Association of white matter injury and neuroinflammation in the post-acute phase after ischemic stroke using [18F]FEPPA-PET/MRI
Bibliographic record
Abstract
Cerebral white matter (WM) injury after ischemic stroke is associated with post-stroke cognitive impairment (PSCI), however, the interaction between sustained neuroinflammation and post-stroke WM injury is not well understood. Hybrid PET/MRI can provide insight into pathophysiological mechanisms linking chronic neuroinflammation, ischemic WM injury, and PSCI. Using PET/MRI, this study investigated the relationship between [ 18 F]FEPPA standardized uptake value ratio (SUVr) measurements of glial activation and diffusion tensor imaging (DTI) measurements of microstructure integrity in brain WM regions in the chronic phase at 6-months after acute ischemic stroke. [ 18 F]FEPPA-PET, DTI, and T2-weighted FLAIR were acquired at 6-months post-stroke in 19 elderly humans (seven females; mean age = 76 ± 5 years) with confirmed first-ever acute ischemic stroke using hybrid PET/3T-MRI. Index infarcts, chronic (incidental, covert) infarcts, and WM hyperintensities were manually segmented on FLAIR and excluded from the imaging analysis. Pearson correlation was conducted to assess the association between [ 18 F]FEPPA-SUVr and DTI measurements in WM regions commonly implicated in PSCI. [ 18 F]FEPPA-SUVr was elevated in brain regions ipsilateral to the index infarct at 6-months post-stroke, and these increases correlated with decreases in fractional anisotropy in several WM pathways linked to PSCI, including right superior longitudinal fasciculus (SLF) III ( r = -0.82, p < 0.0001), right anterior thalamic radiation ( r = -0.61, p = 0.006), and right arcuate fasciculus ( r = -0.56, p = 0.01). Elevated [ 18 F]FEPPA-SUVr was also associated with increased mean diffusivity ( r = 0.69, p < 0.001), axial diffusivity ( r = 0.55, p = 0.02), and radial diffusivity ( r = 0.74, p < 0.001) in right SLF III. This study found an association between elevated post-acute glial activation (neuroinflammation) and reduced microstructure integrity in brain WM pathways ipsilateral to ischemic infarcts and remote from WM lesions at 6-months post-stroke. Hybrid PET/MRI is promising to be a valuable tool for probing post-acute neuroinflammation and associated changes in cerebral WM pathways following ischemic stroke.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".