Herniography: comparison of morbidity and image quality after use of high and low osmolality contrast media.

The morbidity and image quality after administration of three different contrast media were compared in 229 patients referred for herniography. Sixty patients received metrizoate 150 mg I/ml, 92 received metrizoate 200 mg I/ml, and 77 patients, ioxaglate 200 mg I/ml. Patient discomfort was single-blindedly assessed based on an arbitrary verbal rating scale. The number of patients with pain increased with the osmolality of the contrast media. Metrizoate 200 induced pain in 57% of the patients, metrizoate caused pain in 39%, and ioxaglate 200 in 18%. Hernia patients who received metrizoate 200 had pain significantly more often (72%) than patients without hernia (45%). Seven patients, predominantly young men, had a vasovagal reaction associated with the administration of contrast media. The image quality was sufficient after all injections of 200 mg I/ml. The results indicate that low osmolality contrast media with an iodine concentration of about 200 mg I/ml are well suited for herniography.