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探讨显微板层角膜切削术治疗表层角膜病变的可行性。方法以新西兰白兔为实验动物,以切削直径7.5mm、4.0mm和切削深度120μm、60μm为手术参数,随机将实验动物分为4组,行MLK,手术10天、1、2、3、6个月检测术眼角膜的屈光度,透明度及角膜神经和上皮的组织修复情况。 相似文献
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准分子激光角膜切削中心的角膜地形图分析 总被引:10,自引:0,他引:10
目的探讨准分子激光角膜切削术(photorefractivekeratectomy,PRK)的切削中心对视功能的影响。方法采用Eyesys角膜形态分析系统对随访6个月以上的98例(158只眼)PRK前、后10天的角膜地形图进行分析,确定激光切削中心相对入射瞳孔中心的方向、距离;比较单区和多区域激光切削的偏中心差异。结果切削区中心相对入射瞳孔中心:0~0.5mm者100只眼(63.3%),0.5~1.0mm者55只眼(34.8%),>1.0mm者3只眼(1.9%),平均0.45mm。多区域切削38只眼及单区域切削120只眼,其偏心量分别为0.55mm和0.44mm。差异有显著性(t检验,P<0.05)。偏中心切削致术后最好矫正视力下降1~2行者4只眼,其偏心量>0.5mm。结论严重的偏心切削将影响术后视功能恢复,术中眼球跟踪系统(passiveeye-tracking,PET)的应用有利于切削中心的确定,减少偏心量。 相似文献
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17例近视患在准分子激光切割术后第一年中进行了计算机辅助的角膜地形图的分析。角膜中央视区进行了自然过渡到周边角膜的切削。在一些眼出现切割偏中心(3眼小于0.5mm,10眼为0.5~1.0mm,3眼为1~1.5mm,1眼为2.1mm),说明瞄准光束是非常重要的。有待改进使切削中心位于瞳孔中心。17眼中的12眼在PRK术后3~7个月内角膜地形图非常稳定,其余的5眼在6~12个月的随访时,发现中央屈光 相似文献
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准分子激光原位角膜磨镶术后角膜地形图分析 总被引:12,自引:0,他引:12
为分析准分子激光原位角膜磨镶术后角膜地形图的动态变化,随访LASIK后1月病人共137例(196眼),术后3月48例(70眼)。采用随机扫描式消融角膜基质。术后用0.3%氟嗪酸,0.1%FML滴眼10天。记录术前、术后1个月、3个月的视力,屈光度数,角膜地形图。结果:术后1月角膜表面规则系数、角膜表面非对称系数明显大于术前,术后3月无明显改善。术后1月切削形态中平滑型占89.8%,其他形态占10.2%。切削形态随时间延长逐步变规则。术后切削中心平均偏心0.67±0.48mm(0~2.24mm),偏心距离在1mm以内对最佳矫正视力影响不大,偏心方向以鼻侧居多。结论:LASIK手术由于保持了角膜上皮层及前弹力层,术后角膜及切削形态较规则,但仍然存在偏心切削的问题。角膜地形图为临床评估LASIK效果提供了客观依据。 相似文献
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人工晶体植入术后早期角膜地形图的变化 总被引:3,自引:0,他引:3
目的 为了解白内障囊外摘除及人工晶体植入术后早期切口对全角膜弯曲度的影响。方法 用TMS-1型角膜地形图,记录经长约11mm阶梯状角膜缘切口行白内障摘除及后房型人工晶体植入术的42只眼,在术后3个月内角膜屈折力及其图形变化。结果 术后角膜地形图均呈现以角膜顶点为中心纵向“哑铃形”图形改变,表示垂直经线各部位的角膜变陡,屈折力增加,中央2.5mm 半径处显著大于1.5及3.5mm处,上象限大于对应的 相似文献
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Optisol角膜保存法 总被引:2,自引:0,他引:2
Optisol系一种新型的角膜保存液,其保存效果优于M-K液、K液、CSM及Dexsol液。应用Optisol液保存的供体角膜水肿明显低于Dexsol液。应用Optisol保存1-8天之供体角膜行穿透角膜移植术,术后3月至半年植片透明率为79.1%,10例患者术后行角膜内皮镜检查,植片中央内皮细胞密度为1030-2460个/mm2。 相似文献
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不同降温速度对保存的角膜内皮细胞活性的影响 总被引:3,自引:1,他引:3
目的通过调节程序控制降温仪的降温速度保存兔角膜,以提高保存角膜的内皮细胞的存活率(ESR)。方法供体角膜150只随机分为对照组和实验组。对照组不做冷冻处理;实验组冷冻147只角膜,带巩膜缘1~2mm的角膜片分别在4种不同浓度梯度的冻存液中预处理各10min,再经过两个阶段(0~-18℃,-18~-80℃)49种不同程序逐步降温至-80℃,最后放入液氮中保存。1个月后水浴复苏供体角膜,洗脱冻存液、染色、同定,行镜下形态学观察并计算角膜内皮细胞存活率。结果镜下观察第一阶段降温速度为2℃/min、第二阶段降温速度为5℃/min时的方法较好,计数细胞的存活率达到75%以上,与其他不同速度下比较差异有统计学意义(P〈0.05)。结论不同阶段不同降温速度下,深低温保存兔角膜对角膜的内皮细胞存活率有明显影响。 相似文献
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角膜盲占全国盲人的四分之一,角膜移植手术是治疗角膜盲唯一有效方法,受供体角膜材料来源限制,我国目前每年施行角膜移植手术仅1000多例,与现实要求差距很大。探讨开拓供体角膜材料来源问题,有着十分重要的现实意义。提及我国供体角膜材料来源的现状、存在问题及解决问题的若干对策,冀望这一问题能早日解决,以推动我国角膜移植手术的开展。 相似文献
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7例12眼高度近视,通过角膜内定量切除一薄片板层组织盘(直径4mm,深度按8μm矫正1D)以改变角膜前表面曲率半径的设计达到屈光矫正效果。术后3 ̄9个月的随访表明,所有术眼被矫正到接近正视状态。此新型手术的最大优点是,屈光矫正不需供体角膜,能在患眼中通过削薄角膜,重塑角膜的屈光状态。如能完善手术器械,则可在国内普及推广,是屈光性角膜成形术中一项极有希望的尝试。手术安全度大。缺陷是手控式环钻难以达到 相似文献
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PURPOSE: The role of complement in phagocytosis and killing of P. aeruginosa was examined using serum from aged vs young donor mice. METHODS: Phagocytosis, complement hemolytic and microbicidal assays were used. RESULTS: Serum from young donor mice contained a heat-labile factor which significantly enhanced phagocytic activity of cells from young mice compared with similarly treated aged donor serum. Use of cobra venom factor (CVF) to destroy C3 and the terminal complement components in serum from young or aged donor mice also significantly decreased the phagocytic activity of young cells. EGTA treatment of young or aged donor serum, to activate the alternative pathway and selectively inhibit activation of the classical pathway, resulted in a significant decrease in phagocytosis by young cells in the presence of donor serum from either group. Alternative pathway mediated hemolysis also was measured and was significantly reduced in aged vs young donor serum. PMN microbicidal activity was tested using cells from young mice in the presence of aged vs young donor serum, but no significant differences were noted. CONCLUSION: These data provide evidence that defects in the alternative pathway of complement in the serum of aged animals lead to decreased phagocytic activity of cells from young mice, but not impaired bacterial killing. 相似文献
