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What is the clinical and ethical importance of incidental abnormalities found by knee MRI?
Rebecca Grainger1, Stephen Stuckey, Richard O'Sullivan
1Department of Medicine, Wellington School of Medicine, University of Otago, 23A Mein St, Newtown, Wellington South 6021, New Zealand. rgrainger@malaghan.org.nz
Introduction:
Magnetic resonance imaging (MRI) is increasingly used to examine joints for research purposes. It may detect both suspected and unsuspected abnormalities. This raises both clinical and ethical issues, especially when incidental abnormalities are detected. The prevalence of incidental, potentially clinically significant abnormalities identified by MRI and their clinical significance in a population undergoing knee MRI in research studies are unknown.
Methods:
We examined the prevalence of such lesions in healthy asymptomatic adults and those with symptomatic knee osteoarthritis (OA) undergoing knee MRI with limited sequences for the purpose of research. The MRI findings in 601 asymptomatic subjects and 132 with knee OA who underwent at least one limited knee MRI scan for cartilage volume measurement were examined by an MRI radiologist for the presence of potentially clinically significant abnormalities.
Results:
These were present in 2.3% of healthy and 2.3% of OA subjects. All required further investigation to exclude non-benign disease, including four with bone marrow expansion (0.7%), requiring further investigation and management. A single potentially life-threatening lesion, a myeloma lesion, was identified in a subject with symptomatic knee OA on their second MRI scan in a longitudinal study.
Conclusion:
As musculoskeletal MRI is increasingly used clinically and for research purposes, the potential for detecting unsuspected abnormalities that require further investigation should be recognized. Incorporating a system to detect these, to characterize unexpected findings, and to facilitate appropriate medical follow-up when designing studies using this technology should be considered ethical research practice.
Insights
Magnetic resonance imaging (MRI) of the knee detects significant incidental abnormalities in 2.3% of healthy and osteoarthritis patients. Researchers should establish protocols for managing these unexpected findings in studies.
Area of Science:
- Radiology
- Medical Imaging
- Musculoskeletal Research
Background:
- Magnetic resonance imaging (MRI) is widely used in research for joint examination, potentially revealing unexpected abnormalities.
- The prevalence and clinical significance of incidental findings from knee MRI in research populations remain largely unknown.
- Detecting incidental abnormalities raises clinical and ethical considerations for research studies.
Purpose of the Study:
- To determine the prevalence of potentially clinically significant incidental abnormalities detected by limited-sequence knee MRI in research settings.
- To assess the clinical significance and management requirements of these incidental findings in both healthy and knee osteoarthritis (OA) populations.
Main Methods:
- Retrospective analysis of knee MRI scans from 601 asymptomatic and 132 symptomatic knee OA subjects.
- Limited MRI sequences were used, primarily for cartilage volume measurement in a research context.
- An MRI radiologist evaluated scans for potentially clinically significant abnormalities.
Main Results:
- Potentially clinically significant abnormalities were found in 2.3% of healthy subjects and 2.3% of OA subjects.
- Four cases (0.7%) of bone marrow expansion required further investigation and management.
- One potentially life-threatening myeloma lesion was identified in a symptomatic knee OA subject.
Conclusions:
- Musculoskeletal MRI, even with limited sequences for research, can detect unsuspected abnormalities requiring further investigation.
- Ethical research practice necessitates systems for detecting, characterizing, and managing unexpected findings from MRI studies.
- Recognizing the potential for incidental findings is crucial for designing and conducting responsible imaging research.
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