游离角膜瓣对LASIK术后角膜散光影响的实验研究
摘要
前言
近视是造成视力下降的常见眼病。中国是世界上近视眼发病率较高的国家之一，其近视眼发生率为50％，并有逐年增加的趋势。
角膜屈光手术从RK，PRK到LASIK走过了一个逐步成熟、完善的过程。LASIK将准分子激光切削组织的精确性和角膜磨削术保持角膜解剖结构的完整性两者的优势充分结合。由于保持了角膜上皮层及前弹力层的完整性，且恢复快，创伤小，无角膜雾状混浊，预测性高等优点，而得到了迅速的发展。
LASIK采用特制微型角膜板层刀在角膜表面先做一个厚度为160um的板层角膜瓣，然后在角膜瓣下进行激光切削。因此，角膜瓣的制作是LASIK成功与否的关键。在某些情况下，可能发生角膜瓣的并发症，游离角膜瓣就是其中较常见的并发症之一。如果术中发生游离角膜瓣，角膜瓣足够大时，可以在瓣下进行激光切削，然后将角膜瓣复位。带蒂的角膜瓣由于有蒂与角膜相连，因此比较容易复位，而游离角膜瓣复位就比较困难。游离角膜瓣的原位复位是否会引起术后角膜散光，已经成为人们关注的问题。
本实验在兔眼的角膜上进行单纯角膜瓣切开制成游离瓣将其原位复位，应用角膜地形图仪观察术后不同时期角膜散光的变化，为临床实践提供理论依据。
方法
选择纯种大白兔13只(26眼)，随机将其分成两组。一组为
实验组，8只大白兔门6眼厂另一组为对照组，5只大白兔（l
眼人所有试验兔术前均分别行裂隙灯检查，以排除角膜及其他
眼部疾病；采用Opp1CON200o型角膜地形图仪对免眼做术前角膜
地形的检测和分析，所有眼角膜散光均小于1．SD，角膜屈光力在
42—45 D之间。
手术操作均由一人完成。手术应用法国产Moria全自动旋
转式角膜板层切割刀，选择角膜瓣的厚度为160urn，角膜瓣直径为
9．smm。实验兔采用全麻，应用846液肌肉注射，用量0．3Im／kg。
表面麻醉采用0．4％倍诺喜滴眼液。先将实验兔用75％的酒精进
行常规消毒，铺无菌孔巾，点一滴倍诺喜眼液进行表面麻醉。开睑
器开睑，在领侧角膜用龙胆紫做定位标记线，用负压吸引环固定眼
球，待负压吸引达180rnmHg时，一组用微型角膜刀在角膜上做一
游离的角膜瓣，另一组制作一个带蒂的角膜瓣，蒂位于上方，然后
依照角膜标记线将角膜原位复位，在角膜瓣下将碎屑用BSS液冲
洗干净，等待角膜干燥后，滴贝复舒眼液，戴眼罩。在角膜瓣制作
时，如果出现角膜瓣撕裂或破碎时即将其弃之。术后将大白兔送
回动物室。术后一周滴泰利必妥眼液，每日4次。
分别于术后7天上周上月上月｝月对术眼进行了角膜地
形图和裂隙灯检查，记录角膜情况，分析游离角膜瓣组与带蒂角膜
瓣组术前、术后不同区域不同时间角膜散光及轴位的变化。采用
SPSS10．0版进行均值t检验。
结 果
所有术眼术后经裂隙灯检查，角膜瓣透明或轻微水肿，水肿
于术后一周消失，角膜瓣对位良好，无角膜上皮层间植人及其他层
间异物，部分角膜缘可见环形混浊。随访期间无一眼在光学区出
现角膜雾状混浊。
实验结果表明，LASIK术中游离角膜瓣组与带蒂角膜瓣组相
·2·
比，术后一周游离角膜瓣组中央 3 mrn区域、旁中央 5 mm区域、周
边7一区域的散光分别为3．56。二．03D、4．“to．99D、5．22 t且．
03D；带蒂角膜瓣组中央3nun区域、旁中央snun区域、周边7rum
区域的散光slJ为二．34 L 0．33D、1．28。0．45D、互．38。0．47D，术
后三个月时游离角膜瓣组中央3rum区域、旁中央srnm区域、周边
7nun区域的散光分另为 2．ZIt 0．62D、2．84。0．59D、3．24。0．
78D；带蒂角膜瓣组中央 3nun区域、旁中央 smm区域、周边 7mxn
区域的散光拥IJ为豆．20 LO．35D、互．13。0．25D、1．10。0．50D。两
组术后角膜散光的差异具有显著性意义河＜0。05人
游离角膜瓣组术后周边处门mm区域）比中心处门 区
域）散光略大，两区域的差异具有显著性意义计＜O．05h而带蒂
角膜瓣组术后7mm区域与3mm区域散光相比，无显著性意义河
＞0．05）。
从本实验术后两组角膜中央3nun区域散光轴位的变化可以
看出，游离角膜瓣组术后散光轴与术前散光轴向之间的差值较大，
术后二周时平均差值为57．3。14．0度，3个月时的平均差值为
35．7 L 13．65度，而带蒂角膜瓣组术后早期方向较乱，二周时平均
差值为 50刀d．94度，1月后逐渐减小，到 3个月时平均差值降
至为 9、4 L 4．92度。
讨 论
LASIK术中游离角膜瓣引起术后角膜的散光，其原因是在手
术过程中虽然我们肉眼看似乎游离角膜瓣对位已经很准确，但是
实际上仍然存在着细微的错位，角膜瓣的错位导致成纤维细胞增
