Vessel size imaging

✍ Scribed by Irène Troprès; Stephan Grimault; Albert Vaeth; Emmanuelle Grillon; Cécile Julien; Jean-François Payen; Laurent Lamalle; Michel Décorps

• Book ID: 101385557
• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 318 KB
• Volume: 45
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/1522-2594(200103)45:3<397::aid-mrm1052>3.0.co;2-3

✦ Synopsis

Vessel size imaging is a new method that is based on simultaneous measurement of the changes ⌬R 2 and ⌬R* 2 in relaxation rate constants induced by the injection of an intravascular superparamagnetic contrast agent. Using the static dephasing approximation for ⌬R* 2 estimation and the slow-diffusion approximation for ⌬R 2 estimation, it is shown that the ratio ⌬R 2 / ⌬R* 2 can be expressed as a function of the susceptibility difference between vessels and brain tissue, the brain water diffusion coefficient, and a weighted mean of vessel sizes. Comparison of the results with 1) the Monte Carlo simulations used to quantify the relationship between tissue parameters and susceptibility contrast, 2) the experimental MRI data in the normal rat brain, and 3) the histologic data establishes the validity of this approach. This technique, which allows images of a weighted mean of the vessel size to be obtained, could be useful for in vivo studies of tumor vascularization.