Related Experiment Videos
Magnetization transfer MRI: application to treatment of middle cerebral artery occlusion in rat
Q Jiang1, J R Ewing, Z G Zhang
1Department of Neurology, Henry Ford Health Sciences Center, 2799 West Grand Boulevard, Detroit, Michigan 48202, USA.
Abstract:
The temporal profiles of MRI parameters which use quantitative estimates of magnetization transfer were measured in 22 male Wistar rats subjected to middle cerebral artery occlusion, with and without therapeutic intervention with an anti-ICAM-1 monoclonal antibody. Two measures were used: the value of a magnetization transfer-related parameter in a predetermined region of interest, and the area of damage, as measured by changes in this parameter. In both groups, the value and area of damage of the inverse of the apparent forward transfer rate for magnetization transfer (1/k(fa)) significantly increased from the preischemic values (P < 0.05), as did T1 under an off-resonance partial saturation of the macromolecular pool (T1sat), and T1 (P < 0.05). Moreover, the increase in the value and total area of damage, as measured by 1/k(fa), T1, and T1sat in the treated group, was smaller compared to that of the untreated group, with significant differences detected between groups at 5, 24, and 48 hours. Our data suggest that a quantitative measure of MT may provide a sensitive and early method to detect the efficacy of therapeutic intervention in experimental stroke.
Insights
Quantitative MRI measures of magnetization transfer (MT) show reduced damage in rats treated with anti-ICAM-1 antibodies after stroke. This method offers early detection of therapeutic efficacy in experimental stroke models.
Area of Science:
- Neuroimaging
- Biomedical Engineering
- Stroke Research
Background:
- Middle cerebral artery occlusion (MCAO) is a common model for experimental stroke.
- Magnetization transfer (MT) MRI provides quantitative measures related to tissue microstructure.
- Assessing therapeutic interventions in stroke requires sensitive and early detection methods.
Purpose of the Study:
- To evaluate the temporal profiles of quantitative magnetization transfer (MT) MRI parameters in an experimental stroke model.
- To assess the efficacy of anti-ICAM-1 monoclonal antibody therapy in reducing ischemic damage using MT parameters.
- To determine if quantitative MT measures can serve as an early indicator of therapeutic intervention effectiveness.
Main Methods:
- 22 male Wistar rats underwent MCAO, with half receiving anti-ICAM-1 antibody treatment.
- Quantitative MT parameters, including the inverse of the apparent forward transfer rate (1/k(fa)), T1sat, and T1, were measured over time.
- The value and area of damage for these MT parameters were analyzed and compared between treated and untreated groups.
Main Results:
- Both treated and untreated groups showed significant increases in 1/k(fa), T1sat, and T1 values and damage areas post-MCAO.
- The increase in MT parameter values and damage areas was significantly smaller in the anti-ICAM-1 treated group compared to the untreated group.
- Significant differences between groups were observed at 5, 24, and 48 hours post-MCAO.
Conclusions:
- Quantitative MT MRI parameters effectively detect changes associated with ischemic damage in experimental stroke.
- Anti-ICAM-1 antibody therapy demonstrated a reduction in MCAO-induced tissue damage as measured by MT parameters.
- Quantitative MT offers a sensitive and early method for evaluating the efficacy of therapeutic interventions in experimental stroke.