生，产生胶原，新胶原纤维的扭曲生长用E列不齐，在角膜形成了新
的援痕组织，引起了术后的角膜散光；另外，由于角膜为无血管组
织，其营养的供应来自角膜缘血管网、房水及泪液，游离角膜瓣由
于没有蒂与角膜相连接，成为一个游离体，角膜的营养供应明显减
Myopia is a kind of common ophthalmic disease. China is a nation of high - incidence of myopia, where the incidence of myopia is 50% and appears an increasing tendency year after year.
The keratorefractive surgery has been developing from RK and PRK to LASIK and is becoming perfected gradually. LASIK combines the efficacy of excimer laser and the predominance that keratomileusis can keep the epithelium of cornea intact. The superiority of LASIK is that the procedure can keep the epithelium and Bowman membrane intact and postoperative recovery is rapid. Haze is scarce and the predictability of operation is high, which makes LASIK developed rapid-
ly.
Firstly, a 160 um - thick corneal flap is bladed by microkeratome and then photoablation under the corneal flap is performed. Therefore, it is the key of LASIK that preparation of corneal flap. There are corneal flap complications in some case, and free corneal flap is one of them. During preparation of corneal flap, if free corneal flap occurs and is large enough, photoablation can be performed and corneal flap can be replaced. The corneal flap with hinge can be replaced easily, but the reposition of free flap is difficult. Whether the reposition of free corneal flap can cause astigmatism has been put much emphasis on.
Our experiment bladed free corneal flap on the rabbit cornea and
observed the postoperative change of cornea! astigmatism by cornea! topography in order to provide theoretical basis for clinic.
Methods
13 rabbits (26 eyes) were selected and divided into 2 groups randomly: experimental group(8 rabbits, 16 eyes) and control group (5 rabbits, 10 eyes). Before surgery, all of rabbits were examined by slit lamp microscope so as to exclude cornea! and ocular disease. The corneal astigmatism of all eyes was less than 1. 5D and the refractive power was between 42. OD and 45. OD.
