CT SCAN ABDOMEN ADRENAL ADENOMA PROTOCOL, in Visit Clinic

An adrenal CT protocol is a dedicated abdominal CT to characterize adrenal lesions: a non-contrast scan to measure baseline attenuation (adenoma often ≤10 HU), followed by contrast-enhanced corticomedullary (~30–40 s) and portal venous (~60–70 s) phases, with a delayed scan at 10–15 minutes to calculate absolute (>60%) or relative (>40%) washout. Patient prep: fasting, check renal function/allergies; manage metformin per renal status.

On CT, adrenal adenoma is suggested by noncontrast attenuation ≤10 Hounsfield units (lipid-rich). Indeterminate lesions (>10 HU) undergo contrast-enhanced washout: absolute washout ≥60% or relative washout ≥40% indicates adenoma. Additional supportive features: size <4 cm, homogeneous internal texture, smooth margins, absence of necrosis or irregular calcification, and stability on interval imaging.

Non-contrast CT is the best initial imaging for suspected adrenal adenomas — low attenuation (<10 Hounsfield units) indicates a lipid-rich adenoma. Indeterminate lesions are further evaluated with adrenal CT washout protocols or MRI with chemical-shift imaging (loss of signal on out-of-phase images). PET/CT may be used to distinguish benign from malignant lesions when imaging remains inconclusive.

Yes. A standard abdominal CT (especially with contrast and thin slices) typically visualizes both adrenal glands and can detect enlargement, masses, calcification, or hemorrhage. Very small lesions (<1 cm) may be missed, and indeterminate findings often require a dedicated adrenal CT protocol, delayed contrast phases, MRI, or biochemical testing to determine functionality and malignancy risk.

For incidental, benign‑appearing, non‑functioning adrenal adenomas, repeat imaging once at 6–12 months; if size and appearance are stable, no routine further imaging is usually required. Lesions with suspicious features, growth, or those >4 cm need earlier reassessment and consideration of surgery. Also have baseline and periodic hormonal testing (eg, cortisol) guided by a specialist.

Yes. Routine CT can miss small or atypical adrenal tumors, especially lesions under about 1 cm, lipid-poor adenomas, or masses obscured by artifacts or nearby structures. Dedicated adrenal CT protocols, contrast enhancement, MRI or PET and biochemical testing improve detection and characterization. If clinical or biochemical suspicion remains, repeat or alternative imaging and endocrine evaluation are recommended.