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With donor material kept under banking conditions, corneal grafting is today an elective routine surgical procedure. Increasing evidence suggests that the clinical results may be improved by HLA matching. However, serological tests require that a blood sample be taken while the donor is still alive or shortly post mortem. We report HLA-DR donor typing with a DNA hybridization technique using DNA isolated from the donor eye more than 24 h post mortem. The practical implications of this procedure are briefly discussed. 相似文献
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Microkeratome-assisted posterior keratoplasty 总被引:6,自引:0,他引:6
Microkeratome-assisted posterior keratoplasty is a new surgical technique that may be valuable in treating patients with corneal decompensation secondary to endothelial dysfunction. A hinged anterior stromal flap is fashioned in the host cornea using a microkeratome, and the diseased posterior stroma and endothelium are resected. A complementary donor stromal button is prepared using a microkeratome and an artificial anterior chamber. The donor button is transplanted and secured with sutures, and the flap is repositioned. The flap can be lifted later to remove the sutures or to correct residual refractive errors using an excimer laser. This technique may allow the use of infant corneal donor tissue and may improve the outcomes of posterior keratoplasty. 相似文献
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Koenig SB Dupps WJ Covert DJ Meisler DM 《Journal of cataract and refractive surgery》2007,33(2):189-190
We describe a technique to facilitate unfolding and prevent inversion of the donor corneal lenticule during Descemet's stripping and automated endothelial keratoplasty (DSAEK). The donor corneal lenticule is unfolded in the anterior chamber using a bent 30-gauge needle on a 3 cc air syringe. The needle tip is used to pinion the edge of the lenticule while an air bubble is simultaneously injected between the folded edges of the donor graft. A gentian-violet dye mark placed on the peripheral stromal surface of the donor lenticule is used to confirm proper graft orientation. The simple technique of simultaneously fixating the donor lenticule while injecting air ensures that the graft unfolds correctly and minimizes potential mechanical trauma to the endothelium. 相似文献
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目的 为提高角膜材料的利用率,探讨将同一噶供者的二个角膜同期移植给不同受者的可行性及手术方法.方法 供者的其中一个角膜材料分别为1例角结膜恶性黑色素瘤,1例蚕蚀性角膜溃疡伴穿孔行前部分板层角膜移植术,并对1例大泡性角膜病变行深板层角膜内皮移植术.另一个角膜材料分别为眼烧伤后重度睑球粘连行全板层角膜移植和1例大泡性角膜病变行深板层角膜内皮移植术.结果 5例角膜病患者手术均获得成功,其中2例大泡性角膜病变患者术后1个月,角膜上皮水泡消失,角膜水肿减轻,内皮植片透明.1例角结膜恶性黑色素瘤患者,视力术前0.3提高至术后0.6,植片透明,角膜植床及结膜无色素残留.1例蚕蚀性角膜伴穿孔经羊膜移植联合部分板层角膜移植治愈.1例眼烧伤睑球粘连患者,术后1个月,睑球粘连完全解除,植片透明,视力由术前0.1提高到0.3.结论 将同一供者的角膜分别移植给不同受者,能充分利用供者角膜材料,方法可行,效果良好. 相似文献
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Forty-one consecutive aphakic corneal transplants performed by the same surgeon were stuided in order to determine the effects on intraocular pressure and corneal curvature of using 8.0-mm donor buttons in 7.5-mm recipient openings. One half of the grafts had oversize donor buttons, and all were followed for 13 months. The intraocular pressure in the oversize donor group was statistically significantly less during the first five days after keratoplasty, but not subsequently. Eliminating eyes with preoperative glaucoma, more transplants in the same size donor group (P = 0.08) needed glaucoma therapy 13 months after operation. The anterior corneal curvature (mean keratometry reading) was statistically significantly greater in the oversize donor group throughout the postoperative period. Concurrently, the oversize donor group was less hyperopic after all sutures were removed. There was no difference in keratometric astigmatism or corneal thickness between the two groups. Thus, the use of 0.5-mm oversize donor tissue in aphakic corneal transplants reduced the intraocular pressure and increased the central corneal curvature after keratoplasty. 相似文献
