Conray: A New Cardiovascular and Urographie Contrast Medium

Abstract

Conray is a new highly water-soluble, low-viscosity organic iodide contrast agent manufactured by Mallinckrodt Chemical Works. The generic name for the free acid is iothalamic acid and it has the following chemical structure Iothalamic acid contains 62 per cent iodine. The product is available in two forms: a 60 per cent solution of the N-methylglucamine salt, containing 28 per cent iodine, and an 80 per cent sodium salt solution, containing 48 per cent iodine. The latter solution has a viscosity of 8.4 cps at 37.5° C. The 60 per cent solution is also nonviscid and has been recommended for intravenous pyelography, direct and retrograde aortography, cerebrovascular and peripheral arteriography; whereas the 80 per cent solution was devised for intravenous and selective angiocardiography and aortography (1). This report deals with initial clinical trials in patients who received intravenous injections of Conray, 60 per cent, for urography and arterial injections for peripheral and cerebrovascular arteriography, and injections of Conray, 80 per cent, for intravenous and selective angiocardiography, thoracic and abdominal aortography, and nephrotomography. Method of Study Beginning on June 21, 1961, 102 consecutive patients were injected with the 80 per cent Conray solution. Their ages ranged from three weeks to ninety-four years. Another 206 patients were studied after receiving the 60 per cent compound. The latter series consisted of 198 patients who were given 30 ml. of the medium intravenously for urinary tract studies and 8 who had percutaneous arterial puncture for peripheral vascular and carotid-vertebral arteriography. Intravenous angiocardiography, usually via a percutaneously inserted 12-gauge (Robb-Steinberg) special stopcock unit, was performed 62 times in 41 patients, the dosage varying from 1 ml. per kilogram of body weight in infants and children to 50 ml. for adults. A single injection for simultaneous biplane studies was made in 22 instances, 5 patients had 2 injections, and 2 received a third injection. Twelve patients, because they were overweight or had unusually dilated or hypertrophied cardiovascular systems owing to heart failure, aortic aneurysm, or multiple valvular disease, received one-half of the total dose of the contrast agent (total dosage, 1 ml. per kilogram body weight). This was divided equally between two syringes for simultaneous rapid injection intravenously for biplane angiocardiography. Of the total of 62 injections, 8 were made with the Gidlund mechanical pressure syringe via a catheter inserted into the cardiac chambers or venae cavae. Nephrotomography, devised for visualization of the parenchyma of the kidney in order to distinguish renal tumors from cysts, was done in 23 patients (2). The nephrotomographic technic, except for one instance in which a single injection of 50 ml.