this prospective clinical study involved 40 patients who underwent primary strabismus surgery at bucheon st . subjects were chosen from patients diagnosed with esotropia or exotropia who were planning to undergo primary horizontal extraocular muscle surgery . exclusion criteria included a history and/or signs of ocular inflammation or hypersensitivity to ocular drugs . a random number was assigned to each patient before the operation and odd numbers were assigned to the fibrin group and even numbers to the suture group . fibrin glue is a tissue adhesive composed of two components that mimic natural fibrin formation . one component contains fibrinogen mixed with coagulation factor 13 and aprotinin , and the other contains thrombin and calcium chloride . when the two components are mixed , thrombin converts fibrinogen into fibrin which is then cross - linked by coagulation factor 13 to create a firm fibrin clot . the fibrin clot is stabilized by aprotinin which also prevents rapid fibrinolysis . in this study , commercially available greenplast fibrin glue ( green cross , seoul , korea ) was prepared according to the manufacturer 's instructions . a human thrombin solution ( 500 iu / ml ) was used to ensure faster fibrin formation . horizontal strabismus surgery under general anesthesia was performed by a single surgeon ( nyk ) . after making an 8 mm peritomy with two radial limbal conjunctival incisions , performed bilateral symmetrical extraocular muscle recession or resection , unilateral recession - resection procedure or unilateral large recession after completing the muscle surgery with the lid speculum in place , the conjunctival wound was closed without tension . excessive tenon 's capsule was excised in all cases . in the suture group , conjunctiva was closed with 4 to 6 stitches of interrupted 8 - 0 polyglactin suture ( vicryl ; johnson & johnson , livingston , uk ) . loose ends of the knot were cut shortly . when closing with glue ( fibrin group ) , the location on the sclera where glue was intended to be applied was dried using a weck - cel sponge . one or two drops of both components were instilled simultaneously on the bare sclera near the limbus and just below the free edges of conjunctiva , which were held with forceps . immediately after applying the glue , the conjunctival edges were pressed together with two forceps for two or three minutes to create firm adhesion along the entire length ( fig . excess glue was trimmed with scissors and a pressure patch was applied for 24 hours . postoperatively , antibiotic and corticosteroid eye drops were applied four times daily for four weeks , then twice daily for two more weeks . total surgical time was recorded for each patient and the conjunctival closure time of each wound was recorded later in ten patients from each group . postoperative pain , tearing , and the extent of inflammation were analyzed and compared at one day , one week , three weeks , and six weeks after surgery in both groups . for pain and tearing , patient 's subjective discomfort was graded on a scale from 0-to-3 ( 0 , total comfort ; 1 , minor discomfort ; 2 , moderate discomfort ; 3 , severe discomfort ) . we modified the facial pain scale - revised   to our 0 to 3 scale for patient and parents ease . when a subjective determination of comfort was difficult to obtain in young children , the parents were asked to provide an estimate . using slit - lamp biomicroscope , we graded the conjunctival inflammation in the operated quadrant using a modified conjunctival inflammatory index   ( table 1 ) in which hyperemia , chemosis , and discharge were rated on a 0 to 3 scale ( 0 , none ; 1 , mild ; 2 , moderate ; 3 , severe ) for a maximum possible inflammation score of 9 . conjunctival incision healing was also investigated by measuring the largest gap size perpendicular to the incision line ( in millimeters ) using a slit - lamp beam . these observations were conducted for all eyes , although only the right eyes were used in cases of bilateral surgery . statistical analysis was performed with mann whitney u - test ( spss ; spss inc . , fibrin glue is a tissue adhesive composed of two components that mimic natural fibrin formation . one component contains fibrinogen mixed with coagulation factor 13 and aprotinin , and the other contains thrombin and calcium chloride . when the two components are mixed , thrombin converts fibrinogen into fibrin which is then cross - linked by coagulation factor 13 to create a firm fibrin clot . the fibrin clot is stabilized by aprotinin which also prevents rapid fibrinolysis . in this study , commercially available greenplast fibrin glue ( green cross , seoul , korea ) was prepared according to the manufacturer 's instructions . a human thrombin solution ( 500 iu / ml ) was used to ensure faster fibrin formation . horizontal strabismus surgery under general anesthesia was performed by a single surgeon ( nyk ) . after making an 8 mm peritomy with two radial limbal conjunctival incisions , performed bilateral symmetrical extraocular muscle recession or resection , unilateral recession - resection procedure or unilateral large recession excessive tenon 's capsule was excised in all cases . in the suture group , conjunctiva was closed with 4 to 6 stitches of interrupted 8 - 0 polyglactin suture ( vicryl ; johnson & johnson , livingston , uk ) . loose ends of the knot were cut shortly . when closing with glue ( fibrin group ) , the location on the sclera where glue was intended to be applied was dried using a weck - cel sponge . one or two drops of both components were instilled simultaneously on the bare sclera near the limbus and just below the free edges of conjunctiva , which were held with forceps . immediately after applying the glue , the conjunctival edges were pressed together with two forceps for two or three minutes to create firm adhesion along the entire length ( fig . excess glue was trimmed with scissors and a pressure patch was applied for 24 hours . postoperatively , antibiotic and corticosteroid eye drops were applied four times daily for four weeks , then twice daily for two more weeks . total surgical time was recorded for each patient and the conjunctival closure time of each wound was recorded later in ten patients from each group . postoperative pain , tearing , and the extent of inflammation were analyzed and compared at one day , one week , three weeks , and six weeks after surgery in both groups . for pain and tearing , patient 's subjective discomfort was graded on a scale from 0-to-3 ( 0 , total comfort ; 1 , minor discomfort ; 2 , moderate discomfort ; 3 , severe discomfort ) . we modified the facial pain scale - revised   to our 0 to 3 scale for patient and parents ease . when a subjective determination of comfort was difficult to obtain in young children , the parents were asked to provide an estimate . using slit - lamp biomicroscope , we graded the conjunctival inflammation in the operated quadrant using a modified conjunctival inflammatory index   ( table 1 ) in which hyperemia , chemosis , and discharge were rated on a 0 to 3 scale ( 0 , none ; 1 , mild ; 2 , moderate ; 3 , severe ) for a maximum possible inflammation score of 9 . conjunctival incision healing was also investigated by measuring the largest gap size perpendicular to the incision line ( in millimeters ) using a slit - lamp beam . these observations were conducted for all eyes , although only the right eyes were used in cases of bilateral surgery . statistical analysis was performed with mann whitney u - test ( spss ; spss inc . , one eye of one male patient in the fibrin group was excluded due to conjunctival wound dehiscence caused by inadvertent removal of the patch one hour after surgery . study subjects included 15 males and 24 females , ranging from two to 62 years of age ( mean , 13.1 years ) . ten patients in the fibrin group and 12 in the suture group received unilateral surgery . one day and one week postoperative , the pain and tearing scores were significantly lower in the fibrin group than in the suture group ( p = 0.000 , respectively ) ( figs . 2 and 3 ) . the mean duration of discomfort was 1.0  0.2 days in the fibrin group and 3.1  1.1 days in the suture group ( p = 0.000 ) . patients in the fibrin group were easily able to open their eyes one day after surgery ; this achievement was not possible until 2.7 days after surgery in the suture group . postoperative pain was significantly decreased in the fibrin group and was sustained for three weeks after surgery . postoperative tearing was also significantly less in the fibrin group during the two weeks after surgery . mean total surgery time was significantly shorter in the fibrin group ( 48  5 minutes ) than in the suture group ( 63  7 minutes ) ( p = 0.000 ) . the mean conjunctival closure time of ten patients in the fibrin group was 3.85  0.9 minutes ( range , 2 to 7 ) , significantly shorter than that of the ten patients in the suture group ( 8.35  0.6 minutes ; range , 7 to 10 ) ( p = 0.000 ) . the inflammation was significantly more severe in the suture group for the first three postoperative weeks ( p = 0.000 , respectively ) ( fig . 4 ) , but the healing of conjunctival gap did not differ between the groups ( fig . three weeks after surgery , conjunctival incisions had successfully attached in all patients ( fig . 