背景:角膜上皮重塑对角膜前表面变化的反应(圆锥角膜,角膜屈光手术)在文献中有很好的记载。然而,几种情况可能会诱导上皮的不同行为,其中上皮增厚的局灶性区域引起不规则散光。该病例报告介绍了由病因不明的上皮增生引起的不规则散光的非常罕见的病例。仅通过机械去除上皮来治疗。
方法:一名29岁的女性接受了植入式晶状体植入以矫正近视。患者提供书面知情同意书。手术在两只眼睛里都很顺利。20个月后,她抱怨左眼视力下降(未矫正的远距视力(UCDVA)为20/30;矫正的远距视力为20/20,为1.00-2.25×170)。角膜地形图显示左眼鼻陡变。虽然角膜厚度图正常,上皮厚度图显示,左眼的局部鼻腔上皮增生区域与曲率最陡的区域相匹配。裂隙灯检查显示角膜完全透明,无异常迹象。患者病史不明显,1例病因不明的上皮增生,没有活动性炎症,被考虑。决定在应用稀释的酒精后进行角膜上皮的机械去除。手术后一个月,上皮化角膜的地形图显示规则的领结图案,UCDVA改善至20/20。21个月后未发现上皮增生复发。
结论:局灶性上皮增生可诱发不规则散光。上皮厚度标测是评估不规则地形病例的非常有用的技术工具。上皮去上皮化作为一种孤立的程序可能对成功治疗这些病例有用。需要进一步的研究来了解触发局灶性上皮增生自发发展的机制。
BACKGROUND: Corneal epithelium remodeling in response to changes in the anterior corneal surface (keratoconus, corneal refractive surgery) is well-documented in the literature. However, several conditions may induce a different behavior of the epithelium, in which focal areas of epithelial thickening induce irregular astigmatism. This case report presents a highly unusual case of irregular astigmatism induced by an epithelial hyperplasia of unknown etiology, which was treated by the mechanical removal of only the epithelium.
METHODS: A 29-year-old woman underwent implantable collamer lens implantation to correct myopia. The patient provided written informed consent. The procedure was uneventful in both eyes. Twenty months later, she complained of decreased visual acuity in the left eye (uncorrected distance visual acuity (UCDVA) was 20/30; corrected distance visual acuity was 20/20 with + 1.00 -2.25 × 170). Corneal topography revealed a nasal steepening in the left eye. Although the corneal thickness map was normal, epithelial thickness mapping revealed a localized nasal area of epithelial hyperplasia in the left eye that matched the area of steepest curvature. Slit lamp examination showed a total clear cornea with no signs of abnormality. The patient´s medical history was unremarkable and a case of epithelial hyperplasia of unknown etiology, without active inflammation, was considered. The decision was made to perform a mechanical removal of the corneal epithelium after application of diluted alcohol. One month after the procedure, the topography of the epithelized cornea showed a regular bow tie pattern and UCDVA improved to 20/20. No recurrence of the epithelial hyperplasia was detected after twenty-one months.
CONCLUSIONS: Focal epithelial hyperplasia may induce irregular astigmatism. Epithelial thickness mapping is a very helpful technological tool to assess cases with irregular topography. De-epithelization as an isolated procedure may be useful for the successful management of these cases. Further research is required to understand the mechanism that triggers the spontaneous development of a focal epithelial hyperplasia.