EH 5_2015

F1 F2 F3 F4 EUROPEAN HOSPITAL  Vol 24 Issue 5/15 20 ULTRASOUND How good is 2-D shear-wave elasto- graphy for the diagnosis of cirrho- sis of the liver, and does it offer any advantages compared to tran- sient elastography? This was the subject of a study carried out at the University Hospital Frankfurt am Main under joint leadership of statistics expert Prof. Dr. Eva Hermann and gastroenterologist Prof. Dr. Mireen Friedrich-Rust. The study was first introduced in Vienna at the 50th Annual Congress of the European Association for the Study of the Liver (EASL) in April this year and is due to be published shortly. It comprises clinical data of 1,340 patients in 13 centres. 120 patients for this meta-analysis came from the University Hospital Frankfurt itself. For each patient, the histological grade of fibrosis deter- mined by the liver biopsy was corre- lated with the elastography results, as Prof. Dr. Mireen Friedrich-Rust, Consultant at the Centre for Internal Medicine, reports. 972 patients out of the overall group were assessed at the highest level. ‘There’s also the issue of time. Examinations of the pleura and lungs require a lot of time spent with both the patient and the technology. Ultrasound is particularly suitable to diagnose pleural effusion and pneumothorax, and for clinical monitoring of pneumonia, and spe- cifically to monitor pneumonia in chil- dren. For pleural effusions, ultrasound is the method of choice for diagnosis and for US-guided puncture, and is far superior to ‘blind’ puncture of pleural effusions. ‘This, of course, does not mean that conventional X-rays or CT are bad; however, they require a medical indi- cation and their use must be justified, based on the medical radiation protec- tion guidelines.’ What about chest X-rays, as used to detect tuberculosis (TB)? ‘We need to differentiate between dif- ferent types of infection, here. If you are healthy, middle aged, and working and you suddenly develop a cough, fever and phlegm, chances are that the diagnosis is CAP, i.e. community- with transient elastography in addi- tion to the 2-D shear-wave elas- tography. The patient population consisted of patients with Hepatitis C (470), Hepatitis B (420), non- alcoholic fatty liver disease (172) and other types of liver disease. No fibrosis, or only mild fibrosis, was diagnosed in 40.8% of patients; 19.3% had a moderate fibrosis, 14% severe fibrosis and 26% were suffer- ing from cirrhosis of the liver. Better differentiation in early stages Based on current data, 2-D shear- wave elastography achieves a better differentiation, particularly in the early stages of fibrosis, interprets Friedrich-Rust. Her explanation is that 2-D shear-wave elastography facilitates the examination of a larg- er area and sends multiple shear waves into the tissue. ‘The region of interest is larger, and particularly in the early stages of fibrosis the histo- logical changes are often distributed inhomogeneously,’ explains the con- sultant. If only a smaller, random area is selected the results are less precise. The present meta-analysis confirms a slight superiority of the 2-D shear-wave elastography across the entire range of patients and stages of fibrosis as long as the qual- ity criteria of transient elastography are disregarded, says Friedrich-Rust. If the quality criteria are taken into consideration the superiority for the diagnosis of a moderate liver fibro- sis persists, and this is frequently the threshold used to decide on whether treatment should begin. Friedrich-Rust phrases the sum- mary of the results seen so far very carefully ‘The results of the study definitely confirm that 2-D shear- wave elastography is at least as good as transient elastography.’ One advantage for her is the fact that the 2-D shear-wave elastography is integrated into a routine ultrasound scanner, so there is no need for the purchase of additional special- ist equipment which puts pressure on budgets. ‘An ultrasound scanner with this additional tool is a gain for all clinicians.’ In Germany, Austria and Switzerland ultrasound is performed by doctors from different areas of expertise. However, for pulmonary and pleu- ral infections many specialists refer patients to radiologists rather than make their own diagnosis via ultra- sound. One reason is that only a few doctors have expertise in all aspects of ultrasound. A further reason is that ultrasound has its limitations when it comes to lung diseases, explains Professor Gerhard Mostbeck, radiolo- gist at the Wilhelminen Hospital and Otto-Wagner Hospital in Vienna. Asked why so many clinicians refer patients to radiologists to diagnose pulmonary and pleural infections, rather than perform the examina- tions themselves, Professor Gerhard Mostbeck explained: ‘It’s not only knowledge, i.e. theo- retical knowledge that’s required here, but also practical skills and a lot of practical experience with clinical ultrasound. Ultrasound is a great pro- cedure – but it’s of no benefit unless you know a lot about it. Any doctor, be they emergency medics or specialists in lung disease or internal medicine, should be familiar with ultrasound. However, in clinical practice only a small proportion of doctors are actu- ally competent in all aspects of clinical ultrasound, and it’s mostly those who have developed a particular interest in this technology. Ultrasound goes far beyond real-time applications. Nowadays, contrast-enhanced ultra- sound, elastography and other new procedures also facilitate multipara- metric examinations; but, even though all this may be taught over the course of a medical degree, not everyone will become an expert in this technology Using every examination 2-D Shear-wave elastography The advantages of a larger examination area Pulmonary a pleural infec Mireen Friedrich-Rust is a consultant at the Centre for Internal Medicine, University Hospital Frankfurt am Main. Having read medicine in Münster, Heidelberg, New Haven and New York, Professor Friedrich- Rust wrote her habilitation treatise at the Johann Wolfgang Goethe University Frankfurt am Main and was awarded an extracurricular professorship in 2014 Gerhard Mostbeck heads the Institute for Diagnostic and Interventional Radiology at the Wilhelminen Hospital and the Institute for X-ray Diagnostics at the Otto-Wagner Hospital, Vienna. Having qualified as a radiology specialist at the Medical University of Vienna, he wrote his habilitation treatise in 1990 on an ultrasound-related topic. From 2002-2005 he was President of the Austrian Society for Ultrasound in Medicine (ÖGUM) and 2006-2008 he presided over the Austrian Roentgen Society. In 2000 he was presi- dent of the congress of the ultrasound societies of the Dreiländertreffen – the three German-speaking countries in Vienna, and of the WFUMB-EFSUMB and the Dreiländertreffen on Ultrasound in Vienna in 2011, as well as of the ESGAR Annual Meeting in Salzburg in 2014 Liver stiffness measurement with 2-D-ShearWave Elastography. Ultrasound scan of the right chest with pleural effusion, lower lobe consolidation with abscess-forming pneumonia and parapneumonic effusion.

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