Adrenal scintigraphy in primary aldosteronism. Improved visualization after long-term pre-treatment with dexamethasone

Nuklearmedizin. 1981 Apr;20(2):76-81.

Abstract

Dexamethasone-modified adrenal scintigrams were performed on 13 patients with an aldosterone-producing adenoma and on one patient with an aldosterone-producing carcinoma. Adrenal scintigrams using 131I-19-Iodocholesterol were obtained after short pre-treatment with dexamethasone, while 131I-6 beta-Iodomethyl-19-Nor-Cholesterol scintigrams were performed after long-term pre-treatment with dexamethasone during 9-21 days. Using the former procedure the adrenal scintigrams correctly identified the adenoma in 3 of 8 patients, while with the latter procedure the adrenal scintigrams localized the adenomas in 8 out of 9 patients, including 3 patients in whom the former procedure had failed. The adrenal carcinoma was not visualized with 131I-6 beta-Iodomethyl-19-Nor-Cholesterol. Thus, the sensitivity of 131I-19-Iodocholesterol scintigrams to detect aldosterone-producing adenomas was only 37.5%. Uptake of radioactivity in the normal contralateral adrenal gland accounted for the low detection rate. On the other hand, the 131I-6 beta-Iodomethyl-19-Nor-Cholesterol scintigrams, performed after long-term pre-treatment with dexamethasone, had a sensitivity of 89%. It is suggested that long-term pre-treatment with dexamethasone contributed to the improved sensitivity by a more effective suppression of radioactivity uptake in the normal adrenal gland.

MeSH terms

  • 19-Iodocholesterol
  • Adenoma / diagnostic imaging
  • Adolescent
  • Adosterol
  • Adrenal Gland Neoplasms / diagnostic imaging*
  • Adrenal Glands / diagnostic imaging*
  • Adult
  • Dexamethasone*
  • Female
  • Humans
  • Hyperaldosteronism / diagnostic imaging*
  • Iodine Radioisotopes
  • Male
  • Middle Aged
  • Radionuclide Imaging
  • Time Factors

Substances

  • Iodine Radioisotopes
  • 19-Iodocholesterol
  • Adosterol
  • Dexamethasone