Abstract 12629: Estimation of Microglia Activity in Hemorrhagic Stroke- A New MRI Post Processing Technique
Objective: Non-invasive monitoring of microglia/macrophage activity would be valuable to clinicians treating patients with intracerebral hemorrhage (ICH). We developed a Magnetic Resonance Imaging (MRI)-based technique capable of tracking brain microglia activity after ICH.
Background: During ICH, erythrocytes released from the vasculature into the brain matter are cleared from the cerebral parenchyma by microglia. Heme released during this process is metabolized by heme oxygenase to biliverdin, carbon monoxide, and pro-oxidative iron. Oxidative stress appears to play a prominent role in ICH pathogenesis and free radical scavengers have been shown to significantly reduce brain injury in animal models of ICH. Non invasive monitoring of microglia activity would help assess response to therapy with free radical scavengers in ICH.
Methods: MR images of 6 ICH patients were used for this study at two different time intervals from the occurrence of the stroke. Isotropic T1 or T2-weighted images with 3 mm3 spatial resolution were used for this work. Clinical exams were acquired on 3.0 T scanners (GE, DVMR 20.1IB, Milwaukee, WI). The hematoma region was segmented and reconstructed for high resolution isotropic volume through cubic spleen interpolation to extract the inner details from the isotropic T2W volumetric images of these stroke patients using 3D Volumetric analysis tool combined with other modules of Analyze 11.0 software (Analyze 11.0; Biomedical Imaging Resource, Mayo Clinic, Rochester, MN).
Results: Image below shows the schematic representation of high resolution segmented hematoma region at days 3 and 18 from the onset of stroke, in two age and sex-matched ICH patients. Visible are the black patched/dotted regions corresponding to microglia activity, which was observed to increase over time from the onset of stroke.
Conclusion: This novel MRI post processing technique would aid clinicians in assessing response to therapy in ICH stroke patients.
- © 2013 by American Heart Association, Inc.