To provide a review of the MRI physics of diffusion weighted imaging (DWI).
To illustrate current utilities of diffusion weighted imaging (DWI).
To highlight the expanded scope of practice in abdominal and pelvic imaging.
DWI harnesses the erratic motion of water molecules to generate image contrast.
Well-established uses of DWI include differentiating benign from malignant lesions,
detecting and characterising disease activity in the context of inflammatory bowel disease.
Apart from these common utilities,
we explore the scope for DWI in the context of the most common abdominal and pelvic pathologies a trainee radiologist may encounter.
Findings and procedure details
Brownian Motion and Diffusion
also known as diffusion,
describes the random motion of water molecules due to thermal energy.
Diffusion weighted imaging harnesses the diffusion characteristics of water molecules in order to generate signal contrast.1
Table 1: Key definitions in diffusion2
Equal probability of movement in all directions
Variable probability of movement in all directions
The motion of water molecules may be 'free' or 'restricted',
depending on: distribution between intra and extracellular compartments,
barriers such as cell membranes and...
DWI has a multitude of common utilities therefore the need to increase understanding amongst trainee radiologists is essential to ensure we utilise this imaging sequence to its fullest capacity.
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Diffusion MRI : Theory,
Oxford University Press,
Technical aspects of diffusion imaging of the body.Eur J...