# TI-RADS Calculator

Calculate ACR TI-RADS score for thyroid nodule risk stratification. Get FNA biopsy and follow-up recommendations based on ultrasound features and nodule size.

## What this calculates

The ACR Thyroid Imaging Reporting and Data System (TI-RADS) helps radiologists and clinicians decide whether a thyroid nodule needs a biopsy or just monitoring. Enter the ultrasound characteristics of a thyroid nodule to get its TI-RADS level and the recommended next step.

## Inputs

- **Composition** — options: Cystic or almost completely cystic (0 pts), Spongiform (0 pts), Mixed cystic and solid (1 pt), Solid or almost completely solid (2 pts) — Internal structure of the nodule on ultrasound
- **Echogenicity** — options: Anechoic (0 pts), Hyperechoic or isoechoic (1 pt), Hypoechoic (2 pts), Very hypoechoic (3 pts) — Echogenicity compared to surrounding thyroid tissue
- **Shape** — options: Wider-than-tall (0 pts), Taller-than-wide (3 pts) — Measured on transverse image
- **Margin** — options: Smooth (0 pts), Ill-defined (0 pts), Lobulated or irregular (2 pts), Extra-thyroidal extension (3 pts) — Edge characteristics of the nodule
- **Echogenic Foci** — options: None or large comet-tail artifacts (0 pts), Macrocalcifications (1 pt), Peripheral (rim) calcifications (2 pts), Punctate echogenic foci (3 pts) — Bright spots within the nodule
- **Largest Nodule Dimension** (cm) — min 0.1, max 15 — Maximum diameter of the nodule in centimeters

## Outputs

- **Total TI-RADS Points** — Sum of points across all five ultrasound categories
- **ACR TI-RADS Level** — formatted as text — TI-RADS classification (TR1 through TR5)
- **Recommendation** — formatted as text — FNA or follow-up recommendation based on level and size

## Details

ACR TI-RADS assigns points based on five ultrasound feature categories: composition, echogenicity, shape, margin, and echogenic foci. The total points map to one of five TI-RADS levels (TR1 through TR5), each carrying a different risk of malignancy and a size-based recommendation for fine needle aspiration (FNA) biopsy or follow-up imaging.

The scoring works like this: each category contributes 0 to 3 points, and the points are summed. TR1 (0 points) means benign, and no further workup is needed. TR2 (2 points) is not suspicious. TR3 (3 points) is mildly suspicious, with FNA suggested only for nodules 2.5 cm or larger. TR4 (4 to 6 points) is moderately suspicious, with FNA at 1.5 cm. TR5 (7 or more points) is highly suspicious, with FNA at 1.0 cm.

Features most associated with malignancy include solid composition, very hypoechoic echogenicity, taller-than-wide shape, irregular margins, and punctate echogenic foci (possible microcalcifications). A purely cystic or spongiform nodule is almost always benign.

This tool is for educational reference. Clinical decisions should always involve a qualified radiologist or endocrinologist who can correlate ultrasound findings with the patient's history.

## Frequently Asked Questions

**Q: What does a TI-RADS score mean?**

A: The TI-RADS score (TR1 through TR5) reflects how suspicious a thyroid nodule looks on ultrasound. TR1 is benign, TR2 is not suspicious, TR3 is mildly suspicious with about a 5% malignancy risk, TR4 is moderately suspicious with a 5-20% risk, and TR5 is highly suspicious with a risk above 20%. Higher scores prompt biopsy at smaller nodule sizes.

**Q: When is a thyroid nodule biopsy (FNA) recommended?**

A: According to ACR TI-RADS guidelines, FNA is recommended for TR3 nodules at 2.5 cm or larger, TR4 nodules at 1.5 cm or larger, and TR5 nodules at 1.0 cm or larger. TR1 and TR2 nodules generally do not require biopsy. Follow-up ultrasound is recommended at smaller size thresholds for TR3, TR4, and TR5 nodules.

**Q: What are punctate echogenic foci?**

A: Punctate echogenic foci are tiny bright spots seen on thyroid ultrasound. They often represent microcalcifications, which are small calcium deposits that can be associated with papillary thyroid carcinoma. They score 3 points in the TI-RADS system. Not every bright dot is a microcalcification, though. Comet-tail artifacts from colloid can look similar but are benign and score 0 points.

**Q: Can a thyroid nodule with a low TI-RADS score still be cancerous?**

A: It is very rare but possible. TI-RADS is a risk stratification tool, not a definitive diagnosis. Purely cystic and spongiform nodules (TR1) have an extremely low malignancy rate (close to 0%). TR2 nodules also carry very low risk. However, clinical context always matters. If there are other concerning findings like lymph node abnormalities, your doctor may recommend further evaluation regardless of the TI-RADS score.

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Source: https://vastcalc.com/calculators/health/tirads
Category: Health & Fitness
Last updated: 2026-04-08