The widespread use of ultrasonography has contributed to increased detection of thyroid nodules.
Nodular thyroid disease was classified by different guidelines and it was difficult to determine which nodule was suspicious of malignancy.
TIRADS (Thyroid Imaging Reporting And Data System) is a reporting data system for thyroid lesions,
proposed to standardize the reporting of results of thyroid ultrasound that can be understood by clinicians and also to stratify the risk of malignancy of a lesion based on ultrasound features.
It was introduced by Horvath et al in 2009,
drawing inspiration from “Breast Imaging and Reporting Data System” (BIRADS) of the American College of Radiology and later simplified and modified by Park et al, Kim et al and Russ et al. Using the modified Russ classification,
each nodule was classified into a TIRADS category (1,
2,
3,
4A,
4B and 5) based on the US features.
The following categories of TIRADS were established by Russ et al:
TIRADS 1:Normal thyroid ultrasound
Fig. 1: Transverse sonogram showing normal thyroid gland - TIRADS 1
TIRADS 2:Benign aspects- Simple cyst, Spongiform nodule, White Knight aspect, Isolated macrocalcification and Typical subacute thyroiditis.
Fig. 2: Longitudinal sonogram of thyroid gland showing a simple cyst- TIRADS 2
TIRADS 3:Probably benign aspects- Isoechoic, Hyperechoic
Fig. 3: Transverse sonogram of thyroid showing a well defined isoechoic nodule - TIRADS 3
TIRADS 4A:Low Suspicious aspect- Moderately hypoechoic
Fig. 4: Transverse sonogram of thyroid showing a well defined moderately hypoechoic nodule - TIRADS 4A
TIRADS 4B&5:High Suspicious aspects- Taller than wide shape, Irregular/ microlobulated margins, Microcalcification, Marked hypoechogenecity.
TIRADS 4B: 1/2 signs and no adenopathy
Fig. 5: Longitudinal sonogram of thyroid showing a markedly hypoechoic nodule with microcalcification - TIRADS 4B
TIRADS 5: more than or equal to 3 signs and / or adenopathy
Fig. 6: Transverse sonogram of thyroid showing a taller than wide markedly hypoechoic nodule with microcalcification - TIRADS 5.
Risk of malignancy
TIRADS 2: 0%, TIRADS 3: <5%, TIRADS 4A: 5‐10%, TIRADS 4B: 10‐80, TIRADS 5: >80%.
The purpose of this study is to determine the diagnostic test properties of Russ modified TIRADS in differentiating benign from malignant nodules taking cyto/histopathological diagnosis as gold standard.
Secondly,
to find out the proportion of malignancy in each TIRADS category.