Chemomyectomy Effect of Doxorubicin and Verapamil on Orbicularis Oculi in Rabbit

ABSTRACT

Doxorubicin has characteristic chemomyectomy effect of the eyelid without disturbing other eyelid structures, but the major side effect of doxorubicin is the potential for eyelid skin injury as a result of the drug's toxicity in both animal and clinical studies. Verapamil may be used to reduce the dose of doxorubicin and the number of injections that would amplify the toxic effects of doxorubicin. This study was performed to determine whether there is an increase in the toxic effect of the doxorubicin as a result of verapamil pretreatment of the muscle. After 0.5mg, 1.0mg, and 2.0mg doxorubicin was injected in lower eyelids of each group, and equal dose of doxorubicin was injected fo11owing 1.0mg of verapamil injection in lower eyelid of each group, muscle cell loss were measured by light microscopy and side effect was observed. In verapamil and doxorubicin injection group, there was significant differences in the amount of preseptal muscle and even in the pretarsal muscle than the doxorubicin injection group in all doxorubicin doses. Verapamil, injected with a range of doses of doxorubicin, caused suhstantia11y increased muscle loss in the eyelid, compared with injection of doxorubicin alone. Skin ulceration, entropion or ectropion were not visible. Clinically, verapamil cotreatment might be useful to decrease the dose of doxorubicin injected and/or the total number of injections.