I am a hepatologist working at The University of Padua, in Northern Italy (near Milan). I'm conducting the research on liver elastography- assessing diffuse liver disease using elastography for almost 20 years.
We started first with the FibroScan®- a dedicated device that assesses the stiffness of the liver while using an ultrasound equipment were available. I started doing research in this case; we use the limb biopsy as the reference standard to assess the accuracy of the method. We found that elastography was a very accurate method for detecting and staging liver fibrosis. Currently elastography is used as a reliable substitute for liver biopsy in several clinicals, scenarios and guidelines.
The World Federation (Forza Medicine and Biology) of Societies for ultrasound medicine and Biology have given all the information we needed about how to perform elastography, and how it can be used not only for staging liver fibrosis, but also for evaluating the outcome of patients affected with diffuse liver disease. Just a few months ago, we completed the guidelines and updated to the guidelines for assessing the liver fibrosis with Shearwave elastography with the guidelines of the World Federation of for ultrasound in medicine and biology. Several studies have been published on hundred of studies using Shearwave for diffuse liver disease.
Cytosis is assessed with another method that is not elastography. There are other algorithms, however, patients with cytosis are the majority of patients with diffuse liver disease. We want to assess both the stiffness that is directly related to liver fibrosis and quantifying the amount of fat in the liver.
There are specific algorithms for the quantification of liver fat content, and the majority are based on calculating the attenuation coefficient of the ultrasound beam as it traverses the liver tissue. Stiffness is a different property of the liver tissue. Stiffness assess biomechanical properties of a tissue that is unrelated to the acoustic properties of a tissue.
So the art ultrasound, we may find B mode image that is pretty good, but, uh, the liver may be stiffer than normal, and this is due mostly to liver fibrosis. Even though there are, uh, confounding factors, we are assessing stiffness, stiffness may increase not only for liver fibrosis, but also for the inflammation, for infiltrative disease, for, uh, congestive art disease, and, uh, for, uh, cancer, for, uh, focal liver lesions. Elastography, uh, doesn't have a, um, uh, principle role, uh, mostly used for diffuse liver disease for focal level lesions.
Speaker 1 (05:03):
And to, um, characterize them, uh, we use the contrast, the contrast ultrasound that is, uh, completely different. Uh, at the beginning there were, uh, some studies performed assessing the stiffness of a focal lesions, uh, however they say large overlap between, uh, bine and, and malignant liver lesion. And for that reason, elastography has not a, a, a key role in, uh, assessing, uh, focal lesions. Instead for, uh, diffuse liver disease, uh, elastography is a substitute of biopsy, absolutely, yes. But it's already, uh, used for breast. And in, uh, 2015, the world of federation for, uh, art, ultrasound, medicine, and biology. I mean, 10 years ago, uh, issued guidelines for the use of elastography in, uh, breast disease for, uh, assessing, uh, the lesion, uh, in the breast. And now, um, I believe that this year, uh, the update to the guidelines for the breast graphy will be available.
Speaker 1 (06:27):
So, uh, besides, um, the liver, the breast is the organ that is most studied with using elastography. It's used, it's not as easy to perform as we do for, uh, the liver because, uh, it needs, uh, expertise. And again, if you want more detailed information, uh, there, say a, a worldwide expert in, uh, breast elastography living in the states and working in the states in Ohio. That is, uh, Dr. Richard Barr. And you may, uh, reach him if you want to have more details on the use of breast tractography. Uh, we have an, uh, ultrasound school in, uh, <inaudible> that is, uh, endorsed by the Italian Society for Art, ultrasound Medicine in biology. And, uh, we have a colleagues that, uh, attend the school, uh, for practice. And, uh, uh, they are medical doctors in Italy. We do not have, uh, sonographers as in other countries in, uh, Europe.
Speaker 1 (07:44):
So they attend the school to learn now to perform elastography. And generally we have, uh, between 30 and 50, uh, colleagues, uh, each year. They, uh, follow the activity of the ultrasound, uh, uh, unit for, uh, several months. And they get a diploma, uh, by the, uh, endorse by the, uh, Italian society, uh, for razza in medicine and biology. Then we also, uh, have an <inaudible> school. Theum is the European Federation for Razza in Medicine and Biology, and this is a more advanced school for, uh, leader <inaudible>. And to learn how to, uh, perform and to practice in the, our, uh, department and for photo quantification. And we accept, uh, colleagues from, uh, all over the world. We are the colleagues from, uh, Brazil, Argentina, and, uh, other countries in, uh, Europe. They, uh, attend, um, short course, um, generally three days course to learn how to perform as ultrasound, uh, in ay.