NEUROTOLERABILITY OF NONIONIC X-RAY CONTRAST-MEDIA - THE ROLE OF CHEMOTOXICITY

RATIONALE AND OBJECTIVES. Because small quantities of x-ray contrast a gents can cross the blood-brain barrier, the authors evaluate the prop erties that contribute to neurotoxicity. METHODS. The acute toxicity o f various monomer and diner contrast media was assessed after intracer ebroventricular (ICV) injection to mice and intracisternal (ICI) injec tion to rats. RESULTS. In mice, median lethal dose (LD(50)) values for monomer contrast media apart from iohexol were higher than those for dimer contrast media, In rats, iopentol and iopromide were more neurot oxic than all other contrast media, The signs of toxicity for all cont rast media included convulsions, dyspnea, hypoactivity, and sedation, Hypertonic D-mannitol solution was tolerated as well as artificial cer ebrospinal fluid, Neither the hydrophilicity of the molecules nor the physicochemical properties of their solutions explain the toxicities s atisfactorily. CONCLUSIONS. Neurotoxicity of monomer or dimer contrast media depends more on chemical structure characteristics other than h ydrophilicity than an the physicochemical characteristics of their sol utions.