Safety And Effectiveness Of The Soft-Shell Technique During Phacoemulsification In Patients With Diabetes And Cataract

Background:Nowadays,many domestic and abroad studies have showed that the rate of corneal endothelial cell loss in the patients with diabetes and cataract is obviously more than that in the ones just with age-related cataract after phacoemulsification, which indicates that the corneal endothelial cells in the old patients with diabetes are much easier to be damaged.This phenomenon may be associated with the vulnerability of corneal endothelial cells.Therefore,during the cataract surgery,we should pay more attention to the corneal endothelial cells and try to protect them and decrease the complications.Soft-shell technique has become a relatively mature technology in phacoemulsification.Many clincal studies have showed that in the cataract patients without any other diseases,the rate of corneal endothelial cell loss after using soft-shell technique is much lower than that with other ophthalmic viscoelastic device.Meanwhile,some other studies have also indicated that soft-shell technique has more benefits to visual recovery and can reduce the incidence of corneal edema in the patients with glaucoma or Fuchs' endothelial dystrophy.However,the safty and the effectiveness on protecting corneal endothelial cells of soft-shell technique in the patients with diabetes and senile cataract are still not clear.So in our study,we try to evaluate the safty and effectiveness of soft-shell technique in patients with diabetes and cataract,and provide the clinical evidence for the use of soft-shell technique in these patients.Objectives:To evaluate the safety and effectiveness of the soft-shell technique in phacoemulsification in patients with diabetes and cataract.Methods:1.Forty-six eyes of 38 senile cataract patients with diabetes at the age of old 50～80 years old were selected.The visual acuity,intraocular pressure,corneal endothelial cell density,and central corneal thickness were evaluated preoperatively.They were classified randomly into two groups and treated with phacoemulsification and intraocular lens(IOL)implantation.One group used the soft-shell technique with DuoVisc(Viscoat and ProVisc)(soft-shell group),and the other group used sodium hyaluronate(control group).All surgerys were completed by the same experienced doctor.2.The visual acuity,intraocular pressure,silt-lamp microscope,funduscope, corneal endothelial cell density,and central corneal thickness were examined at 1 day, 1 week,1 month and 3months after surgery.3.Data were analyzed using a statistical software program(SPSS for Windows, version 13.0,SPSS Inc.).Data were expressed as the mean±SD.Student's two tailed t-test,chi-square test were used where appropriate.P-value＜0.05 was considered statistically significant.Results:1.All patients were examined at all follow-up visits.No complication was found operatively and postoperatively.No posterior opacification happened.2.Mean age of two groups were 71.2Y±8.3(SD)and 69.8±9.2 Y respectively. There were no significant differences between the two groups in the distribution of the visual and lens grade(P＞0.05).3.The mean ultrasound time(UST)and effective US power(USP)were, respectively,8.62 minutes±3.28(SD)at 5.32%±2.98%in DuoVisc group and 7.57±2.94 minutes at 5.41%±2.07%in control group.The differences between the two groups were not statistically significant(P＞0.05). 4.The uncorrected visual acuity(UCVA)and the best corrected visual acuity (BCVA)showed no significant differences between the two groups in 1 day,1 week,1 month and 3 months after surgery(P＞0.05).5.The intraocular pressure showed no significant differences between the two groups in 1 day,1 week,1 month and 3 months after surgery(P＞0.05).6.The central corneal thickness in the control group was 531μm±29(SD) preoperatively and 573±571μm 1 day after surgery(P=0.018),a significant increase. The thickness returned to preoperative levels gradually from 1 week to 3 months.The central corneal thickness did not change significantly in the soft-shell group(P＞0.05).7.The rate of endothelial cell loss 3 months after surgery was 12.7%±10.9%in the softshell group and 20.1%±11.3%in the control group.There are significant deferences between the two groups(P=0.002).Conclusion:The soft-shell technique is safe and effective in protecting corneal endothelial cells during phacoemulsification in patients with diabetes and cataract.