Effect Of Preoperative Dilation Time On Phacoemulsification Combined With Atrial Angle Separation For Primary Angle-closure Glaucom

Objective:To observe phacoemulsification combined with goniosynechialysis(phacoemulsification combined with goniosynechialysis,Phaco+GSL)effect of mydriasis at different time before surgery on patients with primary angle closure glaucoma(primary angle closure glaucoma,PACG),guiding clinical selection of mydriasis time before surgery in patients with glaucoma.Methods:In this study,60 patients(60 eyes)with PACG admitted to the ophthalmology department of the People’s Hospital of Guangxi Zhuang Autonomous Region from November2021 to December 2022 were selected,including 18 patients(18 eyes)with acute angle-closure glaucoma(acute angle-closure glaucoma,AACG).Forty-two cases(42 eyes)of chronic angle-closure glaucoma(chronic angle-closure glaucoma,CACG)were divided into three groups according to random number table sampling method: myopathy 20 minutes before surgery in group A,myopathy 30 minutes before surgery in group B and myopathy 1hour before surgery in group C,with 20 cases(20 eyes)each.All patients were in supine position and were given compound topicamide eye drops once every 5 min for a total of 3times.Preoperative and postoperative intraocular pressure(intraocular pressure,IOP),visual acuity,IOP before and after mydriasis,pupil diameter,anterior chamber depth(anterior chamber depth,ACD)and lens thickness(lens thickness,LT)were compared and cumulative dissipated energy(cumulative dissipated energy,CDE)of each group,and the correlation between the indicators was analyzed.Results:(1)Postoperative visual acuity of the three groups was significantly improved compared with that before surgery,and the difference was statistically significant(P < 0.001).There was no significant difference between the three groups(P=0.541).(2)Postoperative IOP of the three groups was lower than that before surgery,and the difference was statistically significant(P < 0.001).The reduction range of IOP was as follows: 1h before surgery > 30 min before surgery > 20 min before surgery,and the difference was statistically significant(all P < 0.05).IOP after mydriasis was higher than that before surgery,and the difference was statistically significant(P < 0.001).The increase range of IOP was as follows: 1h before surgery > 20 min before surgery and 30 min before surgery,the difference was statistically significant(P < 0.001,P=0.04),but there was no statistically significant difference between30 min before surgery and 20 min before surgery(P=0.678).(3)ACD was deepened,LT was thinner and pupil diameter was increased after mydilation compared with before mydilation in the three groups,the differences were statistically significant(all P < 0.001),and 1h before surgery > 30 min before surgery > 20 min before surgery,the differences were statistically significant(all P < 0.05).(4)There was no significant difference in CDE required by surgery among the three groups(P=0.623),and there was significant difference in operation time among the three groups(P < 0.001).Operation duration was 20 min before surgery > 30 min before surgery > 1 hour before surgery,with statistical significance(all P < 0.05).(5)Pupil diameter difference was positively correlated with ACD difference,LT difference,IOP difference 1(difference between preoperative and postoperative IOP),IOP difference 2(difference between post-mydriasis and pre-mydriasis IOP)(P < 0.001).(6)ACD difference was positively correlated with LT difference,intraocular pressure difference 1 and intraocular pressure difference 2(all P < 0.05).(7)There was a significant positive correlation between LT difference and IOP difference 1 and IOP difference 2(all P < 0.001).(8)IOP difference 1was positively correlated with IOP difference 2(P=0.001).(9)Operation time was negatively correlated with pupil diameter difference,ACD difference,LT difference,IOP difference 1and IOP difference 2(all P < 0.001).(10)There was no significant correlation between the other observation indicators.Conclusion:(1)This study IOP increased after mydriasis in all three groups,but the range of 2 mm Hg was of limited clinical significance and did not increase the incidence of surgical risks and complications.(2)This study with the increase of mydriasis time before surgery,pupil diameter increased,ACD deepened,LT became thinner,operation time decreased,and postoperative IOP decreased.(3)PACG patients undergoing Phaco+GSL surgery can obtain better surgical effect and clinical efficacy with mydriasis 1h before surgery.