Magnetic resonance imaging, also known as MRI, nuclear magnetic resonance or NMR, is a diagnostic imaging technique. Here, the equipment, known as an MRI scanner, uses magnetic fields and radio waves to create detailed images of the human body’s interior without the need for invasive procedures.
This procedure involves the person being examined entering a device that generates a powerful magnetic field, emitting radiofrequency pulses. These pulses cause the hydrogen nuclei found in our body to emit a type of signal, which is detected by the device’s scanner. This creates images of the body’s tissues, organs, and structures.
What is MRI for?
There are many reasons why a doctor might request that a patient undergo one or more MRIs, but what is the real purpose of an MRI?
- Diagnosis: is a tool frequently used to diagnose different diseases or medical conditions. This allows for the determination of the condition of soft tissues, the presence of neurological disorders, joint problems, tumors, or vascular diseases.
- Assessment: Thanks to its characteristics, MRI is beneficial for visualizing soft tissue; an MRI can be performed on the brain, spinal cord, muscles, or any other internal organ. The image provides detailed information on the anatomy and function.
- Planning: The information provided by an MRI enables planning and guiding various medical and surgical treatments. Doctors use imaging to locate affected areas precisely, analyze the extent of the injury or disease, and determine the most effective treatment strategy.
- Follow-up: After treatment, MRI can be used to monitor and assess the progression of chronic diseases or long-term medical conditions. With MRI images, doctors can monitor a patient’s response to treatment and adjust their treatment plans accordingly.
For all these reasons, MRI is a versatile tool that will benefit the patient.
T1 and T2 MRI
Magnetic resonance imaging uses different imaging sequences, which are specific sets of parameters for radiofrequency pulses, enabling the enhancement of specific aspects of the tissues being examined.
The T1 and T2 imaging sequences are frequently used.
- Longitudinal relaxation time / T1: T1 refers to the time it takes for hydrogen nuclei to realign with the magnetic field after being disturbed by the pulse. In the T1 sequence, tissues such as fat appear bright, while tissues like muscle appear darker; this sequence is generally used to visualize structural anatomy.
- Transverse relaxation time / T2: T2 refers to the time it takes for protons to lose their phase coherence after being disturbed by the pulse. Within T2 images, tissues such as fluids appear brighter, while tissues like bone marrow appear darker. T2 sequences are often used to visualize fluids or pathologies involving inflammation.
Both T1 and T2 MRIs provide complementary information about the composition and pathology of tissues in the body.
Can MRI be performed if you have nails?
Because MRIs use high-power magnets, it’s essential to follow the safety precautions instructed by the technicians. Although each location may have more or fewer instructions, all of them request that metal objects not be placed inside the room where the test is being taken.
This includes watches, jewelry, hearing aids, eyeglasses, clothing with metal inserts, dentures, and other similar items. For this same reason, the feasibility of performing the test may be questionable if the patient has nails or other similar devices.
Generally speaking, nails or other implants do not necessarily exclude a person from this study; however, it is vitally important to discuss with your specialist and doctor any situation that may interfere with the test.
For example, you should list any surgical procedures you have performed, oral treatments, medical devices you have, or any implants.
With complete information, it will be possible to determine whether MRI is an appropriate procedure, and if there is a potential risk, necessary precautions can be taken.
Types of MRI
As a versatile tool, MRI is used in a wide variety of clinical situations; it is frequently needed in:
- Musculoskeletal injuries: It allows for the diagnosis of injuries in soft tissues, joints, ligaments, bones, and tendons.
- Neurological diseases: It is essential in the evaluation and diagnosis of diseases of the central or peripheral nervous system, allowing the identification of brain tumors, multiple sclerosis, movement disorders, cerebrovascular events, and more.
- Spinal pathologies: In the spine, it helps in the evaluation and diagnosis of spinal stenosis, bone marrow compression, herniated discs, and other conditions.
- Pelvic and abdominal disorders: Assists in the diagnosis of diseases affecting organs in this region, such as the kidneys, pancreas, and liver, including the detection of vascular disorders, the presence of tumors or cysts, and inflammation.
- Cardiovascular diseases: Magnetic resonance imaging (MRI) assesses the function and structure of the heart, detecting conditions such as congenital heart disease, heart valve disease, and cardiomyopathy.
- Breast pathology: This is a tool that allows for the detection, characterization, and staging of breast tumors or the evaluation of breast implants.
- Joint disorders: diagnoses diseases or injuries of the joints, including osteochondritis, osteoarthritis, cartilage or joint injuries; a standard procedure is a knee MRI.
The range of situations in which an MRI is required are very broad; however, the specific decision to perform this test will depend on the clinical evaluation of each patient, as well as the specialist’s needs to meet the individual’s health goals.
Magnetic resonance imaging (MRI) allows for the precise detection of changes in organs, tissues, and internal structures, making it a safe and effective method for diagnosis. However, it is common that complementary tests such as computed tomography, X-rays, encephalogram or nuclear medicine tests are required depending on the characteristics of each patient and their possible pathology.
At ABC Medical Center’s Department of Radiology and Molecular Imaging, we can provide you with specialized care. Contact us!
Fuentes:
MedlinePlus, MSD Manuals, Cancer.org
