FUNCTIONAL PET/MRI OF KNEE SYNOVIAL MACROPHAGE ACTIVITY BEFORE AND AFTER TOTAL KNEE ARTHROPLASTY
Notice bibliographique
Résumé
Total knee arthroplasty (TKA) is a surgery with high success rates and good patient outcomes. However, 6.9% of knee replacement surgeries are revisions of old implants due to ongoing pain, stiffness, and loosening. Revision TKA is more expensive and has worse patient outcomes. Recent studies have begun to explore the role of the inflammatory response in poor TKA outcomes. Inflammation is an important predictor of pain in osteoarthritis (OA) and synovial inflammation may play a role in knee stiffness after TKA. Macrophages are the dominant immune cells of the synovium and regulate knee inflammation, and when activated, they upregulate mitochondrial translocator protein (TSPO) expression. Current standard of care features Magnetic Resonance Imaging (MRI) to assess structural changes in the joint. Positron Emission Tomography (PET) can be used to image important biological processes at the cellular level. [18F]FEPPA is a PET tracer that targets TSPO with high specificity. The goal of this work was to validate the use of [18F]FEPPA PET/MRI in the assessment of macrophage activation in knee synovial tissue. This method may allow non-invasive imaging of important inflammatory processes and understand the role of activated macrophages in ongoing pain, stiffness, and loosening after TKA . To validate the use of [18F]FEPPA in imaging activated macrophages in vivo, synovial tissue was gathered from 12 participants with end stage OA who underwent primary TKA. Knee synovial tissue was sectioned and embedded on slides. Tissue sections were incubated in [18F]FEPPA and imaged by autoradiography for 6 hours. Adjacent tissue sections were incubated with DAPI, CD68 antibody, and TSPO antibody for immunofluorescent analysis of the actual macrophage activation. 6 of the full cohort were imaged in a 3T hybrid PET/MRI after injection with [18F]FEPPA and a 45-minute uptake period. MR of both knee joints was performed with sequences including 3D Dual Echo Steady State (DESS), Bilateral T1 weighted and Fast Spin Echo (FSE) with metal artifact reduction if contralateral TKA was present. Standardized Uptake Values (SUV) were calculated from the measured PET signal, injected dose, and patient mass. [18F]FEPPA tracer uptake calculated from autoradiography correlated to the true macrophage activation measured through TSPO+ immunofluorescence with r = 0.85 and p = 0.0029. SUV calculated from PET/MRI was correlated to true macrophage activation found through immunofluorescence with r = 0.90 and p = 0.083. Attenuation correction maps corrected for metal artefacts enabled visualization and measurement of tracer uptake surrounding the femoral and tibial components. Understanding the role of knee joint inflammation may be important in managing pain and stiffness after TKA. The underlying cause of poor TKA outcomes are often unclear.[18F]FEPPA PET/MRI uptake in knee synovial tissue was validated to correlate to the true macrophage activity. This tool may be able to diagnosis a cellular response as the cause of pain or dissatisfaction after TKA. Future work using [18F]FEPPA PET/MRI could assess different reaction types to metal or plastic implant debris, joint stiffness and fibrosis, and periprosthetic infection.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».