News | June 12, 2009

Study Shows New Contrast Agent May Identify Vulnerable Plaque

3D rabbit heart spiral CT images enhanced using the N1177 contrast agent.

June 12, 2009 - NanoScan Imaging LLC today announced the publication of new data demonstrating the use of its investigational, radio-opaque contrast agent (N1177) to visualize vulnerable plaques that can cause heart attack or stroke using advanced, noninvasive and high-resolution computed tomography (CT) techniques.

Results of the study were published in the current issue of the Journal of Nuclear Medicine (June 2009, pages 959-965).

N1177, an emulsified suspension that is composed of crystalline iodinated particles dispersed with surfactant, is being developed to visualize blood vessels and organs of the body, with particular interest in the arteries, veins and the heart chambers using a technique known as CT angiography (CTA). N1177 also accumulates in macrophage cells allowing for their detection with CT.

Macrophages are the predominant cells involved in creating the progressive plaque lesions of atherosclerosis, a progressive disease and the main cause of cardiovascular disease - the number one killer worldwide. Atherosclerosis is caused by the build-up of plaques (fatty or fibrous deposits) in the artery walls. This can result in the narrowing of the arteries, which can reduce the supply of blood to vital organs such as the heart and brain. Plaques can also rupture, leading to a sudden, complete blockage of blood flow. Plaques that are at high-risk or “vulnerable” to rupture are characterized by strong macrophage infiltration, which result in acute plaque destabilization and thrombus formation.

In the study, researchers from the Mount Sinai School of Medicine investigated whether or not N1177 correlated with macrophage activity evaluated with 18fluorine-fluorodeoxyglucose (FDG) on PET/CT and also macrophage density on histology. After only two hours, the enhancement of the macrophage rich plaque after the injection of N1177 was significantly higher and specific inside of the vessel wall in rabbits fed a high cholesterol diet compared to control rabbits fed a normal chow diet (p

Several noninvasive imaging techniques have been investigated for macrophage detection in atherosclerotic plaques. For example, ultrasmall superparamagnetic particles of iron oxide (USPIO) are taken up by macrophages that can be detected as signal voids using magnetic resonance imaging (MRI) or combined with a radiotracer to quantify the accumulation of these particles using PET. However, high spatial and temporal imaging resolutions required for imaging the arterial wall of coronary arteries are currently achievable neither with PET nor with MRI. In addition, the optimal imaging time after the injection of iron oxide nanoparticles may be up to 72 hours, limiting the practical use of this technique as a screening tool.

By comparison, CT offers to detect macrophage-rich lesions as early as two hours after the intravenous injection of N1177 with a spatial resolution allowing for the evaluation of coronary atherosclerotic plaques. Quantification of N1177 accumulation in atherosclerotic plaques is facilitated by the linear relationship existing between iodine concentration in tissue and signal increase measured with CT. In addition, detection of macrophages with N1177 could be used in connection with other CT markers identified in ruptured plaques such as areas of low densities, positive remodeling and absence of calcifications to enhance the potential of CT to identify high-risk plaques.

N1177 is cleared through the liver unlike traditional contrast agents that are cleared through the kidneys, which can result in renal toxicity.

For more information: www.nanoscanimaging.com

Related Content

New Study Redefines Therapeutic Dose Guidelines for Non-Small Cell Lung Cancer
News | Lung Cancer | April 23, 2019
Non-small cell lung cancer is a common cancer for both men and women. Many people who are diagnosed with this type of...
Comparison of state Medicaid fees for radiation oncology services for breast cancer and nonradiation oncology services per the Kaiser Family Foundation Index

Fig. 1: Comparison of state Medicaid fees for radiation oncology services for breast cancer and nonradiation oncology services per the Kaiser Family Foundation Index. (Agarwal et al, Red Journal, 2019) Credit: Elsevier

News | Radiation Therapy | April 22, 2019
April 22, 2019 — A new study finds wide state
Stereotactic Radiosurgery Effective for Pediatric Arteriovenous Malformation Patients
News | Radiation Therapy | April 19, 2019
Ching-Jen Chen, M.D., of the neurosurgery department at the University of Virginia (UVA) Health System, was the winner...
Video Plus Brochure Helps Patients Make Lung Cancer Scan Decision

Image courtesy of the American Thoracic Society

News | Lung Cancer | April 19, 2019
A short video describing the potential benefits and risks of low-dose computed tomography (CT) screening for lung...
Surgically Guided Brachytherapy Improves Outcomes for Intracranial Neoplasms
News | Brachytherapy Systems | April 18, 2019
Peter Nakaji, M.D., FAANS, general practice neurosurgeon at Barrow Neurological Institute, presented new research on...
Ebit and DiA Imaging Analysis Partner on AI-based Cardiac Ultrasound Analysis
News | Cardiovascular Ultrasound | April 16, 2019
DiA Imaging Analysis has partnered with the Italian healthcare IT company Ebit (Esaote Group), to offer DiA’s LVivo...
Check-Cap Initiates U.S. Pilot Study of C-Scan for Colorectal Cancer Screening
News | Colonoscopy Systems | April 15, 2019
Check-Cap Ltd. has initiated its U.S. pilot study of the C-Scan system for prevention of colorectal cancer through...
Example of full-dose, 10 percent low-dose and algorithm-enhanced low-dose. Image courtesy of Enhao Gong, Ph.D.

Example of full-dose, 10 percent low-dose and algorithm-enhanced low-dose. Image courtesy of Enhao Gong, Ph.D.

Feature | Contrast Media Injectors | April 11, 2019 | By Jeff Zagoudis
One of the most controversial issues in radiology in recent years has been the use of...
DiA Imaging Analysis Introduces LVivo SAX Ultrasound Analysis Tool
Technology | Cardiovascular Ultrasound | April 09, 2019
DiA Imaging Analysis announced the launch of LVivo SAX, a cardiac analysis tool that helps clinicians quickly and...
Deep Lens Closes Series A Financing for Digital AI Pathology Platform
News | Digital Pathology | April 09, 2019
Digital pathology company Deep Lens Inc. announced the closing of a $14 million Series A financing that will further...