ABSTRACT
<p><b>OBJECTIVE</b>To explore the application of color Doppler ultrasound in examining hypothyroidism among radiation-exposed workers.</p><p><b>METHODS</b>A total of 181 radiation-exposed workers who had clinical and laboratorial diagnoses of hypothyroidism were divided into X-ray diagnosis group, interventional radiology group, and radiotherapy group. Another 62 healthy people who underwent physical examinations were used as control group. All cases underwent color Doppler ultrasound; thyroid function, sonograms, and blood flow characteristics were analyzed.</p><p><b>RESULTS</b>In the X-ray diagnosis group, interventional radiology group, and radiotherapy group, significant differences in the levels of free thyroxine and thyroid-stimulating hormone were found across workers with different lengths of service (P < 0.05). In the X-ray diagnosis group, interventional radiology group, and radiotherapy group, the percentages of individuals having uneven internal echo intensity among clinical hypothyroidism cases were higher than the percentages among subclinical hypothyroidism cases (P < 0.05). The X-ray diagnosis group, interventional radiology group, and radiotherapy group had significantly higher constituent ratios of grade II and III blood flow signals than the control group (P < 0.05). The peak systolic velocity of the superior thyroid artery (V(max)) was significantly higher in the X-ray diagnosis group, interventional radiology group, and radiotherapy group than in the control group (P < 0.05); in each group, Vmax was significantly higher in clinical hypothyroidism cases than in subclinical hypothyroidism cases (P < 0.05).</p><p><b>CONCLUSION</b>As a simple, non-invasive, and economic examination, color Doppler ultrasound has been demonstrated as a valuable method for evaluating occupational hypothyroidism and holds promise for clinical application.</p>