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MRI SCANNING/RADIOLOGY 

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MRI: the X factor that’s changing the world of health
Advances 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 interpreted data.

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 out.

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 sedated.

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 trimester.

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, Fonar’s 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
state.

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 MRI.

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 company’s 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 MRI systems.

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.


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