Localized q‐space imaging of the mouse brain

Abstract

Localized q-space imaging was used to obtain water displacement profiles from mouse brain. These profiles take the form of unidirectional diffusive displacement probability distributions. Two groups of mice were studied, a normal group and a group in which surgery had been performed to produce a unilateral reduction in the supply of blood to the forebrain. q-Space measurements were made both in vivo and postmortem. The displacement profiles were characterized using the summary parameter prob[d < 10], which is the proportion of water molecules that undergo a net diffusive displacement that is less than ±10 μm, during the diffusion period (50 ms). The range of prob[d < 10] values in the normal group was 0.71 to 0.77 in vivo compared with 0.78 to 0.87 in the impaired hemisphere of the surgically treated group. An increase in prob[d < 10] occurred postmortem to yield values in the range 0.79 to 0.81 and 0.80 to 0.89 in the normal and surgically treated group, respectively. These observations are consistent with the diffusion-weighted image intensity changes that occur after a period of ischemia.