All of operations were performed by a doctor. Corneal Flap was bladed by Moria automated rotation microkeratome and 160 um - thick in the diameter of 9. 5 mm. General anesthesia was achieved with 846 muscle - injection (0. 3 ml /kg). Topical anesthesia was achieved with several drops of 0.4% beinuoxi. The eye was disinfected in routine , covered by a piece of scarf with a hole and anesthetized by topical drops. The eye was opened by blepharostat, and then alignment marks were placed on the cornea with methylene blue dye. In the experimental group, the No. 1 suction ring was positioned on the cornea, and a free flap was bladed by microkeratome when the negative pressure value of suction ring reached 180 mmHg. The free flap was replaced carefully according as the alignment mark and was rinsed with BBS solution. After the flap was dried in position for approximately 10 minutes, a drop of beifushu was placed on the eye and a eye patch was wore. In the control group, the No. 0 suction ring was positioned on the cornea, and a comeal flap with upper hinge was bladed by microkeratome when the negative pressure value of suction ring reached 180 mmHg. The flap was replaced and was rinsed with BBS solution. Af-
ter the flap was dried in position, a drop of beifushu was placed on the eye and a eye patch was wore. During preparation of corneal flap, if the flap was incomplete we discarded it. The rabbits were sent back to animal room after operation. Tarivid eye drop was applied to the eye four times a day.
The operated eye was examined by slit lamp microscope and corneal topography at 7 days, 2 weeks, 1 month, 2 months and 3 months after surgery and the state of cornea was recorded in order to analyze the change of corneal astigmatism and axis before surgery and after surgery in experimental group and control group. The data was analyzed by t - test dealt with SPSS10. 0 software.
Results
By slit lamp microscope, we found that the corneal flaps were transparent or a little edema, the alignment of flaps was good, there wasnt epithelial ingrowth but round turbidity occurred on partial corne-a. There wasnt Haze on corneal optical area during following.
The experimental
近视是造成视力下降的常见眼病。中国是世界上近视眼发病率较高的国家之一，其近视眼发生率为50％，并有逐年增加的趋势。
