Thyroid Incidental Nodules — ACR Management Guidelines
ACR-recommended management algorithm for incidentally detected thyroid nodules on CT, MRI, ultrasound, and FDG-PET. Age-stratified size thresholds with flowcharts.
Key points
- Suspicious features (irregular margins, microcalcifications, extrathyroidal extension) → thyroid ultrasound regardless of size or age
- No suspicious features, age <35 yr → thyroid US if nodule ≥1 cm
- No suspicious features, age ≥35 yr → thyroid US if nodule ≥1.5 cm
- Limited life expectancy or significant comorbidities → no further evaluation, even if size criteria met
- Diffuse FDG uptake on PET → thyroid function tests (likely thyroiditis); imaging follow-up not routinely required
- Focal FDG uptake → malignancy risk ~30–35%; thyroid US in general population
Full reference
Age-stratified flowcharts with CT/MRI, ultrasound, and FDG-PET algorithms
Complete flowcharts, decision trees, and tables — available in RadCall alongside case logging, wRVU tracking, and 99+ additional guides.