Nguyen N X, Seitz B, Langenbucher A, Graupner M, Kus M M, Blüthner K, Küchle M, Naumann G O
Augenklinik mit Poliklinik, Universität Erlangen-Nürnberg.
Klin Monbl Augenheilkd. 1999 Sep;215(3):169-74. doi: 10.1055/s-2008-1034694.
The corneal endothelial cell density is essential for the pump function and the transparency of grafts after penetrating keratoplasty (PK). The purpose of this study was to assess corneal endothelial cell density after non-high-risk PK and to check for possible correlations with storage parameters of the donor corneas using two different storage methods.
Endothelial cell density (specular microscope EM 1100, TOMEY, Erlangen) and central corneal thickness (ultrasonic pachymetry SP-2000, TOMEY, Erlangen) were assessed 6 weeks, 3, 6, 9 months and one year postoperatively in 168 non-high-risk PKs. Short-term-preserved donor corneas were used in 89 patients, whereas in 79 patients organ-cultured corneas were used. The donor trephination was performed from the epithelial side using an artificial anterior chamber. The postoperative treatment with topical steroids was standardized. The mean donor post-mortem time was 9.6 +/- 8.0 hours for short-term-preserved and 17.6 +/- 10.5 hours for organ-cultured corneas (p < 0.0001). The storage time was 71 +/- 49 and 380 +/- 167 hours (p < 0.0001), respectively.
Endothelial cell density did not differ significantly between the two storage methods (p > 0.05). At 6 weeks postoperatively, the mean endothelial cell density was 2042 +/- 675 cells/mm2 for short-term-preserved corneas and 1972 +/- 522 cells/mm2 for organ-cultured corneas (p = 0.7). Endothelial cell density did not decrease significantly (p > 0.05) within the observation period of 12 months in both groups (after 12 months: 1868 +/- 957 cells/mm2 and 1638 +/- 643 cells/mm2, respectively). The mean corneal thickness was 542 +/- 50 microns for short-term-preserved and 541 +/- 55 microns for organ-cultured corneas and remainded unchanged during the follow-up of 12 months (542 +/- 42 microns and 521 +/- 43 microns, respectively). Neither the group of short-term-preserved corneas nor organ-cultured corneas showed a significant correlation between endothelial cell density or central cornea thickness with post-mortem time or with storage time of the donor corneas at any postoperative stage (p > 0.1).
During the first year after PK, only a small decrease in endothelial cell density was observed in comparison with the 6-weeks finding. The storage method does not seem to affect the short-term changes of endothelial cell density. Further long-term studies are necessary to assess the clinical relevance of these observations.
角膜内皮细胞密度对于穿透性角膜移植术（PK）后移植物的泵功能和透明度至关重要。本研究的目的是评估非高危PK术后的角膜内皮细胞密度，并使用两种不同的保存方法检查其与供体角膜保存参数之间可能存在的相关性。
对168例非高危PK患者在术后6周、3个月、6个月、9个月和1年时评估内皮细胞密度（使用TOMEY公司的EM 1100镜面显微镜）和中央角膜厚度（使用TOMEY公司的SP - 2000超声角膜测厚仪）。89例患者使用短期保存的供体角膜，79例患者使用器官培养的角膜。使用人工前房从上皮侧进行供体角膜环钻。局部使用类固醇的术后治疗是标准化的。短期保存角膜的供体死后平均时间为9.6±8.0小时，器官培养角膜为17.6±10.5小时（p<0.0001）。保存时间分别为71±49小时和380±167小时（p<0.0001）。
两种保存方法之间的内皮细胞密度无显著差异（p>0.05）。术后6周时，短期保存角膜的平均内皮细胞密度为2042±675个细胞/mm²，器官培养角膜为1972±522个细胞/mm²（p = 0.7）。两组在12个月的观察期内内皮细胞密度均未显著下降（12个月后：分别为1868±957个细胞/mm²和1638±643个细胞/mm²）。短期保存角膜的平均角膜厚度为542±50微米，器官培养角膜为541±55微米，在12个月的随访期间保持不变（分别为542±42微米和521±43微米）。在任何术后阶段，短期保存角膜组和器官培养角膜组的内皮细胞密度或中央角膜厚度与供体角膜的死后时间或保存时间之间均未显示出显著相关性（p>0.1）。
在PK后的第一年，与术后6周时相比，仅观察到内皮细胞密度有小幅下降。保存方法似乎不影响内皮细胞密度的短期变化。需要进一步的长期研究来评估这些观察结果的临床相关性。
