(0754) Unnecessary Thyroid Ultrasounds in the TI-RADS Era: A Review of Medicare Claims Data

Introduction: American College of Radiology's Thyroid Imaging Reporting and Data System (TI-RADS) was published in 2017 and serves to clarify nodule management based on risk stratification. Based on TI-RADS scores, decisions are made on further management, including no action, follow-up ultrasound (US), or fine-needle aspiration.

Methods: TI-RADS does not recommend US after 5 years. Outpatient hospital Medicare claims data from January 2016 to June 2022 were analyzed for US utilization.

Results: The intervals between surveillance follow-up thyroid US showed peaks at 12 months (132,700 claims), followed by 6 months (54,800 claims), and 2 years (21,700 claims). Most Medicare patients (97%) undergoing thyroid US received between one to four US, with an average of 1.6 claims per person. 67% of the claims were for only one thyroid US. The incidence of malignant thyroid nodules rose with an increasing number of US claims per patient. 56% of patients receiving more than 12 US exhibited thyroid malignancy (n=215), in contrast to only 2% among those who received a single US (n=1,106,300). A total of 25,700 unique patients underwent 6 or more US, and among them, 76.5% were associated with nonmalignant thyroid nodules (n=19,700).

Conclusions: Six-month interval US is not recommended by TI-RADS, though is compatible with American Thyroid Association (ATA) guideline recommendation. The incidence of malignancy in individuals undergoing a single US was lower than anticipated for the general population, suggesting that some patients without a thyroid nodule appropriately did not undergo subsequent US. Patients with benign thyroid nodules receiving six or more thyroid US deviate from TI-RADS and results in an excess Medicare expenditure exceeding $13 million. Limitations include the time interval that began slightly before TI-RADS format was popularized and ATA guidelines have alternate recommendations.