Comparison Of Time Efficiency Between Conventional Phacoemulsification Cataract Surgery And Femtosecond Laser-Assisted Cataract Surgery Depending On The Nuclear Hardness Of The Cataract And Anterior Chamber Depth Level

While some significant advantages of femtosecond laser-assisted cataract surgery (FLACS), such as precision and reproducibility of capsulorhexis and reduction of cumulative dissipated energy, have been reported, a comparison of time efficiency between conventional phacoemulsification cataract surgery (PCS) and FLACS has not been extensively investigated. Although FLACS has yet to gain popularity due to cost reasons, if FLACS is more time-efficient than PCS, it can compensate for any cost drawbacks of FLACS. This study aims to compare the time efficiency of PCS and FLACS based on nuclear hardness (sclerosis) grade of cataract (NH) and anterior chamber depth (ACD).

Yokohama Tsurumi Chuoh Eye Clinic and Yokosuka Chuoh Eye Clinic, Kanagawa,

Japan

Cataract surgery was performed on 311 eyes of 202 patients. 159 cases were with FLACS and 152 were with PCS. Nuclear hardness was graded with the Emery-Little classification. ACD and axial length (AL) were measured preoperatively. The 311 eyes were divided into 4 groups based on NH and ACD as follows. Group 1: NH> grade 3 and ACD<2.4mm, Group 2: NH> grade 3 and ACD≧2.4 mm, Group 3: NH≦ grade 3 and ACD<2.4mm, Group 4: NH≦grade 3 and ACD≧2.4mm. The following two key parameters were timed: Firstly, the average operation time, and secondly, the degree of deviation of operation time under a microscope. These parameters were timed for the total operation times (laser part + microscope part) and were compared between FLACS and PCS in each group.

No significant difference in NH, ACD and AL between FLACS and PCS was found. The average operation time and the degree of deviation of operation time under the microscope with FLACS were significantly less than with PCS in all groups (P<0.001). Total operation time with FLACS was significantly shorter than with PCS in Group 1 (P<0.001). The opposite was the case in Group 4 (P<0.001). The degree of the deviation of total time with FLACS was significantly less than with PCS only in Group 1 and 3. In cases with harder nuclear (> grade 3) or shallower ACD (<2.4mm), the operation time under the microscope, total operation time, and the degree of deviation with FLACS were significantly reduced when compared with PCS (P<0.001).

Both the average operation time and the degree of deviation of operation time under a microscope with FLACS was significantly more time efficient than with PCS irrespective of NH and ACD level. These results may indicate that FLACS has significant time benefits in settings where the laser part and microscope part are performed simultaneously by two doctors, especially in the eyes with harder nuclear (>grade 3) or shallower ACD (<2.4mm). Considering the results of the total operation time, in the eyes with harder nuclear (>grade 3) or shallower ACD (<2.4mm), the same applies even in settings where these procedures are performed by only one doctor.

The results may indicate that this can compensate for any cost drawbacks of FLACS.