Clínica Oftalmológica Malbran, Buenos Aires, Argentina.
Fundación Oftalmológica Argentina Jorge Malbran, Buenos Aires, Argentina.
Cornea. 2019 Nov;38(11):1377-1381. doi: 10.1097/ICO.0000000000002121.
To describe outcomes of customized peripheral anterior lamellar keratoplasty (PALK) for late ectasia of the donor-recipient junction after penetrating keratoplasty (PK) for keratoconus.
This was a single-center, retrospective review of 33 eyes (28 patients) that developed ectasia restricted to the graft-host junction; 17 eyes underwent PALK using lamellar resections of 8- to 11-mm width starting at the external margin of the previous PK and suturing a same-size donor graft (annular or segmental). Five eyes were excluded from analysis because of postoperative complications unrelated to the technique.
The average time between PK and diagnosis of secondary ectasia was 28 years (range 9-49 years). Slit-lamp examination showed localized thinning and elongation of the scar at the graft-host junction with well-defined biomicroscopic limits. Preoperatively, the mean keratometric measures were K1: 44.8 ± 4.8 D and K2: 54.1 ± 4.8 D and postoperatively K1: 47.5 ± 3.5 D and K2: 50.8 ± 2.6 D. The mean improvement in corrected visual acuity was 10 lines, and mean cylinder improved from 9.3 ± 2.1 D to 3.3 ± 1.4 D. All cases showed anatomical and refractive improvement.
With long-term follow-up, late post-PK ectasia becomes an increasing problem. PALK can be a successful surgical option to reinforce the ectatic area while preserving a functional clear PK. By adding donor corneal tissue, PALK restores the ectatic area, improves visual acuity, keratometric values, and astigmatism, and preserves the functional graft while avoiding the higher risks of a larger diameter PK.
描述用于治疗圆锥角膜穿透性角膜移植术后供受区交界处晚期扩张的定制周边前板层角膜移植术(PALK)的结果。
这是一项单中心回顾性研究,共纳入 33 只眼(28 例患者),这些眼的病变仅局限于移植物-宿主交界处,其中 17 只眼接受了 PALK 治疗,从先前 PK 的外部边缘开始进行 8-11mm 宽的板层切除,并缝合相同大小的供体移植物(环形或节段性)。由于与该技术无关的术后并发症,有 5 只眼被排除在分析之外。
PK 与继发性扩张的诊断之间的平均时间为 28 年(范围 9-49 年)。裂隙灯检查显示在移植物-宿主交界处有局灶性变薄和瘢痕拉长,具有明确的生物显微镜界限。术前平均角膜曲率计测量值为 K1:44.8±4.8D 和 K2:54.1±4.8D,术后为 K1:47.5±3.5D 和 K2:50.8±2.6D。矫正视力平均提高 10 行,平均柱镜度从 9.3±2.1D 改善至 3.3±1.4D。所有病例均显示解剖学和屈光改善。
随着长期随访,PK 后晚期扩张成为一个日益严重的问题。PALK 可以作为一种成功的手术选择,在加强扩张区域的同时保留功能清晰的 PK。通过添加供体角膜组织,PALK 可以恢复扩张区域,提高视力、角膜曲率值和散光,并保留功能移植物,同时避免更大直径 PK 的更高风险。