Effect of fibrin glue as an adjuvant to hang-back surgery

Abstract

Background: The hang-back surgery is a useful technique in the field of strabismus surgery. The aim of this study is to determine the stabilizing effects of fibrin glue as an adjuvant to hang-back surgery.

Materials and methods: Four (4)-mm hang-back recessions of the superior rectus muscle was performed in 32 eyes of 16 rabbits. Only in the left eye of the 16 rabbits, fibrin glue was applied between the recessed muscle bed and the sclera at the end of hang-back surgery (fibrin glue group). After 6 weeks, we compared the stability of the recessed rectus muscle between the fibrin glue group and the control group by evaluating the displacement of the muscle.

Results: The frequency of stable insertion of the recessed muscle at the intended site was greater in the fibrin glue group (9 eyes) compared to the control group (3 eyes) (p=0.028). In the control group, 5 eyes showed anterior displacement and 8 eyes showed posterior displacement and in the fibrin glue group, 1 eye showed anterior displacement, and 6 eyes showed posterior displacement. Anterior displacement was more common in the control group (6.3% Vs 31.3%). The control group and the fibrin glue group showed similar histological findings on microscopic examination.

Conclusions: Fibrin glue is effective in stabilizing the new rectus muscle insertion and decreasing the displacement in the hang-back surgery.

Figure 1

Fibrin glue (Greenplast kit®). Human fibrinogen concentrate and thrombin were loaded into each syringe and were simultaneously injected through Y-piece and application needle.

Figure 2

Gross appearance immediately after (A,B) and 6 weeks after (C,D) surgery. Conventional hang-back recession was performed on the superior rectus muscle of the both eyes, and one side was remained without any manipulation (A) and fibrin glue was applied between superior rectus muscle bed and the sclera only in the left eye (B) . After 6 weeks, the distance between the original and the new insertion site was grossly measured (C,D).

Figure 3

Histological appearance 6 weeks after the surgery. The right eye with conventional hang-back recession (A) and the left eye with fibrin glue after hang-back recession (B) showed similar findings. Rectus muscle at the insertion site was separated from the scleral surface and surrounded by fibrous tissue which was attached to the sclera. Inflammatory cells were rarely seen. Red blood cells were found more frequently in the right eye. Bar = 200 μm.