MRI: the X factor thats changing the world of
in research have focused so much on minimising the need for invasive surgical procedures
that a significant shift has occurred in which medical practitioners, for many procedures,
no longer have to operate on, or even directly touch patients. MRI is one such technology
that continues to benefit from research, and the manufacture of new equipment, across the
globe. BERNADETTE DELVES reports.
|The integration of
clinical expertise and innovative research has promoted continuous ad-vances in MRI with
dedicated whole body imaging allowing for the rapid development of new approaches.
Today, collaborative groups across the globe are engaged in enhancing the diagnostic value
of MR imaging through the pursuit of fast imaging approaches, 3D volumetric imaging
techniques and physiological imaging. Emphasis continues to be on image and processing
time, costs and patient discomfort, as well as maximising resolution and displaying easily
Recent advancements allow for an increase in speed and efficiency in the detection and
treatment of many widespread medical problems and much research continues to be carried
One study shows that MRI is a beneficial addition to ultrasound when evaluating foetal CNS
abnormalities. Traditionally these studies have been limited by foetal motion, but due to
the fast imaging techniques which are now available, images can be obtained in less than
half a second. The advantage of this is that neither the mother nor the foetus needs to be
It can also be used to obtain multiplanar views and direct visualisation of the brain
parenchyma, which allows for detailed visualisation of the CNS anatomy something
which is difficult to obtain with sonography. During these studies, using the ultrasound
and MRI method, researchers have, due to theoretic concerns, avoided scanning in the first
Clinical trials are also currently being undertaken as to the possibility of using MRI to
scan coronary arteries for blockages.
The far-reaching benefits of using this method in the future for treating heart disease -
still a major cause of disability and fatalities across the globe - is that it does not
require x-ray exposure or injection of contrast dye.
In addition, an application has also been developed to advance the visualisation of blood
supply to the heart. This method can also supply information on which area is impaired and
also how large the deficit is.
For the treatment of antheroma, methods have also been created to examine blood vessels
directly with the goal of identifying chemical changes inside artery walls before any
damage occurs. This is rather than the traditional method of inferring what might be
happening from the monitoring of blood or cholesterol levels.
This will allow the response of antheroma patients to be monitored with regard to diet and
any other interventions as a guide to effective treatment. So far, work has mainly been
done on excised blood vessel samples. Current investigations are aimed at applying the
developed methodologies clinically.
For earlier detection of the region in the brain where a stroke has occurred, a method has
also been developed to scan for the movement of water in the brain. This technique offers
doctors both the option of more accurate early analysis and the opportunity to monitor the
effectiveness of various therapeutic interventions. Such early intervention is critical to
saving brain tissue injured during an attack.
Another useful application of the technology has been demonstrated in the mapping of
cerebral brain activity while it performs specific tasks. Visualisation of the function
associated with a particular part of the brain activity has become critical in surgical
planning, investiga-tion of psychiatric diseases and understanding how the brain works.
MRI can be used to provide high-resolution images of the functional brain
using totally non-invasive methods. It is sensitive to blood flow in the brain so as the
flow increases to active regions, it can be used to image which parts of the brain are
activated with certain tasks.
This includes moving muscles, perceiving language, or making mental images, so the
methodology is being used to investigate how brain networks are being organised for
thought and action. Many laboratories around the world have, or are in the process of
obtaining, access to facilities for the recording of functional MRI.
Finally, virtual colonoscopy has the potential to become an alternative to minimally
invasive colorectal cancer screening tests, having advantages such as the better detection
of polyps of all sizes and the lack of ionising radiation. However, because of concerns
regarding artefacts due to air, current practice involves the administration of a
one-two-litre enema containing a dye in order to distend the colon.
Although there are presently no studies comparing MR colonography using an enema and MR
colonography using air insufflation, studies comparing barium enema and CT colonography
suggest that air distention is better tolerated than a fluid enema. Researchers are
currently exploring the use of air and carbon dioxide (associated with less bowel spasm)
as an alternative to a fluid enema.
As studies in the uses of the technology continue, upgraded and new equipment,
manufactured by leading suppliers, makes the task for healthcare professionals easier and
more financially viable all the time.
Siemens offers an upgrade of its Magnetom Open Viva#P with a permanent magnet to Magnetom
Concerto. This has the advantages of shorter examination times, improved workflow and
increased patient throughput, as well as a wider range of diagnostic applications and low
life cycle costs.
Alongside this, a completely new Concerto Integrated Panoramic Array&trade is
available, including a comprehensive set of coils. The new Head Neck Array Coil and Body
Spine Array Coils increase workflow and lower parts of the coils can be kept on the table
for most of the exams, avoiding excessive patient positioning.
Alternatively, Fonars Indomitable uses what the company calls a revolutionary
stand-up design, allowing all parts of the body, particularly the spine and joints, to be
imaged in the weight bearing
This system is equipped with a unique MRI-compatible motorised patient handling system
that will move the standing patient into the magnet and place the anatomy of interest into
the centre of the magnet gap. It can also rotate the standing patient into a horizontal
position so that the patient can be scanned lying down, as is the case of a traditional
There are more upcoming products being created by Resonance Technology, Inc. A headset,
which features active noise cancellation, is now being developed.
The company states that this microprocessor-controlled system will filter and cancel
gradient noise for the clearest audio signal.
3D stimulation hardware and software, to work in conjunction with the companys
VisuaStimXGA, is also in the design stages.
The Software will allow users to import 3D models and static images, synchronise with EPI
pulse track and record patient response for later analysis.
Hitachi claims to have set the global standard in permanent magnetic-based, multi-purpose
It calls the new mrp-5000ad, a combination of eddy-current free permanent magnet and high
performance computer, leading edge QD coils and sophisticated new software.