HYDROXYPROPYLMETHYLCELLULOSE AND SODIUM HYALORUNATE IN ADJUSTABLE STRABISMUS SURGERY

The efficacy of hydroxypropylmethylcellulose and sodium hyaluronate as adjuncts during adjustable strabismus surgery was evaluated experimen tally. Fifteen randomized NZA rabbits underwent a bilateral 4-mm reces sion of the superior rectus followed by a 0.05 mt injection of submusc ular hydroxypropylmethylcellulose 2% (HPMC) in one eye and sodium hyal uronate 1% (Healon) in the other eye. Five additional rabbits (10 eyes ), used as controls, underwent the same procedure, but no viscoelastic was injected after surgery. The force needed to move the muscle 4 mm toward its original insertion was measured immediately and 24 hours af ter the operation, using a force gauge, The force needed to adjust the muscles increased 326.0%, 98%, and 124.7%, respectively in the contro l, Healon and HPMC groups (p<0.001). No significant difference was fou nd between the two viscoelastic substances. Histologic evaluation of t he operation sites disclosed similar inflammation in both controls and viscoelastic groups (p = .5960).