Comparison Of The Effects Of Drainage Nails And Trabeculectomy In The Treatment Of Canine

Glaucoma is one of the main causes of irreversible vision loss in dogs.At present,trabeculectomy combined with mitomycin C is the most commonly used method for the treatment of canine glaucoma in veterinary clinics.However,this operation has great damage to the eye and is easy to cause complications such as hemorrhage in the anterior chamber and low intraocular pressure.Ex-PRESS glaucoma drainage nail is a new type of drainage device implant that has emerged in recent years,which is simple to operate and has remarkable postoperative effects,and is often used in human glaucoma treatment,but it is rarely reported to be applied to dogs.In order to evaluate the clinical efficacy of Ex-PRESS glaucoma drainage nails in the treatment of dog glaucoma,this trial performed Ex-PRESS glaucoma drainage nail implantation and trabeculectomy in both eyes of model dogs on the basis of the successful establishment of glaucoma model,and observed and compared the postoperative effects and surgical operation characteristics of the two surgical types,as follows:In this experiment,a total of 14 healthy beagles were selected and divided into a module(n=12)and a normal group(n=2).Compound carbomer was injected into the anterior chamber pupil area of the model dog,and the binocular high intraocular pressure model was successfully established,and the normal group of dogs did not do any treatment.On the 7th day of modeling,the modeling dog’s eyes were surgically treated: trabeculectomy was performed on the left eye,that is,the TL group;Ex-PRESS glaucoma drainage nail implantation in the right eye,the Ex-PRESS group.Mitomycin C is used in combination with both procedures.The anterior segment parameters(intraocular pressure,anterior chamber depth,ocular axis,etc.)were measured before(0 d),7 d,and 8 weeks after surgery(14/21/28/35/42/49/63 d),and the formation and complications of follicles were recorded.Aqueous humor was extracted from normal dogs and model dogs at 21,35 and 63 days after surgery,the expression of inflammatory factors was detected by ELISA,and the tissues of the filter area were collected for histopathological and RT-PCR detection,and the scarring and inflammatory response of the filtration area in the surgical department were analyzed.The results showed that compared with the pre-mold(0 d),the intraocular pressure increased,the anterior chamber depth deepened,the corneal curvature K2 increased,and the length of the eye axis increased(P<0.001)after the mold(7 d).Compared with7 d,dogs in the postoperative TL group and EX-PRESS group had reduced intraocular pressure,shallow anterior chamber depth,and shortened ocular axis length(P<0.001).Compared with 0 d,there were no significant differences in intraocular pressure and anterior chamber depth between the TL group and EX-PRESS group(P>0.05),corneal curvature K2 and eye axis length increased at 21 and 35 days postoperative(P<0.05),and corneal curvature K2 and axial length at 63 days(P>0.05).At 7 days and 8 weeks after surgery,there were no significant differences in anterior segment parameters between the TL group and the EX-PRESS group(P>0.05).At 63 d,the functional follicular formation rate was 75.00% in the TL group and 83.33% in the Ex-PRESS group.The postoperative complication rate was 41.67% in the TL group and 25.00% in the Ex-PRESS group.H&E staining of the filter zone tissue showed that at 21 and 35 days,inflammatory cell infiltration,fibroblast proliferation,dense collagen fiber deposition and arrangement disorder were seen in the TL group and the Ex-PRESS group,among which there were more inflammatory cell infiltration in the TL group.At63 days,there was no obvious inflammatory cell infiltration in either group,the filter area was scarred,and the filter tract remained basically open.The results of immunohistochemical staining showed that scarring-related factors TGF-β and α-SMA were negatively or weakly positive under the conjunctiva of normal groups,and positive expressions were positive in the TL group and Ex-PRESS group after surgery(21,35 and 63 days).Compared with the Ex-PRESS group,there was no significant difference in TGF-β and α-SMA expression in the TL group.RT-PCR measured TGF-β mRNA expression with results consistent with changes in protein levels.The results of ELISA assay showed that at 21 and 35 days,the expression of inflammatory factors(IL-1β,IL-6 and TNF-α)in the TL group and the Ex-PRESS group was significantly higher than that in the normal group(P<0.001),and the expression of inflammatory factors in the TL group was higher than that in the Ex-PRESS group(P<0.001),and at63 days,the expression of inflammatory factors in both groups decreased and returned to normal levels.Immunohistochemistry and RT-PCR measured the expression of IL-1β,IL-6 and TNF-α in filter region tissues,and the results were consistent with the trend of ELISA determination.In summary,Ex-PRESS drainage nail implantation and trabeculectomy had good intraocular pressure lowering effects.Ex-PRESS drainage nail implantation trabeculectomy is simple to operate,short operation time,no need to remove iris and trabecular tissue,little eye damage,less postoperative complications,light inflammatory response,high safety,can replace trabeculectomy,used in veterinary clinical dog glaucoma treatment.