【摘要】 目的观察PRK术后兔角膜上皮层的厚度及细胞增殖活性变化并探讨其发生的机制。方法21只兔按右眼-5.0D、左眼-15.0D行PRK。术后第1、3天,1、2周,1、3、6个月分别取角膜,光镜下测定角膜上皮层厚度,免疫组化染色观察角膜上皮增殖细胞核抗原(PCNA)表达。结果-5.0D组及-15.0D组术后2周以后切削区上皮层厚度都显著超过正常,至术后6个月仍未恢复正常,-15.0D组尤为明显;两组术后切削区新生上皮PCNA阳性率均明显增高,-5.0D组至术后1个月、-15.0D组至术后3个月恢复正常。结论PRK术后可以发生持续性的角膜上皮过度增生,深度切削组尤为明显。上皮细胞增殖活性的过度增强可能是导致PRK术后角膜上皮过度增生的主要原因。更多还原

【Abstract】 Objective To investigate the proliferative changes in corneal epithelium after photorefractive keratectomy (PRK). Methods PRK was performed on both eyes of 21 New Zealand white rabbits. The attempted corrections were -5.0 diopters for the right eye and -15.0 diopters for the left. The eyes were enucleated respectively at 1,3 days, 1 and 2 weeks,and 1,3 and 6 months after surgery.The thickness of epithelium was measured under light microscope. The positive cell rate of proliferating cell nuclear antigen (PCNA) in the healing epithelium was also examined. Results The epithelial thickness increased from 2 weeks postoperativey tile 6 months, especially for the left eye. The PCNA positive cells in the regenerating basal cell layer became more than that of controls from the 3rd day, and didn′t return to normal until 1 month after surgery for the right eye and 3 months for the left. Conclusions The corneal epithelium shows proliferating disturbance for several weeks after PRK, especially in the deeper ablated corneas. The proliferating activity enhancement may be the most important reason for the epithelium hyperplasia after PRK.更多还原