Regional and directional anisotropy of apparent diffusion coefficient in rat brain

✍ Scribed by Mathias Hoehn-Berlage; Manfred Eis; Bernd Schmitz

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 855 KB
• Volume: 12
• Category: Article
• ISSN: 0952-3480
• DOI: 10.1002/(sici)1099-1492(199902)12:1<45::aid-nbm545>3.0.co;2-6

✦ Synopsis

Quantitative diffusion maps were recorded in normal rat brain. In multi-slice sections covering the whole brain, strong variation of the apparent diffusion coefficient (ADC) was observed depending on slice position at constant gradient direction. Furthermore, a varying difference between apparent diffusion coefficients depending on gradient direction was found, reaching 32% in the cortex of the ventral-most horizontal sections while showing equal ADC on the dorsal cortex side. The regional variation and directional anisotropy of the ADC was not restricted to white matter but was described for both cortical and subcortical brain tissue. From diffusion coefficients along the three major field gradient directions (ADC x , ADC y , ADC z ), the average ADC (ADC average ) was determined from the trace of the diffusion tensor (D) as 653 AE 28 mm 2 /s for parietal cortex and 671 AE 32 mm 2 /s for lateral cortex, independent of position along the sagittal direction. From these observations about the regional diffusion anisotropy, a more stringent protocol for the description of ischemic ADC changes is proposed.