Adrenal imaging

Computed tomography findings in diseases of the adrenal gland

The adrenal gland is a common site of disease, with an abnormality prevalence as high as 9% in autopsy series. With the increasing use of CT, adrenal lesions are frequently found in the daily practice of radiology and are diagnosed in up to 5% of CT examinations performed for varied reasons. Imaging features on CT can establish a specific diagnosis of many of these lesions, including myelolipoma, hematoma and cysts. Once a diagnostic dilemma, now adenomas can be accurately diagnosed using unenhanced CT, chemical shift magnetic resonance imaging and CT contrast washout analysis. Because the adrenal gland is also a frequent site of metastasis, recent literature has focused on imaging characterization of adrenal masses for differentiation of adenomas from metastases. In patients without known malignancy, most adrenal lesions are benign and a specific diagnosis can now be made on the basis of imaging features. It is important to understand the prevalence of adrenal abnormalities because the gland is a common site of disorders, and the increased use of cross-sectional imaging has increased the frequency of detection of adrenal lesions. The prevalence of disease is important in predicting the risk of malignancy when an adrenal mass is discovered in a patient without known cancer. Detection of adrenal gland diseases has increased substantially with the advent and widespread use of imaging techniques. Although several imaging modalities can be used, CT has a central role in both detection and differential diagnosis of an adrenal lesion. The aim of this article is to review the CT findings of adrenal gland diseases.

Non-invasive, quantitative assessment of the anatomical phenotype of corticotropin-releasing factor-overexpressing mice by MRI

High resolution magnetic resonance imaging (MRI) was applied to quantify alterations in thymus and adrenal volumes, as well as body fat in genetically engineered corticotropin-releasing factor (CRF)-overexpressing mice. When compared to the organs in age-matched wild-type animals, the adrenals in CRF-overexpressing male mice were significantly enlarged and the thymus volume in females was significantly smaller. The fat content was significantly larger in CRF-overexpressing mice. The anatomical alterations observed in the MRI studies were in perfect line with post-mortem data (weights of organs). Furthermore, the observed interstrain differences are in agreement with recently published data on (i) the effect of continuous, intraventricular infusion of CRF in rats and (ii) the presence of atrophic adrenals in CRF-knockout mice. The present studies demonstrate that MRI can provide reliable measures of relatively small structures such as the adrenal glands and the thymus in mice. This makes MRI an attractive, non-terminal tool to monitor in laboratory animals, including transgenic mice, the consequence of continuous stress on relevant organs.