Do Iodinated Contrast Agents Affect Prognosis in Acute Experimental Cerebral Ischemia?

Abstract

We studied the effects of ionic and non-ionic iodinated contrast agents in acute cerebral ischemia on infarction volume, neurological performance, and mortality in a rat model of middle cerebral artery (MCA) occlusion. We induced focal cerebral ischemia in 64 rats using an endovascular occlusion technique of the MCA. Four hours after MCA occlusion, 16 animals received sodium iothalamate (588 mg iodine/kg), 16 animals received iopromide as single bolus (518 mg iodine/kg) and 16 animals as double bolus (1036 mg iodine/kg). Sixteen animals received equivolumetric (1.4 ml/kg) saline (control group). Neurological score and body weight were recorded every 8 hours. Twenty-four hours after vessel occlusion all animals were sacrificed and their brains stained with 2,3,5 triphenyl-tetrazolium-chloride (TTC) to assess infarction size. The normal and the double clinical dose of iopromide did not affect infarction volume and neurological performance. Sodium iothalamate caused an increase in infarction volume and worsening of the neuroscore compared with the control group (p<0.05). Mortality in the iothalamate group was 25%, compared to 12.5% in the control group and 6.25% in the iopromide groups, respectively. Our results suggest that bolus injection of the non-ionic iopromide in clinically relevant doses does not significantly affect infarction volume and clinical symptoms of cerebral ischemia. Non-ionic contrast agents should be preferred to ionic contrast agents during the acute stage of cerebral ischemia.