In some cases of primary hyperparathyroidism, in particular where neck exploration has been unsuccessful, an alternative to surgical therapy may be desirable. We studied the acute and chronic metabolic effects of attempted angiographic destruction by angiographic contrast infusion of solitary parathyroid adenomas in 18 patients with symptomatic disease. Fourteen patients had failed prior surgery; 4 patients had not undergone prior surgery but were extremely high surgical risks. Cervical adenomas were present in 17 of 18 subjects; mediastinal adenoma in 1 of 18. Sixteen patients underwent selective parathyroid venous catheterization, which facilitated subsequent arteriographic localization. Selective arteriographic localization and attempted angiographic ablation were performed in all subjects with standard contrast, renografin-60. Laboratory studies, including serum calcium and PTH, were frequently performed before and after attempted angiographic parathyroid ablation. In all patients serum calcium fell to normal or subnormal levels within 48 h of attempted ablation. Prolonged follow-up (mean, 35.1 months) revealed that ablation was curative in 12 of 18 (sustained normocalcemia) and partially effective in 1 of 18 patients. For the entire group serum calcium fell from 3.14 +/- 0.07 at presentation to 2.42 +/- 0.07 mmol/L at the end of follow-up (or before surgery in unsuccessful cases; P less than 0.001). In 4 of 5 failed cases hypercalcemia recurred within 2 weeks. All 5 failed cases underwent curative surgery, aided by accurate localization achieved during angiographic procedure. Several transient complications and 1 case of permanent hypoparathyroidism were noted. We conclude that angiographic ablation of cervical parathyroid adenomas can be considered as an extension of diagnostic angiographic procedures in selected cases of primary hyperparathyroidism who have failed prior surgery of possibly in rare cases where surgery is contraindicated.