What Sequences on High-Field MR Best Depict Temporal Resolution of Experimental ICH and Edema Formation in Mice?

Mingchang Li,Ruth Thiex,Robert M Friedlander,Reza M Akhavan-Sharif,Rose Du

doi:10.1155/2012/961461

Abstract

Background and Purpose. Pilot study to examine the use of T1-, T2-, and T2*-weighted images for evaluating hematoma size and extent of edema in mouse brain at high field. Methods. Following collagenase-induced intracerebral hemorrhage, nine mice were imaged at 4.7 T using T1-, T2-, and T2*-weighted images for hematoma and edema quantitation on days 1, 3, 10, and 21 after surgery. Values were compared with morphometric analysis of cryosections at the time of final MR imaging. Results. For hematoma quantitation, the Spearman correlation coefficient (r) between T1 signal change and histology was 0.70 (P < 0.04) compared with r = 0.61 (P < 0.09) for T2*. The extent of perihematomal edema formation on cryosections was well reflected on T2 with r = 0.73 (P < 0.03). Conclusions. Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, thus laying the groundwork for longitudinal studies on hematoma resorption and edema formation.

Highlights

In humans, intracerebral hemorrhage (ICH) causes secondary damage in the brain through the induction of cerebral edema and perihematomal injury [1, 2]
Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, laying the groundwork for longitudinal studies on hematoma resorption and edema formation
The purpose of our pilot study was (i) to develop T1-and T2-weighted magnetic resonance imaging (MRI) protocols for highresolution studies of mouse brain in vivo which allow for the identification of hematoma and edema, and (ii) to perform a direct comparison of hematoma and edema volumes on MRI with morphometric studies on cryosections

Summary

Introduction

Intracerebral hemorrhage (ICH) causes secondary damage in the brain through the induction of cerebral edema and perihematomal injury [1, 2]. Various knockout mice have been bred to study the gene expression of the pro-oxidants heme [8] and ferrous iron [9], proteolytic enzymes such as metalloproteinases [10], thrombin [10], and inducible nitric oxide synthase [11], as well as leucocyte adhesion molecules (CD18) [12] in the perihematomal area. Their genetic variability has turned the mouse into a key study animal for intracerebral hemorrhage despite the small size of its brain. Within the limits of our pilot study, MR imaging on 4.7 T appears to approximate the temporal changes in hematoma and edema sizes in murine ICH well, laying the groundwork for longitudinal studies on hematoma resorption and edema formation

Methods

Results

Conclusion