Side-effects at phlebography with ionized and non-ionized contrast medium.

In two studies 267 consecutive patients with suspected venous thrombosis were examined 125I-fibrinogen uptake test at phebography. In 161 patients meglumine metrizoate (Isopaque Cerebral) and in 106 patients metrizamide (Amipaque) was used as contrast medium. The quality of the examinations was equal in the two groups. During the examinations most of the patients examined with meglumine metrizoate had symptoms from the calf described as a cramp-like pain. Only few of the patients examined with metrizamide had such symptoms. In the two groups 47 patients examined with meglumine metrizoate and 41 examined with metrizamide had normal phlebography as well as initially normal 125I-fibrinogen uptake test. After phlebography, 29 of the patients in the first group had a significant rise in fibrinogen uptake while such a rise was not found in patients from the second group. Rephlebography showed fresh deep vein thrombosis in 7 out of 9 patients examined with meglumine metrizoate indicating that thrombosis could be provoked in as many as about half the patients with this high osmolar contrast medium. We have now used metrizamide in about 400 patients without any side-effects.