What is an MRI? Understanding Magnetic Resonance Imaging

December 12, 2023

patient going into MRI machineMagnetic Resonance Imaging (MRI) is a non-invasive diagnostic test that produces detailed and accurate images of the internal body structures, including bones, organs, and tissues. This technology is widely used to diagnose medical conditions and injuries. In this article, we will explore what MRI is, how it works, and its uses in the medical field.  

How does an MRI scan work?

An MRI scanner is a large tube-shaped machine that creates a strong magnetic field around the patient. Powerful magnets and radio waves are used to create detailed images of the internal body parts, such as soft tissues, bones, and organs. Contrast agents may be given to a patient intravenously before or during the MRI to help product clearer imagery. MRI differs from other imaging tests in that it does not use ionizing radiation like X-rays or CT scans.

What is an MRI used to diagnose?

MRI scans are commonly used to diagnose a wide range of medical conditions, including cancer, heart and blood vessel diseases, brain and nervous system disorders, and musculoskeletal injuries. They can also detect abnormalities in the liver, pancreas, kidney, and other internal organs. In addition, Magnetic Resonance Imaging scans can be used to guide doctors during surgical procedures, monitor the progress of treatments, and evaluate the effectiveness of medications.  

Benefits and Risks

One of the most significant advantages of MRI scans is that they provide highly detailed images of the internal structures of the body without exposing patients to ionizing radiation. They are also more accurate when viewing nerves, tendons, ligaments, and muscles and can detect smaller abnormalities that may be missed by traditional X-rays or CT Scans.   

Magnetic Resonance Imaging is generally considered a safe procedure, but it does involve some risks and potential side effects. Allergic reactions to the contrast dye can occur, as well as discomfort due to the loud noises generated by the scanner. MRI machines can also induce anxiety as the patient is in the confined space of the scanner for a period of time. Individuals who have advanced kidney disease, metallic implants, or cochlear implants may not be suitable candidates for this specific medical imaging procedure.  

How long does an MRI exam take?

MRI scans typically take between 30 minutes to one hour to complete. However, the duration of the exam can vary depending on the body part being examined and the complexity of the condition being investigated. Patients may be required to hold their breath briefly during the scan to minimize motion artifacts that can distort the images. To make the experience more comfortable, patients are often offered earplugs or headphones to reduce the noise generated by the scanner. 

Safety Standards and Products

To ensure compliance with MR safety standards, it is important to follow the guidelines set by the American Society of Testing and Materials (ASTM) International for marking MRI devices. By using specific symbols, you indicate the safety designation of products determined by independent organizations through thorough testing.   

  • MR-SAFE labels are applied to items that are completely free from any potential hazards of MRI scans. They have been extensively tested and verified, so they warrant the impeccable safety record they have been given. This label serves as a guarantee that these items can be relied upon without compromising the well-being of patients or the effectiveness of MRI Procedures.  
  • MR-UNSAFE designations are given to items that are identified as a significant threat or potential hazard when used in any MRI setting. This classification is crucial for ensuring the safety of both patients and staff. It helps prevent adverse reactions or complications that could arise from the presence of incompatible objects during magnetic resonance imaging procedures.  
  • MR-CONDITIONAL refers to medical devices that have undergone extensive testing to ensure their safety with specific Magnetic Resonance (MR) environments and under specific conditions of use. These devices have been assessed for their compatibility and potential risks when exposed to magnetic fields. This ensures patients and staff can confidently use them in certain MR settings to aid in accurate diagnoses and effective treatments.  

To facilitate the safe and efficient use of Magnetic Resonance Imaging technology, it is essential to have the right MRI Equipment and Supplies in place. By having the appropriate MRI Equipment, including scanners, coils, and contrast agents, healthcare providers can effectively perform accurate diagnoses and assessments.  

Additionally, having a reliable supply of consumables and accessories like gels, positioning aids, and sterile covers enhances the overall quality and effectiveness of MRI procedures. If you have questions about MRI scans or need to schedule an appointment, be sure to talk to your healthcare provider for more information. 


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