SAT465 Spectral Doppler Ultrasound in Thyrotoxicosis, a Valuable Bedside Tool

Disclosure: M. Morkos: None. K. Raju: None. K. Ibrahim: None. Objective: To assess the utility of spectral Doppler ultrasound as a bedside tool in the differentiation of various etiologies of thyrotoxicosis Research and Design Methods: This is a retrospective cross-sectional study of patients diagnosed with thyrotoxicosis at an academic outpatient endocrinology clinic from August 2019 to November 2022. The peak systolic velocities (PSV) were measured using spectral Doppler ultrasound at the superior and inferior thyroid arteries bilaterally. PSV ≥40 cm/sec in at least a single thyroid artery was considered a specific cut-off for Graves’ disease and PSV of peri-nodular artery ≥ 25 cm/sec was considered a specific cut-off for toxic adenoma. Thyroid antibodies (thyroid stimulating immunoglobulin and thyroid receptor antibody) and occasionally thyroid scan were used to confirm the diagnosis. Descriptive statistics, Chi square, and t-test were utilized to describe and compare data. Results: We identified 73 patients who presented for evaluation and management of thyrotoxicosis, mean age ± standard deviation 45.2 ± 16.4 years, 54 (74.0%) were female, 49 (67.1%) Caucasian, 23 (31.5%) African American, and one (1.4%) was Asian. The confirmed diagnoses were 48 (65.8%) Graves’ disease, 13 (17.8%) thyroiditis, 4 (5.5%) toxic adenoma, 4 (5.5%) amiodarone-induced thyroiditis type 2, 1 (1.4%) toxic multinodular goiter, 1 (1.4%) had a normal repeat thyroid function testing, and 2 (2.7%) were unconfirmed. Diagnosis based on the initial assessment including the spectral Doppler was accurate in 65 (89.0%) of the patients and it was conclusive and confirmatory during the initial encounter in 55 (75.3%) of the patients before additional testing. Thyroid scan was obtained in 9 (12.3%) patients. Incorrectly diagnosed patients included Graves’ disease, thyroiditis, toxic adenoma, and unconfirmed diagnoses, two patients each, a total of eight patients. Conclusion: Spectral Doppler ultrasound can be an effective bedside tool in the clinical assessment of thyrotoxicosis. Presentation Date: Saturday, June 17, 2023