The Alteration Of Anterior Chamber Angle And Related Factors After Posterior Chamber Intraocular Lens Implantation In Phakic Eyes

ObjectiveTo observe the change of anterior chamber angle after posterior chamber intraocular lens(ICL)implantation in phakic eyes,analyze the correlation between postoperative anterior chamber angle and preoperative anterior segment parameters and the vault.MethodThis research is prospective.The clinical data of 31 patients(55 eyes)with myopia who received phakic posterior chamber intraocular lens(EVO ICL)implantation in the Department of Ophthalmology,the First Affiliated Hospital of Zhengzhou University between Sep.2018 to Sep.2019 were collected.Visante anterior segment OCT examination were performed in all cases before,1 day and 1,3 months after surgery.The nasal and temporal anterior chamber angle(ACA)and the vault were observed and compared between before and after surgery.To analyzed the correlation between postoperative anterior chamber angle and the preoperative spherical equivalent,axial length,horizontal corneal diameter(white to white),anterior chamber depth,anterior chamber volume,horizontal keratometry,anterior chamber angle,ICL diameter and the vault.Results1.The difference in nasal and temporal anterior chamber angle before phakic intraocular lens(ICL)implantation was not significant(P>0.05).the difference was statistically significant in nasal and temporal anterior chamber angle at 1 day after surgery(P<0.05),the temporal side is slightly wider than the nasal side.The difference in nasal and temporal anterior chamber angle was not significant at 1,3 month after surgery(P>0.05).2.The difference in nasal anterior chamber angle before and after surgery was significant(P<0.05).The nasal anterior chamber angle was reduced by 45%一 50%after surgery.The difference in temporal anterior chamber angle before and after surgery was also significant(P<0.05).The temporal anterior chamber angle was reduced by 44%～49%after surgery.The difference in nasal anterior chamber angle at any two time points:1 day,1 month and 3 months after surgery and the difference in temporal anterior chamber angle at any two time points:1 day,1 month and 3 months after surgery were not significant(P>0.05).3.The average vault of phakic eyes was 0.64±0.18 mm at 1 day after ICL implantation,0.54±0.15 mm at 1 month after surgery and 0.53 ± 0.16 mm at 3 months after surgery.During the follow-up period,the vault decreased significantly from 1 day after operation to 1 month,decreased smoothly from 1 month after operation to 3 months.4.The average intraocular pressure of phakic eyes before ICL implantation was 15.28 ± 2.85 mmHg,15.56± 3.44 mmHg at 1 day after surgery,14.88 ± 2.52 mmHg at 1 month after surgery and 14.82 ± 2.24 mmHg at 3 months after surgery,the difference was not statistically significant(P>0.05),there was not significant difference in intraocular pressure due to anterior chamber angle reduced after posterior chamber intraocular lens implantation in phakic eyes.5.The postoperative anterior chamber angle was correlation with the anterior chamber volume,anterior chamber depth and preoperative anterior chamber angle(P<0.05),especially the preoperative anterior chamber angle(P=0.000),there was no correlation with ICL diameter,vault,preoperative spherical equivalent,axial length,horizontal keratometry and white to white(P>0.05).ConclusionThe anterior chamber angle was significantly reduced after posterior chamber intraocular lens implantation in phakic eyes,and the anterior chamber angle was basically stable during the follow-up period,without further narrowing.