Imaging Cerebral Microbleeds Using Susceptibility Weighted Imaging: One Step Toward Detecting Vascular Dementia

The MRI Institute for Biomedical Research, Detroit, Michigan, USA.
Journal of Magnetic Resonance Imaging (Impact Factor: 3.21). 01/2010; 31(1):142-8. DOI: 10.1002/jmri.22001
Source: PubMed

ABSTRACT

To monitor changes in the number of cerebral microbleeds (CMBs) in a longitudinal study of healthy controls (HC) and mild-cognitively impaired (MCI) patients using susceptibility weighted imaging (SWI).
SWI was used to image 28 HC and 75 MCI patients annually at 1.5 Tesla over a 4-year period. Magnitude and phase data were used to visualize CMBs for the first and last scans of 103 subjects.
Preliminary analysis revealed that none of the 28 HC had more than three CMBs. In the 75 MCI patients, five subjects had more than three CMBs in both first and last scans, while one subject had more than three bleeds only in the last scan. In five of these six MCI patients, the number of CMBs increased over time and all six went on to develop progressive cognitive impairment (PCI). Of the 130 total CMBs seen in the last scans of the six MCI cases, most were less than 4 mm in diameter.
SWI can reveal small CMBs on the order of 1 mm in diameter and this technique can be used to follow their development longitudinally. Monitoring CMBs may be a means by which to evaluate patients for the presence of microvascular disease that leads to PCI.

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Available from: Wolff M Kirsch, Dec 17, 2013
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    • "However, visual screening is time-consuming, subjective and has low reproducibility between observers [6]. Moreover, it is prone to errors as small CMBs can be easily missed, or mistaken for vessel cross-sections, especially in MR Susceptibility Weighted Imaging (SWI) due to the high sensitivity of this sequence to magnetic susceptibility [7]. "
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