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Omar Kirat 《Ophthalmic surgery, lasers & imaging》2007,38(3):254-256
A new technique is described to easily and accurately mark the donor and the host cornea in keratoplasty using simple, readily available instruments and utilizing a simple mathematical equation. This technique will allow for even distribution of the donor tissue in the recipient bed. 相似文献
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Akagi T 《Seminars in ophthalmology》2005,20(1):11-15
While a number of retinal transplantation studies using various types of donor cells have been performed thus far, our study focused on iris tissue as a donor cell source. This is because donor cells from iris pigment epithelium have the following characteristics: (1) they are embryonically related to the neural retina; (2) autologous iris tissue can be obtained via a surgical approach; and (3) they can be cultured to increase the number of donor cells and establish photoreceptor-like cells from iris-derived cells by means of the appropriate gene transfer. Although the potential of iris-derived cells has been indicated, there remain many issues to be investigated. 相似文献
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D R Kulwin R C Kersten M P Gingold A Hornblass 《Ophthalmic plastic and reconstructive surgery》1989,5(1):59-62
Suturing is the usual method employed to close retroauricular skin graft donor sites. We present our 8-year experience with 163 cases demonstrating that such donor sites can be closed with equal efficacy using skin staples. This technique is simple and takes less surgical time. 相似文献
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AIM: To describe the design and clinical application of a corneal donor dehydrator which can quickly dehydrate corneas and keep its original shape.
METHODS: The corneal donor material is placed on stainless steel beads with different diameters in the dehydrating box to make the cornea the same shape as the steel ball. Then, the cornea is placed inside the dehydrater for rapid dehydrating using the internal cleaning and ventilation system. Totally 83 eyes underwent deep anterior lamellar keratoplasty (DALK) using corneal donor tissue preserved with corneal dehydrater, and 60 patients (60 eyes) received DALK by the same surgeon using corneal donor tissue preserved with glycerol were included in the control group. The best corrected visual acuity (BCVA), the thickness and transparency of the corneal buttons were recorded.
RESULTS: After the completion of dehydrating, all the donor corneas maintained a normal shape without any shrinkage or distortion, and the average intraoperative rehydration time was 43.3±12.1s during operation. The mean BCVA of the dehydrater group was 0.30±0.18 at 1wk and 0.32±0.16 at 1mo, which were statistically better than that of the control group (P<0.001). The score of corneal buttons transparency were lower than that of the control group with statistical difference (P<0.001). The thickness of corneal buttons at 1wk and at 1mo in the dehydrater group was significantly better than that of the control group respectively (P<0.001). One week after operation, no corneal button turbidity or edema was observed in both groups.
CONCLUSION: The dehydrater can quickly dehydrate the corneal material in a clean and airtight environment and maintain the original shape of the corneal donor during the dehydrating process. This dehydrater is recommended for long-term high-quality preservation in areas where corneal materials cannot be used within a reasonable time period. 相似文献