角膜屈光手术从RK，PRK到LASIK走过了一个逐步成熟、完善的过程。LASIK将准分子激光切削组织的精确性和角膜磨削术保持角膜解剖结构的完整性两者的优势充分结合。由于保持了角膜上皮层及前弹力层的完整性，且恢复快，创伤小，无角膜雾状混浊，预测性高等优点，而得到了迅速的发展。
LASIK采用特制微型角膜板层刀在角膜表面先做一个厚度为160um的板层角膜瓣，然后在角膜瓣下进行激光切削。因此，角膜瓣的制作是LASIK成功与否的关键。在某些情况下，可能发生角膜瓣的并发症，游离角膜瓣就是其中较常见的并发症之一。如果术中发生游离角膜瓣，角膜瓣足够大时，可以在瓣下进行激光切削，然后将角膜瓣复位。带蒂的角膜瓣由于有蒂与角膜相连，因此比较容易复位，而游离角膜瓣复位就比较困难。游离角膜瓣的原位复位是否会引起术后角膜散光，已经成为人们关注的问题。
本实验在兔眼的角膜上进行单纯角膜瓣切开制成游离瓣将其原位复位，应用角膜地形图仪观察术后不同时期角膜散光的变化，为临床实践提供理论依据。
方法
选择纯种大白兔13只(26眼)，随机将其分成两组。一组为
实验组，8只大白兔门6眼厂另一组为对照组，5只大白兔（l
眼人所有试验兔术前均分别行裂隙灯检查，以排除角膜及其他
眼部疾病；采用Opp1CON200o型角膜地形图仪对免眼做术前角膜
地形的检测和分析，所有眼角膜散光均小于1．SD，角膜屈光力在
42—45 D之间。
手术操作均由一人完成。手术应用法国产Moria全自动旋
转式角膜板层切割刀，选择角膜瓣的厚度为160urn，角膜瓣直径为
9．smm。实验兔采用全麻，应用846液肌肉注射，用量0．3Im／kg。
表面麻醉采用0．4％倍诺喜滴眼液。先将实验兔用75％的酒精进
行常规消毒，铺无菌孔巾，点一滴倍诺喜眼液进行表面麻醉。开睑
器开睑，在领侧角膜用龙胆紫做定位标记线，用负压吸引环固定眼
球，待负压吸引达180rnmHg时，一组用微型角膜刀在角膜上做一
游离的角膜瓣，另一组制作一个带蒂的角膜瓣，蒂位于上方，然后
依照角膜标记线将角膜原位复位，在角膜瓣下将碎屑用BSS液冲
洗干净，等待角膜干燥后，滴贝复舒眼液，戴眼罩。在角膜瓣制作
时，如果出现角膜瓣撕裂或破碎时即将其弃之。术后将大白兔送
回动物室。术后一周滴泰利必妥眼液，每日4次。
分别于术后7天上周上月上月｝月对术眼进行了角膜地
形图和裂隙灯检查，记录角膜情况，分析游离角膜瓣组与带蒂角膜
瓣组术前、术后不同区域不同时间角膜散光及轴位的变化。采用
SPSS10．0版进行均值t检验。
结 果
所有术眼术后经裂隙灯检查，角膜瓣透明或轻微水肿，水肿
于术后一周消失，角膜瓣对位良好，无角膜上皮层间植人及其他层
间异物，部分角膜缘可见环形混浊。随访期间无一眼在光学区出
现角膜雾状混浊。
实验结果表明，LASIK术中游离角膜瓣组与带蒂角膜瓣组相
·2·
比，术后一周游离角膜瓣组中央 3 mrn区域、旁中央 5 mm区域、周
边7一区域的散光分别为3．56。二．03D、4．“to．99D、5．22 t且．
03D；带蒂角膜瓣组中央3nun区域、旁中央snun区域、周边7rum
区域的散光slJ为二．34 L 0．33D、1．28。0．45D、互．38。0．47D，术
后三个月时游离角膜瓣组中央3rum区域、旁中央srnm区域、周边
7nun区域的散光分另为 2．ZIt 0．62D、2．84。0．59D、3．24。0．
78D；带蒂角膜瓣组中央 3nun区域、旁中央 smm区域、周边 7mxn
区域的散光拥IJ为豆．20 LO．35D、互．13。0．25D、1．10。0．50D。两
组术后角膜散光的差异具有显著性意义河＜0。05人
游离角膜瓣组术后周边处门mm区域）比中心处门 区
域）散光略大，两区域的差异具有显著性意义计＜O．05h而带蒂
角膜瓣组术后7mm区域与3mm区域散光相比，无显著性意义河
＞0．05）。
从本实验术后两组角膜中央3nun区域散光轴位的变化可以
看出，游离角膜瓣组术后散光轴与术前散光轴向之间的差值较大，
术后二周时平均差值为57．3。14．0度，3个月时的平均差值为
35．7 L 13．65度，而带蒂角膜瓣组术后早期方向较乱，二周时平均
差值为 50刀d．94度，1月后逐渐减小，到 3个月时平均差值降
至为 9、4 L 4．92度。
讨 论
LASIK术中游离角膜瓣引起术后角膜的散光，其原因是在手
术过程中虽然我们肉眼看似乎游离角膜瓣对位已经很准确，但是
实际上仍然存在着细微的错位，角膜瓣的错位导致成纤维细胞增
生，产生胶原，新胶原纤维的扭曲生长用E列不齐，在角膜形成了新
的援痕组织，引起了术后的角膜散光；另外，由于角膜为无血管组
织，其营养的供应来自角膜缘血管网、房水及泪液，游离角膜瓣由
于没有蒂与角膜相连接，成为一个游离体，角膜的营养供应明显减
Myopia is a kind of common ophthalmic disease. China is a nation of high - incidence of myopia, where the incidence of myopia is 50% and appears an increasing tendency year after year.
