Li Yan-na, Mai Guang-huan, Yu Xin-ping, Deng Da-ming, Lin Xiao-ming, Kang Ying, Wang Zhi-jian
Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
Zhonghua Yan Ke Za Zhi. 2004 Oct;40(10):663-9.
To investigate the effect of preserving anterior ciliary vessels (ACVs) on the prevention of anterior segment ischemia syndrome (ASI) during the surgery of extraocular muscles.
Thirty-two adult New Zealand white rabbits were randomly divided into four groups. ACVs of the right eyes were preserved among all of the rabbits, and were cut off in all of the left eyes. Group A: internal and external recti were cut off in two eyes; Group B: superior and inferior recti were cut off in two eyes; Group C: internal, external and superior or inferior recti were cut off in two eyes; Group D: all of the recti were cut off in two eyes. All rabbits were observed under slit microscope. The intraocular pressure (IOP), the total protein and lactic acid in the aqueous humor were recorded preoperatively and postoperatively. Eyes were enucleated at the forth week postoperatively to obtain the iris and the ciliary body for histopathologic study and electron microscopy.
No signs of ASI were observed in the right eyes of all four groups under the slit lamp and under the light and election microscopes. The IOP and levels of ingredients of aqueous humor (total protein and lactic acid) showed no difference between preoperative and postoperative interval. No obvious ASI was observed in the left eyes of group A. Mild reactions of ASI were observed in the left eyes of group B. Moderate to severe reactions of ASI were observed in the left eyes in group C and group D. The IOP reduced from (17.21 +/- 3.76) mm Hg (1 mm Hg = 0.133 kPa) preoperatively to (14.48 +/- 3.36) mm Hg postoperatively in group C (P < 0.05); and from (16.68 +/- 2.33) mm Hg reduced to(3.17 +/- 0.92) mm Hg in group D. (P < 0.05). The level of total protein and lactic acid in the aqueous humor increased from (505.3 +/- 5.0) mg/L and (7.54 +/- 0.47) g/L preoperatively to (811.9 +/- 44.4) mg/L and (11.00 +/- 3.59) g/L postoperatively in group C, respectively (P < 0.05). In group D, the level of total protein and lactic acid in the aqueous humor increased from (504.6 +/- 4.1) mg/L and (7.17 +/- 1.44) g/L preoperatively to (1025. 8 +/- 78.3) mg/L, (8.23 +/- 1.68) g/L postoperatively, respectively (P < 0.05). There were various histopathological changes under the light and electron microscope in groups C and D. While no obvious ischemic changes were observed in group A.
Two vertical muscles cut off at one eye simultaneously would produce mild reactions of ischemia, while three or more muscles cut off simultaneously could obstruct blood flow in eyes and induce ASI. Preservation of the ACVs could avoid the occurrence of ASI.
探讨在眼外肌手术中保留睫状前血管（ACV）对预防眼前段缺血综合征（ASI）的作用。
将32只成年新西兰白兔随机分为四组。所有兔子右眼均保留ACV，左眼均切断ACV。A组：两眼切断内直肌和外直肌；B组：两眼切断上直肌和下直肌；C组：两眼切断内直肌、外直肌和上直肌或下直肌；D组：两眼切断所有直肌。所有兔子均在裂隙显微镜下观察。记录术前及术后眼内压（IOP）、房水中总蛋白和乳酸含量。术后第4周摘除眼球以获取虹膜和睫状体进行组织病理学研究及电子显微镜检查。
在裂隙灯及光镜和电镜下，四组兔子右眼均未观察到ASI体征。IOP及房水成分（总蛋白和乳酸）水平术前与术后无差异。A组兔子左眼未观察到明显的ASI。B组兔子左眼观察到轻度ASI反应。C组和D组兔子左眼观察到中度至重度ASI反应。C组IOP术前为（17.21±3.76）mmHg（1mmHg = 0.133kPa），术后降至（14.48±3.36）mmHg（P < 0.05）；D组IOP术前为（16.68±2.33）mmHg，术后降至（3.17±0.92）mmHg（P < 0.05）。C组房水中总蛋白和乳酸水平术前分别为（505.3±5.0）mg/L和（7.54±0.4）g/L，术后分别升至（811.9±44.4）mg/L和（11.00±3.59）g/L（P < 0.05）。D组房水中总蛋白和乳酸水平术前分别为（504.6±4.1）mg/L和（7.17±1.44）g/L，术后分别升至（1025.8±78.3）mg/L和（8.23±1.68）g/L（P < 0.05）。C组和D组在光镜和电镜下有各种组织病理学改变。而A组未观察到明显的缺血改变。
一眼同时切断两条垂直肌会产生轻度缺血反应，而同时切断三条或更多肌肉会阻碍眼内血流并诱发ASI。保留ACV可避免ASI的发生。
