Introduction
The Tesla, whose symbol is T, is an international standard of unit’s derived measure for magnetic flux intensity, commonly denoted as B. In the technical field of magnetic resonance imaging (MRI), Tesla (T) is the measurement unit of computing the power of a magnetic field. Before the usage of the 3 Tesla power systems, the strongest field used in medical imaging was 1.5 Tesla.
The new 3 Tesla system generates twice the strength of the previously used 1.5 Tesla imaging system, and can offer 10 to 15 times the power of open MRI scanning systems. The new 3 Tesla system of imaging produces brilliant atomic elements and offers higher image clarity, which is exactingly productive for pathological situations, especially on internal organs, the musculoskeletal system and spine injuries.
The model’s benefits are not only confined to magnetic resonance imaging, but also the high level spatial resolution of the system, which allows for high definition vascular imaging. The system is further, highly efficient, registering shorter scanning durations, and offering increased patient comfort without compromising the quality of the imaging results.
The success of the higher field imaging technology has attained such high levels of usage preference, because it has capitalized on improved coil designs, registers higher RF penetration and offers lower signal-to-noise ratios. This paper is a discussion of the advantages of using higher magnetic fields in imaging, and the challenges of shifting to higher magnetic fields, drawing from the operational characteristics of nuclear spin.
Discussion
The advantages of using higher field imaging include the realization of a higher signal-to-noise quotient, as opposed to the earlier field models, which offered inferior spectral resolutions for different applications.
This advantage is based on improving the model of the proton spin noise signal, placed in a highly tuned low-noise resonant, where there are varied magnetic field gradients, as the 3 Tesla model uses a high intensity magnet as well as a low one. As a result, there is a resultant modification of the projection-reconstruction protocol.
In many imaging instances, these areas of benefit impact positively, on the temporal or spatial resolution imaging, as compared to those previously realized using the older lower field systems.
The increased signal to noise ratio, further, leads to decreased acquisition durations and an increased space resolution. S.N.R. offers the opportunity for increased frequency between metabolite climaxes during spectroscopy, which serve as further improvements in the field of medical imaging.
Higher field imaging offers higher imaging quality, which is based on better contrast and noise resolution. The noise factor is normally, caused by the random movement of the electrons, ejected by the patient’s body and the detector coils. In the case of using higher field imaging, all other factors remaining constant, the intensity/ power of the signal resulting from a voxel is directly proportional to the voxel volume.
In such a case, SNR is equal to the volume of the voxel, multiplied by the square root of the signal acquisition duration. Therefore, these developments are employed towards decreasing the Volex volume, towards the improvement of spatial resolution so as to reduce the SNR levels registered. The spatial resolution factor reflects the sharpness of the images collected from the imaging system.
There is the advantage of chemical shift, which results from fractional shielding of the outer field, at the area of the nuclei – at the nuclei of the electron covering of the molecules. The shielding impact is related to the strength of the field, especially, that of the outer permanent magnet.
For instance, one impact is that the chemical shift taking place between methylene and water signals is the dominating signals from methylene and fatty acids, which total to an approximate level of 440 Hz at the 3 Tesla field in question. As a result, there in an improvement in spectral fat repression and spectroscopy, which are vital in magnetic imaging.
Based on this advantage, higher field magnetic resonance imaging allows for the effective imaging of aorta, heart, blood vessel and coronary arteries in an effective and speedy, non-invasive manner.
This has been made possible by the significant advances in gradient coil technology, a factor that creates better implementation of sequences, including “balanced steady state free precession.” This allows for faster imaging, increased spatial resolutions, speed and increase in imaging efficiencies.
Therefore, the model is effective in offering detailed imaging, which is useful in reflecting heart complications and coronary artery conditions. From using this higher field imaging models, medical specialists are able to determine the impacts of such conditions on the hearts and the organs surrounding the heart.
This is particularly the case, when trying to determine the thickness and the size of the different chambers of the heart, as well as establish the level of damage that may have resulted from progressive heart complications or persistent heart attack cases.
From this breakthrough, heart specialists are able to explain complications of the heart, distinguishing the conditions that need further corrective therapy through models like operation, recommending dietary changes, for instance, the call to reduce the intake of calories from fatty foods.
Higher field imaging offers highly detailed images from soft-tissue areas, especially, those around and near bone areas. This elevated projection-reconstruction protocol, makes it possible to realize an entirely non-invasive imaging of these opaque organs, at extremely increased levels of clarity, without the usage of x-rays or radio-frequency radiation, which can cause adverse effects.
Some of the areas that are effectively addressed by this higher field model include joint problems and spinal injuries. This advantage is of great significance, as it offers a model, from which comprehensive imaging of soft-tissues can be realized and administered, as opposed to the inability to offer such detailed imaging of these areas, which was not realized using lower field imaging.
From this strength, medical imaging specialists are able to address complicated conditions, these including sports-related injuries, particularly those that affect areas not fully addressed by low field imaging.
