Multiparametric Ultrasound (MPUS) or “the many faces” of ultrasonography

Multiparametric ultrasound (MPUS) or “the many faces” of ultrasonography

Alina Popescu

Department of Gastroenterology and Hepatology, “Victor Babeș” University of Medicine and Pharmacy Timișoara,Romania

Received Accepted

Med Ultrason

2019, Vol. 21, No 4, 369-370

Ultrasound (US) is still seen as a “Cinderella” of the imaging techniques, without taking into considerationthe many advantages of the method. It is a real time, dynamic method, very accessible, rather inexpensive, but (and maybe more important) a non irradiating technique,repeatable and very well accepted by patients. Even if for some pathologies the accuracy of conventional US is not so high (for example the positive diagnosis of focal liver lesions), in other situations it is the best method for the diagnosis (for example gallbladder stones, biliary obstruction).

The major drawbacks of US are considered operator dependence and lack of specificity and accuracy for some diagnoses. On the other hand, with proper training, it is a very good method for orientation in clinical practice and a very good screening method. Because it is well accepted by the patients it is also a good follow up method.

If the drawback of being an operator dependent method can be overcome by training, the lack of accuracy is a disadvantage that is harder to overcome.

One of the criticisms brought to US in the past was the impossibility to characterize the vascularization of different lesions, a feature necessary for the correct diagnosis of the different pathologies. Even if the Doppler techniques are established ultrasound techniques as M and B-mode, the lack of possibility to perform a contrast enhanced study, such as for contract enhanced computer tomography (CE-CT) or contrast enhanced magnetic resonance imaging (CE-MRI), limits the possibility of characterization of different lesions detected by US, and on account of these limits the accuracy of the technique.

The development of new applications in US in the last period has improved the position of this imaging technique in the management of different pathologies. The 3D and 4D US but, more importantly, contrast enhanced US (CEUS) and US based elastography techniques, provided the missing data required for a better diagnosis accuracy of US, and created the concept of multiparametric ultrasound (MPUS) [1], a term borrowed from sectional imaging, especially MRI.

There are several examples in the literature of the role of MPUS for the assessment in different pathologies: prostate cancer [2-4], chronic kidney diseases [5], thyroid nodules [6] or parathyroid lesions [7].

I want to bring attention to another organ – the liver, where the role of MPUS is already well known and emphasized also by other authors [8], and more specifically - focal liver lesions. US is an excellent imaging modality for the detection of liver tumors, but it lacks the necessary specificity for a correct positive diagnosis.

The evaluation of a focal liver lesions can be very expensive (CE-CT or CE-MRI), needs time and usually is very stressful for the patients. CEUS changed this, because is an US technique that can be performed in the same session as conventional US: it takes 5 more minutes, and has good accuracy for the characterization of liver tumors [9]. The accuracy increases if we know if the lesion is developed on a cirrhotic or a non-cirrhotic liver [9].

US can answer today also this question, more precisely US based elastography, a technique with a very good accuracy for ruling in or ruling out liver cirrhosis in a very short time (less than 5 minutes) [10]. Elastography of the focal lesion can also be helpful for the diagnosis in some situations. Thus, in a three-step algorithm using MPUS, starting with conventional US, followed by elastography and then CEUS, we can make a complex evaluation of a focal liver lesion in the same session with a very good accuracy for the positive diagnosis.

In conclusion, US is here to remain in the big picture of imaging techniques and should be used, with all its available features, as the first line diagnostic method in many situations.

MRI ELASTO and US ELASTO in Liver Fibrosis

Elastographic US and G I GIST Tumor

Supersonic to debut quantification tools at RSNA 2019.

By AuntMinnie.com staff writers

November 26, 2019 -- Ultrasound equipment manufacturer SuperSonic Imagine will be debuting three new quantitative liver ultrasound applications at the upcoming RSNA 2019 meeting in Chicago.

The first two tools, Att Plus and SSp Plus, are designed to simultaneously quantify ultrasound attenuation in the liver and intrahepatic speed of sound to reflect fat content for detecting and diagnosing hepatic steatosis, according to the vendor.

The third new tool, Vi Plus, works in combination with real-time elasticity imaging to visualize and quantify tissue viscosity. These viscosity assessments provide clinicians with information for tissue characterization.

Liver Health: Three New Ultrasound Markers Enter the U.S. Market

SuperSonic Imagine, a major actor promoting innovation in ultrasound, will introduce a suite of three ultrasound markers for non-invasive assessment of the severity of chronic liver diseases with quantitative results: Att PLUS, SSp PLUS and Vi PLUS. The first two of these tools allow for the simultaneous quantification of ultrasound attenuation in the liver and intrahepatic sound speed, reflecting fat content, an essential criterion for the detection and diagnosis of hepatic steatosis. Coupled with elasticity imaging in real time, the third one, Vi PLUS, makes it possible to visualise and quantify tissue viscosity, providing clinicians with important information for tissue characterisation.

“Liver diseases including non-alcoholic steatohepatitis (NASH) linked to conditions like diabetes and obesity affect millions of Americans and have become an important public health concern in the space of just a few years. We are very proud to present the fruits of our expertise in liver health — the series of three non-invasive liver markers — for the first time in the United States. All the more so as these markers have just received 510(k) clearance from the FDA. Following the acquisition of SuperSonic Imagine by Hologic, we are also going to present many shared sessions dedicated to women's health,” concludes Michèle Lesieur, the CEO of SuperSonic Imagine.

ULTRASOUND THALAMOTOMY MAY HELP TREAT ESSENTIAL TREMOR.

By AuntMinnie.com staff writers

November 21, 2019 -- A treatment that uses ultrasound may be effective in relieving symptoms of essential tremor by targeting the affected area of the brain, according to a study published online November 20 in Neurology. The treatment, called focused ultrasound thalamotomy, essentially destroys the area of the brain causing the tremor.

More than 7 million people in the U.S. have essential tremor, according to the American Academy of Neurology. Currently, the most common treatment for the disorder when patients don't respond to medication is deep brain stimulation, a procedure that involves incisions and insertion of electrodes or probes into the patient's brain. Ultrasound thalamotomy would offer a less invasive treatment option and remains effective for approximately three years. It does, however, cause an irreversible brain lesion.

For the study, 56 patients received ultrasound thalamotomy and 20 received a fake treatment. The research team measured hand tremors, level of disability, and quality of life at the commencement of the study and after six months, one year, two years, and three years. By the three-year mark, the researchers noted a 50% improvement in hand tremors, a 56% improvement in disability, and a 42% improvement in quality of life.

While senior author Dr. Casey Halpern of Stanford University did note some limitations of the study, he concluded that "this treatment should be considered as a safe and effective option" for those living with essential tremor.