How ACR TI-RADS scoring works
TI-RADS is additive. A nodule is assessed in five categories, each category contributes points, and the total decides the TR level. There is no single feature that determines the outcome on its own.
Four of the five categories are pick-one: you choose the single description that fits. Echogenic foci is the exception — it is the only category where more than one finding can be present at once, and the points for each are summed.
| Category | Finding | Points |
|---|---|---|
| Composition | Cystic or almost completely cystic | 0 |
| Spongiform | 0 | |
| Mixed cystic and solid | 1 | |
| Solid or almost completely solid | 2 | |
| Echogenicity | Anechoic | 0 |
| Hyperechoic or isoechoic | 1 | |
| Hypoechoic | 2 | |
| Very hypoechoic | 3 | |
| Shape | Wider-than-tall | 0 |
| Taller-than-wide | 3 | |
| Margin | Smooth | 0 |
| Ill-defined | 0 | |
| Lobulated or irregular | 2 | |
| Extra-thyroidal extension | 3 | |
| Echogenic foci (additive) | None or large comet-tail artefacts | 0 |
| Macrocalcifications | 1 | |
| Peripheral (rim) calcifications | 2 | |
| Punctate echogenic foci | 3 |
From points to TR level
The total maps onto five levels. Note that the published chart labels TR2 as "2 points", but the bands are continuous: a nodule scoring a single point is TR2, not TR1. Only a nodule scoring zero is TR1.
| Total points | Level | Descriptor |
|---|---|---|
| 0 | TR1 | Benign |
| 1–2 | TR2 | Not suspicious |
| 3 | TR3 | Mildly suspicious |
| 4–6 | TR4 | Moderately suspicious |
| 7 or more | TR5 | Highly suspicious |
Size thresholds for aspiration and follow-up
The TR level alone does not decide management — it sets two size thresholds, and the nodule’s maximum diameter decides which applies. Above the aspiration threshold, recommend fine-needle aspiration. Between the two thresholds, recommend ultrasound surveillance. Below both, neither is indicated.
TR1 and TR2 nodules need neither aspiration nor imaging follow-up at any size. This is the part most often got wrong in a report: a large but entirely benign-appearing nodule does not earn surveillance because it is large.
| Level | Aspirate at | Follow at | Follow-up schedule |
|---|---|---|---|
| TR1 | — | — | None |
| TR2 | — | — | None |
| TR3 | 2.5 cm | 1.5 cm | 1, 3 and 5 years |
| TR4 | 1.5 cm | 1.0 cm | 1, 2, 3 and 5 years |
| TR5 | 1.0 cm | 0.5 cm | Annually for 5 years |
Where TI-RADS scoring most often goes wrong
Echogenic foci are treated like the other categories. They are not. A nodule with both macrocalcification and punctate echogenic foci scores 1 + 3 = 4 points from that category alone, which is enough to carry it from TR3 to TR4 on its own.
Spongiform is scored as solid. Spongiform composition scores zero, the same as a simple cyst, and it is a specific appearance: aggregated microcystic spaces occupying more than half the nodule. It is not a synonym for heterogeneous.
Undetermined features are skipped. Each category has a defined default when the finding cannot be assessed — composition scores 2, echogenicity scores 1, margin scores 0. Leaving a category out understates the total.
Very hypoechoic is judged against the wrong reference. The comparison is the adjacent strap muscle, not the surrounding thyroid parenchyma.
The largest nodule is scored and the rest are ignored. Each nodule is scored independently; the one that determines management is the one with the highest TR level, which is not reliably the biggest.
Frequently asked questions
What is ACR TI-RADS?
The American College of Radiology Thyroid Imaging Reporting and Data System, published in 2017. It standardises how a thyroid nodule seen on ultrasound is described and scored, so that a category carries the same meaning between readers and between centres, and so that the decision to aspirate follows a stated rule rather than individual preference.
How is a TI-RADS score calculated?
Assess the nodule in five categories — composition, echogenicity, shape, margin and echogenic foci — and add the points. Four categories are pick-one. Echogenic foci is additive, so every type present contributes its points. The total maps to a level: 0 is TR1, 1 to 2 is TR2, 3 is TR3, 4 to 6 is TR4, and 7 or more is TR5.
What do the TI-RADS levels mean?
TR1 is benign, TR2 not suspicious, TR3 mildly suspicious, TR4 moderately suspicious and TR5 highly suspicious. The level is a description of imaging appearance and an estimate of risk; it is not a diagnosis, and it does not by itself decide management until the nodule size is applied to it.
When does a thyroid nodule need fine-needle aspiration?
TR3 nodules at 2.5 cm or larger, TR4 at 1.5 cm or larger, and TR5 at 1.0 cm or larger. TR1 and TR2 nodules are not aspirated at any size.
When does a nodule need ultrasound follow-up instead?
When it sits between the two thresholds for its level: TR3 from 1.5 cm, TR4 from 1.0 cm, TR5 from 0.5 cm. Follow-up runs at 1, 3 and 5 years for TR3, at 1, 2, 3 and 5 years for TR4, and annually for 5 years for TR5.
Do TR1 and TR2 nodules ever need follow-up?
Not under ACR TI-RADS, at any size. Size raises neither category above its threshold because neither has one.
How are multiple thyroid nodules handled?
Score each nodule separately on its own features. Management follows the nodule with the highest TR level, which is not necessarily the largest. The ACR white paper also suggests limiting reporting to the four most suspicious nodules.
Can TI-RADS be applied to CT, MRI or PET findings?
No. TI-RADS descriptors are ultrasound descriptors. A nodule found incidentally on another modality needs dedicated thyroid ultrasound before it can be scored.
Does this calculator send anything anywhere?
No. It runs entirely in your browser, makes no network requests, stores nothing and has no analytics. It works offline and from a USB stick on a reporting workstation.
Source
Tessler FN, Middleton WD, Grant EG, 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.
This tool is an independent implementation and is not affiliated with or endorsed by the American College of Radiology or any other body named here. It is intended for qualified healthcare professionals, and it supports a reporting decision rather than making one. The published guideline remains normative.