Therapeutic effects of ganciclovir with different injection methods on experimental retinal necrosis

Objective To observe the therapeutic effects of ganciclovir(GCV)with differentInjection methods on experimental acute retinal necrosis(ARN).Methods The right eyes of 41pigmented rabbits were infected by herpes simplex virus(HSV-1)(COS strain)to establish ARN animalmodel.After 24 and 72 hours,GCV was given by intravitreal injection(10 eyes),intravenous injection(11 eyes)and the intravitreal+intravenous injection(10 eyes);intravitreal injection of GCV anddexamethasone(6 eyes)was also included.Four eyes were not treated as the control.The dosage of GCVin intravitreal and intravenous injection was 800 μg and 5 mg/kg weight,respectively.Retina necrosis wasobserved and the grade was recorded 1-21 days after injection according to the grade standard ofretinopathy.The maximum grades of retinal necrosis in different groups were compared.Results Thegrade of retinal necosis was 3.8 in the control group,and 0.2,0.4,0.8,and 2.2 in intravitreal iniection,intravitrcal+intravenous injection,intravitreal injection with GCV and dexamethasone,and intravenousrejection,respectively,24 hours after the model was set up.The effects of the first 3 groups wereobviously better than the Iast group(P=0.003,0.011,0.045);while the difference among the first 3groups were not significant(P=0.881,0.054,0.107).Seventy-two hours after the mode J was set up,thegrades of retinal necrosis were above 1.4 in 4 groups,and the differences among the 4 groups were notapparent(P=0.214).Conclusions In the animal model of ARN,intravitreal injection with GCV caneffectively decrease the grade of retinal necrosis.The difference among intravitrealinjection,intravitreal+intravenous injection,intravitreal injection with GCV and dexamethasone,and intravenous injection is notsignificant. Key words: Retinal necrosis syndrome,acute/therapy; Ganciclovir/administration & dosage; Animal experimentation