Role of dynamic contrast-enhanced and diffusion weighted MRI in evaluation of hepatocellular carcinoma after chemoembolization

Purpose: To assess the role of dynamic contrast- enhanced and diffusion-weighted (DWI) MRI in the evaluation of the response of hepatocellular carcinoma (HCC) after chemoembolization. Patient & method: 30 patients having 40 HCC lesions underwent transcatheter arterial chemoembolization (TACE). Ages ranged between 41 and 76 years. All examinations were performed using Philips 1.5 Tesla MRI (Achieva). Precontrast T1, T2, Dynamic contrast enhanced and respiratory triggered DWI MR images with (b = 50, 400, 800 mm/s). DWI MRI images and Contrast-enhanced MRI images after TACE are assessed to evaluate post treatment response. DWI was used to create ADC maps and ADC values were calculated looking for a cut off value using the ROC curve. Results: Dynamic MRI had a sensitivity of 94.1%, a specificity of 95.6%, PPV value of 94.1%, NPV of 95.6% and an overall agreement of 95% compared to 82%, 73.9%, 70%, 85% and 77.5% respectively of DWI MRI. The difference between the malignant residual and well ablated groups' ADC variables was statistically significant P value 0.009. Conclusion: Dynamic and diffusion MRI complete each other in assessment of HCC response to therapy, especially in those who cannot properly hold their breath that cause degradation of the dynamic MR quality

Role of ultrasound, color doppler, elastography and micropure imaging in differentiation between benign and malignant thyroid nodules

Purpose: To evaluate the role of ultrasound elastography, Doppler and micropure imaging in the assessment of thyroid nodules, using the pathological analysis as the reference standard. Patients and methods: A prospective study was carried on all patients referred to radio-diagnosis department at Tanta Cancer Centre between November 2015 and November 2016 for evaluation of undiagnosed thyroid nodules. All patients were examined by B-mode ultrasound, color Doppler, micropure imaging and ultrasound elastography. All thyroid nodules were subjected to fine-needle aspiration biopsy. Results: 90 patients (78 women, 12 men) with 159 incompletely diagnosed thyroid nodules. 24 nodules were malignant and 135 nodules were benign, micro calcification was detected by micropure imaging in 40 nodules (29.6%) in the benign thyroid nodules and in 20 nodules (83.3%) in the malignant thyroid nodules (sensitivity 83.3%, specificity 70.4%, and accuracy 84.9%). Color flow Doppler (type III) with marked intranodular and absent or slight perinodular blood flow, was detected in 19 malignant nodules, with sensitivity 79.2%, specificity 95.6%, and the overall accuracy rate was 88.7%. The predictivity of ultrasound elastographic score measurement has high sensitivity 87.5%, and specificity 91.1%, Strain elastography cutoff value for malignant nodules was 2.7 (Sensitivity 83.3% and specificity 91.1%). Conclusion: Elastography and micropure imaging technique are useful imaging modalities to detect the nature of thyroid nodules. In combination with Doppler and B-mode sonography, they could give a better assessment for undiagnosed thyroid nodules. Keywords: Thyroid nodules, Ultrasound, Micropure, Doppler, Elastograph