The Role Of Msct In Differential Diagnosis Of Malignant And Benign Thyroid Nodules

ObjectiveTo investigate the CT features that can be reliable to differentiate malignant thyroid nodules from benign ones through the analysis of enhanced CT imaging in patients with thyroid nodules.Materials and methodsThis was a retrospective analysis Patients were scanned with a 64-slice spiral CT machine Siemens Sensation with a scanning range from the mandibular angle to the superior aperture of thorax. Plain and contrast enhanced scans were performed with artery (28s) and venous (60s) phases, and the following reconstructed axial and coronal images were also gotten respectively with reconstructed thickness of 3mm and interval of 3mm. Two radiologists who did not know the pathological results were asked to analyze the images using the picture archiving and communication system (PACS). A total of 86 patients with thyroid nodules underwent neck plain scan and contrast enhanced CT. CT features of thyroid nodules were mainly analyzed including CT value on plain and contrast enhanced CT, and uniformity, boundary definition and growth type of the nodules, and neck lymph node enlargement. The imaging features and pathological results of the thyroid nodules were compared in order to find imaging signs that could differentiate the benign and malignant thyroid nodules. The entry criteria was as follows:solid nodules (less than 10% of cystic component in the total volume of thyroid nodules); the maximum diameter was greater than or equal to 5mm (measurement in histopathological specimens); the largest of the thyroid nodule was choosen; pathological results were consistent with CT findings. Exclusion criteria was as follows:poor quality CT images (for example, heavy clavicle artifact or contrast artifact influenced the image quality); entire calcification nodules; poor consistency between pathological and CT findings. A total of 83 patients were enrolled in the study. Further logistic regression analysis was used to evaluate the relationship between benign and malignant thyroid nodules and every CT findings. The final results were showed with OR and corresponding 95% confidence interval, P value of Wald detection. SPSS 20.0 statistical software was used for data processing and analysis.ResultsA total of 83 patients with included 72 females and 11 males with an average age of 51.4±10.6 years.83 thyroid nodules were found including 35 malignant nodules and 48 benign nodules which were confirmed by pathology. Logistic regression analysis showed that contrast enhanced CT value and uniformity of thyroid nodule, boundary definition and growth type of the nodules, and neck lymph node enlargement had statistical significance in differential diagnosis of thyroid nodules (P < 0.05). In all factors, thyroid nodule boundary definition and growth type were the most valuable in identifying the benign and malignant thyroid nodules. CT value and uniformity of thyroid nodule on plain CT had no statistical significance in differential diagnosis of thyroid nodules (P>0.05).ConclusionCT enhanced scanning is helpful in differentiating benign and malignant thyroid nodules including some contrast enhanced CT parameters as the CT value, uniformity, boundary definition and growth type of the nodules, and neck lymph node enlargement. Homogeneous hypodensity, fuzzy boundaries, and infiltrative growth on enhanced CT, accompanied by lymphadenopathy can be regarded as a possibility of malignant thyroid nodules.