The keratorefractive surgery has been developing from RK and PRK to LASIK and is becoming perfected gradually. LASIK combines the efficacy of excimer laser and the predominance that keratomileusis can keep the epithelium of cornea intact. The superiority of LASIK is that the procedure can keep the epithelium and Bowman membrane intact and postoperative recovery is rapid. Haze is scarce and the predictability of operation is high, which makes LASIK developed rapid-
ly.
Firstly, a 160 um - thick corneal flap is bladed by microkeratome and then photoablation under the corneal flap is performed. Therefore, it is the key of LASIK that preparation of corneal flap. There are corneal flap complications in some case, and free corneal flap is one of them. During preparation of corneal flap, if free corneal flap occurs and is large enough, photoablation can be performed and corneal flap can be replaced. The corneal flap with hinge can be replaced easily, but the reposition of free flap is difficult. Whether the reposition of free corneal flap can cause astigmatism has been put much emphasis on.
Our experiment bladed free corneal flap on the rabbit cornea and
observed the postoperative change of cornea! astigmatism by cornea! topography in order to provide theoretical basis for clinic.
Methods
13 rabbits (26 eyes) were selected and divided into 2 groups randomly: experimental group(8 rabbits, 16 eyes) and control group (5 rabbits, 10 eyes). Before surgery, all of rabbits were examined by slit lamp microscope so as to exclude cornea! and ocular disease. The corneal astigmatism of all eyes was less than 1. 5D and the refractive power was between 42. OD and 45. OD.
All of operations were performed by a doctor. Corneal Flap was bladed by Moria automated rotation microkeratome and 160 um - thick in the diameter of 9. 5 mm. General anesthesia was achieved with 846 muscle - injection (0. 3 ml /kg). Topical anesthesia was achieved with several drops of 0.4% beinuoxi. The eye was disinfected in routine , covered by a piece of scarf with a hole and anesthetized by topical drops. The eye was opened by blepharostat, and then alignment marks were placed on the cornea with methylene blue dye. In the experimental group, the No. 1 suction ring was positioned on the cornea, and a free flap was bladed by microkeratome when the negative pressure value of suction ring reached 180 mmHg. The free flap was replaced carefully according as the alignment mark and was rinsed with BBS solution. After the flap was dried in position for approximately 10 minutes, a drop of beifushu was placed on the eye and a eye patch was wore. In the control group, the No. 0 suction ring was positioned on the cornea, and a comeal flap with upper hinge was bladed by microkeratome when the negative pressure value of suction ring reached 180 mmHg. The flap was replaced and was rinsed with BBS solution. Af-
ter the flap was dried in position, a drop of beifushu was placed on the eye and a eye patch was wore. During preparation of corneal flap, if the flap was incomplete we discarded it. The rabbits were sent back to animal room after operation. Tarivid eye drop was applied to the eye four times a day.
The operated eye was examined by slit lamp microscope and corneal topography at 7 days, 2 weeks, 1 month, 2 months and 3 months after surgery and the state of cornea was recorded in order to analyze the change of corneal astigmatism and axis before surgery and after surgery in experimental group and control group. The data was analyzed by t - test dealt with SPSS10. 0 software.
Results
By slit lamp microscope, we found that the corneal flaps were transparent or a little edema, the alignment of flaps was good, there wasnt epithelial ingrowth but round turbidity occurred on partial corne-a. There wasnt Haze on corneal optical area during following.
