Thyroid Ultrasonography: Much Ado About Nothing? A Provocative Analysis

Thyroid ultrasonography (US) usage has risen significantly over the past two decades, with annual increases of up to 21% in some healthcare systems. This review examines patterns in thyroid US usage, factors driving potential misuse, and strategies to mitigate overuse. While thyroid US provides valuable information on thyroid morphology and structure without radiation exposure, inappropriate use-estimated at 10-50% of exams-leads to adverse consequences, including patient anxiety, unnecessary procedures, and potential overdiagnosis of thyroid cancer. The widespread adoption of US has coincided with increased thyroid cancer diagnoses, yet mortality rates remain unchanged, suggesting overdiagnosis rather than actual disease increase. Clinical guidelines consistently recommend selective US use not for routine evaluation of thyroid dysfunction (hyper/hypothyroidism) without palpable abnormalities, but for the anatomical assessment of palpable nodules. For thyroid incidentalomas (ITNs), evidence suggests negligible malignancy risk for nodules < 1 cm, arguing against further investigation. The paper proposes a rational approach to thyroid US, emphasizing that patients with thyroid dysfunction without palpable abnormalities, euthyroid patients without palpable nodules, and patients with subcentimetric ITNs should not undergo thyroid US. Addressing this overutilization requires a better understanding of contributing factors and targeted interventions. By restricting US to appropriate clinical scenarios, healthcare resources can be optimized without compromising patient outcomes, ensuring that rare cases of clinically significant thyroid cancer receive proper diagnosis and treatment.