Strabismus surgeries using n-butyl-2-cyanoacrylate and 6-0 vicryl suture material were performed in 16 albino rabbits. Both eyes of 16 rabbits were used. The superior and inferior rectus muscles were recessed and resected 5 mm. In 12 rabbits, n-butyl-2-cyanoacrylate was used and those rabbits were divided into 3 groups, each group (4 rabbits, 8 eyes) was sacrificed 1, 2, and 3 weeks after operation respectively. The eyes were enucleated to examine the tensile strength and pathologic findings of the attached area. In 4 rabbits, 6-0 vicryl suture material was used as a control group in this study. This group was sacrificed and examined 3 weeks following the operation. In the cyanoacrylate groups, there were statistically significant differences and a chronologically increasing tendency of tensile strength between groups. Between the cyanoacrylate and the suture material group at 3 weeks post operation, there was no statistically significant differences in the tensile strength. Pathelogicallyr extraocular muscle bundles revealed patchy areas of interstitial inflammatory infiltration and fibrosis in the cyanoacrylate groups. Capillary telangiectasia and muscle fiber regeneration were commonly observed. The findings in specimens 3 weeks after operation revealed rather mild changes, suggesting healed lesions. In the suture material group, mild inflammatory reactions were found.
Animals ; Enbucrilate/*therapeutic use ; Rabbits ; Strabismus/pathology/*surgery ; Tensile Strength

To find out whether the cryotherapy for the treatment of the retinopathy of prematurity (ROP) causes structural changes of the extraocular muscle (EOM), and also whether the changes are related with the occurrence of strabismus. To examine the acute stage change, we conducted a transconjunctival cryotherapy around the superior rectus muscle of a rabbit and resected it 0, 3, 7, 14, and 28 days after the cryotherapy. In observing chronic changes, we first categorized patients who had an esotropia surgery into groups, one of which combined prematurity and cryotherapy and one group affected by prematurity but without having had cryotherapy. Then we compared the change of EOM with that of a fullterm infant group. In a rabbit, edema, acute inflammatory cells and a large amount of degenerated muscle fibers were observed immediately after the cryotherapy and on the 3rd day. On the 7th day, regenerated muscle fibers were observed and on the 14th day, the inflammatory cells decreased and the amount of regenerated muscle fiber increased. On the 28th day, abnormal findings were not observed any more and the muscle was found to be normal. When chronic changes of EOM in human on 1 1/2 to 8 1/2 years after cryotherapy, there were no abnormal findings observed in three groups. From the study, we can infer that cryotherapy can cause acute inflammation and necrosis of muscle fiber but such an acute change will improve and does not result in structural change in the long term. Therefore, the occurrence of strabismus in patients with ROP is considered to be attributable to reasons other than injury of EOM.
Animal ; Child ; Child, Preschool ; Cryotherapy/*adverse effects ; Human ; Infant ; Infant, Newborn ; Oculomotor Muscles/*surgery ; Rabbits ; Retinopathy of Prematurity/*pathology/*surgery ; Strabismus/*etiology

Extraocular muscle imbalance and diplopia after retina surgery have been previously reported, but the etiology is still controversial. In order to better understand the cause of strabismus after retinal surgery, the authors retrospectively studied 30 patients with persistent strabismus following retinal surgery and combined the result about seven patients of strabismus after retinal surgery in the previous report. Results showed multiple etiologies for the strabismus. Causes of strabismus included fat adherence syndrome (14 patients), non-specific restrictive adhesion (11), displacement of superior oblique tendon (2), scleral explant interfering with ocular motility (1), lost or slipped muscle with adhesion (2), sensory strabismus (2), macular pucker causing ectopic fovea (2), and previous strabismus before the retinal surgery (3). Knowledge of the varieties of abnormalities that can cause strabismus and diplopia will help both the retina and strabismus surgeon prevent and treat strabismus after retinal surgery.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Child, Preschool ; Diplopia/etiology ; Humans ; Middle Aged ; Oculomotor Muscles/pathology ; *Postoperative Complications ; Retina/*surgery ; Retinal Diseases/*surgery ; Retrospective Studies ; Strabismus/*etiology

In adjustable strabismus surgery, a satisfactory final result would be achieved with delayed adjustment. However, the postoperative adhesions following strabismus surgery make delayed adjustment impossible. We evaluated the efficacy of mitomycin C in reducing the severity of postoperative adhesions following strabismus surgery and in delaying the time adjustment after surgery. Experimental rabbits underwent a hang-back recession procedure in the superior rectus muscle. A topical application of mitomycin C was made between the conjunctiva and the sclera for 5 minutes during the operation. We then studied the possible time of delayed adjustment and estimated the minimal forces required for the adjustment. The topical application of 0.1 mg/ml mitomycin C between the conjunctiva and sclera allowed for a 2-week delayed adjustment after surgery, and 0.2 mg/ml mitomycin C prevented the adhesions between these tissues and the muscle 5 weeks after surgery. These results suggest that topical mitomycin C may enhance the success rate of strabismus surgery with delayed adjustment and reduce postoperative adhesions.
Administration, Topical ; Animals ; Chemotherapy, Adjuvant ; Conjunctiva/drug effects ; Mitomycin/administration & dosage/*pharmacology ; Oculomotor Muscles/drug effects/pathology/*surgery ; Ophthalmic Solutions ; Postoperative Complications/prevention & control ; Rabbits ; Sclera/drug effects ; Strabismus/drug therapy/pathology/*surgery ; Suture Techniques ; Tissue Adhesions/prevention & control

An animal experiment was done to evaluate the efficacy of tissue coating with sodium hyaluronic acid and subconjunctival injection of triamcinolone acetate in reducing the severity of postoperative adhesions following strabismus surgery. Experimental animals underwent a mild traumatic surgical procedure in one superior rectus muscle and a severe traumatic surgical procedure in the other superior rectus muscle. Each group was divided into control group, sodium hyaluronate coating group and triamcinolone acetonide injection group. Grading the severity of adhesions through surgical exploration of operative sites and histological comparison after 4 weeks revealed a significant reduction of postoperative adhesions in sodium hyaluronate group compared with control group under conditions of severe surgical trauma. But triamcinolone groups have no significant differences compared with control groups by statistical analysis. Tissue protection afforded by sodium hyaluronate may lead to an effective method which minimizes the surgical trauma to the tissues and reduces the postsurgical adhesions following strabismus surgery.
Animals ; Eye Diseases/etiology/*prevention & control ; Hyaluronic Acid/administration & dosage/*therapeutic use ; Injections ; Oculomotor Muscles/pathology ; Postoperative Complications/prevention & control ; Rabbits ; Strabismus/*surgery ; Tissue Adhesions/prevention & control ; Triamcinolone Acetonide/administration & dosage/therapeutic use ; Wound Healing

PURPOSE: To evaluate and compare the efficacy and tolerance of fibrin glue and sutures for closing conjunctival wounds in strabismus surgery. METHODS: In 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. RESULTS: One 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. CONCLUSIONS: Fibrin 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.
Adolescent ; Adult ; Child ; Child, Preschool ; Conjunctiva/*surgery ; Fibrin Tissue Adhesive/*therapeutic use ; Humans ; Inflammation/etiology/pathology ; Male ; Middle Aged ; Pain, Postoperative/etiology/physiopathology ; Polyglactin 910 ; Postoperative Period ; Severity of Illness Index ; Strabismus/*surgery ; *Sutures/adverse effects ; Tears/secretion ; Tissue Adhesives/*therapeutic use ; *Wound Closure Techniques/adverse effects ; Young Adult