Medical Equipment: MRI Machine
Over the past few years, technology has advanced significantly in almost all fields. The medical field has witnessed comprehensive technological advancement. It can be attributed to different factors, such as an increase in complicated diseases that call for comprehensive examinations and need for efficiency in medical operation. One of such products of technology in the medical field is the magnetic resonance imaging (MRI) machine. The equipment presents a lot of benefits to patients and the overall medical fraternity. MRI technology has advanced rapidly over the past few years. The current paper discusses the significance of MRI machine, the types of testing and preventive maintenance that can be used to keep the machine running properly, and any issues that can occur if proper preventive maintenance is not done. The paper also describes how the MRI machine is important to patients. The patient’s perspective is taken concerning the benefits of the MRI machine.
How the MRI Machine Works
For any feasible field strength, the energy difference is the range of radio frequency of the electromagnetic spectrum. To generate an image, pulses of radio-frequency have to be emitted by antennas that in turn excite the nuclear spin in the process of energy transition. As the spin is returning to its equilibrium point, they emit radio-frequency that possess a frequency dependent on the strength of the magnetic field produced. The radio frequency is very faint and as a result, it is received by the antennas, which are close to the object being imaged. When a known and precise gradient is created in the main magnetic field, which now contains additional radio frequency coils, the nuclei at different positions will tend to have different frequencies. Therefore, it becomes possible to compute the Fourier transform y extracting the different contributions of the different frequencies from the signal. Usually, a particular frequency corresponds to the signal emanating from water at a given location, referred to as a voxel. The image can then be reconstructed. Although the hydrogen protons in water are the main ones that are imaged, sodium, carbon, and phosphorous atoms are sometimes used in special operations.
Medical uses of MRI Machine
Neuroimaging
In conditions like neurological cancer, MRI machines are the investigative tools of choice. It is attributed to different factors, the most common being its ability to give better resolution as compared to CT. Additionally, MRI also offers a better visualization of the posterior fossa. The machine can provide a very clear contrast between the white matter and the grey matter of the brain. It makes it the best choice for many conditions that affect the central nervous system, such as dementia, epilepsy, infectious diseases, demyelinating diseases, and cerebrovascular diseases. For instance, imaging brain in dementing illness has been revolutionized over the past few years due to the presence of MRI machines. Neuroimaging contributes heavily to the diagnostic certainty of Creutzfeldt-Jakob and frontotemporal dementias. The greatest value of neuroimaging is witnessed during therapeutic trails. The traditional methods relied heavily on clinical assessments of behavior and cognition. However, these assessments proved to be inherently variable from day to day and from examiner to examiner. However, volumetric MRI is likely to become the principle outcome measure in clinical trials.
During neuroimaging, many images can be taken within a span of milliseconds. As a result, such images can show how the brain responds to different stimuli. It can allow researchers to study both the structural as well as the functional abnormalities of the brain in case of psychological disorders. It is essential in improving the general well-being of the patients, especially those suffering from psychological disorders. MRI machines are also used heavily in MRI-guided radiosurgery as well as stereotactic surgery during treatment for arteriovenous malformations, intracranial tumors, and any other surgically treatable conditions by making use of a device referred to as N-Localizer.
Cardiovascular Imaging
Gastrointestinal and Liver Imaging
Muscular-skeletal imaging
Some applications of MRI machines in musculoskeletal systems include soft tissue tumors, assessment of diseases in joints as well as spinal imaging.
Functional magnetic resonance imaging
Ideally, functional MRI is applied when an understanding of how the different parts of the human brain respond to passive activity or external stimuli when in a resting state is desired. Functional MRI has wide applications in cognitive and behavioral research. It is also very useful when planning neurosurgery in the eloquent brain areas. Hemodynamic responses to transient neural activity, which occur because of a change in the ratio of deoxyhemoglobin and oxyhemoglobin can be measured by blood oxygenation level dependent functional magnetic resonance imaging.
Oncology
Benefits of MRI machines
As a patient, there are so many benefits derived from the use of MRI machines in the medical operations. A closed cylindrical MRI machine can provide quality images for the right clinical situation and the right patient. However, in some situations, open MRI scanners can provide more superior images where the closed MRI scanners would fail to do so. Additionally, open MRI examination is in a better position to offer more patient safety as compared to the closed MRI. Open MRI machines also offer another benefit to the patients in the sense that they can accommodate a high number of patients. The following are the main benefits that MRI machines offer to patients.
