From the Guidelines
Yes, a CT scan of the abdomen and pelvis is an excellent imaging modality to assess the adrenal glands, as it provides detailed cross-sectional images of both adrenal glands, allowing for evaluation of their size, shape, and density. This type of scan is particularly useful in detecting abnormalities such as adenomas, hyperplasia, pheochromocytomas, adrenocortical carcinomas, and metastases, as noted in studies such as 1 and 1. The procedure typically takes about 15-30 minutes and may require oral and/or intravenous contrast depending on the specific clinical question. Patients should fast for 4-6 hours before the scan if contrast is to be used.
Key Considerations
- The adrenal glands are retroperitoneal organs located above each kidney, and CT imaging can detect various abnormalities.
- CT scans offer superior spatial resolution compared to ultrasound and are less expensive and more widely available than MRI.
- The radiation exposure is a consideration but is generally justified when there is clinical suspicion of adrenal pathology.
- For optimal assessment, thin-slice (3-5mm) imaging through the adrenal region is recommended, with both pre-contrast and post-contrast images if appropriate, as suggested by studies like 1 and 1.
Clinical Application
- In clinical practice, a CT scan of the abdomen and pelvis is often used as the initial imaging modality to assess the adrenal glands, especially in patients with a history of malignancy or suspected adrenal pathology, as noted in 1 and 1.
- The use of CT scans in this context is supported by guidelines and studies that highlight its effectiveness in detecting adrenal abnormalities, such as those found in 1 and 1.
- While other imaging modalities like MRI and PET scans may be used in certain situations, CT scans remain a primary choice due to their availability, cost-effectiveness, and diagnostic accuracy, as discussed in 1 and 1.
From the Research
Assessment of Adrenal Glands using CT Scan
- A computed tomography (CT) scan of the abdomen and pelvis can be used to assess the adrenal glands, as it provides exquisite images of the adrenal glands and offers the best initial imaging approach in the evaluation of patients with suspected adrenal disease 2.
- CT scans have the highest sensitivity of all imaging modalities for tumor detection in the adrenal glands, and can assess potential concomitant processes in the surrounding tissues 3.
- Non-contrast enhanced computer tomography (CT) is a modality of choice used for the differential diagnosis of adrenal lesions, allowing the detection of 95% of adrenal masses, and the characterization of most of them 4.
- CT is the imaging procedure of choice for detecting adrenal masses, and can detect or exclude an adrenal mass in a high percentage of cases in patients with biochemical evidence of an adrenal endocrine syndrome 5.
Comparison with Other Imaging Modalities
- Magnetic resonance imaging (MRI) is a good modality for cases in which CT examination cannot determine the character of an adrenal tumour, and can differentiate pheochromocytomas from other adrenal masses on the basis of signal characterization 6, 3.
- Nuclear medicine study with the use of Iodine-131 meta iodobenzylguanidine (MIBG) is helpful in the diagnosis of pheochromocytoma, and provides more specific functional information 6, 4.
- Positron Emission Tomography-Computed Tomography (PET-CT) is considered a useful method in patients with a known malignancy history, and can integrate anatomic and functional information 2, 4.
- Ultrasound has a low sensitivity for the detection of small lesions and is not capable of reliable characterization of visualised masses, but plays an important role in the follow-up of non-hypersecreting adrenal lesions 4.