title: Longitudinal and noninvasive assessment of emphysema evolution in a murine model using proton MRI.
abstract: Ultrashort echo time (550 μs) MR imaging was implemented to track the emphysema development in mice lung challenged with elastase. Two parameters, namely, signal intensity and T 2, were used to monitor the disease evolution. Nine mice were imaged before and at 24 h as well as at 3 and 8 weeks after elastase instillation. Five mice instilled with saline served as controls. At week 8, the mean normalized signal intensity ± SD was 0.89 ± 0.20 for healthy controls and 0.64 ± 0.10 for animals with emphysema. Similarly, a reduced value of T 2 (1.27 ± 0.35 ms vs 0.96 ± 0.18 ms) was found in the emphysema group. The mean signal intensity drop and the reduction of T 2 were prominent at 3 weeks following elastase instillation and stabilized between 3 and 8 weeks. The results indicated an excellent agreement between MR findings and histological morphometry (signal intensity, r = -0.78, P = 0.004; T 2, r = -0.78, P = 0.001). This result shows that proton MRI allows structural changes at alveolar level to be monitored longitudinally. This technique, applied routinely in preclinical trials will represent a valuable tool for assessment of drug therapy efficacy.
authors.affiliation: Université de Lyon, CREATIS-LRMN, Lyon, France.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zurek
authors.forename: Laurent
authors.initials: L
authors.lastname: Boyer
authors.forename: Philippe
authors.initials: P
authors.lastname: Caramelle
authors.forename: Jorge
authors.initials: J
authors.lastname: Boczkowski
authors.forename: Yannick
authors.initials: Y
authors.lastname: Crémillieux
mesh_terms: D000465:Algorithms; D000818:Animals; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010363:Pattern Recognition, Automated / Q000379:methods*; D011522:Protons; D011656:Pulmonary Emphysema / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
chemical_list: D011522:Protons