ICUS Weekly News Monitor 4-20-2018


1.Science Daily, Detailed images of tumor vasculature - Medical engineering, April 18,2018

News-Medical.net, By tracking individual microbubbles, high-resolution images can be taken with conventional ultrasound scanners, April 18, 2018

2.Journal of the American Society of Echocardiography, Clinical Use of Ultrasound Enhancing Agents; Contrast-Enhanced Echocardiography Has the Greatest Impact in Patients with Reduced Ejection Fractions, March, 2018 Authors: Hang Zhao MD, et al

Science Daily

Detailed images of tumor vasculature - Medical engineering

News-Medical.net

By tracking individual microbubbles, high-resolution images can be taken with conventional ultrasound scanners.

April 18, 2018

Ruhr-University Bochum. "Detailed images of tumor vasculature: Medical engineering." ScienceDaily, 18 April 2018. <www.sciencedaily.com/releases/2018/04/180418111652.htm>.

Summary:

Thanks to a new method of analyzing ultrasound images, conventional scanners can be used for generating high-res images of blood vessels in tumors. This approach makes it easier to distinguish between different types of tumors, and it facilitates the tracking of the progress and success of chemotherapy.

The new technology has been developed jointly by teams headed by Prof Dr Georg Schmitz at the Chair for Medical Engineering at Ruhr-Universität Bochum and by Prof Dr Fabian Kiessling at the Institute for Experimental Molecular Imaging at the University Hospital Aachen. They published their report in the journal Nature Communications from April 18, 2018.

Monitoring microbubbles on their path through the body

The new technology called "Motion Model Ultrasound Localization Microscopy" is based on contrast medium-enhanced ultrasound images. Microbubbles are administered to patients as contrast agents: gas bubbles no larger than one micrometre that travel through the body in the bloodstream. In ultrasound images, they appear as shapeless white blobs. "Once the centre of each of these blobs has been identified, it's possible to determine the location of individual bubbles," explains Georg Schmitz.

Each bubble is given a name

Using algorithms originally developed for radar technology, the research team successfully monitored the motion of individual microbubbles. "We are currently attempting to teach the computer something that our eyes are able to do: namely read movement in a sequence of images in which a dot appears in different locations," says Schmitz. To this end, the researchers gave each bubble a name. Thus, they were able to track their paths through the vascular system and count them in the process.

Resolution much higher than mere image resolution

Subsequently, fine vascular networks can be reconstructed based on the motion of the bubbles. The direction and speed of the blood flow can likewise be recorded. The resolution of the images is greatly enhanced: experts refer to the technique as super-resolution imaging.

"In the publication, we demonstrated that the synthesis of morphological and functional parameters considerably facilitates the differentiation between tumour types," explains Fabian Kiessling. In the course of their project, they tested the technique in three model cases, including in human subjects. In collaboration with Prof Dr Elmar Stickeler from the Clinic for Gynaecology and Obstetrics at the University Hospital Aachen, the researchers successfully identified how tumour vessels responded to chemotherapy in breast cancer patients.

Monitoring therapy effects

"One reason why this is important is because new therapy approaches aim at manipulating the vascular system of tumours, in order to enhance the therapeutic effect by increasing the concentration of drugs in the tumours," says Fabian Kiessling. One of these approaches is so-called sonoporation. Here, tumours are treated with ultrasound in order to render the vascular walls more permeable to active substances.

"The advantage of our approach is that it can be performed with conventional ultrasound scanners, which have a low frame frequency, with sometimes as few as 15 images per second," points out Georg Schmitz. The research teams have already filed an application for a follow-up project, in the course of which they intend to test the method in large-scale clinical studies.

 
 
 
 
 
 

Journal of the American Society of Echocardiography

Volume 31, Issue 3, March 2018, Pages 289-296

 https://doi.org/10.1016/j.echo.2017.09.003

Clinical Use of Ultrasound Enhancing Agents; Contrast-Enhanced Echocardiography Has the Greatest Impact in Patients with Reduced Ejection Fractions

Authors: Hang Zhao MD a, b, Rupal O'Quinn MD a, Marietta Ambrose MD a, Dinesh Jagasia MD a, Bonnie Ky MD a, Joyce Wald DO a, Victor A. Ferrari MD a, James N. Kirkpatrick MD, FASE c, Yuchi Han MD, MMSc, FASE a

aCardiovascular Division, Department of Medicine, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, Pennsylvania, bDepartment of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China,  cCardiovascular Division, Department of Medicine, University of Washington School of Medicine, Seattle, Washington

Highlights

•Contrast use in patients with suboptimal images affects patient care, especially in patients who have reduced precontrast estimated LVEF.

•The impact of contrast use is seen more significantly in patients with HF, cardiomyopathy, and arrhythmias.

•The impact of contrast is not influenced by the results of prior studies, whether outpatient or inpatient, or whether the patient has a defibrillator or a pacemaker.

Background

Contrast-enhanced echocardiography (CE) helps to improve image quality in patients with suboptimal acoustic windows. Despite current recommendations, contrast use remains low. The aim of this study was to identify populations that would benefit more from contrast use.

Methods

A total of 176 subjects (137 men; mean age, 60.8 ± 13.7 years) with technically difficult transthoracic echocardiographic studies who received clinically indicated intravenous contrast were prospectively studied. The impact on clinical decision making (including alterations in medical therapy, referral, imaging, or clinical procedures) was evaluated.

Results

The use of CE enabled biplane left ventricular (LV) ejection fraction measurement in 97.2% of studies and the interpretation of regional wall motion in 95% of studies. CE allowed definitive assessment of the presence or absence of LV thrombus in 99% of the cases. In the 174 patients whose ordering physicians could be reached at the time of image interpretation, changes in management occurred in 51% of subjects. There was no difference in the proportion of management changes between inpatients and outpatients (60.0% vs 48.1%, P = .225). Subjects with heart failure, cardiomyopathy, and arrhythmia had a higher proportion of changes (61.4% vs 44.2% [P = .031], 62.5% vs 45.0% [P = .028], and 72.0% vs 47.7% [P = .030], respectively). The proportion of management change after CE increased as pre-CE estimated ejection fraction decreased. Logistic regression showed that pre-CE estimated LV ejection fraction < 50% was the only significant predictor of change of management after contrast (P = .004).

Conclusions

The use of CE has a significant impact on clinical decision making in patients with suboptimal acoustic windows, especially in those with depressed pre-CE LV ejection fractions.

ICUS Sponsors

ICUS gratefully acknowledges its 2017 sponsors:

dentons-logo2

silver-level

samsung-logo

siemens-new-original

philips-icus-logo

Contact ICUS

  • Address: 1900 K Street, N.W.
    Washington, DC 20006-1102, USA
  • Telephone: 202-408-6199

About ICUS

ICUS is the world’s only professional society exclusively devoted to contrast-enhanced ultrasound (CEUS) medical imaging technology.

Learn more...

You are here: Home ICUS Weekly News Monitors ICUS Weekly News Monitor 4-20-2018