Cornea and External Eye Disease Department, Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore.
Cornea Department, Singapore Eye Research Institute, 20 College Rd, Level 6 Discovery Tower, Singapore.
Indian J Ophthalmol. 2024 Nov 1;72(Suppl 5):S763-S775. doi: 10.4103/IJO.IJO_933_24. Epub 2024 Oct 25.
To study the effect of corneal white-to-white diameter on Pentacam Scheimpflug cornea tomography and Corvis ST corneal visualization Scheimpflug technology parameters in myopic eyes.
In this retrospective cross-sectional study, 190 eyes of 190 Chinese myopic patients (spherical equivalent range: -1.25 D to -11.00 D) assessed for refractive surgery using Pentacam and Corvis ST devices were included. Patients were divided into groups based on corneal diameter: group A <12 mm, and group B ≥12 mm. Age, gender, spherical equivalent, Pentacam variables, and Corvis ST variables were collected. Statistical analysis was performed using IBM SPSS Statistics (Version 28.0).
There were 110 patients in group A and 80 patients in group B, with no statistically significant difference in age, gender, or spherical equivalence. For Pentacam data, group A had significantly higher Belin/Ambrosio Enhanced Ectasia Display (BAD-D) scores than group B (0.88 vs. 0.44) and pachymetric progression index (minimum, average, and maximum), and steeper front keratometric values, whereas group B had larger anterior chamber depth and maximum Ambrosio-relational thickness (ARTmax) (462.54 vs. 503.93). BAD-D indices, pachymetric progression indices, and front keratometric values had negative correlations with corneal diameter, whereas ARTmax and back keratometric values had positive correlations. For Corvis ST data, group A had a significantly higher corneal biomechanical index (CBI) (negatively correlated) while group B had a higher Ambrosio relational thickness to the horizontal profile (ARTh) (473.60 vs. 570.78) (positively correlated).
Corneal diameter influences both Pentacam and Corvis ST parameters, with smaller corneal diameters having a higher BAD-D and a lower ARTmax and ARTh. In addition, this is the first study to report a correlation between posterior surface corneal power and corneal diameter. As refractive surgery evaluation relies on these parameters, taking corneal diameter into account would improve both sensitivity and specificity in pre-refractive surgery screening for ectasia/keratoconus.
研究角膜白对白直径对 Pentacam 眼前节断层扫描仪和 Corvis ST 角膜可视化 Scheimpflug 技术在近视眼中参数的影响。
本回顾性横断面研究纳入了 190 名（等效球镜范围：-1.25D 至-11.00D）接受屈光手术的中国近视患者的 190 只眼。根据角膜直径将患者分为两组：A 组<12mm，B 组≥12mm。收集年龄、性别、等效球镜、Pentacam 变量和 Corvis ST 变量。采用 IBM SPSS Statistics（版本 28.0）进行统计学分析。
A 组 110 例，B 组 80 例，两组患者年龄、性别、等效球镜无统计学差异。对于 Pentacam 数据，A 组 Belin/Ambrosio 增强扩张症显示（BAD-D）评分显著高于 B 组（0.88 比 0.44）和角膜厚度进展指数（最小、平均和最大），前角膜曲率值也更大，而 B 组前房深度和最大 Ambrosio 相关性厚度（ARTmax）更大（462.54 比 503.93）。BAD-D 指数、角膜厚度进展指数和前角膜曲率值与角膜直径呈负相关，而 ARTmax 和后角膜曲率值与角膜直径呈正相关。对于 Corvis ST 数据，A 组角膜生物力学指数（CBI）较低（呈负相关），而 B 组水平剖面 Ambrosio 相关性厚度（ARTh）较大（473.60 比 570.78）（呈正相关）。
角膜直径影响 Pentacam 和 Corvis ST 参数，较小的角膜直径具有较高的 BAD-D 和较低的 ARTmax 和 ARTh。此外，这是第一项报道后表面角膜曲率与角膜直径之间相关性的研究。由于屈光手术评估依赖于这些参数，因此在屈光手术前的筛查中考虑角膜直径将提高对扩张症/圆锥角膜的敏感性和特异性。
