ABSTRACT
AIM: To evaluate the efficacy of implantable collamer lens (ICL)-V4c implantation in the correction for high myopia. METHODS: This retrospective analysis collected twenty-five patients (43 eyes) with high myopia treated with ICL/TICL implantation from September to December 2016 at Department of Ophthalmology, West China Hospital. Routine ophthalmic examinations were performed. The patients were followed 3mo to monitor uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refractive error, intraocular pressure, corneal endothelial cell count, contrast sensitivity and scores for Quality of Life lmpact of Refractive Correction Questionnaire ( QIRC ). Statistical analyses were performed using repeated measures ANOVA, LSD-t test and paired-samples T test. RESULTS: Postoperative UCVA and BCVA were significantly higher than before surgery (all P<0. 01). Postoperative spherical mirrors at all time points were lower than before surgery(all P<0.01),and there was no significant difference between the different time point postoperative (all P>0. 05). The safety index in 3mo postoperatively was 1.38士0.24 and the effective index was 1. 22士0. 15. There was no statistical difference in intraocular pressure between preoperative and postoperative time points (F=1.464, P=0.215). There was no statistical difference in endothelial cell density at 3mo after surgery compared to preoperative (t=-0.544, P= 0. 586). The postoperative Log contrast sensitivity (LogCS) of 12.0 cycles per degree (c/d) and 18.0 c/d were significantly higher compared to the preoperative (F=4.347, P=0.010; F=4.539, P=0.005; respectively), but other (the postoperative LogCS of 3.0 c/d and 6.0 c/d) differences were statistically insignificant (F=1.094, P=0.354;F=1 325,P=0.271;respectively). There was no significant difference in the amount of change in the QIRC scores between preoperative and postoperative(F=2.669, P=0 094). CONCLUSION: ICL V4c implantation is a safe and effective method for the correction of high myopia.
ABSTRACT
AIM:To compare CASIA SS-1000 and Sirius OCT sweep anterior segment analyzer instrument for measuring normal corneal vertex thickness (CCT) and the thinnest corneal thickness (TCT) results the difference,correlation and consistency,and provide a theoretical basis for clinical application.METHODS:This was a prospective study.A total of 34 normal subjects were collected.The subjects were measured by the same skilled operator.The SS-1000 OCT was first used,and then the corneal thickness was measured repeatedly by Sirius anterior segment analyzer.Paired t test and Bland-Altman were used to evaluate the consistency of corneal apex and corneal thinnest point between SS-1000 OCT and Sirius anterior segment analyzer.RESULTS:The mean corneal apex measured by SS-1000 OCT and Sirius corneal topography were 517.62± 25.29μm and 518.47±27.23μm CCT,respectively.The thinnest points of SS-1000 OCT and Sirius anterior segment analyzer CCT were 513.53±25.06μ m and 515.32± 26.69μm,respectively.Paired t test showed that the difference on corneal thickness of vertex was not statistically significant (P＞0.05),but the thinnest corneal thickness was statistically significant (P＜ 0.05).Pearson analysis of the two devices,the correlation is 0.969,0.965.The results of 95％ consistency limiting analysis on the corneal vertex thickness by Bland-Altman was (-14.22μm,12.52μm),that of the thinnest corneal thickness was (-15.61μm,12.03μm),4％ (3/68) was out of the 95％ consistency limiting,but the thinnest corneal thickness was of a little larger differences.CONCLUSION:SS-1000 OCT measurement of CCT and Sirius anterior segment analyzer is highly consistent,in clinical work can be considered alternative,but the thinnest point of the cornea can not be replaced each other.