A reexamination of the angiotoxicity of superselective injection of DMSO in the swine rete embolization model

BACKGROUND AND PURPOSE: There are a variety of embolization applications fo r nonadhesive, liquid agents. We reevaluated the potential microvascular an giotoxicity of superselective infusions of dimethyl sulfoxide (DMSO) using very long infusion rates in a previously described animal model. METHODS: Twenty-six swine underwent percutaneous femoral puncture for super selective catheterization of the artery of the rete while being continuousl y monitored for ECG and intraarterial pressure. Two volumes (0.5 or 0.8 mL) and three durations (30, 60, and 90 seconds) of superselective infusion of DMSO were used to evaluate the effect of a single-dose rate within an ipsi lateral rete. Contralateral control infusions of normal saline were also ad ministered. Acute hemodynamic and angiographic outcomes were assessed. Afte r recovery, followup angiography and sacrifice were performed at either 10 or 28 days. Brains and retia were harvested for gross and microscopic histo pathologic evaluation. RESULTS: No significant hemodynamic alterations occurred acutely, Twenty-th ree of the 24 infused retia showed variable acute vasospasm that typically was mild to moderate in severity and transient (10 to 20 minutes). Follow-u p angiography at sacrifice always showed normal retial arterial anatomy. No adverse clinical sequelae were noted. Gross inspection of brains showed no evidence of infarction or subarachnoid hemorrhage. Microscopic histopathol ogic examination of retia showed mostly nonspecific changes in both exposed and control samples. Possible causal histotoxicity was seen in four retia (three of four exposed to higher dose rates), in which involvement was limi ted to one to three retial arteries. CONCLUSION: Lower total dose and dose rates of superselective infusion of D MSO into the retial microarterial network resulted in substantially less an giotoxicity than that found in a previous study, as defined by clinical, an giographic, gross, and histopathologic criteria.