Evaluation of clinical effectiveness of implantable contact lens for high myopia / 中华实验眼科杂志

ABSTRACT

Background Posterior chamber phakic intraocular lens implantation is a safe and effective method for correction of high myopia.Petacam-assisted observation of the intraocular lens position in the eye after surgery,provides a good way for the evaluation of operation safety.Objective This study was to evaluate the security and effectiveness of posterior chamber (phakic) implantable contact lens (ICL) implantation for high myopia.Methods Twenty-five eyes of eighteen high myopia patients who received ICL implantation were retrospectively analyzed from March 2009 to September 2012.The mean preoperative spherical equivalent (SE) of the patients was (-17.52 ± 1.73) D and the cylinder was (-0.75 ± 0.28) D.The clinical effective indexes included preoperative and postoperative uncorrect visual acuity (UCVA) and best correct visual acuity (BCVA),SE,intraocular pressure (IOP),corneal endothelial cell number and percentage of corneal endothelial hexagon cells.In addition,Pentacam analysis system was used to compare the anterior chamber depth,anterior chamber angle and space between crystal lens and ICL between before and 6 months after operation.Written informed consent was obtained from each patient before any medical procedure.Results ICL was successfully implanted in all the 25 eyes.UCVA was 1.47 ±0.26 and 0.26±0.15 respectively before and after operation,showing a significant difference between them (t =21.71,P =0.00).SE,corneal endothelial cell number and percentage of corneal endothelial hexagon cells were significantly lower than those before operation (SEt =-48.60,P =0.00 ; corneal endothelial cell numbert =13.07,P =0.00 ;percentage of corneal endothelial hexagon cellst =10.79,P＜0.05).Anterior chamber angle was (25.02± 4.77)° 6 months after operation and was smaller than (38.43±4.04)° before operation (t=15.32,P=0.00).No significant differences were found in IOP and anterior chamber depth between before and after operation (IOPt =-1.57,P =0.13 ; anterior chamber deptht =1.46,P =0.16).The spaces between crystal lens and IOL was (363.33± 44.37) μm 6 months after operation,with a significant decline in comparison with (542.17±39.46) μm 1 week after operation (t =20.86,P =0.00).Glare sense appeared in 2 eyes after operation.Conclusions The results indicated that ICL implantation can retain the natural accommodation of lens.ICL implantation appears to be an effective and safe approach to high myopic eyes.However,the changes of corneal endothelial cells after operation should be payed more attention.