The Application Of Anterior Lens Capsule In Two-sites Phacotrabeculectomy

Objectives1. To observe the anti-scarring efficacy of using the anterior lens capsule as an adjunct during phacotrabeculectomy in rabbits’eyes.2. To compare the clinical outcomes of anterior lens capsule with mitomycin C applied in phacotrabeculectomy and evaluate the safety and effectiveness of the anterior lens capsule.Methods1. Animal experiment:Twenty rabbits were randomly divided into two groups; each group was consisting of10rabbits (20eyes). Phacotrabeculectomy with the application of anterior lens capsule were performed on one eye (group ALC) and phacotrabeculectomy alone on the other eye (group Trab) in the first group. Mitomycin C (group MMC) was performed on one eye and anterior lens capsule on the other eye in the second group. The reaction of anterior segment, type and function of the filtering bleb, IOP were observed after surgery. The pathological changes in filtering trace were investigated on days3,7,14,21,28after surgery.2. Clinical research:Sixty patients with coexisting cataract and uncontrolled glaucoma were performed by two site phacotrabeculectomy and at the end of the surgery the removed anterior lens capsule was placed under the scleral flap in group ALC and mitomycin C in group MMC. Postoperative evaluations included IOP, BCVA, type of the filtering bleb and complication were conducted on the months1,3,6and12.UBM and visual field examination were performed regular. All the data were analyzed by the SPSS16.0statistical soft ware package.Results1. Animal experiment:There were no statistical difference among the three different surgery groups in conjunctival congestion and corneal opacities on days1,5after surgery; the reactions of anterior chamber were no statistical difference on days1,3,7,14after surgery. There were no stimulation symptoms caused by lens capsule in all eyes. The proportion of functional filtering bleb were14.3%(1/7),92.9%(12/14) and85.7%(6/7) in these three groups respectively on days21after surgery, this difference was significant(x2=13.077, P<0.05). The differences of postoperative IOP among the three groups were significant on days14,21after surgery (x2=14.377,10.279, P<0.05). Histopathology examination showed that the passage of aqueous humor outflow kept open on7day after surgery in group ALC and MMC while partly closed in group Trab, the structure of anterior lens capsule were integrity and clear. The filtering trace was completely blocked by the scar tissue in group Trab at28day, the remote trace closed and proximal one opened a small part in group MMC, while the passage opened completely in group ALC, the edge of the anterior lens capsule became dull, there were still no lymphocytes appeared.2. Clinical research:In group ALC the preoperative IOP improved from22.28±10.81mmHg to12.24±2.91mmHg. In group MMC, the IOP improved from26.50±12.69mmHg to11.15±2.87mmHg. There was statistically significant difference (tALC=4.851, P<0.05; tMMc=6.701, P<0.05). The degree of IOP drop between two groups was no statistically difference at each time point. Comparison of the BCVA between preoperative and postoperative1year revealed a significant improvement in both the groups (tMMC=-5.294, P<0.05; tMMC=-4.027, P<0.05). There was no statistical difference between the ALC and the MMC groups in the formation of functional filtering blebs (x2=0.912, P>0.05) on postoperative1year. The success rate of the surgery was86.2%(26/29) in group ALC and93.5%(29/31) in group MMC, there was no statistically significant difference between both the groups (x2=0.897, P>0.05). The mean number of eye drops used preoperatively was2.45in group ALC and2.61in group MMC. The mean number of eye drops used on postoperative1year was0.14in group ALC and0.06in group MMC. There was statistically significant difference between preoperation and postoperation (tALC=13.970, tMMC=14.772, P<0.05). The postoperative complications between two groups resolved or eased in two weeks after operation, there was no rejection in group ALC. The visual field was stable on postoperative1year compared with preoperative. The filtration intervals were clear on postoperative3month of all patients and anterior lens capsule were found in some ones in group ALC.Conclusions1. The efficacy of reducing IOP between ALC and MMC in phacotrabeculectomy was similar, however the maintain time of filtering corridor was long in group ALC.2. Anterior lens capsule used in combined surgery of glaucoma and cataract could get comparable outcome as MMC in decrease IOP effectively, improve VA and sustain visual field. The ALC is safe and effective.