AIM: To evaluate safety, efficacy, visual quality, and patient satisfaction after optimized monovision Q-value-customized femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia, astigmatism, and presbyopia. METHODS: This prospective study enrolled patients suffering myopia, astigmatism, and presbyopia. At 1 y post operation, uncorrected distance, intermediate and near visual acuity(UDVA, UIVA, UNVA), refraction, corneal higher order aberrations(HOAs), Q value, objective visual quality, and near stereoacuity were evaluated. The impact of surgery on patients' living quality and their satisfaction were evaluated based on National Eye Institute Refractive Error Quality of Life Instrument(NEI RQL)scores at 1-year follow-up.RESULTS:The study enrolled 36 patients(72 eyes)including 12 males(33%)and 24 females(67%)with an average age of 46.03±3.60(range 40-53)y. One year postoperatively, 97% of patients achieved binocular UDVA of 1.0 or better, 89% achieved UIVA of 0.63 or better, and 97% achieved UNVA of 1.0 or better. The spherical equivalent refraction(SE)in dominant eye within ±1.00 D was 100%. SE in non-dominant eyes was uncorrected compared with the preoperative target correction, with a mean difference of -0.27±0.34 D before and after surgery(P<0.001). while in the non-dominant eyes, the anterior corneal Q-value within the 5 mm zone increased negatively compared with the preoperative value(-0.33±0.24 vs -0.21±0.09, P<0.001). In the non-dominant eye, spherical aberration and longitudinal spherical aberration were lower than preoperative values(both P<0.001). Besides, there were no significant changes in objective scatter index(OSI), modulation transfer function cutoff frequency(MTF cut off)and Strehl ratio(SR)in both dominant and non-dominant eyes(all P>0.05), and the near stereoacuity was better after surgery(P=0.007). Additionally, the patient satisfaction rate with the surgery was 94%, the satisfaction rates for UDVA and UNVA were both 98%. The 11% of patients required to wear low-diopter glasses when driving at night.CONCLUSION:Optimized monovision Q-value-customised FS-LASIK is a safe and effective procedure for correcting myopia, astigmatism, and presbyopia. It provides favorable subjective and objective visual quality and high patient satisfaction. The under correction in non-dominant eyes is observed, indicating the further optimization of nomogram is needed.

AIM: To observe the clinical outcomes of Phorcides analytic engine-assisted topography-guided personalized laser assisted in situ keratomileusis(LASIK)for the treatment of myopia and astigmatism in virgin eyes with the refractive astigmatism significantly deviating from corneal topography.METHODS: Retrospective clinical study. A total of 32 cases(42 eyes)with myopia and astigmatism that received corneal topography-guided personalized LASIK in the Ophthalmology Refractive Surgery Center of the First Affiliated Hospital of Xi'an Jiaotong University from December 2019 to March 2021 were selected. The uncorrected distance visual acuity(UDVA), best corrected distance visual acuity(CDVA), refractive state and aberrations before and at 6 mo after surgery were recorded.RESULTS: There were 15 males and 17 females, with an age of 23.00(18.00, 29.25)years old; preoperative sphere was -5.75(-6.25, -4.00)D, and cylinder was -0.75(-1.38, -0.25)D. At 6 mo postoperatively, the UDVA exceeded the preoperative CDVA in 19 eyes(45%). The spherical equivalent(SEQ)of all eyes(100%)was -0.50 to +0.50 D at 6 mo postoperatively, and the postoperative SEQ of 23 eyes(55%)was -0.13 to +0.13 D. There were 33 eyes(79%)had a postoperative astigmatism ≤ 0.25 D, the target-induced astigmatism(TIA)was 0.94±0.96 D, and the surgically induced astigmatism(SIA)was 0.94±0.86 D, with no statistical significance between TIA and SIA(P>0.05). The astigmatism axial deviation ranged from -5° to +5° in 33 eyes(79%)at 6 mo postoperatively. Compared to pre-operation, the total higher-order aberrations and spherical aberrations within the central 6 mm diameter of the anterior corneal surface increased at 6 mo postoperatively(Z=-3.778, P<0.001; Z=-4.929, P<0.001); the postoperative coma aberrations had no change(Z=-1.763, P=0.078); the postoperative trefoil aberrations decreased(Z=-2.490, P=0.013). Compared to pre-operation, the Strehl ratio of the anterior corneal surface increased significantly at 6 mo after surgeries(t=-5.401, P=0.013).CONCLUSION: Using the Phorcides analytic engine to assist topography-guided personalized LASIK for the treatment of myopia and astigmatism in virgin eyes with the refractive astigmatism significantly deviating from topography-measured astigmatism can achieve good therapeutic effects. Postoperative UDVA exceeded preoperative CDVA in nearly half of the eyes, and the quality of postoperative corneal imaging was improved.