Ultrasound Assessment of Thyroid Nodules Using TIRADS and Its Association with Cytology Results: A Cross-Sectional Observational Study

Background: Thyroid nodules are common diseases both in clinical and radiologic practice and most are non-cancerous. Thyroid Imaging Reporting and Data System (TI-RADS) is a grading system that helps to stratify the malignancy risk and assists in choosing a nodule for fine-needle aspiration cytology. The objective is to evaluate thyroid nodules by ultrasound-based TI-RADS, and to investigate its association with cytological results. Material and Methods: It was a cross-sectional observational study that involved 50 thyroid nodule patients who underwent evaluation in the department of Surgery at Tripura Santiniketan Medical College, West Tripura, Tripura, India between the period August, 2024 – January, 2025. High-resolution ultrasonography of the thyroid was performed in all patients. The nodules were classified by the composition, echogenicity, margins, and shape, along with the presence or absence of echogenic foci, to TI-RADS. The Bethesda system was used to classify the FNA specimens. An appropriate statistical test was used to evaluate the association between the results of the cytology and the TI-RADS category. Results: The average age of the population studied was 42.6 ± 12.8 years, with 72.0% of the cases being female. Solitary thyroid nodules were found in 68.0%. The highest percentage were found to have been in the category TR4, followed by TR3 and TR5. The cytology diagnostics showed benign findings in 68.0%, indeterminate findings in 14.0%, suspicious cytology in 6.0% and malignant cytology in 12.0%. The 2 positive outcomes of cytology (suspicious and malignant cytology) correlated with the higher TRADs categories and were most frequently seen with nodules assigned to a TR5 category. Statistically, there was a correlation between the cytology category and TI-RADS category. Conclusion: There was a significant correlation between Ultrasound based TI-RADS and cytology result, and the Ultrasound-based TI-RADS was useful for risk stratification of thyroid nodules. Excellent correlation of higher TI-RADS was found with suspicious or malignant cytology results.

Keywords: From the thyroid standpoint, keywords are thyroid nodule, TI-RADS, ultrasonography and fine-needle aspiration cytology, Bethesda system and thyroid malignancy.