PURPOSE To assess intraoperative stromal topography measurements using swept-source optical coherence tomography (OCT)-based topography/tomography after epithelial removal and to analyze the epithelial contribution to the corneal topography and optics. METHODS This was a prospective series of 22 eyes of 19 patients referred to receive phototherapeutic keratotomy (PTK) for treatment of recurrent corneal erosion and a control group of 22 virgin eyes. Swept-source OCT corneal topography/tomography was obtained immediately before and immediately after mechanical deepithelialization before PTK. Epithelial thickness maps were obtained before the surgery using spectral-domain OCT in the control group and as a reference in the group with anterior basement membrane dystrophy. Topographic and optical characteristics, including the curvature, astigmatism, asphericity, and higher order aberrations of the cornea before and after deepithelialization were compared, and their differences correlated with the measurements derived from the epithelial thickness maps. RESULTS Stromal topography measurements after deepithelialization were easily obtained and showed excellent repeatability. Assessment of corneal edema induced by deepithelialization revealed that it did not significantly affect the measured parameters. The stromal surface was steeper by 1.28 diopters, had higher with-the-rule astigmatism by 0.41 diopters, was more prolate, and had more higher order aberrations compared to the intact epithelialized corneal surface. These differences correlated well with the parameters derived from epithelial thickness maps. CONCLUSIONS Measurement of stromal topography using swept-source OCT immediately after mechanical deepithelialization may be a viable method in therapeutic refractive surgery, where stromal topography-guided ablation is needed. A significant epithelial contribution to anterior corneal topography and optics was confirmed. [J Refract Surg. 2021;37(7):484-492.].

中文翻译：

---

用于测量和分析上皮去除后基质表面的术中扫描源 OCT 角膜地形图。

目的：在去除上皮后使用基于扫频源光学相干断层扫描 (OCT) 的地形/断层扫描评估术中基质地形测量，并分析上皮对角膜地形和光学的贡献。方法 这是一个前瞻性系列，包括 19 名接受光疗角膜切开术 (PTK) 治疗复发性角膜糜烂的患者，共 22 只眼，对照组 22 只处女眼。扫描源 OCT 角膜地形图/断层扫描是在 PTK 之前和机械去上皮化之后立即获得的。对照组在手术前使用谱域OCT获得上皮厚度图，并作为前基底膜营养不良组的参考。地形和光学特性，包括曲率、散光、比较了去上皮化前后角膜的非球面性和高阶像差，它们的差异与从上皮厚度图得出的测量值相关。结果 去上皮化后的基质形貌测量很容易获得，并显示出极好的可重复性。对去上皮化诱导的角膜水肿的评估表明，它对测量参数没有显着影响。与完整的上皮角膜表面相比，基质表面更陡峭 1.28 屈光度，具有更高的规则散光 0.41 屈光度，更扁长，并且具有更多高阶像差。这些差异与源自上皮厚度图的参数很好地相关。结论 机械去上皮后立即使用扫频源 OCT 测量基质地形可能是治疗性屈光手术中的一种可行方法，其中需要基质地形引导的消融。证实了对前角膜地形图和光学的显着上皮贡献。[J 屈光手术。2021;37(7):484-492.]。