| Objcetive:To compare the morphology of the uveoscleral pathway of scleral-pool forming trabeculectomy with conventional trabeculectomy in rabbit eyes, and explore the mechanisms of aqueous humor outflow at this surgery.Methods and materials:1. Objects and groups:Thirty rabbits were randomly divided into experimental group, normal control group. The right eyes were performed trabeculectomy with sclera concave pool as experimental groupⅠ, the regular trabeculectomy were operated in the left eyes as experimental groupⅡ,20 rabbits(40 eyes)were used in experimental group. Father more 10 rabbits(20 eyes) without operation served as normal control group.2. Surgery:The conjunctival flap was dissected towards the limbus. The first limbal-based scleral flap of one-thirds thickness,measuring 4 mm perpendicular to and 4 mm, parallel to the limbus, was dissected until the surgical limbus was seen. A second scleral flap was marked out in the area left after the first flap,3mm X 3mm dissection started 1mm above the upper margin of the first flap. Slicing about 2X lmm underneath the trabecular organization,10-0 suture for the sclera flap,and the conjuctival flap was sutured with a continuous suture. GroupⅡdo regular trabeculetcomy.3.Postoperative observation:After a week, slit lamp observe the chamber reaction, cornea, filtering bleb and bleed every day. Record filtering bleb proportion, preoperative and postoperative intraocular pressure monitoring changes, and recorded data statistics analysis. UBM observation of filter corridor and ciliary body. Choose no complication model for the next step.4.Fluorescence tracer experimental:One week postoperatively, the anterior chambers were infused with microamounts of fluorescein isothiocyanate- dextran(FITC-dextran 2mg/ml) as the tracer while did so for normal control group(groupⅠ,Ⅱeach 10 eyes).Three rabbits(two rabbits in experimental group,one rabbit in normal control group) each time were killed at 2,4,6,8,10 hours after infused FITC-dextran, there eyeballs were removed and frozen sections were performed. Degrees of fluorescent intensity of ciliary body, sclera concave pool, suprachoroidal space, anterior and posterior sclera, and choroids were observed under fluorescence microscopy.5. HRP tracer experimental:At 1 week after surgey,10 rabbits in each experimental group and 10 rabbits in normal control group were randomly chosen to receive intracameral injection of horseradish peroxidase(HRP) in rabbit eyes(0.2mg/ml). After survival time of 60 minutes,the rabbits were fixed by carotid artey perfusion. The eyes were enucleated,and freeze section were prepared to observe trace's distribution. Histological structures of these sites were also observed under light microscopy. Massion dyeing observe whether ciliary body away.Result:1. Surgery Results: Preoperative intraocular pressures (IOP) was no sataistically siginificant in groupⅠandⅡ. (18.64±2.68mmHg,18.37±2.75mmHg, T Value 0.32, P=0.96). At a week groupⅠcompared with groupⅡthe intraocular pressure have no statistical significance (P>0.05). After a week of intraocular pressure groupⅠand groupⅡwere significantly lower than were improved, two groups of intraocular pressure comparison, have difference was statistically significant (13.07±2.66mmHg, 13.31±2.50mmHgT Value 0.32, P= 0.29).2.Fluorescence tracer results:Two groups of each part of the fluorescence intensity of comparison after 1 week:the strongest fluorescence intensity of ciliary body, sclera pool and suprachoroidal space, the weakest fluorescence intensity of choroidal and posterior sclera. Experimental groupⅠcompared with experimental groupⅡand normal groups,fluorescent intensities of all uveoscleral pathway site were significantly stonger after Trabeculectomy with Sclera Concave Pool in different time(P<0.01). The fluorescence intensity in normal group were also stronger than of control group(P<0.01). 3.HRP tracer results:After a week, groupⅠsubconjunctival, trabecular meshwork see scattered tan HRP particle size distribution, ciliary body on clearance, ciliary body cavity, under the sclera flap, superchoroidal space and choroidal dense on cavity HRP particles are visible in strong dyed; GroupⅡsubconjunctival see intensive HRP particles are strong dyeing, ciliary body gap, HRP trabecular meshwork see yellowish-brown particles are scattered, under the sclera flap, superchoroidal space and choroidal HRP particles in a cavity saw a weak dyeing, ciliary body cavity HRP not seen in particle size distribution obviously. Control group subconjunctival, trabecular meshwork, ciliary body clearance, iris ciliary body turkestan see scattered HRP particle distribution, superchoroidal space and choroidal HRP particle distribution cavity saw.Conclution:1.The scleral-pool forming trabeculectomy and conventional trabeculectomy in rabbit eyes have the same hypotensive effect at early time.2.Trabeculectomy with sclera concave pool in rabbit eyes except normal trabecular excision filtration esrtuary drainage outside,through the sclera pool also increased the aqueous uveoscleral outflow at early time.3.Aqueous uveoscreal outflow after trabeculectomy with sclera concave pool compared conventional trabeculectomy significantly incleased at early time. Uveoscleral outflow aqueous drainage is one of the main mechanisms in the decrease of the IOP after trabeculectomy with sclera concave pool in rabbit eyes at early time. |
PDF Full Text Request