Titre
Non-invasive monitoring of renal oxygenation using BOLD-MRI: a reproducibility study
Type
article
Institution
UNIL/CHUV/Unisanté + institutions partenaires
Périodique
Auteur(s)
Simon-Zoula, S. C.
Auteure/Auteur
Hofmann, L.
Auteure/Auteur
Giger, A.
Auteure/Auteur
Vogt, B.
Auteure/Auteur
Vock, P.
Auteure/Auteur
Frey, F. J.
Auteure/Auteur
Boesch, C.
Auteure/Auteur
Liens vers les personnes
Liens vers les unités
ISSN
0952-3480
Statut éditorial
Publié
Date de publication
2006-02
Volume
19
Numéro
1
Première page
84
Dernière page/numéro d’article
9
Notes
Clinical Trial
Journal Article --- Old month value: Feb
Journal Article --- Old month value: Feb
Résumé
Blood oxygenation level-dependent (BOLD) MRI was shown to allow non-invasive observation of renal oxygenation in humans. However, clinical applications of this type of functional MRI of the kidney are still limited, most likely because of difficulties in obtaining reproducible and reliable information. The aim of this study was to evaluate the reproducibility and robustness of a BOLD method applied to the kidneys and to identify systematic physiological changes potentially influencing the renal oxygenation of healthy volunteers. To measure the BOLD effect, a modified multi-echo data image combination (MEDIC) sequence was used to acquire 12 T2*-weighted images within a single breath-hold. Three identical measurements were performed on three axial and three coronal slices of right and left kidneys in 18 volunteers. The mean R2* (1/T2*) values determined in medulla and cortex showed no significant differences over three repetitions and low intra-subject coefficients of variation (CV) (3 and 4% in medulla and cortex, respectively). The average R2* values were higher in the medulla (16.15 +/- 0.11) than in the cortex (11.69 +/- 0.18) (P < 0.001). Only a minor influence of slice orientation was observed. Mean R2* values were slightly higher (3%) in the left than in the right kidney (P < 0.001). Differences between volunteers were identified (P < 0.001). Part of these differences was attributable to age-dependent R2* values, since these values increased with age when medulla (P < 0.001, r = 0.67) or cortex (P < 0.020, r = 0.42) were considered. Thus, BOLD measurements in the kidney are highly reproducible and robust. The results allow one to identify the known cortico-medullary gradient of oxygenation evidenced by the gradient of R2* values and suggest that medulla is more hypoxic in older than younger individuals. BOLD-MRI is therefore a useful tool to study sequentially and non-invasively regional oxygenation of human kidneys.
Sujets
PID Serval
serval:BIB_E8C5C341F390
PMID
Date de création
2008-01-25T12:03:07.713Z
Date de création dans IRIS
2025-05-20T22:55:41Z