Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING LLC
Schiller
Ampronix

Calibration Tools Used to Enhance Ultralow Field MRI Technology

By Medimaging International staff writers
Posted on 16 Dec 2013
Image: NIST physicist Michael Boss positions a prototype NIST phantom in an ultralow-field magnetic resonance imaging scanner at the University of California at Berkeley. NIST phantoms are intended to help assess and validate this experimental imaging method, which offers advantages in diagnosing and monitoring of certain medical conditions (Photo courtesy of NIST).
Image: NIST physicist Michael Boss positions a prototype NIST phantom in an ultralow-field magnetic resonance imaging scanner at the University of California at Berkeley. NIST phantoms are intended to help assess and validate this experimental imaging method, which offers advantages in diagnosing and monitoring of certain medical conditions (Photo courtesy of NIST).
A US technology office has developed prototype calibration tools for an experimental medical imaging technique that offers new benefits in diagnosing and tracking of specific cancers and other medical disorders.

The US National Institute of Standards and Technology (NIST; Gaithersburg, MD, USA) designed, built, and evaluated two prototype phantoms for calibrating ultralow-field (ULF) magnetic resonance imaging (MRI) systems.

The NIST prototypes are the first standard calibration tools for ULF-MRI, offering a quantitative means to assess performance, validate the technique, and directly compare different experimental and clinical MRI scanners. “Tissues that may look the same in clinical MRI can look very different in ULF-MRI, which provides new contrast mechanisms,” NIST physicist Dr. Michael Boss stated. “Our hope is that we can move this technique along to attract more interest from [industry] vendors.”

MRI noninvasively images soft tissues based on measurements of how hydrogen nuclei respond to magnetic fields. ULF-MRI enhances tissue contrast in specific types of MRI scans. Prostate tumors, for example, can be difficult to see with conventional MRI but show up clearly under ULF-MRI. ULF-MRI has also been used in research approaches to image the brain, and assessed in at least one nonmedical application, inspection of liquids at airports.

ULF-MRI also offers practical advantages: the systems are more streamlined, lighter in weight, and less costly than conventional MRI scanners. That is because ULF-MRI operates at much lower magnetic field strengths, measured in micro-Teslas, thousands of times lower than conventional MRI, which operates at up to 3 Teslas and requires large magnets. The low magnetic field strength means ULF-MRI requires the most sensitive magnetometers available: superconducting quantum interference devices (SQUIDs). This is convenient in that it makes ULF-MRI suitable for combining with other SQUID-based imaging techniques such as magnetoencephalography.

NIST scientists earlier designed phantoms for standard MRI systems and also have extensive experience both making and using SQUIDs. NIST’s new ULF-MRI phantoms are short plastic cylinders, shaped like hockey pucks but a bit smaller, containing six or 10 plastic jars filled with various salt solutions that become magnetized in a magnetic field. Each phantom measures a different aspect of scanner performance such as spatial resolution. NIST researchers tested the new phantoms on both a conventional MRI system at the University of Colorado Health Sciences Center (Denver, CO, USA) and a research ULF-MRI scanner at the University of California (UC) at Berkeley, where the technique was first demonstrated about than 10 years ago.

Tests findings revealed that the prototype phantoms are well matched to ULF-MRI applications and they allow direct comparison of ULF and clinical MRI system performance. NIST researchers now plan to integrate design improvements based on lessons gleaned from the prototypes, with the aim of improving phantom stability and providing traceability to standard measurement units. NIST and the University of California (UC) Berkeley (USA) researchers also plan to work together to develop ULF-MRI technology for the detection of prostate and breast cancers.

NIST’s phantoms for conventional MRI systems are currently being tested by hospitals and MRI manufacturers, and Sigma-K Corp. (Durham, NC, USA) is devising ways for making copies for more widespread distribution under a NIST Small Business Innovation Research Award (SBIR).

The study’s findings were published online November 26, 2013, in the journal Magnetic Resonance in Medicine.

Related Links:

National Institute of Standards and Technology
University of California, Berkeley
Sigma-K



Channels

Radiography

view channel

Reprogramming Stem Cells May Suppress Cancer after Radiotherapy

The body has developed strategies of purging defective stem cells. A new study has revealed that one of these ways is a “program” that makes stem cells damaged by radiation differentiate into other cells that can no longer survive forever. Radiation makes a stem cell lose its “stemness,” which makes sense because damaged... Read more

Ultrasound

view channel

Guidelines Released for Quantitative Monitoring of Critically Ill and Surgery Patients Using Echocardiography

The American Society of Echocardiography (ASE; Morrisville, NC, USA) has published clinical guidelines describing how and when echocardiography can be used for medical and surgical therapy in adult patients. The guidelines were published in the January 2015 issue of the American Society of Echocardiography.... Read more

Nuclear medicine

view channel
Image: Created by averaging PET scan data from chronic pain patients (left) and healthy controls (right), the images reveal higher levels of inflammation-associated translocator protein (orange/red) in the thalamus and other brain regions of chronic pain patients (Photo courtesy of Marco Loggia, Martinos Center for Biomedical Imaging, Massachusetts General Hospital).

PET/MR Imaging Shows First Evidence of Neuroinflammation in Chronic Pain Patients’ Brains

For the first time, researchers have used neuroimaging strategies to find evidence of neuroinflammation in major regions of the brains of patients with chronic pain. By showing that levels of an i... Read more

General/Advanced Imaging

view channel
Image: Dr. Miles was part of the team that helped identify facial measurements in children with autism that may lead to a screening tool for young children and provide clues to its genetic causes (Photo courtesy of Rebecca F. Miller).

Advanced 3D Facial Imaging Designed to Help in Early Identification of Autism

Autism is a range of closely related disorders observed in patients who exhibit a shared assortment of symptoms, including delays in learning to communicate and interrelate socially. Early detection of... Read more

Imaging IT

view channel
Image: NEC Display Solutions MD210C3 Diagnostic Review Monitor (Photo courtesy of NEC Display Solutions).

New Cost-Effective Diagnostic Review Monitor Receives FDA 510(K) Clearance

The monitor is intended as an affordable tool for viewing diagnostic images on the Picture Archiving and Communication System (PACS). The 3-megapixel monitor has a 21.3-inch diagonal color Liquid Crystal... Read more

Industry News

view channel

Expected Revenues of Hologic Up in First Quarter of 2015

Hologic (Bedford, MA, USA), a global healthcare and diagnostics company, has announced that it expects total revenues for first fiscal quarter of 2015 to reach approximately USD 653 million—7% more than the year before. The company provided the business updates in preparation for its participation in the 33rd Annual J.... Read more
 
Copyright © 2000-2015 Globetech Media. All rights reserved.