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606 matching questions · page 1 of 51
Symmetric FDG uptake in the supraclavicular & paraspinal fat on a cold day.
Physiological
ReasoningBrown adipose tissue — classic symmetric physiological FDG uptake; warming/beta-blockade reduces it.
Intense, symmetric salivary and lacrimal gland uptake on ⁶⁸Ga-PSMA PET.
Physiological
ReasoningSalivary/lacrimal glands physiologically express PSMA — a normal finding, not disease.
Linear tracer activity along both ureters on ⁶⁸Ga-PSMA PET.
Physiological
ReasoningUrinary excretion of the tracer — physiological; do not mistake for nodal disease.
Focal ⁶⁸Ga-PSMA uptake near the coeliac axis with no CT correlate.
Benign mimic
ReasoningCoeliac (and other sympathetic) ganglia take up PSMA — a benign mimic of a nodal metastasis.
Photopenic defect with surrounding streak next to a metallic hip prosthesis.
Artefact
ReasoningAttenuation-correction / metal artefact — check the non-attenuation-corrected images.
Apparent lung-base uptake that shifts position between AC and non-AC images.
Artefact
ReasoningRespiratory misregistration artefact between PET and CT — not a true lesion.
Intense diffuse myocardial FDG uptake in a non-fasting patient.
Physiological
ReasoningPhysiological myocardial glucose use when inadequately fasted — prep-dependent, not disease.
Focal intense FDG uptake in the sigmoid colon matching a CT polyp.
Disease
ReasoningFocal colonic FDG warrants colonoscopy — premalignant/malignant until proven otherwise.
On a ⁹⁹ᵐTc-MDP bone scan: uptake in stomach, thyroid and salivary glands.
Artefact
ReasoningFree ⁹⁹ᵐTc-pertechnetate (radiopharmaceutical impurity) — a preparation artefact.
Symmetric bilateral vocal-cord / muscle FDG uptake after the patient talked.
Physiological
ReasoningPhysiological muscle uptake (phonation) — symmetric and activity-related.
Focal uptake at the antecubital injection site with ipsilateral axillary nodes.
Artefact
ReasoningExtravasation artefact — tracer drains to axillary nodes; can mimic disease.
Diffuse increased FDG uptake throughout the thyroid gland.
Benign mimic
ReasoningUsually chronic (Hashimoto) thyroiditis — a benign mimic; focal uptake is the one that needs work-up.