Panhandle Eye Group, Amarillo, Texas.
Am J Ophthalmol. 2013 Dec;156(6):1088-94. doi: 10.1016/j.ajo.2013.06.026. Epub 2013 Sep 25.
To report the visual and anatomic outcomes of a novel technique for the management of anterior corneal scarring using optical coherence tomography (OCT)-guided transepithelial phototherapeutic keratectomy (transepithelial PTK).
Retrospective, consecutive case series.
The charts of 22 patients with anterior corneal scarring associated with irregularities in the Bowman layer who had undergone transepithelial PTK according to a novel protocol were reviewed. The protocol consisted of a preoperative OCT-measured depth-of-treatment calculation, followed by a dual excimer laser treatment profile set to achieve the desired refractive outcome while eliminating or reducing corneal scarring. The primary outcomes were change in best spectacle-corrected visual acuity (BSCVA) and change in corneal topography indices at 4 months after ablation.
BSCVA (in logMAR) improved from a mean of 0.82 (0.61-1.02; 95% confidence interval) preoperatively to a mean of 0.40 postoperatively (0.19-0.61) (P = 0.0070). All patients gained a minimum of 1 line of BSCVA postoperatively. Preoperative and postoperative corneal topographic indices showed significant improvement in corneal cylinder (P = 0.0173) and projected visual acuity (P = 0.0261) but not in the surface asymmetry index (P = 0.0849) or the surface regularity index (P = 0.0543). Postoperative spherical equivalent averaged 0.78 diopters (0.49-1.07) of error from the intended target refractive outcome. No complications were associated with the treatment, and no patients required or desired subsequent treatment with either repeat PTK or with more invasive surgery such as lamellar or penetrating keratoplasty.
OCT-guided transepithelial PTK using a dual ablation excimer laser profile can provide favorable results as well as predictable refractive outcomes in the treatment of corneal scarring associated with Bowman layer irregularities. Future investigations are warranted to further validate the technique reported in this study.
报告使用光学相干断层扫描（OCT）引导的经上皮光性角膜切削术（trans-epithelial PTK）治疗前角膜瘢痕的新型技术的视力和解剖学结果。
回顾性、连续病例系列。
回顾了 22 例前角膜瘢痕伴 Bowman 层不规则患者的病历，这些患者根据一项新方案接受了经上皮 PTK。该方案包括术前 OCT 测量的治疗深度计算，然后进行双准分子激光治疗，以实现所需的屈光效果，同时消除或减少角膜瘢痕。主要结果是在消融后 4 个月时最佳矫正视力（BSCVA）和角膜地形图指数的变化。
BSCVA（以 logMAR 表示）从术前的平均 0.82（0.61-1.02；95%置信区间）提高到术后的平均 0.40（0.19-0.61）（P=0.0070）。所有患者术后均至少提高了一行 BSCVA。术前和术后角膜地形图指数显示角膜柱镜（P=0.0173）和预测视力（P=0.0261）显著改善，但表面不对称指数（P=0.0849）和表面规则指数（P=0.0543）无显著改善。术后等效球镜平均误差为 0.78 屈光度（0.49-1.07），偏离预期目标屈光结果。治疗无并发症，无患者需要或希望再次接受 PTK 或更具侵入性的手术，如板层或穿透性角膜移植术。
使用双消融准分子激光轮廓的 OCT 引导的经上皮 PTK 可在前角膜瘢痕伴 Bowman 层不规则的治疗中提供良好的效果和可预测的屈光结果。需要进一步的研究来进一步验证本研究报告的技术。
