Abstract:

Background and purpose: At present, color Doppler ultrasound scoring and radionuclide imaging are two important imaging methods for diagnosing thyroid nodules, but their checking principle is different. Which method is better? Or combining them will be the best method for diagnosing thyroid nodules? This study aimed to compare the value of ^99mTcO₄^- combined with ^99mTc-methoxyisobutylisonitrile (MIBI) imaging, ultrasound scoring method and ultrasound scoring method+^99mTcO₄^-+^99mTc-MIBI imaging in diagnosis of thyroid nodules. Methods: The results of ultrasound scoring method and ^99mTcO₄^- combined with ^99mTc-MIBI imaging were compared in 50 patients with 54 thyroid nodules, and then compared with pathological findings. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the methods were calculated. Results: A total of 54 thyroid nodules were found pathologically including 20 malignant and 34 benign nodules. The sensitivity, specificity, accuracy, PPV and NPV of ^99mTcO₄^- combined with ^99mTc-MIBI imaging were 80.00% (16/20), 70.59% (24/34), 74.07% (40/54), 61.54% (16/26), 85.71% (24/28), re-spectively. Those of ultrasound scoring method were 80.00% (16/20), 88.24% (30/34), 85.16% (46/54), 80.00% (16/20), 88.24% (30/34), respectively. And those of ultrasound scoring method+^99mTcO₄^-+^99mTc-MIBI imaging were 100.00% (20/20), 64.71% (22/34), 77.78% (42/54), 62.50% (20/32), 100.00% (22/22), respectively. The sensitivity of ultrasound scoring method+^99mTcO₄^-+^99mTc-MIBI imaging was higher than ultrasound scoring method or ^99mTcO₄^-+^99mTc-MIBI imaging along (100.00% vs 80.00%, 100.00% vs 80.00%, χ^２ value was 4.444 4 and 4.444 4, P value was 0.035 0 and 0.035 0, respectively). The specificity of ultrasound scoring method was higher than those of two methods combined together (88.24% vs 64.71%, χ^２ value was 5.230 8, P value was 0.022 2). However, no factorial negative thyroid nodule was found by ultrasound scoring method+^99mTcO₄^-+^99mTc-MIBI imaging. Conclusion: Ultrasound scoring method+^99mTcO₄^-+^99mTc-MIBI imaging can offer comprehensive diagnosis of thyroid nodules from their structure and function to avoid missed diagnosis.

Key words: Thyroid nodule, Radionuclide imaging, Technetium, Ultrasonography, Scoring