To overcome the need to look at two separate diffusion image sets, in 1998 Jim Provenzale and colleagues proposed using an exponential image, which was simply the b0 image divided by the conventional DW image. Algebraically
The automatic generation of exponential diffusion images is now possible on many brands of scanners. I personally don't use exponential images routinely (except for brain MRI in neonates and young infants where I find it helpful because of the intrinsically high water content and T2 signal in this age group). Because the exponential image is a calculated map, like the ADC map it is often of lower quality than the DW image. So I feel I cannot give up inspecting the DW image especially when searching for small lesions like brainstem infarctions where the additive contrast effects of prolonged T2 plus restricted diffusion are helpful. If you don't have an exponential image available, a reasonable alternative is to simply invert the conventional ADC map on your monitor.
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In theory the exponential ADC map should give superior lesion-to-background contrast compared to an inverted ADC map. This is because the conventional ADC map is based on the logarithm of SDWI/So while the exponential image is based solely on the ratio SDWI/So. The logarithm in the ADC calculation attenuates some of the contrast differences making it inferior in theory.
Provenzale JM, Engelter ST, Petrella JR, et al. Use of MR exponential diffusion-weighted images to eradicate T2 “shine-through” effect. AJR Amer J Roentgenol 1998; 172:537-539.