MRI: An Imperfect Gold Standard
Sep 26th, 2022
In 1981, magnetic resonance imaging, or MRI, was used for the first time to view the brain of a patient with multiple sclerosis. Compared to the previous standard of diagnosing MS through lumbar puncture, MRI provided a major technological advance. Using MRI, healthcare providers were able to non-invasively visualize brain and spine lesions for purposes of diagnosing and for tracking MS progression. Since that first scan, MRI has developed into the most important tool to diagnose and monitor multiple sclerosis.
Forty years later, MRI is still considered the gold standard for the diagnosis and monitoring of MS. However, despite its important role in helping health care providers and their patients manage MS, over time we have discovered that MRI and the ways in which results are read and interpreted have limitations. Below are a few factors that can impact the quality and interpretation of MRI scans.
Radiologist expertise. Given the extensive training of radiologists, it may come as a surprise that radiologist expertise plays a large role in the way in which MRI findings are interpreted and reported. In fact, a recent study showed that the quality of MRI information provided to the ordering health care provider varied by both the center at which the image was scanned as well as the specific radiologist reporting. This variability is further confirmed in a study that followed a single patient with lower back pain who was imaged at 10 different MRI centers over a three-week period. Across the 10 centers, there were 49 distinct findings on the scans, none of which appeared across all reports. A different study showed that radiologists specialized in neurology produced reports with higher sensitivity, higher negative predictive value and lower false-negative rates in the detection of new MS compared with radiologists who were not specialized in neurology.
Financial considerations. Another consideration around MRI interpretation quality is the amount of time the radiologist may have available to read each report. MS MRI scans require extensive effort and time-consuming reporting documentation, particularly if the patient has severe disease. Compared to scans assessing stroke or trauma, MS scans are very complex; yet current reimbursement rates for brain MRIs are the same regardless of which condition is being assessed. This reimbursement structure creates financial and market pressures that may compress the amount of time available to radiologists to allocate to reading and interpreting MS brain scans.
Machine quality. Compounding the situation, MRI machines are not uniform in quality and can vary based upon signal strength (e.g., 1.5T vs 3.0T) and other options selected at the time of purchase. Even machines that produce higher-quality images carry limitations related to unintended image artifacts that can appear on the scans. The age of the MRI machine and how regularly it undergoes routine maintenance can impact image quality as well.
MRI reporting. Finally, the lack of a universal reporting standard has been shown to have a real impact on how neurologists practice medicine. Each radiologist has flexibility to deliver reports for MS patients according to their own preferences. While some results are reported in a structured format with required fields for a variety of MS-specific parameters, other reports are unstructured, even delivered in prose, requiring ordering physicians to search for information of note. One study demonstrated that neurologists understood lesion load more frequently when reading structured reports compared to reading unstructured reports. Additionally, the impact of unstructured reports has been correlated with an exacerbated “status quo bias,” which suggests that neurologists are inclined to “stay the course” regarding treatment decisions when faced with difficult-to-interpret MRI reports, rather than explore a potential treatment modification.
While MRI remains an important tool in the management of MS, we at Octave believe that it can be done better – and that MS patients deserve better. Our MRI Insights Program provides enhanced analytics, MS-specific imaging protocols and standardized reports that offer essential disease activity and progression details over time.
Keep an eye on this space to learn more about how we plan to address the needs of healthcare providers and their patients to help them live more harmonious lives.