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MR is abbreviated as Magnetic Resonance which is used in radiology as a non invasive medical imaging technique to visualize the functional aspect of the anatomical structures in detail. This imaging technique utilizes nuclear magnetic resonance property to image nucleus of atoms in the human body. As compared to X-rays, MR imaging technique can generate better and detailed images. MR scanners make use of highly powerful magnet which generates a magnetic field that will align the atomic nuclei in the body by magnetization. The alignment caused due to this magnetization is altered by systematically applying radiofrequency magnetic fields. This leads to the formation of magnetic field by the nuclei that can be detected by the scanner¬¬ which is recorded in order to construct the image of the area in the body that is scanned. The atomic nuclei at different locations move at a different speed because of the magnetic field gradients allowing spatial information to be recovered. Two-dimensional or Three-dimensional images can be reconstructed in any arbitrary orientation by applying gradients in different locations. There are 2 properties that are necessary in a magnetic field and that is uniformity in the field density and strength. Tesla is the unit of measurement for the magnetic field strength. There cannot be a variation in the magnetic field more than 1/10,000 of 1% and the strength of the field would range from 0.2 – 3.0 Tesla in the scanners that are currently in clinical use. For Claustrophobic patients “open” MRI is often used which has permanent magnets that help to achieve lower field strengths. When super conducting magnets are used higher field strengths can be achieved. There are many clinical research studies that makes use of increased field strength i.e. 7.0 Tesla, although rare, as the suitable coils for 7 Tesla have a limited availability in hospitals. Therefore, even though 1.5 Tesla magnetic resonance scans are good, 3 Tesla can characterize some minute abnormalities much better than 1.5 Tesla. Use of high field strength in MRI (>1.5 Tesla) can precisely describe the structures that has not been seen before; for example, blood vessels which has a size of only 200 to 300 microns, thus generating imaging of ultra structural level. Using a 3 Tesla MRI is much more than a high resolution microscope.3 Tesla MRI can perform everything that a 1.5 Tesla MRI can, but better and quicker. Thus using 3 Tesla MRI in clinical trials has a better scope. A higher signal to noise ratio can be obtained with the use of 3 Tesla MRI when compared to 1.5 Tesla. Because of this 3 Tesla can correctly locate area of activation thus enabling a better imaging on cell function. A 3 Tesla body coil can produce about the same signal to noise ratio as compared to 1.5 Tesla array coil. If a surface coil is added to this, it increases the signal to noise ratio and hence allows better resolution scans and a faster acquisition of scans. These images with higher resolution reveal detailed anatomical structures and physiological parameters. Clinical techniques that are potentially insensitive can be made robust with the use of three Tesla. New machines from most of the manufacturers for 3 Tesla MRI have software platforms that are standardized across the whole of magnetic resonance product line. Therefore, 3 Tesla magnetic resonance shares similar parameters and user interface like MRI scanners that use 1.5 Tesla. The shift from 1.5 Tesla to 3 Tesla has been much easier in the perspective of engineering and optimization. Limitation of 3 Tesla compared to 1.5 Tesla: Since 3 Tesla MRI uses high radio – frequency exposure it leads to a decrease in the number of slices that can be scanned and the speed at which scans are taken due to the physiologic human limitations. Radiologists find it difficult to obtain reliable and consistent protocol as the same plug-ins used for 1.5 Tesla cannot be used in 3 Tesla MRI. Because of this the protocols needs to be modified as 3 Tesla uses high radio frequency, that is, four times higher than 1.5 Tesla. As there is a difference in the amount of contrast used in 1.5 Tesla and 3 Tesla MRI, the radiologists have to redefine the interpretation of the data obtained through MRI scanning. Even though there are certain limitations to 3 Tesla MRI imaging, at least in the short term, it has targeted in providing improved detailing of the images of the human organs and tissues and also identifies minute lesions that are buried under the highly complex anatomy. Thus 3 Tesla MRI seems promising to be an advanced technology in medical imaging that balance clinical application and research study. Clinnovo Research Labs is a clinical innovation company. It is pioneer CRO industry in India. Clinnovo offers professional clinical research course , clinical data management course , SAS and Imaging Training. Clinnovo has been serving different bio-pharma industries across the world with excellence and high quality. For more information contact at +91 9912868928, 040 64635501
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