It is attributed to the fact that the MRI machines allow imaging techniques that do not require the use of x-rays. As a result, the patients are not exposed to the ionizing radiations. Patients always prefer diagnosis that does not expose them to substantial amounts of ionizing radiations. It makes the MRI machine to be preferred by most patients. Hence, the MRI machines become alternative to CT scans, X-ray, and angiography when diagnosing patients problems that pertain to blood vessels and the heart.
Can Diagnose Wide Range of Conditions
Clearer Images for the Body’s Soft Tissue Structures
Soft tissue structures in the human body, such as liver and the heart, require accurate characterization and identification. MR images can give such required precision. Additionally, the fact that the MRI machines do not expose patients to ionizing radiations also makes it the best option in assessments of these soft tissues in the body. Such characteristic of the MRI images also makes it the best alternative tool when performing early diagnosis as well as evaluation of focal tumors and lesions. Hundreds of images can also be created in any orientation and from virtually any direction of the body.
Less Allergic Reactions
The contrast material that is used in MRI examinations is less likely to lead to allergic reactions as compared to other iodine-based contrast materials which are used in the conventional CT scanners and X-ray tubes. As a result, even the patients who are very vulnerable to allergic conditions can be examined with ease and without fear.
The use of MRI machine is on the rise, which means the number of adverse incidents related to MRI may increase as well. Even one adverse event in medical practice should not be allowed as it presents a risky situation to the patients. Any healthcare provider must be committed to implementing a comprehensive MRI safety program. It is critical to achieving zero tolerance to MRI errors. Such a safety program is also essential in ensuring that the MRI machines run properly.
There are two main features of magnetic fields and which act as the major sources of the most MRI incidents; the projectile effect and translational attraction. The projectile effect, also referred to as missile effect, occurs when ferrous materials, such as most stainless steel and nickel alloys are not compatible with the environment under which the MRI machine is placed. In case the ferrous based materials are exposed to the very strong magnetic field, they are pulled violently towards the source of the magnetic fields. On the other hand, translational attraction occurs when one point of an anatomy in a magnetic field is attracted further than the anatomy’s furthest point from the source of attraction. The effect of this differential is to create a more forceful attraction, which in turn makes the object placed in the MRI to move towards the source of magnetic effect at a higher speed.
Training of all nursing staff and technologists should be done. The medical director should periodically review the safety protocols concerning MRI machines. It is very important, especially after a significant change in the MRI suite environment. Such changes should be incorporated into the training program aimed at ensuring that the practitioners are equipped thoroughly to use the machines effectively and to keep them running properly. There should be an MRI safety officer who is mandated with the responsibility of ensuring that all safety procedures and policies are followed strictly.
Safety Check
Before a patient or even a member of the support staff is allowed to enter the scan room containing the MRI machine, he or she should be thoroughly scanned for any metallic objects. It should be so not only for the external metallic objects but also for the internal metallic implants as well. In some instances, patients may have implants in their bodies, which may make it very dangerous for them in case they are exposed to very strong magnetic fields like the ones generated in the MRI machines. For instance, metallic fragments contained in the eye are extremely dangerous because a little movement of these fragments may cause blindness or eye damage to the patients. A 25-year-old metallic fragment in the eye is just as dangerous now as it was during its initial states. Additionally, people who have pacemakers should not be exposed to the MRI scanners as an exposure to the machine may cause the pace makers to malfunction. Aneurysm clips found in the brain may be dangerous if exposed to the strong magnetic field as these magnets may move them, which in turn causes them to treat the artery they were placed on for repair. Some dental implants are magnetic as well. However, most orthopedic implants, although they are ferromagnetic, are okay because they are firmly embedded in the bones. Scanning for all these objects is of great help to the patients as well as helping the machines to run properly. In case, some materials are found, and which offer a risky situation, other imaging techniques may be preferred.
If the above safety guidelines are not followed, the MRI machine can expose significant hazards to both the patients and the healthcare providers. Ideally, these hazards can be categorized into translational forces, which entail exposure to incompatible objects and torque forces, which run in the parallel direction to the translational force, and patient discomfort. The torque forces significantly create conditions that are life-threatening to patients, especially those who have medical implants.
Conclusion
Bibliography
Pichler, Bernd J., Martin S. Judenhofer, and Hans F. Wehrl. "PET/MRI hybrid imaging: devices and initial results." European Radiology 18, no. 6 (2008): 1077-1086.
RadiologyInfo.org: Magnetic Resonance Imaging (MRI) – Body. 2016
Willis HRH. Magnetic Resonance Imaging Hazards and Safety Guidelines: Strategic Outcomes Practice, Technical Advisory Bulletin. 2009
Zhang et al. The Role of Endorectal Coil MRI in the management of patients with prostate cancer and in determining radical prostatectomy surgical margin status: A report of a single surgeon's practice (2007)
