- Category: ICUS Weekly News Monitors
- MedicalXpress, Nov 30, 2016, Faster, non-invasive method to determine the severity of a heart failure (Eindhoven University of Technology)
- DOTmed.com, Healthcare Business, Nov 29, 2016, Physicians at RSNA make case for contrast-enhanced ultrasound by John W. Mitchell
- Breast Cancer News, Nov 9, 2016, Mammogram Alternative Would Be Radiation-Free, Less Uncomfortable By Ines Martins, PhD
Nov 30, 2016
Faster, non-invasive method to determine the severity of a heart failure
Provided by: Eindhoven University of Technology
Methods currently employed to determine the severity of a heart failure are very limited. Researchers at TU/e and the Catharina Hospital in Eindhoven have therefore developed a method that is very quick, non-invasive, cost-effective and can be performed at the hospital bedside. Moreover, this method appears to have a predictive value for whether or not a double pacemaker will be successful. Researchers Ingeborg Herold and Salvatore Saporito received their doctorates earlier this month for their study.
Heart failure – when the heart is no longer able to pump enough blood through the body – is a very common problem. To get the right treatment, it is important to measure how well the heart is still able to do its job. There are currently various methods for doing this, but all have their limitations. Sensors often need to be placed in the large arteries, via the shoulder or neck, and that is quite an invasive procedure. MRI is a possibility, but not for patients that are seriously ill. Patients that are short of breath nearly always undergo blood analysis, a method that examines the concentration of a particular protein in the blood and provides a very good, patient-friendly indicator, but it takes several hours before the outcome is known.
The Eindhoven researchers have developed a patient-friendly method that uses an echo scanner, which is known mainly for echoes performed during pregnancy, to determine the severity of heart failure. To do this, they measure the time it takes for the blood to travel from the heart's right ventricle through the lungs to the left ventricle, which is responsible for pumping oxygenated blood through the body. In order to measure this pulmonary transit time (PTT), they inject harmless microbubbles that can be seen clearly by the echo scanner. They then look at the heart and see how long it takes for the bubbles to get from the right to the left ventricle.
It may seem simple enough but there was a significant scientific challenge in calculating an unequivocal PTT for the observed microbubbles that get dispersed in the blood flow. But once that had been solved, they compared the transit time with a number of existing indicators, developing a similar method on the basis of MRI. Comparisons revealed that the PTT measured with the echo scanner provides an excellent indicator for the severity of a heart failure. A healthy heart pumps the blood quickly through the lungs. The longer the PTT, the less well the heart performs. They examined subjects whose heart muscle no longer contracted well, which is the most common type of heart failure. Before the method can be used, there is still work to be done. For example, if it is to be both practical and fast, the analysis will have to be automated.
Another aspect being studied is the extent to which the PTT is able to predict the success of a double pacemaker, whose primary objective is to restore the synchronicity of the two ventricles of the heart. Herold indeed found that there was a fairly firm relationship between the transit time and the success rate. The breaking point is 12.5 seconds; above that, the chance of the pacemaker enabling the heart to perform better reduces. But any application of this indicator requires more research, says Herold. Because the method does not appear to be completely accurate in the prediction, she expects it to be useful in combination with other indicators.
The method is founded on the work of TU/e researcher Massimo Mischi, who has spent a decade working on the development of 'contrast enhanced ultrasound (CEUS)' for analyzing the blood flow using microbubbles as a contrast medium. He has already done this successfully to detect prostate cancer.
Ingeborg Herold gained her doctorate on Thursday 17 November for her thesis 'Assessment of cardiopulmonary function by contrast enhanced echocardiography' while Salvatore Saporito received his PhD the same day for his thesis 'Cardiovascular MRI quantifications in heart failure'.
Nov 29, 2016
Physicians at RSNA make case for contrast-enhanced ultrasound
by John W. Mitchell
Physicians from the U.K., Canada and Italy presented case studies from their use of contrast enhanced ultrasound (CEUS) at the RSNA meeting in Chicago.
The procedure, which was OK’d by the FDA this year for liver screening, but is currently not approved in the U.S. for cardiac disease, shows particular value in imaging children who may otherwise have to
Dr. Paul Sidhu, a radiologist and professor at King’s College in London, made the case that adopting CEUS is as much a philosophical choice as clinical.
“One of the main reasons to adopt CEUS is to reduce radiation burns that we seem to inflict upon our patients,” he told a large Monday morning audience at a Samsung-sponsored event.
He noted the use of CT scans in the U.S. has risen from about three million in 1980 to roughly 80 million in 2015. This is troubling, he noted, as it’s estimated that between 1.5 and 2 percent of cancers, including leukemia, in the U.S. may be attributed to organ dose radiation from CT exams. CEUS offers a radiation-free alternative to CT scanning in diagnosing liver ailments and injuries.