6 ) and remained intact throughout the follow - up period . two eyes ( 10.5% ) in the fibrin group developed conjunctival defects greater than 2 mm , but secondary re - epithelization and spontaneous healing occurred within three weeks without additional sutures . all patients in the fibrin group had some prominent conjunctival vascular engorgement at three and six weeks ( p = 0.087 , and 0.000 , respectively ) , but it resolved gradually and spontaneously . no allergic reactions or infections occurred in the postoperative period . the perilimbal conjunctival incision retracted in 26.3% ( 5 / 19 ) of the fibrin group and in 15% ( 3 / 20 ) of the suture group at six weeks . polyglactin 8 - 0 sutures are commonly used but it can cause irritation and discomfort during the early postoperative period and may delay normal life activities ; young children may not even be able to open their eyes . when handling thin , atrophic , weakened , senile , or scarred conjunctiva , suturing may be time - consuming and may involve a risk of tearing . the glue mimics the physiologic coagulation process , so it is biodegradable and aids wound healing without inducing toxic or foreign body reactions . the fibrin clot is reabsorbed during wound healing within days to weeks depending on the surgery , the amount of glue used , and the proteolytic activity of the treated site . first , it is biocompatible , non - toxic , and may be used beneath a superficial covering such as structural filler , as an alternative to sutures , or as a barrier that facilitates epithelial wound healing . second , fibrin glue creates a two - dimensional seal , while sutures only provide a focal seal . third , the coagulation time of fibrin glue can be controlled during surgery by controlling the thrombin concentration , and its rapid coagulation could shorten the operation time . recently fibrin glue has been studied for many ophthalmic uses [ 2 - 11 ] , including scleral closure in cataract surgery and pars plana vitrectomy . after zauberman and hemo   used non - commercial fibrin glue for conjunctival closure in ten recession and resection procedures , biedner and rosenthal   compared fibrin glue and 9 - 0 polyglactin suture for conjunctival closure in strabismus surgery and confirmed suturing caused more discomfort and inflammation during the early postoperative period . however this study was conducted in only six patients and followed - up 2 weeks after surgery . similarly , dadeya and ms   applied fibrin glue to one eye and 6 - 0 vicryl sutures to the other in 19 patients who underwent bilateral symmetrical horizontal muscle recession . these patients reported increased discomfort and inflammation during the early postoperative period due to sutures ( ocular discomfort in 8 of 19 ( 42.1% ) sutured eyes but in no fibrin glued eyes ) . mohan et al .   also concluded that fibrin glue is a better alternative to polyglactin sutures for conjunctival closure following strabismus surgery . all of these studies were conducted during the early postoperative period with few patients . in our study , we compared 8 - 0 polyglactin sutures with commercial fibrin glue using limbal conjunctival incisions over a longer follow - up time , until conjunctival healing was complete . as in usual clinical situations , recession or resection procedures were performed and in order to produce more objective results , we selected one eye from each patient rather than comparing outcomes on both eyes in the same subject . similar to previous reports , fibrin glue prevented early postoperative discomfort and suture - related complications in our study . postoperative pain and tearing were significantly reduced , and patients in the fibrin group were able to return to normal activities the day after surgery without severe discomfort . the healing process of the conjunctiva takes a similar time course to that in suture closure . it is well known that fibrin glue has a lower tensile strength and slower polymerization compared to those of synthetic adhesives . fibrin glue does not permit strong adhesion immediately after surgery because of its low tensile strength but can withstand the force induced by conjunctival wounds during follow - up in our study . spierer et al .   performed reattachments of rabbit extraocular muscles using fibrin and reported that the tensile strength of the fibrin did not overcome the muscle 's contracture in smaller recessions , thus causing posterior displacements of the inserted muscle . the main finding of our study was that the adhesiveness of fibrin glue for conjunctival wound was successful in a manner comparable to 8 - 0 polyglactin sutures . the conjunctiva was well apposed without any dehiscence by one day postoperatively and thereafter in all patients in the fibrin group . krzizok   used beriplast ( beriplast p ; aventis behring , marburg , germany ) for conjunctival closure in 100 eye muscle surgeries , ten scleral buckling procedures , and 20 pars plana vitrectomies and reported effective sutureless surgery . he concluded that fibrin glue was time saving and effective , especially in thin atrophic