Femtosecond Laser–Assisted Cataract Surgery Versus Conventional Phacoemulsification Surgery: Effective Phaco Time and Visual Outcomes
Purpose
To report effective phacoemulsification time (EPT) and unaided visual results after femtosecond laser-assisted cataract surgery (FLACS, F) and compare with conventional phacoemulsification surgery (C) in a single surgeon series.
Methods
A prospective audit of EPT and visual outcome at 6 weeks comparing FLACs (capsulotomy, 2, 3 or 4 radial nuclear cuts) to controls (coaxial phacoemulsification) by the same surgeon, using the direct phaco-chop technique. Age, preoperative cylinder and nuclear density spread were compared (chi sq test).Outcome measures: Unaided and best corrected visual acuity (UAVA, BCVA), mean absolute error (MAE), manifest refraction spherical equivalent (MRSE) (Mann-Whitney U, p<0.05). Median and mean EPT was computed for 3 nuclear density groups (LOCS III grade: NS0-2, NS3-4 and NS5-6) and compared. Poor visual prognosis eyes were excluded.
Results
One-hundred forty-three FLACS (Victus; 5-mm capsulotomy; segments: 4 (NS≤2), 6 (NS3-4) or 8 (NS5-6) ) and 118 controls were analyzed. No difference in age, preoperative cylinder and nuclear density spread between groups (Mann-Whitney U test). Significant correlation between EPT and nuclear density but mean EPT between groups was insignificant (F= 3.45 ±4.3 s, C= 4.18± 3.95 s; p>0.05). FLACS cases achieved higher % UVA 20/25 or better at 6 weeks (F=64.8%, C=48.0%; p<0.05). No difference in % BCVA 20/25 (F=79.4%, C=79.9%) or MAE (F=0.31±0.26 D, C=0.37±0.36D, p=0.16). FLACs with target SE<0.5D had lower MRSE (F=-0.24 ± 0.39D, C= -0.41±0.51D;p=0.007).
Conclusion
There was no significant difference in EPT for FLACS cases which received laser capsulotomy and nuclear fragmentation with radial cuts only, compared to conventional phacoemulsification with direct phaco chop technique, for similar nuclear densities. For cases with target SE<0.5D, FLACS achieved higher % UVA of 20/25 or better, with smaller MRSE, supporting the notion that FLACS provides incrementally more precise refractive outcomes.