TI-RADS is the Thyroid imaging reporting and data system (TI-RADS).
TI-RADS was first proposed by Horvath et al. in 2009. This classification system is based on the American College of Radiology breast imaging reporting and data system (BI-RADS). It regroups ultrasound presentations specific to thyroid nodules and classifies them into TI-RADS categories 1-6 according to their malignancy.
There are no unified TI-RADS criteria at home and abroad, and different scholars have established their own evaluation systems.
Horvath et al. linked the FNAB findings of nodules with defined ultrasound staging to produce the TI-RADS classification (TI-RADS categories 1-6 for general thyroid pathology and TI-RADS categories 2-6 for nodules) . The following classifications were established.
TI-RADS category 1: normal thyroid.
TI-RADS category 2: benign (malignancy rate 0) ;
TI-RADS category 3: benign nodules possible (malignancy rate < 5%);
TI-RADS category 4: suspicious nodules, category 4 can be divided into 4a (malignancy rate 5%-10%) and 4b (malignancy rate 10%-80%);
TI-RADS Category 5: Possible malignant nodules (malignancy rate >80%);
TI-RADS category 6: typing includes biopsy-proven malignant nodules.
Park et al. summarized 12 thyroid ultrasonographic features and classified thyroid nodules into the following 6 categories based on them.
TUS category 0: no nodules.
TUS category 1: highly suggestive of benign (malignancy rate 0-7%);
TUS category 2: Probably benign (8%-23%);
TUS category 3: indeterminate (24%-50%);
TUS category 4: probably malignant (51%-90%);
TUS category 5: highly suggestive of malignancy (91%-100%).
Kwak et al. summarized five characteristics of malignant thyroid nodules and established the following classification with reference to the BI-RADS classification system for the degree of risk of malignancy.
TI-RADS category 1: negative (without any abnormality) (malignancy rate 0).
TI-RADS category 2: confirmed benign lesions (malignancy rate 0)
TI-RADS category 3: (no suspicious ultrasound presentation) (malignancy rate 1.7%)
TI-RADS category 4.
4a (1 suspicious ultrasound) (malignancy rate of 3.3%), 4b (2 suspicious ultrasound)
4b (2 suspicious ultrasound findings) (malignancy rate of 9.2%), 4c (3 or 4 suspicious ultrasound findings)
4c (3 or 4 suspicious ultrasound findings) (malignancy rate 44.4-72.4%).
TI-RADS category 5: (5 suspicious ultrasound presentations) (malignancy rate 87.5%).
Some units also use.
Class 0: no abnormalities seen on ultrasound in clinically suspected cases, additional tests are needed.
Grade 1: Negative, with normal size and echogenicity of the gland, no nodules, cysts or calcifications.
Grade 2: benign with 0% risk of malignancy, all requiring clinical follow-up.
Grade 3: Probably benign with a risk of malignancy of <2%, puncture biopsy may be required.
Grade 4: The probable percentage of malignancy is 5 to 50% need to combine with clinical diagnosis!
Grade 5: Suggests the highest likelihood of cancer, <95%
Grade 6: Cytologically detectable cancer. Diagnosis of cancer is confirmed!
Grading of thyroid nodules.
Grade 1: Regularly shaped round or oval echoless nodules with no internal blood flow signal. Most commonly seen in thyroid cysts and thyroid adenomas with intracapsular hemorrhage.
Grade 2: Regularly shaped cystic-solid mixed echogenic nodules with blood flow in the solid portion. Most commonly seen in follicular adenomas and adenomatous nodules.
Grade 3: Regularly shaped homogeneous solid echogenic nodules, sometimes with microcalcifications in the perineurium or nodules and abundant internal blood flow. Most commonly seen in follicular adenomas, adenomatous nodules, and differentiated carcinomas.
Grade 4: Irregularly shaped solid echogenic nodules, sometimes microcalcifications can be seen in the perineurium or nodules, with abundant internal blood flow. Mostly seen in differentiated carcinoma.
Grade 5: Solid echogenic nodules with irregular shape and extra-glandular infiltration, sometimes microcalcifications can be seen in the peritoneum or nodules, with abundant internal blood flow. Most often seen in differentiated carcinoma. Signs of carcinoma in thyroid nodules on ultrasound include: lack of halo sign; solid hypoechoic; echogenic heterogeneity; irregular margins; microcalcifications; extraglandular infiltration; and high internal blood flow.