Incidental Findings Are Frequent in Young Healthy Individuals Undergoing Magnetic Resonance Imaging in Brain Research Imaging Studies: A Prospective Single-Center Study

Abstract Objectives This study aimed to examine the alterations in magnetic resonance imaging (MRI) characteristics of bioabsorbable magnesium (Mg) screws over time in a single center study in humans. Methods Seventeen patients who underwent medial malleolar (MM) fracture or osteotomy fixation using bioabsorbable Mg screws and had at least one postoperative MRI were included in this retrospective study. Six of them had more than one MRI in the postoperative period and were subject of the artifact reduction measurements. 1.5T or 3T MRI scans were acquired in different periods in each patient. The size and extent of the artifact were assessed independently by two experienced radiologists both quantitatively (distance measurement) and qualitatively (Likert scale). Results In the quantitative measurements of the six follow-up patients the screw’s signal loss artifact extent significantly decreased over the time, regardless of the MRI field strength (p<0.001). The mean artifact reduction was 0.06 mm (95% confidence interval [CI]: 0.05–0.07) for proton density weighted [PDw] and 0.04 mm (95% CI: 0.03–0.05) for T1 weighted (T1w) sequences per week. The qualitative assessments similarly showed significant artifact reduction in all MRI sequences. Different imaging findings, like bone marrow edema (BME), liquid collections, and gas formation were reported. The overall inter-reader agreement was high (κ=0.88, p<0.001). Conclusions The time-dependent artifact reduction of Mg screws in postoperative controls might indicate the expected self-degradation of the Mg implants. In addition, different MRI findings were reported, which are characteristic of Mg implants. Further MRI studies are required to get a better understanding of Mg imaging properties.

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Incidental Findings in Magnetic Resonance Imaging (MRI) Brain Research

The Journal of Law Medicine & Ethics ◽

10.1111/j.1748-720x.2008.00275.x ◽

2008 ◽

Vol 36 (2) ◽

pp. 315-319 ◽

Cited By ~ 22

Author(s):

Charles A. Nelson

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Incidental Findings ◽

Brain Research ◽

The Body ◽

7 Tesla ◽

X Rays ◽

Resonance Imaging ◽

Imaging Tool ◽

Magnetic Resonance Imaging Mri

Magnetic resonance imaging (MRI) is a noninvasive imaging tool that utilizes a strong magnetic field and radio frequency waves to visualize in great detail organs, soft tissue, and bone. Unlike conventional x-rays (including computed tomography [CT]), there is no exposure to ionizing radiation and at most field strengths (generally below 7 Tesla) the procedure is considered safe for nearly every age group. Because it is non-invasive (i.e., does not break the skin or harm the body) and possesses excellent spatial resolution (down to millimeters), the use of MRI as a research tool has increased exponentially over the past decade. Uses have ranged from add-ons to a clinical study (e.g., after scanning a child who has fallen from a bicycle, the radiologist might do an extra sequence to explore ways of obtaining higher resolution images) to studies of brain development in typically developing children. In addition, a major effort has been made in recent years to use MRI to study brain function (so-called “functional MRI” [fMRI]). Because the clinical utility of fMRI has not yet been realized, fMRI is still considered highly exploratory, and we cannot yet identify incidental findings of a functional (as opposed to structural) nature.

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