Based on his experience, he said that CEUS has several advantages over CT, as well as MR. CEUS can be performed immediately, with no lab testing. It is also portable and can and it can be conducted at multiple locations, such as the bedside, operating room or in the CT suite. It also operates and provides results in real time, allowing rapid changes to be recorded. He also reported lower adverse rates than for CT or MR.
The addition of a contrast line into a venous line does require two operators and the use of the contrast adds almost five minutes to the procedure, but according to Sidhu, the image study results are worth the trade-off. He cited a journal article that concluded: “CEUS and MR are of equal value for the differentiation and specification of newly discovered tumors in clinical practice.”
Another speaker at the event, Dr. Stephanie Wilson, professor of radiology at the University of Calgary, Canada, spoke about her one-week conducting these procedures using the Samsung RS80A with Prestige. She reported very competent diagnostic capabilities for cirrhosis patients and said that using color Doppler was especially helpful in liver diagnosis of obese patients.
“While none of these findings have yet been confirmed (due to the short amount of time she had the machine before the conference) ... I think the findings will be confirmed,” Wilson told the audience, adding that she would present these results and other findings on CEUS diagnostics at next year's RSNA meeting.
The final presenter, Dr. Vito Cantisani, an Italian cardiologist, presented findings on his success using CEUS in diagnosing different types of heart plaques (an application that is not currently approved in the U.S.). He noted that cardiovascular disease contributes up to 10 percent of deaths worldwide, and diagnosing plaques is critical in reducing heart attack and strokes.
Breast Cancer News
Nov 9, 2016
Mammogram Alternative Would Be Radiation-Free, Less Uncomfortable
By Ines Martins, PhD
Researchers are working to develop a new breast-friendly, radiation-free method that may replace the unpleasant mammogram currently used to detect breast cancer.
The new method, described in the study “Towards Dynamic Contrast Specific Ultrasound Tomography,” and published in Scientific Reports, uses ultrasounds to provide 3-D images of the breast, and is meant to reduce not only a woman’s discomfort during the procedure, but also the number of false-positive results seen frequently with current mammogram methods.
Currently, women are screened for breast cancer through a mammogram, where the breast is squeezed tight between two plates to generate 2D X-ray images. The method is not only physically unpleasant and one of the reasons women choose to skip screening, it also comes with the risk that the radiation used in the mammograms can contribute to the development of cancer.
In addition, mammograms generate large numbers of false-positive results. In more than two-thirds of cases where doctors find an abnormal tissue that is recommended for biopsy, it turns out that the abnormal regions are not cancer. In the meantime, women are subjected to high levels of unnecessary worrisome stress.
Researchers have been trying to develop alternatives to this method that provide more accurate results and that reduce women’s discomfort. Recently, a team at Eindhoven University of Technology has been working on a possible alternative for mammograms.
According to a press release, the new technology requires patients to lie on a table with their breast hanging freely in a bowl. Using ultrasounds, a 3-D image of the breast is generated and scanned for tumors. The researchers believe this method will generate far fewer false negative results.
The technology builds up on a patient-friendly prostate cancer detection method also developed at the Eindhoven University of Technology. The approach takes advantage of the distinct vessel architecture found in tumors and healthy tissues. Tiny micro-bubbles that can be precisely monitored with an
echoscanner are injected in the prostate blood vessels, allowing doctors to precisely identify the presence and location of the tumor.
Although this method is now being tested for prostate cancer in hospitals worldwide, breast motion and size have largely limited its application in breast cancer screening.
But researchers may have developed a new variant of the echography method that is suitable to be used in breast cancer. Libertario Demi, Ruud van Sloun and Massimo Mischi developed the Dynamic Contrast Specific Ultrasound Tomography, which uses the same micro-bubbles, but under a different principle. They use the fact that bubbles vibrate in the blood at the same frequency as the sound produced by the echoscanner, and at twice that frequency — the second harmonic.
When the scanner captures that vibration, it knows where the bubbles are located. Similar to the micro-bubbles, the body tissue also generated harmonics, which limited the researchers’ observations. But the researchers found that, contrary to the body tissues, the gas bubbles delayed the second harmonic. And the more bubbles the sound-waves encountered, the bigger the delay.
This, however, can be detected only if the sound is captured on the other side, which makes the technology ideal for the breast tissue.
The researchers are now starting a collaborative effort to conduct preclinical studies with the new tool, and hope it will be included in clinical practice within 10 years, possibly in combination with other methods that will generate high-quality images that allow for highly accurate diagnoses.