Philipp Wolfgang E, Speicher Lilly, Göttinger Wolfgang
Department of Ophthalmology, University of Innsbruck, Austria.
J Cataract Refract Surg. 2003 Apr;29(4):808-20. doi: 10.1016/s0886-3350(02)01611-5.
To describe histopathological and immunohistochemical findings in human corneas after myopic laser in situ keratomileusis (LASIK) followed by iatrogenic keratectasia and after hyperopic LASIK.
Department of Ophthalmology, University of Innsbruck, Innsbruck, Austria.
Clinical, histological, and immunohistochemical investigations were performed of 1 human cornea with iatrogenic keratectasia following myopic LASIK and 1 human cornea with irregular astigmatism and central scar formation after hyperopic LASIK. Corneal buttons were obtained during penetrating keratoplasty in both patients.
Histopathological examination showed thinning of the central stroma with a posterior residual thickness of 190 microm in the patient with iatrogenic keratectasia after myopic LASIK and significant midperipheral thinning in the patient who had hyperopic LASIK. However, this characteristic ablation profile of the stroma after hyperopic LASIK was partially mitigated and compensated by the epithelium, which was significantly thinned in the center and markedly thickened in the midperiphery. Traces of wound healing with minimal scar tissue were present at the flap margin after myopic and hyperopic LASIK. In a few sections of the cornea with keratectasia after myopia LASIK, only a few collagen lamellae were visible crossing between the posterior residual stroma and the superficial flap. Immunohistochemical examination revealed minimally increased staining of dermatan sulfate proteoglycan within the stroma adjacent to the interface of the microkeratome incision. Increased staining of hepatocyte growth factor was found on keratocytes/fibroblasts at the flap margin in both corneas.
The wound-healing response is generally poor after LASIK, which may result in significant weakening of the tensile strength of the cornea after myopic LASIK, probably due to biomechanically ineffective superficial lamella. After LASIK in patients with high hyperopia, compensatory epithelial thickening in the annular midperipheral ablation zone might be partly responsible for regression.
描述近视性准分子原位角膜磨镶术（LASIK）后继发医源性角膜扩张以及远视性LASIK术后人眼角膜的组织病理学和免疫组织化学表现。
奥地利因斯布鲁克大学眼科。
对1例近视性LASIK后继发医源性角膜扩张的人眼角膜以及1例远视性LASIK后出现不规则散光和中央瘢痕形成的人眼角膜进行临床、组织学和免疫组织化学研究。两名患者均在穿透性角膜移植术中获取角膜片。
组织病理学检查显示，近视性LASIK后继发医源性角膜扩张的患者中央基质变薄，后部残余厚度为190微米，远视性LASIK患者中周边明显变薄。然而，远视性LASIK术后基质的这种特征性消融轮廓部分被上皮减轻和代偿，上皮中央明显变薄，中周边明显增厚。近视和远视性LASIK术后瓣边缘有微量伤口愈合痕迹，伴有少量瘢痕组织。在近视性LASIK后继发角膜扩张的角膜的一些切片中，仅可见少数胶原板层在后部残余基质和表层瓣之间交叉。免疫组织化学检查显示，在微型角膜刀切口界面相邻的基质内硫酸皮肤素蛋白聚糖染色略有增加。在两个角膜的瓣边缘的角膜细胞/成纤维细胞上发现肝细胞生长因子染色增加。
LASIK术后伤口愈合反应通常较差可能导致近视性LASIK术后角膜抗张强度显著减弱，这可能是由于生物力学上无效的表层薄片所致。在高度远视患者中，LASIK术后环形中周边消融区的代偿性上皮增厚可能是导致回退的部分原因。
