ACR TI-RADS
Score a thyroid nodule with ACR TI-RADS: composition, echogenicity, shape, margin and echogenic foci give points, and the total together with nodule size decides between aspiration, follow-up and nothing.
Ultrasound features
Points
7pts
Category
TR5
7 points · TR5 · 14 mm
7 points gives TR5, highly suspicious. The score sums five independent features, so two nodules at the same level can look quite different on ultrasound.
At 14 mm the nodule is at or above the 10 mm aspiration threshold for TR5. Fine-needle aspiration is therefore the indicated next step.
At this level, also describe the cervical nodes. A suspicious node changes management more profoundly than the nodule score itself, and is easily skipped in the rush to characterise the nodule.
The reported probability of malignancy at TR5 is around 35%. If a nodule grows during follow-up by 20% or more in at least two dimensions, with a minimum increase of 2 mm, that alone is reason to escalate management, even while it stays below its aspiration threshold.
TI-RADS grades a single nodule. With multiple nodules, score each separately and act on the highest-scoring one rather than the largest — the most commonly made error here.
How to read the result
The score answers how suspicious the nodule looks; the size answers whether that suspicion is worth acting on now. A TR5 nodule of 6 mm and a TR3 nodule of 30 mm both exist, and they lead to different places.
How the score is built
Points = composition + echogenicity + shape + margin + echogenic foci
The first four categories are exclusive: one choice each. Echogenic foci are additive, so a nodule with both macrocalcifications and punctate foci scores both.
0 points is TR1, 2 points TR2, 3 points TR3, 4 to 6 points TR4, and 7 or more TR5.
The level alone does not decide anything. Only together with the largest diameter does it produce a recommendation.
When to use it
- Reporting a thyroid ultrasound in which one or more nodules need a structured risk category.
- Deciding whether a nodule meets the size threshold for fine-needle aspiration at its risk level.
- Setting a follow-up interval for a nodule that does not yet warrant aspiration.
- Standardising language between readers, where a numeric score travels better than an adjective.
⚠️ Pitfalls
- Score each nodule separately and act on the highest-scoring one, not the largest. Acting on size alone is the commonest error with multinodular glands.
- Echogenic foci are additive while the other four categories are not. Selecting several types of foci is correct; selecting two margins is not.
- Punctate echogenic foci and colloid comet-tail artifacts look alike at low magnification and differ by three points. Zoom in before scoring.
- TI-RADS was developed for adults and does not transfer cleanly to children, nor does it apply to a nodule already known to be malignant.
- The categories describe the nodule, not the patient. A suspicious cervical node or a history of neck irradiation outranks the score.
Frequently asked questions
How is the ACR TI-RADS score calculated?
Assign points for composition, echogenicity, shape and margin, add points for every type of echogenic focus present, and total them. Zero points is TR1, two is TR2, three is TR3, four to six is TR4 and seven or more is TR5.
At what size does a TI-RADS nodule need aspiration?
It depends on the level: 25 mm for TR3, 15 mm for TR4 and 10 mm for TR5. TR1 and TR2 nodules need no aspiration at any size.
When is ultrasound follow-up advised instead?
When the nodule sits below the aspiration threshold but above the follow-up threshold: 15 mm for TR3, 10 mm for TR4 and 5 mm for TR5.
Are echogenic foci really additive?
Yes, and this is the one category where several selections are correct. A nodule with macrocalcifications and punctate echogenic foci scores for both, which is often what pushes it from TR4 into TR5.
Which nodule do I act on when there are several?
The one with the highest score that also meets its size threshold. The largest nodule is frequently not the most suspicious one, and following size alone is how significant nodules get missed.
References
📄Tessler FN, et al. ACR Thyroid Imaging, Reporting and Data System (TI-RADS): White Paper of the ACR TI-RADS Committee. J Am Coll Radiol. 2017;14(5):587–595.
📄Grant EG, et al. Thyroid Ultrasound Reporting Lexicon: White Paper of the ACR Thyroid Imaging, Reporting and Data System Committee. J Am Coll Radiol. 2015;12(12 Pt A):1272–1279.
📄ACR TI-RADS resources.↗This calculator supports clinical judgement and does not replace it. Always check the result against your own measurements and the guideline in force.
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