Clincical And Pathological Observations On Treatment Of Pterygium With Mitomycin C

Objective:This study focused on using single dose injection of MMC locally in treatment of primary quiescent pterygiums with more than 2mm corneal edge invasion, clinical observations were conducted on these cases.Pathological and immunohistochemistry examinations on pterygium specimens were performed on cases with operation.Having observed their local pathological characteristics,comparatively analyzed the numbers of fibroblasts and neovascularizations.At the same time, analyzed the expression of TGF-β1 and VEGF in normal conjunctivas,pterygium and pterygium with treatment of MMC respectively in immunohistochemistry study. Evaluated the efficacy of using MMC in treatment of pterygium in order to seek its treatment mechanism and provide a theoretical basis for further exploring its ideal administration route,dosage and time.Methods:1.The cases were divided into four groups:group A,group B,group C and group N.Suffered eyes which need operation were randomly divided into 2 groups according to the sequence of consulting.In group A,pterygiums were directly cut and specimens of pterygiums were kept for pathological study.In group B,single dose MMC,which is 0.1 ml from 0.4mg/ml,was injected into pterygiums through their necks preoperatively.Pterygium resections were done 3 to 10 weeks after injection and specimens were kept for pathological study as well.In group C,single dose MMC,which is 0.1～0.2 ml from 0.4mg/ml,was injected locally into pterygiums through their necks,then follow-ups were done post injections. Group N,5 eyes were observed from normal balbar conjunctiva with other eye diseases but without pterygium.2.H.E.Staining:specimens from group A,B and N were fixed and made into paraffin sections respectively with HE staining to observe histopathological changes.3.Immunohistochemistry study:To analyze and study the expression of TGF-β1 and VEGF in normal conjunctiva,pterygiurns and MMC treated pterygiums respectively.4.Follow-up:Observations were performed to pterygium head,body,recrudescence of pterygium,and eye complications.Results:1.Clinical observation:Some-patients outset the symptom of eye pain after using MMC,and the symptoms relieved one week after using Indomethacin orally or by eye drops.In group C pterygiums were followed up 3 to 12 months post MMC injection, and found that the head of pterygium was paler,tissue was smaller and thinner,the edge of head became filmed,vascular disappeared or became thinner,congestion of the pterygium body decreased with different degrees of vascular contraction.In group B, less adhesions were seen between the head of pterygium and cornea,therefore pterygiums were more easily separated with less bleeding during the operation compared with group A;The incisions were found healed during removal of stitches one week post operation,pale-looking was seen at the exposed part of the sclera and no blood vessels were seen,adhesion between conjunctival incision edge and sclera surface was not so tight compared with group A.36 eyes in 22 cases in group C,one eye was healed,20 eyes were treated with significant obvious results,15 eyes were effective,no eyes are ineffective and no eyes are worsen.There were no complications because of MMC in MMC using group B and C.2.H.E.staining results:the number of blood vessels reduced in the head and body of the pterygium in group B under optical microscope.Small blood vessels shrank near the basement membrane.Fibroblasts reduced and the cell body wane with deep staining and irregular shape nuclear,less clear cytoplasm,inflammatory cells decreased.Vascular examination:more blood vessels were found in group A and B with pterygiums compared with normal conjuctiva(Group N),and these blood vessels scattered. Inflammatory cells significantly increased in group A and B as well,these cells existed more commonly around the vessels.The number of blood vessels and inflammatory cells was significantly decreased in MMC using group.The number of blood vessels in the head and body of pterygium in group A was significantly different(P＜0.05) compared with group B as well.3.Immunohistochemical findings:the expression of VEGF and TGF-β1 was lower in normal normal conjunctiva than this in group A and B,while expression of VEGF and TGF-β1 was higher in group A than this in group B with significant difference(P＜0.05).4.Prognosis in postoperative patients:No real recurrence was seen in two operational groups within one year.However,fiber and vas extend to the limbus obviously means it will be recurrence in group A.Conclusions:1.The number of blood vessels and fibroblasts cells increased significantly in quiescent pterygium than that in normal conjunctiva.2.The expression of VEGF and TGF-β1 increased significantly in quiescent pterygium than that in normal conjunctiva.3.MMC can depress blood vessels and fibroblasts in quiescent pterygium.4.Expression of VEGF and TGF-β1 was affected in quiescent pterygium with treatment of MMC.5.Growth of quiescent pterygium was suppressed with injection of MMC locally,and recurrence rate post operation was reduced as well.And there were no serious eye complications with using low concentration and low dose of MMC.