ABSTRACT
AIM: To observe the effect of eccentricity of the optical treatment zone on retinal defocus after wearing orthokeratology lens for 12mo.METHODS: In this case-control study, a total of 120 myopic patients(120 eyes)who completed the fitting in our hospital from March 2021 to September 2021 and insisted on wearing orthokeratology lenses for 12mo were selected. According to the eccentricity after wearing lenses for 12mo, they were divided into the low eccentricity group(<0.5mm, 58 cases, 58 eyes)and the moderate and high eccentricity group(≥0.5mm, 62 cases, 62 eyes). The optical treatment zone diameter(OTZD), eccentricity, axial length(AL), pupil diameter(PD)and refraction difference value(RDV)were evaluated after 12mo of wearing orthokeratology lenses, and the correlation between RDV and eccentricity was analyzed.RESULTS: After wearing orthokeratology lenses for 12mo, AL growth and RDV at 30°～40° and 40°～53° from the fovea were significantly lower in the moderate and high eccentricity group than in the low eccentricity group(all P<0.05). In all patients, RDV at 40°～53° from the fovea was positively correlated with AL growth and OTZD(rs=0.544, 0.333, both P<0.01), and negatively correlated with eccentricity(rs=-0.224, P=0.014).CONCLUSION: Peripheral retinal defocus is related to eccentricity and OTZD after wearing orthokeratology lenses. The greater eccentricity and the smaller OTZD within a certain range can induce more peripheral retinal myopic defocus, leading to a better control of AL growth.
ABSTRACT
AIM: To observe and compare the changes in retinal peripheral refraction and aberrations after femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK)versus small incision lenticule extraction(SMILE)for myopia correction.METHODS: A total of 71 patients(71 eyes)with myopia who underwent FS-LASIK from October 2022 to April 2023 in our hospital were selected as the FS-LASIK group, and 80 patients(80 eyes)with myopia who underwent SMILE were selected as the SMILE group. All patients underwent corneal wavefront aberration measurement and multispectral refractive topography preoperatively and 3mo postoperatively, as well as refraction difference value(RDV)in the range of 0°～10°, 10°～20°, 20°～30°, 30°～40°, and 40°～53° in the annulus of the retina, which were recorded as RDV-(0°～10°), RDV-(10°～20°), RDV-(20°～30°), RDV-(30°～40°), and RDV-(40°～53°). The results of two groups of patients were compared.RESULTS: No significant differences were observed in RDV-(0°～10°), RDV-(10°～20°), RDV-(20°～30°), RDV-(30°～40°), RDV-(40°～53°)between the two groups at 3mo post-operation(all P>0.05). Furthermore, the RDV-(20°～30°), RDV-(30°～40°)and RDV-(40°～53°)of the two groups at 3mo postoperatively were all significantly lower than those preoperatively(all P<0.05). The changes in coma(horizontal)and spherical aberration(SA)at 3mo postoperatively were smaller in the SMILE group [0.106(0.056, 0.171)and 0.115(0.081, 0.182)μm] than in the FS-LASIK group [0.206(0.104, 0.355)and 0.197(0.128, 0.254)μm](Z=-4.170, -5.016, all P<0.05). A negative correlation was found between postoperative SA and postoperative RDV-(10°～53°)(rs=-0.205, -0.181, -0.226, -0.244, all P<0.05).CONCLUSION: Both FS-LASIK and SMILE reduced retinal hyperopic defocus in the peripapillary macular range of 20°～53° eccentricity, and the postoperative changes in coma(horizontal)and SA were smaller with SMILE than with FS-LASIK. There was a certain correlation between postoperative SA and postoperative retinal peripheral defocus.