State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Qingdao Eye Hospital of Shandong First Medical University, Eye Institute of Shandong First Medical University, Qingdao, 266071, Shandong Province, China.
Graefes Arch Clin Exp Ophthalmol. 2023 Mar;261(3):857-865. doi: 10.1007/s00417-022-05814-3. Epub 2022 Sep 23.
This study aimed to investigate the stability of posterior corneal surface 2 years after transepithelial photorefractive keratectomy (TPRK) in patients with a residual stromal thickness less than 350 μm.
In total, 408 eyes of 212 patients (160 women, 52 men) who underwent TPRK were enrolled in this retrospective study. All surgeries were performed in the Amaris 750S excimer laser platform with smart pulse technology. The posterior corneal elevation, anterior chamber depth, Q value, and curvature were measured using Pentacam preoperatively and postoperatively. All patients were followed up for 2 years. The relationship between percent tissue altered (PTA), age, and changes in posterior corneal surface was analyzed.
The mean preoperative spherical equivalent was - 6.80 ± 1.18 D (range: - 9.00 to - 2.63 D). The mean residual stromal thickness was 336.46 ± 7.25 μm (range: 310-348 μm). The mean PTA was 30.93 ± 2.03% (range: 24.29-35.28%). At 2 years after surgery, the elevation of six points in the central area decreased by 1.91 ± 2.97 μm, 2.98 ± 3.23 μm, 1.17 ± 3.85 μm, 1.70 ± 2.88 μm, 1.36 ± 3.19 μm, and 1.65 ± 3.18 μm, compared with the preoperative value (P < 0.05). The elevation of three points in the peripheral area increased by 1.87 ± 6.34 μm, 0.68 ± 6.00 μm, and 0.95 ± 5.50 μm (P < 0.05). There was no significant linear relationship between PTA, age, and changes in posterior corneal surface, anterior chamber depth, and K2 (all P > 0.05).
Within 2 years after TPRK, the posterior corneal surface remained stable in patients with a residual stromal thickness between 310 and 350 μm. There was no sign of iatrogenic ectasia during the follow-up period.
本研究旨在探讨残余基质厚度小于 350μm 的患者行经上皮准分子激光角膜切削术（TPRK）后 2 年的后角膜表面稳定性。
本回顾性研究共纳入 212 例（160 名女性，52 名男性）408 只眼行 TPRK 的患者。所有手术均在阿玛仕 750S 准分子激光平台上采用智能脉冲技术进行。术前和术后使用 Pentacam 测量后角膜隆起、前房深度、Q 值和曲率。所有患者均随访 2 年。分析了百分比组织改变（PTA）、年龄与后角膜表面变化之间的关系。
术前平均等效球镜度数为-6.80±1.18D（范围：-9.00 至-2.63D）。平均残余基质厚度为 336.46±7.25μm（范围：310-348μm）。平均 PTA 为 30.93±2.03%（范围：24.29-35.28%）。术后 2 年，中央区 6 个点的隆起下降了 1.91±2.97μm、2.98±3.23μm、1.17±3.85μm、1.70±2.88μm、1.36±3.19μm 和 1.65±3.18μm，与术前值相比差异均有统计学意义（P<0.05）。周边区 3 个点的隆起分别增加了 1.87±6.34μm、0.68±6.00μm 和 0.95±5.50μm（P<0.05）。PTA、年龄与后角膜表面、前房深度和 K2 的变化之间无显著线性关系（均 P>0.05）。
在 TPRK 术后 2 年内，残余基质厚度在 310-350μm 之间的患者后角膜表面保持稳定，随访期间无医源性扩张迹象。
