Multiple sclerosis or MS is a chronic disease of the central nervous system. MS is considered an autoimmune disease that causes damage to the insulating covers of nerve cells in the spinal cord and brain.
It’s estimated that over 1.8 million people worldwide suffer from this vile disease. And unfortunately, MS can’t be cured but it can be kept under control with early detection and treatment. And that’s where MRI (magnetic resonance imaging) comes into play.
In this article, we’ll explore the critical role of MRI in detecting MS, how the technology works, and what to expect during the diagnostic process.
What is MRI and how it works
MRI is a noninvasive medical scan that creates a detailed image of almost every organ and structure inside the human body, including the brain and spinal cord.
MRI scans have become essential in diagnosing and managing MS. However, unlike other medical imaging tests such as CT or X-ray, MRI doesn’t use radiation. It uses radiation-free magnets and radio waves to make clear images of the body structures.
Thanks to this technology, MRI can visualize lesions in the brain and spinal cord providing critical information.
Importance of MRI in MS diagnosis
Early detection
MRI can be very useful in detecting and early diagnosis of MS. These scans provide high-resolution images that help identify lesions or damage caused by MS.
Myelin, the protective fatty layer surrounding nerve fibers, naturally repels water. However, in MS, myelin is damaged and stripped away, leaving areas that retain more water. Depending on the type of scan used, these changes appear on an MRI scan as bright white spots or darkened regions.
This ability to detect subtle differences in tissue composition makes MRI an invaluable tool for identifying and monitoring MS lesions.
Sensitivity and specificity
MRI is widely regarded as the best tool for identifying MS lesions due to its exceptional sensitivity (94%) and specificity (83%) during the first year after an initial clinical event.
This advanced imaging technique can detect silent, asymptomatic lesions, which are pivotal in meeting the diagnostic criteria of dissemination in space and time, essential for confirming Multiple Sclerosis.
MS lesion characteristics
A lesion refers to an area of tissue damage in the brain or spinal cord. In the context of MS, lesions form when the immune system mistakenly attacks the myelin sheath, the protective covering around nerve fibers. This immune response leads to inflammation and subsequent scarring, a process known as sclerosis.
An MRI scan can identify specific types of MS lesions and show the difference between active and non-active lesions. Two common types of lesions related to MS are Dawson’s fingers and ovoid lesions.
The presence and distribution of these lesions help differentiate MS from other neurological disorders. Lesions in smaller regions of the central nervous system, such as the brainstem, spinal cord, or optic nerve, are more likely to cause noticeable signs and symptoms of MS.
Assessing risk after Clinically Isolated Syndrome (CIS) Diagnosis
MRI also plays a crucial role in the early detection of MS in patients experiencing Clinically Isolated Syndrome (CIS).
The scan of the number of lesions on the brain or spinal cord can provide valuable insights into the likelihood of experiencing a second attack and eventually being diagnosed with MS.
Additionally, an MRI can detect a second neurological event in individuals who may not exhibit any new symptoms, enabling an earlier and more accurate confirmation of an MS diagnosis.
Importance of MRI for monitoring disease progression
MRI is not only pivotal for the detection of MS but also for monitoring its progression. As mentioned, MS cannot be currently cured, but it can be managed and kept under control with treatment and careful monitoring of its progression.
Tracking lesion development
The neurologist will use MRI scans over time to track and compare new lesions’ development and assess treatments’ effectiveness. This ongoing evaluation supports informed adjustments to therapeutic strategies, ensuring the management plan remains effective and responsive to the patient’s needs.
Helps with prognosis
Certain types of lesions, particularly those located in the spinal cord, can serve as predictors of long-term disability outcomes in individuals with Clinically Isolated Syndrome (CIS) or early-stage Relapsing-Remitting Multiple Sclerosis (RRMS). These lesions are often associated with more severe disease progression and can guide treatment decisions.
Types and Purposes of MRI Scans for MS
Different types of MRI scans are used to assess the extent of the disease, monitor its progression, and evaluate treatment effectiveness.
Brain MRI
This type of MRI scan is the most commonly used type of MRI scan for diagnosing MS. This is because it allows easy detection of lesions that indicate damage to the myelin sheath. It is essential for confirming MS diagnosis, assessing disease activity, and identifying new lesions.
Brain MRIs are also used to monitor changes over time, guiding treatment adjustments.
Spinal Cord MRI
Doctors usually use an MRI of the spinal cord to detect lesions in areas that can directly influence motor and sensory functions.
Lesions in the spinal cord are often linked to severe symptoms and can provide valuable prognostic information regarding long-term disability in MS patients.
Contrast-Enhanced MRI
For this type of MRI, a contrast agent is used to highlight active inflammation within the brain and spinal cord.
It helps to differentiate between active and non-active lesions. This is important in identifying disease flare-ups and evaluating the effectiveness of treatment interventions.
Longitudinal MRI
As mentioned, MRI scans can help track disease progression by comparing new and previous scans. This approach allows doctors to assess whether a patient’s MS is active or in remission, and it informs decisions about treatment plans.
Bottom Line
As you can see, MRI scans play a crucial role in the detection and management of MS. These scans allow early detection and monitoring of disease progression and guide treatment decisions.
We hope that as technology advances, MRI’s ability to provide detailed insights into MS pathology will only continue to improve. At the same time, it will continue to enhance patient outcomes through timely intervention.