The experimental
引文
L David A．Heath．视光学教育：中国需求、全球关注．眼视光学杂志，2000，2(1)，5-6
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5. Wachtlin J, Schuler A, Hoffmann F. Accuracy of corneal lenticules produced for lamellar refractive corneal surgery. Cornea, 1995,14:235
6. Werblin TP. Hexagonal Keratotomy-should we still be trying? J Refract Surg, 1996,12:613-620
7. Seiler T, Holschbach A, Derse M, et al. Complications of myopia photorefractive keratectomy with the excimer laser. Ophthalmology, 1994,101:153
8. Seiler T, Holschbach A, Derse M., et al. Complications of myopic photorefractive keratectomy with the excimer laser. Ophthalmology, 1994, 101; 153-160
9. Sunil S, Anupam C, Stephen JD, et al. Astigmatism induced by spherical photorefractive keratectomy corrections. Ophthalmology, 1997,104:1317-1320
10. CamposM, McDonnell PJ. Photorefractive Keratectomy: astigmatism, In Color Atlas/Text of Excimer laser Surgery. The Cornea. New York: Igaku-Shoin Medical Publishers, 1993,93
11. Gallinaro C,Toulemont PJ, Cochener B, et al. Excimer laser photorefractive keratectomy to correct astigmatism. J Cataract Refract Surg, 1996,22: 557-559
12. Lin RT,Maloney RK. Flap complications associated with lamellar refractive surgery. Am J Ophthalmol, 1999; 127(2):129-136
13. RowsyJJ, ReynddsA, BrownD. Cornealtopography, Corneascope.Arch Ophthalmol, 1981,99:1093-1100
14. Koch DD. The corneal EyeSys system: accuracy analysis and reproducibility of first-generation prototype. Refract Corneal Surg,1989,5:424
15. HershPS, Abbassi R. Surgically induced astigmatism after photorefractive keratectomy and laser in situ keratomileusis. Summit PRK-LASIK Study Group. J Cataract Refract Surg, 1999,25(3):389-398
16. Snibson GR, Carson CA, Aldred GF, et al. One-year evaluation of excimer laser photorefractive keratectomy for myopia and myopic astigmatism. Arch ophthalmol,1995,113:994
17. Gibralter R,Trokel SL. Correction of irregular astigmatism with the excimer laser. Ophthalmology, 1994,101:1310
18．姚晓明(综述)．角膜地形图分析，国外医学(眼科学分册)，1993，17：260
19. Sanders DR, Gills JP, Martin RG. When keratometric measurements do not accurately reflect corneal topography.J Cataract Refract Surg, 1993,19(suppl): 131
20. Cho H,Henry C, Charles C. Immunolocalization of Type Ⅵ Collagen in developing and healing rabbit cornea. Invest Ophthalmol Vis Sci, 1990,31:1096-1101
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22. Taylor DM, L'esperame FA JR, Del pero RA, et al. Human excimer laser lamellar keratectomy; a clinical study. Ophthalmology,1989,96:654
23. Obata H, Takahashi K, Miyata K, et al. Histological and ultrastructual study of rabbit cornea ablated by scannin excimer laser system. Jpn J Ophthalmol, 1994,38:285
24. Dimitri T. Epithelial and stromal wound healing following excimer laser keratectomy. Seminars in Ophthalology, 1994,9:102
25. Shieh E, Moreira H, D Arcy, et al. Quantitative analysis of wound healing after cylindrical and spherical excimer laser ablations.Ophthalmology, 1992,99:1050
26. Colin J, Cochener B, Floch GL. Excimer laser treatment of myopia astigmatism. Ophthalmology, 1998,105:1182-1188
27. Brint SF, Ostrick DM, Fisher C, et al. Six-month results of the multicenter phase I study of excimer laser myopia keratomileusis.J Cataract Refract Surg, 1994,20;610-615
2. Fyodorov SN, Durnev VV. Operation of dosaged dissection of cor heal circular ligment in cases of myopia of mild degree. Ann Ophthalmol, 1979,11:1885
