Ing J J, Ing H H, Nelson L R, Hodge D O, Bourne W M
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Ophthalmology. 1998 Oct;105(10):1855-65. doi: 10.1016/S0161-6420(98)91030-2.
To investigate the changes in central corneal endothelial cells and corneal thickness in transplanted corneas from 5 to 10 years after grafting. This study also aimed to investigate the development of glaucoma, graft rejection, and graft failure during the first 10 postoperative years.
DESIGN/PARTICIPANTS: Longitudinal cohort study of 500 consecutive penetrating keratoplasties by 1 surgeon. Patients were asked to return for follow-up examinations at 2 months and at 1, 3, 5, and 10 years after grafting. The authors excluded eyes regrafted during the study and the fellow eyes of bilateral cases, leaving 394 grafts in 394 patients for analysis.
Penetrating keratoplasty was performed.
Using specular microscopy, the authors measured endothelial cell density, coefficient of variation of cell area, percentage of hexagonal cells, and corneal thickness. The authors performed clinical examinations to determine graft rejection or failure and the development of glaucoma.
By 10 years postkeratoplasty, 80 of the 394 patients had died and 68 grafts had failed. Of the remaining 246 patients, 119 (48%) returned for their 10-year examinations. For the 72 patients who returned for all of the scheduled postoperative visits and had no rejection episodes, reoperations, or failure, endothelial cell loss from preoperative donor levels at 10 years was 67 +/- 18% (mean +/- standard deviation), endothelial cell density was 958 +/- 471 cells/mm2, coefficient of variation was 0.32 +/- 0.11, hexagonal cells were 56 +/- 12%, and corneal thickness was 0.58 +/- 0.05 mm. The 5- to 10-year changes for all these values were significant (P < or = 0.004). The mean rate of late endothelial cell loss from 5 to 10 years postkeratoplasty was 4.2% per year. Eyes that were aphakic after grafting had the lowest endothelial cell loss (57 +/- 24%) and the lowest interval cell loss from 5 to 10 years postkeratoplasty (4 +/- 19%). Eyes that were phakic had the highest endothelial cell loss (73 +/- 8%) and 5- to 10-year-interval cell loss (17 +/- 31%). Eyes with posterior chamber lenses had a greater endothelial cell loss (71 +/- 9%) than did eyes with anterior chamber lenses (51 +/- 25%, P = 0.03). The 10-year cumulative risk of glaucoma, rejection, or failure was 21%, 21%, and 22%, respectively. Late endothelial failure became the major cause for graft failure, accounting for 9 of the 11 failures after 5 postoperative years.
From 5 to 10 years after penetrating keratoplasty, the annual rate of endothelial cell loss was seven times the normal rate. The endothelial cell loss, pleomorphism, polymegethism, and corneal thickness increased significantly during this time, indicating continued endothelial instability and dysfunction, resulting in an increasing rate of late endothelial failure.
研究移植角膜术后5至10年中央角膜内皮细胞及角膜厚度的变化。本研究还旨在调查术后头10年内青光眼、移植排斥反应及移植失败的发生情况。
设计/研究对象：对一位外科医生连续实施的500例穿透性角膜移植术进行纵向队列研究。患者需在术后2个月、1年、3年、5年及10年返回接受随访检查。作者排除了研究期间再次移植的眼及双侧病例的对侧眼，最终纳入394例患者的394只移植眼进行分析。
实施穿透性角膜移植术。
作者使用镜面显微镜测量内皮细胞密度、细胞面积变异系数、六角形细胞百分比及角膜厚度。进行临床检查以确定移植排斥反应或失败情况以及青光眼的发生情况。
角膜移植术后10年，394例患者中有80例死亡，68只移植眼失败。在其余246例患者中，119例（48%）返回接受10年检查。对于72例按计划完成所有术后随访且无排斥反应、再次手术或移植失败的患者，术后10年内皮细胞较术前供体水平损失67±18%（均值±标准差），内皮细胞密度为958±471个/mm²，变异系数为0.32±0.11，六角形细胞为56±12%，角膜厚度为0.58±0.05mm。所有这些值在5至10年的变化均具有显著性（P≤（或）=0.004）。角膜移植术后5至10年晚期内皮细胞损失的平均年率为4.2%。移植术后无晶状体眼的内皮细胞损失最低（57±24%），角膜移植术后5至10年的细胞损失间隔也最低（4±19%）。有晶状体眼的内皮细胞损失最高（73±8%），5至10年的细胞损失间隔为（17±31%）。植入后房型人工晶状体的眼比植入前房型人工晶状体的眼有更大的内皮细胞损失（71±9%比51±25%，P = 0.03）。青光眼、排斥反应或移植失败的10年累积风险分别为21%、21%和22%。晚期内皮功能衰竭成为移植失败的主要原因，占术后5年之后11例失败中的9例。
穿透性角膜移植术后5至10年，内皮细胞年损失率是正常率的7倍。在此期间，内皮细胞损失、多形性、大小不均一性及角膜厚度显著增加，表明内皮持续不稳定及功能障碍，导致晚期内皮功能衰竭发生率上升。
