AIM: To compare the visual quality in patients with low-to-moderate myopia after 0.05 D interval spherical lens optometry-guided small-incision lenticule extraction(SMILE)and conventional 0.25 D interval spherical lens optometry-guided SMILE.

METHODS: Retrospective study. A total of 400 cases(400 eyes)with low-to-moderate myopia that underwent SMILE in the ophthalmology department of 989th Hospital of Joint Logistic Support Force from August 2021 to August 2023 were enrolled and the data from the right eyes were collected for analysis. According to the method of optometry test modality, they were divided into 0.05 D group and 0.25 D group, with 200 eyes in each group. The differences were compared between the two groups of patients in intraoperative corneal ablation thickness, uncorrected distance visual acuity(UDVA), high-order corneal aberrations(HOA), spherical aberrations, vertical coma, horizontal coma and trefoil aberrations before and at 1, 3 and 6 mo after surgery. Additionally, the percentage of eyes with residual spherical equivalent(SE)≤±0.25 D, postoperative visual symptoms and scores on the quality of visual(Qov)were compared between the two groups at 6 mo after surgery.

RESULTS: The corneal ablation thickness in the 0.05 D group was 92.78±16.56 μm, which was slightly higher than that in the 0.25 D group(83.24±17.33 μm; P<0.001). The UDVA at each postoperative time point in the 0.05 D group was superior to that in the 0.25 D group(all P<0.001). The HOA, spherical aberration, horizontal coma and vertical coma in the two groups at 1, 3 and 6 mo after operation were higher than those before operation(all P<0.05). The spherical aberration in the 0.05 D group at each time point after surgery were higher than those in the 0.25 D group, and vertical coma were lower than those in the 0.25 D group(all P<0.05). At 6 mo postoperatively, the percentage of eyes with residual SE ≤±0.25 D in the 0.05 D group was 97.5%(195 eyes), which was higher than 87.5%(175 eyes)in the 0.25 D group(P<0.05). The most common adverse visual symptoms after SMILE in both groups were hazy vision and glare. The total Qov score in the 0.05 D group was 0.35(0.24, 0.55), which was lower than \〖0.62(0.32, 0.89)\〗 in the 0.25 D group(P<0.05).

CONCLUSION: Compared with conventional 0.25 D interval spherical lens optometry-guided SMILE, the 0.05 D interval spherical lens optometry-guided SMILE for the correction of low-to-moderate myopia has better predictability and can achieve better vision and visual quality.