Extent of Microstructural Tissue Damage Correlates with Hemodynamic Failure in High-Grade Carotid Occlusive Disease:
A Seiler1, R Deichmann2, U Nöth2
1From the Department of Neurology (A.S., W.P., O.C.S.) Alexander.Seiler@kgu.de.
Background And Purpose:
Chronic hemodynamic impairment in high-grade carotid occlusive disease is thought to cause microstructural abnormalities that might be subclinical or lead to subtle symptoms including cognitive impairment. Quantitative MR imaging allows assessing pathologic structural changes beyond macroscopically visible tissue damage. In this study, high-resolution quantitative T2 mapping combined with DSC-based PWI was used to investigate quantitative T2 changes as a potential marker of microstructural damage in relation to hemodynamic impairment in patients with unilateral high-grade carotid occlusive disease.
Materials And Methods:
Eighteen patients with unilateral high-grade ICA or MCA stenosis/occlusion were included in the study. T2 values and deconvolved perfusion parameters, including relative CBF, relative CBV, and the relative CBF/relative CBV ratio as a potential indicator of local cerebral perfusion pressure, were determined within areas with delayed TTP and compared with values from contralateral unaffected areas after segmentation of normal-appearing hypoperfused WM and cortical regions. Hemispheric asymmetry indices were calculated for all parameters.
Results:
Quantitative T2 was significantly prolonged (P < .01) in hypoperfused tissue and correlated significantly (P < .01) with TTP delay and relative CBF/relative CBV reduction in WM. Significant correlations (P < .001) between TTP delay and the relative CBF/relative CBV ratio were found both in WM and in cortical areas.
Conclusions:
Quantitative T2 can be used as a marker of microstructural tissue damage even in normal-appearing GM and WM within a vascular territory affected by high-grade carotid occlusive disease. Furthermore, the extent of damage correlates with the degree of hemodynamic failure measured by DSC perfusion parameters.
Insights
Quantitative T2 mapping detects microstructural damage in normal-appearing brain tissue affected by carotid occlusive disease. This damage correlates with hemodynamic impairment, offering a new marker for assessing disease severity.
Area of Science:
- Neuroimaging
- Cerebrovascular Disease
- Quantitative MRI
Background:
- High-grade carotid occlusive disease can cause chronic hemodynamic impairment.
- This impairment may lead to subclinical microstructural brain abnormalities and cognitive issues.
- Quantitative MRI offers a way to detect these subtle pathological changes.
Purpose of the Study:
- To investigate quantitative T2 changes as a marker of microstructural damage.
- To assess the relationship between T2 changes and hemodynamic impairment in carotid occlusive disease.
- To utilize high-resolution T2 mapping and DSC-PWI for quantitative analysis.
Main Methods:
- Eighteen patients with unilateral high-grade carotid stenosis/occlusion were studied.
- Quantitative T2 values and DSC perfusion parameters (rCBF, rCBV, rCBF/rCBV ratio) were measured.
- Comparisons were made between affected and contralateral unaffected brain regions.
Main Results:
- Quantitative T2 was significantly prolonged in hypoperfused white matter (WM).
- Prolonged T2 correlated with delayed TTP and reduced rCBF/rCBV in WM.
- Significant correlations were found between TTP delay and rCBF/rCBV ratio in WM and cortical areas.
Conclusions:
- Quantitative T2 serves as a marker for microstructural damage in normal-appearing brain tissue.
- This damage is present even in areas affected by high-grade carotid occlusive disease.
- The extent of damage correlates with the degree of hemodynamic failure indicated by DSC perfusion parameters.
More Related Videos
05:56Author Spotlight: Enhancing Diagnostic Strategies and Biomarker Development for Comprehensive Lung Function Analysis
Published on: August 9, 2024
12:15Optimized System for Cerebral Perfusion Monitoring in the Rat Stroke Model of Intraluminal Middle Cerebral Artery Occlusion
Published on: February 17, 2013
Related Concept Videos
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
02:20Correlations
01:14Imaging Studies I: CT and MRI
Description of the Procedures
Computed Tomography (CT) scan:
Computed Tomography (CT) scans use X-ray technology to generate detailed images of bones, organs, and tissues. During the scan, the patient lies on a moving table...
01:27Correlation and Causation
Correlation versus Causation
If the dependent variable increases or decreases when the independent variable increases, there is a positive or negative...
01:19Graded Potential
Graded potentials fall into two categories: depolarizing and hyperpolarizing. Depolarizing graded potentials typically occur when sodium (Na+) or...
01:09Correlation
Two variables, for example, a and b, are said to be positively correlated if both variables move in the same direction. In other words, a positive correlation exists between two variables, a and b, if: