Agreement Between Predicted and Actual Measured Ablation Depth After FS-LASIK Using Different Rotating Scheimpflug Cameras and OCT

Frontiers in Medicine

article

Meimin Lin¹  Giacomo Savini²  Qinmei Wang¹  Ayong Yu¹  Sisi Chen¹  Hao Chen¹  Ziqian Wang¹  Kunke Li³  Yiran Wang¹  Xin Li¹  Lan Du¹ 

[1] School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University;IRCCS G.B. Bietti Foundation;Shenzhen Eye Hospital, Shenzhen Key Ophthalmic Laboratory, Jinan University

关键词: ablation depth;    laser in situ keratomileusis;    femtosecond laser;    difference;    agreement;   

DOI  :  10.3389/fmed.2022.907334

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

Purpose To compare the predicted ablation depth (AD) with the postoperatively measured corneal ablation depth (postop-AD) at central, paracentral, and midperipheral locations using two rotating Scheimpflug analyzers and a Fourier-domain optical coherence tomographer in eyes that underwent femtosecond laser-assisted LASIK (FS-LASIK). Methods The values of corneal thickness were measured preoperatively and postoperatively at one and three months. The difference between preoperative and postoperative was defined as postop-AD. Measurements were performed at the corneal vertex and mid-peripheral area. The mid-peripheral corneal thickness was measured at the superior, inferior, nasal, and temporal locations at a distance of 1.0 or 2.5 mm from the corneal vertex. The predicted AD was calculated by ORK-CAM software (Schwind eye tech-solutions GmbH, Kleinostheim, Germany), and the difference between the predicted AD and postop-AD was defined as Δ-AD. Paired t- test analysis was employed to evaluate the differences, agreement was assessed by the Bland-Altman method. Results Forty-two eyes of 42 patients were investigated. At one month, the predicted AD in the central and paracentral areas was underestimated by the Pentacam HR (Oculus, Wetzlar, Germany), Sirius (Costruzione Strumenti Oftalmici, Florence, Italy) and RTVue OCT (Optovue Inc., Freemont, CA, United States), whereas Δ-AD was negative as established by all devices and predominantly statistically significant. The Δ-AD values approximated zero at three months. The mean difference of Δ-AD at three months at the corneal vertex was 0.67 ± 9.39 mm, −7.92 ± 9.05 mm and −1.36 ± 8.31 mm, respectively. The mid-peripheral measurements had positive values at one month and even more highly positive at three months (with statistically significant differences in most of the cases). The agreement between the predicted and postop-AD was moderate with all devices, but slightly better with RTVue. Conclusion The predicted AD seems to be underestimated in the central and paracentral corneal area and overestimated in the mid-periphery. Translational Relevance The study could help to partly explain and prevent the refractive errors after FS-LASIK.

【 授权许可】

CC BY