"Parathyroid hormone (PTH) is typically elevated (normal range 10–55 pg/mL), often with raised serum calcium. However, even a “normal” PTH may be inappropriately elevated if calcium is high; values above ~25 pg/mL are generally considered non-suppressed in this context 45."
"internal or central vascularity (~85–97% in primary disease) 29-31"
"adenomas usually show higher ADC values (~1.5–2.0 × 10⁻³ mm²/s) than thyroid or lymph nodes"
"false negatives in small lesions, rapid washout, or low mitochondrial density (e.g. chief cell–predominant adenomas)"
"MRI is not commonly used as a first-line modality due to lower spatial resolution and vulnerability to motion artefact, particularly at the thoracic inlet. It can be useful in selected cases when other imaging is inconclusive or contraindicated, such as localisation of ectopic glands or in reoperative settings."
"Atypical parathyroid adenoma is no longer recommended in the WHO Classification, and has been renamed as a separate clinical entity, atypical parathyroid tumour."
"microvascular Doppler techniques (e.g. SMI or MVFI) can improve detection of slow flow and small feeders 39"
"Ga-68 DOTATATE: somatostatin receptor targeting; occasionally useful in MEN1 or atypical glands 44"
Expected headings
"Variants"
"Greyscale"
"Doppler"
"Additional techniques"
"Scintigraphy"
"PET imaging"
"Many patients are diagnosed asymptomatically through biochemical screening. Symptomatic cases reflect primary hyperparathyroidism and the effects of elevated calcium and parathyroid hormone, including bone pain, fractures, renal calculi, constipation, pancreatitis, and neurocognitive symptoms (e.g. fatigue or poor concentration) 34,35."
"Parathyroid adenomas are usually composed of chief cells, though oxyphil and mixed types occur. Most are solitary (up to 87% 2), well-circumscribed, and oval or bean-shaped; larger lesions may be multilobulated."
"Parathyroid hormone (PTH) is typically elevated (normal range 10–55 pg/mL), often with raised serum calcium. However, even a “normal” PTH may be inappropriately elevated if calcium is high; values above ~25 pg/mL are generally considered non-suppressed in this context 45."
"C-11 methionine: limited availability; niche role 34"
"Ga-68 DOTATATE: somatostatin receptor targeting; occasionally useful in MEN1 or atypical glands 44"
"oesophagus: may mimic a lesion on ultrasound; look for movement, internal gas or mucosal stripe"
"sequestered thyroid tissue: may appear similar; typically shows higher attenuation on non-contrast CT due to iodine"
"ultrasound is typically first-line; 4D CT or sestamibi added if ultrasound is non-localising"
"false negatives in small lesions, rapid washout, or low mitochondrial density (e.g. chief cell–predominant adenomas)"