| Penetrating keratoplasty,also known as total keratoplasty,refers to a surgery that a healthy and pellucid donor cornea is used to replace the diseased host cornea.It is most suitable for keratoconus,repeated corneal transplantation,corneal dystrophy,a variety of causes of corneal leukoma,corneal injury and blood staining of cornea,etc.It also applies to patients with corneal dissolution,such as patients with corneal perforation caused by severe corneal perforation,In order to explore the clinical methods to prevent canine corneal transplantation rejection and to promote postoperative corneal healing,the method combined eye treatment of tobramycin,dexamethasone(DEX),cyclosporine A(CsA)and basic fiber cell death factor(bFGF).Through the clinical score of canine corneal edema,turbidity,neovascularization,and fluorescein sodium staining,the detection of intraocular pressure,tear volume,peripheral blood leukocyte count,and the observation of corneal pathological section,this experiment will evaluate the clinical treatment effect of drug combination in treating canine penetrating keratoplasty,which provides a theoretical basis for the clinical treatment of canine corneal transplantation.In this experiment,54 healthy dogs were selected,aged approximately 1 year old,weighing 4-8 kg,36 were reciepient dogs,and 18 of them were donor dogs.36 dogs were divided into four groups:group A was tobramycin eye drop group;group B was tobramycin + dexamethasone eye drop group;group C was tobramycin+dexamethasone + cyclosporine eye drop group;group D was tobramycin + dexamethasone + cyclosporine + bFGF(basic fibroblast growth factor)eye drop group.The interval between all drugs used for eye drop was 30 min,1-2 drops/time,4 times/day.Eye secretion was observed daily after operation.The condition of corneal turbidity,neovascularization,edema and fluorescein sodium staining were observed using the slit-lamp at 3,7,14,21 and 35 days after operation,meanwhile,a complete blood count,intraocular pressure,and tear volume was measured.The observation of corneal pathological section was performed on the 14th and 35th day after operation.The results are as follows:(1)Canine corneal transplantation method:In this experiment,all dogs were shaved 3d before surgery to avoid contamination and stimulation on the day of surgery.Oneirogenicgeneral anesthesia was used to ensure that the animals remained calm and quiet throughout the surgery.In order to fully expose the eye,the surgical incision was made at the outside corner of the eye.Surgery was performed using an ophthalmic microscope to ensure a consistent depth of suture.After surgery,all dogs received Elizabeth Collins,which improved the efficiency and success rate of the surgery.(2)Comparison of canine corneal turbidity:on the 3rd day,corneas of each group were mildly turbid,and the difference was not significant(p>0.05);on the 7th day,the turbidity of group A and group B increased slightly,and compared with 0 day,there was no difference(p>0.05);on the 14th day,the corneal opacity of the four groups increased,moreover,the turbidity was the highest in group A,and the difference between group D and group A was significant(p<0.05);on the 21st day,the corneal opacity of group A and B continued to increase,however,the turbidity of group D was lower,and compared with group A,the difference was significant(p<0.01);on the 35th day,the corneal opacity in group A reached the peak value,but the other three groups were decreased,meanwhile,the corneal of group D was completely transparent(p<0.01),and significantly different from group A.(3)Comparison of canine corneal neovascularization:on the 3rd day,there was no new blood vessels apparent in the corneas of all four groups;on the 7th day,the cornea of group A began to appear neovascularized,and there was significant difference between group D and group A(p<0.05);on the 14th day,there was also neovascularization in group B,but less than group A,and group D and group A were significantly different(p<0.01);On the 21st day,the length of the new vessels increased in group A and B,and a small amount of neovascularization occurred in group C and D,furthermore,there was significant difference between group D and group A(p<0.01);on the 35th day,the corneal neovascularization reached maximum in group A and B,and there was a significant difference between group D and group A(p<0.01).(4)Comparison of canine corneal edema:on the 3rd day,all experimental dogs had mild edema;on the 7th day,the corneal edema was the most severe in group A,and there was significant difference between group D and group A(p<0.05);on the 14th day,corneal edemawas exacerbated in group A and B;on the 21st day,the corneal edema degree began to alleviate in groups B and D,which were significantly different from that in group A(p<0.01);on the 35th day,the corneal edema in group A reached the highest level,and the remaining three groups were decreased.The edema in group D was completely eliminated,and the difference was significantly different from group A(p<0.01).(5)Comparison of fluorescein sodium staining:on the 3rd day,the cornea of the four groups was colored,and there have no significant difference(p>0.05);after the 7th day,the staining area of group D was significantly smaller than that of the first three groups,which was significantly different from that of group A(p<0.01).(6)Comparison of intraocular pressure:on the 3rd day after surgery,the intraocular pressure of all experimental dogs was lower;on the 7th day after surgery,the intraocular pressure within the normal range;group D had the fastest recovery of intraocular pressure,and comparing with the group A,the difference was very significant(p<0.01).(7)Comparison of tear volume:on the 3rd day,the tear volumes of all groups were increased;on the 7th day,the tear volumes of group B,C and D began to decline,and the tears of group D restored the fastest;on the 21st day,the amount of tears in group C and D returned to normal range,and the difference between group D and group A was significant(p<0.01).(8)Pathological observation:the corneal stroma fiber of the group A was the most chaotic,and the recovery rate of the epithelium was slower,moreover,the division phenomenon of the epithelium and the stromal were observed on the 35th day after operation;compared with group A,the corneal stroma fiber arrangement of group B and C was relatively regular,and epithelial cells restored more completely;the recovery rate of corneal epithelial cell layer of group D was the fastest,and the corneal surface was smooth,meanwhile,corneal stroma fibers were arranged in neat rows.From the above results,it was found that combining tobramycin,dexamethasone,cyclosporine and basic fibroblast growth factor drop to eyes could significantly reduce the inflammatory response after canine corneal transplantation and prevent the occurrence of immune rejection,which would not only help promote the healing of corneal epithelium and matrix as soon as possible,but reduce the occurrence of postoperative complications. |
PDF Full Text Request