Higher field imaging has also risen to offer an effective replacement for the traditional model of x-ray mammography, which was used as a critical model for the detection of breast cancer at earlier development stages.
However, the model offers highly yielding benefits, as compared to the traditional x-ray model, as it does not expose the patients to the risk of exposure to radiations, which are attributed to the development of certain types of cancers.
The disadvantage of the earlier models of imaging, including x-rays are that, as a result of their high concentration of the energy stored, as well as the vast cross-section of their release, nuclear spin isomers present a threat, thus have attracted further interest towards research on administering models devoid of these defects.
In this regard, the higher field imaging model has offered an effective, time saving model, which can help medical specialists in detecting the incidences of breast cancer, without placing the patients at the risk of the adverse effects of continuous exposure to radiations.
The advantage of the model is that it is safe for the detection of sensitive areas, which may not be exposed to the radiations resulting from other diagnostic models like x-rays. These sensitive areas include the female and male reproductive organs and systems in general, the bladder and the pelvis.
Therefore, the new level of imaging has offered a highly effective, time-saving, risk-free model of diagnosing the problems of highly sensitive organs, which can be administered as frequently as possible, as it presents no risk to the recipients of the therapeutic services.
The challenges of going to higher fields in medical imaging include that the model does not accommodate the diagnostics of people with cardiac pacemakers, as it may cause them fatal effects, due to the interference between the magnetic field of the imaging system and certain components of the pacemaker.
The effects result from the likely magnetic field interference, including the effects of heating, reed-switch closure due to the high magnetic field, as well as the stimulation or impact of sensing ability, which results from the gradient fields used in higher field imaging. As a result, the technology presents the challenge of not being able to address the medical diagnostic needs of these excluded groups.
However, these groups may be covered by the therapy, after it has been taken through some innovative development or after the adoption of protective measures to protect such patients. Other groups that cannot be exposed to this diagnostics model include pregnant women, and the patients using brain and aneurism clips.
The effectiveness of higher radiation imaging is affected by certain clothing, especially those that have metallic objects and patients who have used certain make-up compounds, which contain metal particles, as these can ruin or degrade the quality of the images collected.
One major challenge with the usage of the higher field imaging technology is that the patients undergoing diagnosis, are required to lie down inside the cylinder-like room at the machine, which may be uncomfortable for many; relaxation kinetics development.
This ineffectiveness is mainly because; the new higher field models are created to offer imaging postures, where the object under imaging is as close as possible to the detection coils, as this increases the level of sensitivity, thus clearer images.
These detection coils are responsible for absorbing and re-emitting the field radiation, thus must lie close to the object being imaged, though the proximity may be varied depending on the strength of the field and the magnetic properties of the functional isotopes.
The niobium titanium superconductor materials used to engineer the higher field imaging systems are limited to certain levels of the magnetic fields, which can be produced by the systems, mainly because of the critical field variation of these semiconductor materials. This challenge draws from the response by the overall magnetization of the nuclear spins, as exploited under magnetic resonance imaging.
As a result, the challenge of limited field abilities should be resolved by improving on the semiconductor technology, so that maximum benefit can be drawn from the model.
However, this challenge is likely to affect the technology further, as attempts to increase the strength of the fields, will come with corresponding increment in cryogen consumption, weight of the machinery and concerns regarding perimeter fields for sitting. Weight in particular, can be an issue, despite the developments to install principal passive shielding.
In the area of safety, major challenges come in the way of ferromagnetic projectiles, heightened electromagnetic effects and heightened torques on medical implants and devices. One major engineering challenge remains the shift towards producing high-strength, homogenous transmission of B1 magnetic fields, and still manages to maintain the regulatory guidelines to be met, with reference to tissue power outlook.
Conclusion
Tesla, whose symbol is T, is the SI unit for magnetic flux intensity. In the field of technical magnetic resonance imaging, Tesla is the unit of measure for computing the power of a magnetic field. Before the shift to the usage of 3 Tesla power systems, 1.5 Tesla power systems were used.
3 Tesla systems offer twice the strength of the previous systems, and present up to 10-15 times the power of open MRI scanning systems. 3 Tesla imaging systems offer increased image clarity, which is highly effective for pathological situations of the spine, musculoskeletal systems and international organs. The system is also effective, in terms of diagnostics durations, improved patient comfort and high image clarity.
The advantages of using higher field imaging include higher signal-to-noise ratio, and comprehensive imaging of soft tissues, especially those around bone areas like joints. The model offers a risk-free replacement of x-ray technology in detecting cancers like breast cancer, and the fact that it is radiation-free.
The challenges of shifting to higher fields imaging include that it cannot be used with patients using cardiac pacemakers and women who are pregnant.
The shift to the new technology is also challenged by the interference caused by metals and metal particles, the comfort concerns among many users of the service, and the inability to balance the magnetic fields and the effect it imposes on the health of the patients. The model is also challenged by the semiconductor used, which is affected by its critical field variation.
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