Adrenal hyperplasia

Preliminary Diagnosis: Adrenal Hyperplasia

I. What imaging technique is first-line for this diagnosis?

CT scanning without intravenous contrast and without oral contrast

II. Describe the advantages and disadvantages of this technique for diagnosis of adrenal hyperplasia.

Advantages

• CT scan without contrast is able to visualize adrenal hyperplasia.

• CT scans are relatively quick imaging procedures that require minimal patient cooperation and are less susceptible to motion artifact.

Disadvantages

• Exposure to ionizing radiation

• Rarely, hyperplastic adrenal glands may appear nodular and mimic solitary or multiple adenomas.

• Metastatic diease, tuberculosis, and histoplasmosis may have a similar appearance.

• Half of biochemically hyperplastic glands may appear normal.

III. What are the contraindications for the first-line imaging technique?

• CT scanning is contraindicated in pregnant patients, especially within the first two trimesters.

IV. What alternative imaging techniques are available?

• Ultrasound

• MRI

V. Describe the advantages and disadvantages of the alternative techniques for diagnosis of adrenal hyperplasia.

Ultrasound

Advantages

• May demonstrate bilateral diffuse enlargement or multiple bilateral small nodules

• Relatively inexpensive

• Portable imaging modality

• Does not use ionizing radiation

• For pregnant patients, it is the first choice of imaging.

Disadvantages

• Technically challenging in the adult

• Limited evaluation in obese patients

MRI

Advantages

• MRI without contrast is able to identify bilateral adrenal hyperplasia.

• May be able to characterize adrenal adenoma

• There is no ionizing radiation exposure.

Disadvantages

• Expensive

• Time consuming

• Requires marked patient cooperation to limit motion artifact

VI. What are the contraindications for the alternative imaging techniques?

Ultrasound

• No significant contraindications exist.

MRI

• Hazards exist for patients who have ferromagnetic devices implanted in their bodies.