conjunctiva in adults , but warned of limited use of fibrin sealant in children because of extensive tenon 's fascia . we did not experience extrusion of tenon or conjunctival dehiscence in our study and speculate that the removal of sufficient anterior tenon and the use of a pressure patch may contribute to successful conjunctival reattachment . when using fibrin glue in fornix incision , erbagci and bekir   did not observe any difference between thin adult conjunctiva and thick pulpy conjunctival wounds in children . consistent with other reports [ 14 - 16,28 - 30 ] , the use of fibrin glue in our study diminished conjuctival closure time by approximately 4.5 to 5 minutes , and the duration of surgery was shortened by 72% compared to that of the suture group . using commercial fibrin glue and a dual injector system provides more simple and quick handling of conjunctiva in strabismus surgery . until recently , preparation time , curing time , and cost have precluded the practical use of fibrin glue . now the development of commercial fibrin glue with a dual injector system , reliable serologic tests , and well - established methods for sterilization make it a much more practical application . however , use of fibrin glue may theoretically transmit disease and/ or cause an anaphylactic reaction , although we are unaware of any such cases . in this study , none of the patients showed allergic reaction or viral infection during the follow - up period . although fibrin glue showed successful adhesiveness and tolerance in wound closure , many patients in the fibrin group expressed foreign body sensation and light conjunctival hyperemia during the early healing period . the only adverse postoperative occurrence in this study was some perilimbal conjunctival retraction , which occurred more frequently in the fibrin group but was not significant . we speculate that this reaction was due to the low tensile strength of fibrin glue , which can not endure the traction power of tissue edema or fibrosis during wound healing . even in the conventional limbal approach using sutures , the edges of the conjunctival flap sometimes retracted from the limbus before it formed sufficient adhesions to the underlying sclera , even after proper closure . this retraction was usually well tolerated in most cases , and the thickened conjunctival became smooth and sufficiently flattened as the wound healed . we believe that gluing is more difficult in medial conjunctival wounds , especially when resecting the medial rectus muscle , because of the extensive tenon and muscle bump . a large , randomized , and long - term follow - up study is needed . histopathologic studies concerning the effects of fibrin glue on episclera and conjunctiva in humans as well as the effects of re - operation after gluing will be needed . in conclusion , our results indicate that the use of fibrin glue decreases early postoperative pain and tearing , postoperative inflammation and surgical time , and provides a more comfortable course for conjunctival closure after strabismus surgery . therefore , this procedure should be considered as an alternative to sutures . before application in children with extensive tenon 's capsule , sufficient excision of the anterior tenon is recommended .
purposeto evaluate and compare the efficacy and tolerance of fibrin glue and sutures for closing conjunctival wounds in strabismus surgery.methodsin a prospective trial , we performed strabismus surgery using limbal incisions . 
 conjunctival wounds were closed with fibrin glue in 20 eyes of 20 patients ( fibrin group ) and 8 - 0 polyglactin suture in 20 eyes of 20 patients ( suture group ) . 
 postoperative pain , tearing , and inflammation were compared at 1 day , 1 week , 3 weeks , and 6 weeks after surgery . 
 conjunctival incision healing was also investigated.resultsone day and one week post - operatively , pain and tearing scores were lower in the fibrin group ( p = 0.000 , respectively ) . 
 mean surgery time was significantly shorter in the fibrin ( 48  5 minutes ) than the suture group ( 63  7 minutes ) ( p = 0.000 ) . 
 inflammation was significantly more severe in the suture group until 3 weeks postoperative ( p = 0.000 , respectively ) , but conjunctival healing did not differ between the groups . 
 hyperemia appeared more prominent in the fibrin group 3 and 6 weeks after surgery ( p = 0.087 and 0.000 , respectively ) . 
 two eyes in the fibrin group showed conjunctival gaps of more than 2 mm , which closed spontaneously by three weeks after surgery . 
 no allergic reactions or infections developed.conclusionsfibrin glue proved to be as effective as sutures in closing conjunctival wounds . 
 it provides more comfortable early postoperative courses and might be considered as an alternative to sutures in strabismus surgery .