Adrenal adenomas: characteristic hyperintense rim sign on fat-saturated spin-echo MR images

Radiology. 1994 Oct;193(1):247-50. doi: 10.1148/radiology.193.1.8090900.


Purpose: To determine whether adrenal adenomas can be differentiated from metastases on fat-saturated magnetic resonance (MR) images.

Materials and methods: Twenty-eight adrenal adenomas and 20 metastatic lesions were imaged at 1.5 T by means of fat-saturated T1- and T2-weighted and gadolinium-enhanced T1-weighted sequences. The authors evaluated visually whether structures of high signal intensity (hyperintense rim sign) could be observed in the outer margin of the adrenal masses.

Results: Twenty-six of 28 adrenal adenomas revealed the hyperintense rim sign on at least one kind of fat-saturated image, compared with only one of 20 metastases. The sensitivity of the hyperintense rim sign as suggestive of adrenal adenoma was 92%, specificity was 95%, and overall accuracy was 94%.

Conclusion: The hyperintense rim sign is characteristic of adrenal adenomas. Thus, adrenal adenomas can be differentiated from metastases by means of this new imaging sign on fat-saturated MR images.

MeSH terms

  • Adrenal Cortex Neoplasms / diagnosis*
  • Adrenal Cortex Neoplasms / epidemiology
  • Adrenal Gland Neoplasms / diagnosis*
  • Adrenal Gland Neoplasms / epidemiology
  • Adrenal Gland Neoplasms / secondary*
  • Adrenal Glands / pathology*
  • Adrenocortical Adenoma / diagnosis*
  • Adrenocortical Adenoma / epidemiology
  • Diagnosis, Differential
  • Female
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Observer Variation
  • Sensitivity and Specificity