Singapore Eye Bank, Singapore, Singapore.
Singapore National Eye Centre, Singapore, Singapore.
PLoS One. 2021 Dec 2;16(12):e0260523. doi: 10.1371/journal.pone.0260523. eCollection 2021.
To compare the utilization rate and usage patterns of pseudophakic and phakic donor corneas recovered by the Singapore Eye Bank.
Records of local donor corneas recovered by the Singapore Eye Bank from 2012 to 2017 were examined. Corneas that were deemed suitable for clinical use were stratified into phakic and pseudophakic groups. We examined the basic demographic pattern of both groups and the initial type of surgery/ies that the corneas were suitable for based on tissue parameters such as time from harvesting, stromal clarity, the clear central corneal area, the presence of Descemet's membrane tears or defects, and endothelial cell density and quality. We also identified the types of corneal grafts that the corneas were eventually used for; Penetrating Keratoplasty (PK), Anterior Lamellar Keratoplasty (ALK), Endothelial Keratoplasty (EK). Finally, the overall utilization rates for each group were determined.
A total of 986 corneas deemed suitable for transplant were analyzed, 908 (92%) were phakic and 78 were pseudophakic (8%). The average age of pseudophakic donor corneas was (65 ± 8 yrs. old) and there was a slight male preponderance for both groups (55%). Age adjusted analysis of pseudophakic corneas showed the endothelial cell density (ECD) (mean: 2327 ± 47.1 cells/mm2) and clear area (mean: 7.0 ± 0.7 mm) were lesser than phakic corneas. The percentage of pseudophakic corneas that were of EK standard (ECD >2500 cells/mm2) were lower compared to phakic corneas (37% and 77% respectively, p < 0.001). There was significant correlation between previous cataract surgery and the endothelial cell count of the donor corneas (p < 0.001), and regression analysis also showed a strong association of ECD with cataract surgery in reference to non-cataract surgery (-478.8 (95% CI-576.9 to -380.7). The overall utilization rate for pseudophakic corneas was 58% compared to that of phakic corneas at 83%. The most common reason for pseudophakic corneas not to be utilized was due to the presence of Descemet's membrane (DM) tears or defects under the main or side port incision created during phacoemulsification (30%). Phakic corneas were used primarily for optical grafts 84% (mainly EK) while pseudophakic corneas were used mostly for therapeutic/tectonic grafts 47% (mainly ALK or patch grafts).
Compared to phakic donor corneas, pseudophakic corneas generally have lower overall tissue quality leading to lower uptake by surgeons and lower utilization rates. Eye banks must continuously refine their donor acceptance criteria and engage surgeons to optimize utilization of each recovered tissue.
比较新加坡眼库回收的后房型和前房型供体角膜的利用率和使用模式。
检查 2012 年至 2017 年期间由新加坡眼库回收的本地供体角膜的记录。将被认为适合临床使用的角膜分层为后房型和前房型组。我们检查了两组的基本人口统计学模式，以及根据组织参数（如从收获到现在的时间、基质清晰度、中央透明角膜区域、是否存在 Descemet 膜撕裂或缺陷以及内皮细胞密度和质量）适合的初始手术类型/种。我们还确定了角膜最终用于的移植类型；穿透性角膜移植术（PK）、前板层角膜移植术（ALK）、内皮角膜移植术（EK）。最后，确定了每组的总体利用率。
共分析了 986 只适合移植的角膜，其中 908 只（92%）为后房型，78 只为前房型（8%）。前房型供体角膜的平均年龄为（65±8 岁），两组均有轻微的男性优势（55%）。对前房型供体角膜进行年龄调整分析显示，内皮细胞密度（ECD）（平均值：2327±47.1 个细胞/mm2）和透明区（平均值：7.0±0.7mm）小于后房型。符合 EK 标准（ECD>2500 个细胞/mm2）的前房型供体角膜比例低于后房型（分别为 37%和 77%，p<0.001）。白内障手术与供体角膜内皮细胞计数之间存在显著相关性（p<0.001），回归分析还显示，ECD 与白内障手术与非白内障手术之间存在很强的关联（-478.8（95%CI-576.9 至-380.7）。前房型供体角膜的总体利用率为 58%，而后房型为 83%。前房型供体角膜未被利用的最常见原因是在白内障超声乳化术中创建的主或侧端口下存在德氏膜（DM）撕裂或缺陷（30%）。后房型供体角膜主要用于光学移植 84%（主要为 EK），而前房型供体角膜主要用于治疗/结构性移植 47%（主要为 ALK 或补片移植）。
与后房型供体角膜相比，前房型供体角膜的总体组织质量通常较低，导致外科医生接受率较低，利用率较低。眼库必须不断完善供体接受标准，并与外科医生合作，以优化每个回收组织的利用率。
