of botulium toxin in subtenon space and the change in the size of myofibers depending on the dosage of botulinum toxin will be necessary. |
Key Words:
Botulinum a toxin;Chemodenervation;Extraocular Muscle;Subtenon's injection |
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