Comparison of cumulative dispersed energy between conventional phacoemulsification and femtosecond laser-assisted cataract surgery with two different lens fragmentation patterns

Hung-Yuan Lin,Shu-Ting Kao,Pi-Jung Lin,Ya-Jung Chuang,Shuan Chen

doi:10.1007/s10103-021-03321-1

Abstract

The purpose of the study is to compare the total ultrasound power used between eyes undergoing different lens fragmentation patterns of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification surgery (CPS). A total of 506 patient eyes underwent preoperative grading of lens opacity using the Lens Opacity Classification System III (LOCSIII). The eyes were divided into two subgroups: subgroup 1 had a LOCSIII grade of 1–3, and subgroup 2 had a LOCSIII grade of 4–6. The eyes underwent FLACS (LenSx) for clear corneal wound, capsulotomy, and lens fragmentation. Either a grid pattern or radial pattern was used for lens fragmentation. The eyes received one of the following three treatments: (1) CPS without femtosecond laser assistant, (2) FLACS with a grid pattern (FGP) lens fragment, or (3) FLACS with a quadrant pattern (FQP) lens fragment. The mean cumulative dispersed energy (CDE) for each subgroup and treatment was evaluated. The mean CDE was lower in the two FLACS groups (1.21±1.91 in FGP and 1.22±1.92 in FQP) than that in the CPG group (2.67±2.84). In subgroup 1, CDE was higher in the CPG group (1.54±1.18) as compared with the FLACS groups (0.16±0.31 in FGP and 0.74±1.17 in FQP; P<0.001). In subgroup 2, CDE was higher in the CPG (6.47±3.46) as compared with the FLACS groups (2.74±2.21 in FGP and 5.34±2.17 in FQP; P<0.001). CDE was lower in the two FLACS groups than that in the CPS group, and CDE was the lowest with FGP in both subgroups 1 and 2.

Highlights

Cataract is the leading cause of blindness worldwide, but it can be resolved by cataract surgery using the phacoemulsification technique, which was developed in Technology, Taichung, Taiwan 3 Department of Ophthalmology, Fujian Medical University, FujianSheng, China 4 Universal Eye Center, Ban-Qiao, Taiwan 5 Universal Eye Center, Long-Tan, Taiwan 6 Universal Eye Center, Taipei, Taiwan1967 [1]
Another study focused on femtosecond laserassisted cataract surgery (FLACS) using different lens fragmentation patterns, including three-plane chop and pie-cut pattern fragmentation; the results showed that the three-plane chop pattern had lower effective phacoemulsification time (EPT), power, and cumulative dispersed energy (CDE) [16]
The mean CDE was significantly lower in the two FLACS groups (1.21±1.91 in FLACS with a grid pattern (FGP) and 1.22±1.92 in the FLACS with a quadrant pattern (FQP) group) than that in the conventional phacoemulsification surgery (CPS) group (2.67±2.84)

Summary

Introduction

ECL was concluded on heat generated by ultrasonic tips and free radicals and fluid turbulence generated during ultrasonic energy delivery, which accumulate with cumulative dispersed energy (CDE) [4,5,6,7]. To reduce those complications, the femtosecond laser was introduced in cataract surgery in 2009 to create corneal incisions, continuous curvilinear capsulorrhexis (CCC), and lens fragmentation [8]. FLACS was demonstrated to create more precise central CCC and a clear wound cut, which decrease refractive surprises such as myopic or hyperopic shift, unwanted surgically induced astigmatism, posterior

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