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BACKGROUND: Pulmonary tuberculosis (TB) and lung cancer (LC) are common diseases with a high incidence and similar symptoms, which may be misdiagnosed by radiologists, thus delaying the best treatment opportunity for patients. AIM: To develop and validate radiomics methods for distinguishing pulmonary TB from LC based on computed tomography (CT) images. METHODS: We enrolled 478 patients (January 2012 to October 2018), who underwent preoperative CT screening. Radiomics features were extracted and selected from the CT data to establish a logistic regression model. A radiomics nomogram model was constructed, with the receiver operating characteristic, decision and calibration curves plotted to evaluate the discriminative performance. RESULTS: Radiomics features extracted from lesions with 4 mm radial dilation distances outside the lesion showed the best discriminative performance. The radiomics nomogram model exhibited good discrimination, with an area under the curve of 0.914 (sensitivity = 0.890, specificity = 0.796) in the training cohort, and 0.900 (sensitivity = 0.788, specificity = 0.907) in the validation cohort. The decision curve analysis revealed that the constructed nomogram had clinical usefulness. CONCLUSION: These proposed radiomic methods can be used as a noninvasive tool for differentiation of TB and LC based on preoperative CT data.
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<p><b>OBJECTIVE</b>To evaluate the role of contrast-enhancement magnetic resonance imaging (CeMRI) in patients with myocardial infarction (MI).</p><p><b>METHODS</b>There were twenty-three patients enrolled in this study. After dynamic observation, there were 20 patients who were diagnosed as MI. All those patients underwent coronary artery angiography and CeMRI. MRI was performed with a 1.5-T magnet (AVANTO, SIMENS). After tagged images were acquired, the patients received an intravenous bolus of 0.1 mmol/kg Gd-DTPA at a rate of 5 ml/s. A first-pass perfusion scan was acquired simultaneously with a bolus injection. A second bolus of 0.3 mmol/kg Gd-DTPA was given following the first-pass images. Delayed images were acquired 5 minutes after the second bolus by using an inversion-recovery prepared gated fast-gradient echo-pulse sequence.</p><p><b>RESULTS</b>Hypoenhancement was seen in 20 patients at the first-pass perfusion at the myocardial infarction site, while hyperenhancement was seen at delayed CeMRI. Myocardial infarction area in delayed CeMRI was 16.58% +/- 9.73%, which was correlated positively with peak CK and cTnT (r = 0.821, P < 0.01 and r = 0.565, P < 0.05), respectively. The ejection fraction (EF) detected by MRI was 0.46 +/- 0.13, while the left ventricular EF (LVEF) detected by left ventriculography was 0.49 +/- 0.16. There was no difference between two parameters.</p><p><b>CONCLUSIONS</b>CeMRI may play an important role in the diagnosis and prognosis of patients with MI.</p>