Features | Partner Sites | Information | LinkXpress
Sign In
Schiller
VIEWORKS
TeraRecon

Simulations Demonstrate Neutron-Stimulated Emission CT and Gamma-Stimulated Emission CT to Be Safe

By Medimaging International staff writers
Posted on 16 Jun 2014
Image: Simulated three-dimensional (3D) dose measurements of the breast showing the dose imparted to the whole body. The dose is shown on a red and yellow color map, where yellow shows maximum dose (Photo courtesy of Duke Medicine).
Image: Simulated three-dimensional (3D) dose measurements of the breast showing the dose imparted to the whole body. The dose is shown on a red and yellow color map, where yellow shows maximum dose (Photo courtesy of Duke Medicine).
Image: Simulated 3D dose measurements of the abdomen/liver showing the dose imparted to the whole body. The dose is shown on a red and yellow color map, where yellow shows maximum dose (Photo courtesy of Duke Medicine).
Image: Simulated 3D dose measurements of the abdomen/liver showing the dose imparted to the whole body. The dose is shown on a red and yellow color map, where yellow shows maximum dose (Photo courtesy of Duke Medicine).
Gamma and neutron imaging offer possible enhancements over existing imaging techniques such as X-ray or computed tomography (CT), but their safety has not yet been fully determined. Using computer simulations, imaging the breast and liver with gamma or neutron radiation was found to be safe, delivering levels of radiation comparable with conventional medical imaging, according to researchers.

The findings, published in the June 2014 issue of the journal Medical Physics, will help researchers to move evaluation of gamma and neutron imaging into animals and later humans. Standard medical imaging tools, including X-ray, ultrasound, CT, and magnetic resonance imaging (MRI), identify disease by finding the anatomy, or shape and size, of the abnormality. When applying these applications to screen for cancer, a tumor must be large enough to be detected, and if found, a surgical biopsy is typically needed to determine if it is benign or malignant.

Duke University (Durham, NC, USA) researchers are working to develop imaging technologies to detect disease in its earliest stages, much before the tumors grow large enough to be detected using traditional approaches. Two imaging techniques they are researching are neutron-stimulated emission CT and gamma-stimulated emission CT.

Research has shown that many tumors have an out-of-balance concentration of trace-level elements naturally found in the body, such as rubidium and aluminum. These elements stray from their normal concentration levels at the earliest stages of tumor growth, potentially providing an early indication of disease.

The neutron and gamma imaging modalities measure the concentrations of elements in the body, determining molecular characteristics without the need for a biopsy or injection of contrast media. The goal is for these tests to be able to distinguish between benign and malignant lesions, as well as healthy tissue. “Gamma and neutron imaging may eventually be able to help us to detect cancer earlier without having to perform an invasive biopsy,” said Anuj Kapadia, PhD, assistant professor of radiology at Duke University School of Medicine and the study’s senior author.

Gamma and neutron imaging may also have applications for patients undergoing cancer treatment. Patients currently wait weeks or months to see if their cancer is responding to a particular treatment and shrinking in size, but gamma and neutron imaging may be able to tell if a treatment is working earlier by detecting molecular changes directly within the tumor.

While improved diagnostic tests would provide clinicians with useful tools, one ongoing question is the safety of gamma, and in particular, neutron radiation. Upon entering the body, neutrons scatter considerably, with the possibility of reaching several vital organs. Therefore, researchers have been apprehensive about how much radiation is absorbed in the targeted organ versus surrounding tissue. For instance, in a breast scan, the researchers need to know how much radiation is delivered unnecessarily to the heart or lungs.

Using detailed computer simulations, Dr. Kapadia and his colleagues estimated the radiation dose delivered to the liver and breast using neutron and gamma imaging. They found that the majority of radiation was delivered to organs directly within the radiation beam, and a much lower dose was absorbed by tissue outside of the radiation beam.

In simulated breast scans, the radiation was almost entirely limited to the area of the breast being scanned. The dose to the breast accounted for 96% of the radiation in neutron scans and 99 percent in gamma scans. The heart and lungs received less than 1% of the radiation dose.

When imaging the liver in simulation, the neutron scan imparted the highest radiation dose to the liver, while in the gamma scan, the stomach wall absorbed the greatest amount of radiation because of its location in the direct path of the beam. Further research is needed to decrease and better target gamma radiation doses in liver scans, according to the investigators. “The results show that despite the use of a highly scattering particle such as a neutron, the dose from neutron imaging is on par with other clinical imaging techniques such as X-ray CT,” Dr. Kapadia concluded. “Neutron and gamma radiation may become viable imaging alternatives if further testing proves them to be safe and effective.”

The researchers will use these data to move their studies into animals, and later, human trials.

Related Links:

Duke University



Channels

Radiography

view channel

Coronary CT Used to Measure a Recreational Athlete's Risk of a Cardiovascular Event

Researchers presented the results of the Measuring Athlete's Risk of Cardiovascular events (MARC) study at the 2015 European Congress of Radiology (ECR) in Vienna (Austria).  Researchers at the University Medical Center Utrecht (UMC; Utrecht, Netherlands) investigated the added value of low-dose ECG-triggered Coronary... Read more

MRI

view channel

Bayer Shows its Latest Development in MR Injectors

The latest contrast delivery and management innovation from Bayer HealthCare takes the form of the Medrad MRXperion magnetic resonance Injection System, launched at the European Congress of Radiology 2015 in Vienna (Austria). Bayer (Leverkusen, Germany) has begun to introduce the product in select countries with commercial... Read more

Ultrasound

view channel

Breakthrough Ultrasound Treatment for Alzheimer's Developed

A new, revolutionary technique that can be used to treat Alzheimer's disease and restore memory has been discovered by researchers at the University of Queensland (Queensland, Australia). The treatment uses noninvasive ultrasound to break apart neurotoxic amyloid plaques that cause cognitive decline and memory loss,... Read more

General/Advanced Imaging

view channel
Image: Measuring the Magnetic Activity in the Brain of a Child, Using a MEG machine. (Photo courtesy of Children\'s Hospital of Philadelphia).

Study Suggests Language Delay Linked to Chromosome Deletion in Children with Neurological Disorders

A study found that children with neuro-developmental problems born with DNA duplications or deletions on part of chromosome 16, show measurable delays in their ability to process sound and language.... Read more

Imaging IT

view channel

New Release of Image Management and Advanced Visualization Solution Unveiled at ECR 2015

A new version of an enterprise medical image management and advanced visualization solution has been launched at the 2015 European Congress of Radiology (ECR) in Vienna (Austria). The visualization solution provider also released new processing capabilities for cardiac Magnetic Resonance (MR), optimized low-dose workflow... Read more

Industry News

view channel

Analysis of Worldwide CT Scanner Sector Released

A report by Kalorama Information (New York, NY, USA) analyzing the global Computed Tomography (CT) market has been published. The report surveyed the CT market outlook until 2018, and the drivers behind the changes. The report investigated CT market sizing, market forecast to 2018, analysis of trends, how the market... Read more
 
Copyright © 2000-2015 Globetech Media. All rights reserved.