3. Trokel SL, Srinivasan R, Braren B. Excimer laser surgery of the cornea. AM J Ophthalmol,1983,96:710
4. Pallikaris IG, Papatzanaki ME, Stathi EZ, et al. Laser in situ keratomileusis. Lasers Surg Med, 1990,10:463
5. Wachtlin J, Schuler A, Hoffmann F. Accuracy of corneal lenticules produced for lamellar refractive corneal surgery. Cornea, 1995,14:235
6. Werblin TP. Hexagonal Keratotomy-should we still be trying? J Refract Surg, 1996,12:613-620
7. Seiler T, Holschbach A, Derse M, et al. Complications of myopia photorefractive keratectomy with the excimer laser. Ophthalmology, 1994,101:153
8. Seiler T, Holschbach A, Derse M., et al. Complications of myopic photorefractive keratectomy with the excimer laser. Ophthalmology, 1994, 101; 153-160
9. Sunil S, Anupam C, Stephen JD, et al. Astigmatism induced by spherical photorefractive keratectomy corrections. Ophthalmology, 1997,104:1317-1320
10. CamposM, McDonnell PJ. Photorefractive Keratectomy: astigmatism, In Color Atlas/Text of Excimer laser Surgery. The Cornea. New York: Igaku-Shoin Medical Publishers, 1993,93
11. Gallinaro C,Toulemont PJ, Cochener B, et al. Excimer laser photorefractive keratectomy to correct astigmatism. J Cataract Refract Surg, 1996,22: 557-559
12. Lin RT,Maloney RK. Flap complications associated with lamellar refractive surgery. Am J Ophthalmol, 1999; 127(2):129-136
13. RowsyJJ, ReynddsA, BrownD. Cornealtopography, Corneascope.Arch Ophthalmol, 1981,99:1093-1100
14. Koch DD. The corneal EyeSys system: accuracy analysis and reproducibility of first-generation prototype. Refract Corneal Surg,1989,5:424
15. HershPS, Abbassi R. Surgically induced astigmatism after photorefractive keratectomy and laser in situ keratomileusis. Summit PRK-LASIK Study Group. J Cataract Refract Surg, 1999,25(3):389-398
16. Snibson GR, Carson CA, Aldred GF, et al. One-year evaluation of excimer laser photorefractive keratectomy for myopia and myopic astigmatism. Arch ophthalmol,1995,113:994
17. Gibralter R,Trokel SL. Correction of irregular astigmatism with the excimer laser. Ophthalmology, 1994,101:1310
18．姚晓明(综述)．角膜地形图分析，国外医学(眼科学分册)，1993，17：260
19. Sanders DR, Gills JP, Martin RG. When keratometric measurements do not accurately reflect corneal topography.J Cataract Refract Surg, 1993,19(suppl): 131
20. Cho H,Henry C, Charles C. Immunolocalization of Type Ⅵ Collagen in developing and healing rabbit cornea. Invest Ophthalmol Vis Sci, 1990,31:1096-1101
21．刘英奇，赵亮．现代眼科学．南昌：江西科学技术出版社，1996，
109
22. Taylor DM, L'esperame FA JR, Del pero RA, et al. Human excimer laser lamellar keratectomy; a clinical study. Ophthalmology,1989,96:654
23. Obata H, Takahashi K, Miyata K, et al. Histological and ultrastructual study of rabbit cornea ablated by scannin excimer laser system. Jpn J Ophthalmol, 1994,38:285
24. Dimitri T. Epithelial and stromal wound healing following excimer laser keratectomy. Seminars in Ophthalology, 1994,9:102
25. Shieh E, Moreira H, D Arcy, et al. Quantitative analysis of wound healing after cylindrical and spherical excimer laser ablations.Ophthalmology, 1992,99:1050
26. Colin J, Cochener B, Floch GL. Excimer laser treatment of myopia astigmatism. Ophthalmology, 1998,105:1182-1188
27. Brint SF, Ostrick DM, Fisher C, et al. Six-month results of the multicenter phase I study of excimer laser myopia keratomileusis.J Cataract Refract Surg, 1994,20;610-615