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Updated: Jun 6, 2026
17:06
Co-analysis of Brain Structure and Function using fMRI and Diffusion-weighted Imaging
Published on: November 8, 2012
[The effect of the surroundings to the apparent diffusion coefficient on diffusion weighted imaging]
Yuya Yamatani1, Tsukasa Doi, Kozo Shimizu
1Central Division of Radiology, Nara Medeical University Hospital, Japan.
Nihon Hoshasen Gijutsu Gakkai Zasshi
|November 10, 2010
Summary
Diffusion weighted imaging (DWI) measures water diffusion using apparent diffusion coefficient (ADC) values. Surrounding materials, like iron oxide, can decrease ADC values, potentially underestimating tumor diffusion in MRI scans.
Area of Science:
- Magnetic Resonance Imaging
- Diffusion Weighted Imaging
- Quantitative MRI
Context:
- Apparent diffusion coefficient (ADC) values are crucial for tumor diagnosis in MRI.
- The influence of surrounding materials on ADC values remains under-investigated.
- Superparamagnetic iron oxide (SPIO) nanoparticles are used in MRI contrast agents.
Purpose:
- To investigate the impact of surrounding materials on ADC measurements.
- To quantify changes in ADC values based on the density of superparamagnetic iron oxide (SPIO).
Summary:
- A sealed phantom was used to measure ADC values with varying SPIO concentrations in the surroundings.
- Results demonstrated a decrease in ADC values correlated with increased SPIO density.
- This indicates that surrounding hemorrhage or iron deposits can affect tumor ADC values.
Impact:
- Findings suggest that surrounding paramagnetic materials can lead to under-estimation of tumor ADC values.
- This has clinical implications for accurate tumor characterization and differential diagnosis using DWI.
- Further research is needed to account for these environmental effects in clinical MRI interpretation.
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