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Nevertheless, MRE offers a number of advantages over ultrasound elastography, such as the ability to make elastograms of parts of the body which ultrasound cannot reach (the brain transcranially and the lungs), as well as its intrinsic: controlled-frequency of vibration, 3D imaging, ability to image both elastic and viscous moduli, and capability to provide elastic anisotropy information (i.e., as a function of the direction of shear wave propagation). Commercial ultrasound elastography has yet to evolve some of these technical capabilities which arguably makes current MRE potentially more accurate and precise than current ultrasound elastography. This may explain why recent comparisons suggest that, although ultrasound and MR elastography both have good accuracy for identifying and staging liver fibrosis, MRE is the more accurate of the two [31; 38; 39; 40; 41]. Nevertheless, they each have technical strengths and limitations; ultrasound elastography may be unreliable in obese patients or where intercostal access is limited, and MRE quality may be poor in patients with substantial iron deposition [41]. The paper on the \"Effect of HCV Core Antigen and RNA Clearance during Therapy with Direct Acting Antivals on Hepatic Stiffness Measured with Shear Wave Elastography in Patients with Chronic Viral Hepatitis\" C showed that liver stiffness significantly declined during and after successful antiviral treatment [42]. So far, liver stiffness monitoring during antiviral therapy has been mostly published using TE. Published data on patients who were treated with direct antiviral agents (DAAs) suggest that liver stiffness declines during treatment in patients with advanced fibrosis [43; 44; 45; 46; 47; 48; 49]. The decline in liver stiffness reflects more the reduction of inflammatory changes of the liver than it does in true fibrosis. The paper \"Interpretation US Elastography in Chronic Hepatitis B with or without Anti-HBV Therapy\" concludes that 2D-SWE (regrettably referred to as ARFI) is a reliable tool for the measurement of liver fibrosis in chronic hepatitis B patients with alanine aminotransferase \(<\)5\(\times\) the upper limit of normal. For those patients under anti-HBV therapy, the optimal timing for SWE analysis will be over 1 to 2.5 years of nucleos(t)ide analogue therapy [50]. The paper \"Shear Wave Elastography Combining with Conventional Grey Scale Ultrasound Improves the Diagnostic Accuracy in Differentiating Benign and Malignant Thyroid Nodules\" tackles the issue of the differential diagnosis of thyroid nodules. In patients with normal thyroid parenchyma, elastography can rule out malignancy with a high level of certainty if the lesion is displayed as soft. A stiff lesion can be either benign or malignant [51]. The same is true for other parenchomatous organs, e.g., the pancreas [52]. \"Non-Invasive Assessment of Hepatic Fibrosis by Elastic Measurement of Liver Using Magnetic Resonance Tagging Images\" is a paper that aims to overcome the disadvantage of MRE mentioned above, i.e., that it normally requires an MR-compatible mechanical vibrator which complicates patient set-up. Multiple locations covering a grid in the liver were tracked using MR tagging during liver displacement that was caused by forced exhalation. Two features were then extracted from the resulting time-varying grid patterns, bending energy and the difference between the spatial Fourier transforms of the grid from one moment to another. These features summarize the overall non-rigid deformation in the liver, both normal and shear strain. The more rigid the liver, the lower the values for both of these types of features. In preliminary testing on 17 normal and 17 abnormal liver cases (6 chronic hepatitis cases and 11 liver cirrhosis cases), with manual intervention in setting grid landmarks for tracking, only one abnormal liver was misclassified as normal by a bivariate linear classifier.