Refractive errors in high myopic eyes after phacovitrectomy for macular hole

AIM: To examine the refractive prediction error in high myopic eyes after phacovitrectomy.METHODS: This retrospective comparative case series included 91 eyes(18 high myopic eyes and 73 non-high myopic eyes) of 91 patients who underwent successful phacovitrectomy(phacoemulsification, intraocular lens implantation, and pars plana vitrectomy). The high myopic eyes were defined as the eye with more than 26.0mm of axial length. The postoperative prediction error of mean error and mean absolute error were evaluated at4 mo postoperatively. Axial length and keratometry measurement were performed preoperatively and 4mo postoperatively using the IOL Master.RESULTS: The refractive outcome after phacovitrectomy showed significantly greater myopic shift in the high myopic eyes [-1.08 ±0.87 diopters(D)] than that in the non-high myopic eyes(-0.43 ±0.63 D, P =0.004). Axial length and keratometric value in the high myopic eyes were significantly increased(P =0.043, 0.037 respectively),whereas those in the non-high myopic group were not significantly increased(P =0.135, 0.347 respectively). The change of the axial length in the myopic eye(0.46±0.28 mm)was greater than that in the non- high myopic eye(0.11 ± 0.34 mm; P 【0.001).CONCLUSION: High myopic eyes showed more myopic shift than non-high myopic eyes after phacovitrectomy.The cause of myopic shift in high myopic eyes seems tobe attributed to actual elongation of the axial length in high myopia.

Measurement of retinal thickness in macular region of high myopic eyes using spectral domain OCT

AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three groups according to their refractive error/axial length: low and medium myopia group(LMMG),high myopia group(HMG) and super high myopia group(SHMG). Cirrus HD-OCT was used to evaluate total average macular thickness,central subfield thickness,inner/outer macular thickness and macular volume. The differences among experimental groups were analyzed by one-factor analysis of variance. Associations between macular thickness and refractive error/axial length were analyzed by Pearson correlation analysis. ·RESULTS: There was no significant difference in age among the three groups(P =0.2789). The mean refraction error in the LMMG,HMG,and SHMG groups was-2.49 ± 1.38D,-8.53 ±1.95D and-13.88 ±1.76D,respectively(P 【 0.001). The central subfield thickness of three groups was 244.56 ±12.19μm,254.33 ±11.61μm and 261.75 ± 11.83μm,respectively,and there were statistically significance between random two groups. The total average macular thickness,inner/outer macular thickness,and macular volume decreased with increased myopia/axial length. Average foveal thickness had negative correlations with refractive error(P 【0.001),and positive correlations with axial length. The inferior and temporal inner macular thickness,all the quadrants of outer ring,total average macular thickness and macular volume featured positive correlations with refractive error,and negative correlations with axial length. Average foveal thickness,superior and temporal innermacular thicknesses,and temporal outer macular thickness was lower in females compared to males. ·CONCLUSION: With an increase in myopia degree/axial length,the average foveal thickness increased and the inner/outer macular thickness decreased. Females featured thicker average foveal thickness,and thinner macular thickness compared to males.