Hyperpolarized 129Xe MRI Captures Elevated Regional Ventilation Heterogeneity in Patients With Bronchiolitis Obliterans Syndrome Following Hematopoietic Stem-cell Transplantation in Children
Notice bibliographique
Résumé
Abstract Rationale: Bronchiolitis Obliterans Syndrome (BOS) is a lung complication of Hematopoietic Stem-Cell Transplantation (HSCT), often with delayed diagnosis as early stages are typically asymptomatic. Once symptoms meet National Institute of Health (NIH) criteria, airway obstruction is typically irreversible. Single-breath Hyperpolarized Xenon MRI (Xe-MRI) detects early pulmonary decline in cystic fibrosis (CF) and was feasible in pediatric HSCT patients. Additionally, it is sensitive to ventilation defects even in asymptomatic post-HSCT subjects with normal FEV1 and those unable to perform spirometry. Xe-MRI can also be done in a multiple-breath washout (MBW) fashion which, while shown to be feasible and repeatable in CF, has not been tested in HSCT or BOS patients. Both methods offer promising non-invasive ways to monitor obstructive changes in lung ventilation due to disease and their regional information on ventilation may be more sensitive to earlier symptoms compared to pulmonary function tests (PFTs). This study aims to evaluate single-breath and MBW Xe-MRI for detecting BOS in pediatric HSCT patients and compare with PFTs and against NIH criteria. Methods: Patients were recruited ≥6 months post-HSCT with institutional approval; some with confirmed BOS per NIH criteria, others with only BOS-like symptoms. Patients performed spirometry (FEV1%) and N2 MBW (lung clearance index, LCI) by ATS/ERS standards. Single-breath Xe-MRI (ventilation defect percent, VDP) and MBW Xe-MRI (fractional ventilation, FV) were performed as previously described. For VDP and FV, their coefficient of variation (CoV, a measure of regional heterogeneity) was calculated using the standard deviation/mean using a 3x3 image kernel. Mann-Whitney U-test assessed group differences. Pearson's correlation coefficient was used to correlate MRI with PFTs. Results: 11 children [mean age 12±3 years, 5 BOS, 6 non-BOS] were recruited. Xe-MRI was well-tolerated by all participants with no adverse events. Significant differences between BOS/non-BOS were observed by both measures of regional ventilation heterogeneity, CoVVDP (P=0.017) and CoVFV (P=0.016), but not by either measure of regional ventilation, VDP or FV (Figure 1). Both PFTs (FEV1%, LCI) were also able to distinguish between groups, as expected. CoVVDP correlated significantly with LCI (R=0.74, P=0.014) and FEV1% (R=-0.65, P=0.030). No other significant correlations between Xe-MRI and PFTs were observed. Conclusion: Measures of regional ventilation heterogeneity (CoVVDP and CoVFV) can distinguish BOS and non-BOS, while VDP, FV cannot. Changes in ventilation heterogeneity (either spatial, as reflected by imaging, or temporal, as reflected by LCI) may be an important marker for detecting BOS. Absolute advantage of MRI over PFTs requires further study.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| 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) | 0,001 | 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 source (Gemma direct ou Codex distillé), 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 ».