11C-metomidate PET-CT scanning can identify aldosterone-producing adenomas after unsuccessful lateralisation with CT/MRI and adrenal venous sampling
Primary hyperaldosteronism, characterised by hypertension and hypokalaemia, is a syndrome caused by aldosterone excess most commonly from either a unilateral aldosterone-producing adenoma or bilateral adrenal hyperplasia. Subtype classification can be challenging with cross-sectional imaging and even with interventional radiological techniques such as adrenal venous sampling. Imaging with 11C-metomidate positron emission tomography-computed tomography (PET-CT) is an emerging tool that facilitates functional characterisation and potentially successful surgical intervention of aldosterone-producing adenomas. This technique has highlighted that, although unilateral adenomas and bilateral hyperplasia represent opposite ends of the disease spectrum, a relatively common intermediate phenotype exists of unilateral/bilateral multinodular disease.