Role of Peak Systolic Velocity of Inferior Thyroid Artery in Differential Diagnosis of Graves' Disease and Hashimoto's Thyroiditis

Background: Thyrotoxicosis is the clinical manifestation of a set of illnesses defined by excessive thyroid hormone action at the tissue level, as a result of excessive thyroid hormone concentrations. The aim of the study: The aim of this study was to evaluate the diagnostic value of ITA-mPSV in differentiating of thyrotoxicosis among Iraqi population. Patients and Methods: From the total 50 cases; 25 patients with proved diagnosis of thyrotoxicosis and 25 patients with thyroiditis were examined in the sonography unit of Rizgary Teaching Hospital, clinical history was taken and physical examination and thyroid function tests were performed for all patients. Results: Thyrotoxicosis patients are younger than thyroiditis patients, but the difference is statistically insignificant. Thyroid volume in thyrotoxicosis (22.14±7.56) is statistically significant higher than thyroiditis (11.92± 4.68). The systolic-diastolic ratio and resistive index of the study groups do not differ significantly. At the cut-off point of (61.50 cm/s); the sensitivity is 96.0%, while the specificity is 92.0%. Positive and negative predictive values are 92.3% and 95.8% respectively with the AUC is (0.962). Conclusion: Measurement of peak systolic velocity of inferior thyroid artery is a useful diagnostic tool for distinguishing between GD and thyroiditis, with high sensitivity and specificity.