Multiexponential T2 analyses in a murine model of hepatic fibrosis at 11.7 T MRI. (7th June 2012)

• Record Type: Journal Article
• Authors: Scalera, Jonathan E.; Soto, Jorge A.; Jara, Hernan; Ozonoff, Al; O'Brien, Michael; Anderson, Stephan W.
• Is Part Of: NMR in biomedicine. Volume 26:Number 1(2013:Jan.)
• Page Start: 83
• Page End: 90
• Publication Date: 2012-06-07
• Subjects: Nuclear magnetic resonance -- Periodicals; Magnetic Resonance Spectroscopy -- Periodicals; 574
• DOI: 10.1002/nbm.2822
• Languages: English
• ISSNs: 0952-3480

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>This study evaluated the effects of hepatic fibrosis on the multiexponential <italic>T</italic><sub>2</sub> (MET<sub>2</sub>) relaxation of <italic>ex vivo</italic> murine liver specimens using an 11.7 T MRI. This animal study was approved by the Institutional Animal Care and Use Committee. Eighteen male C57BL/6 mice were divided into control (<italic>n</italic> = 3) and experimental (<italic>n</italic> = 15) groups; the latter group was fed a 3, 5‐dicarbethoxy‐1, 4‐dihydrocollidine‐supplemented diet to induce hepatic fibrosis. <italic>Ex vivo</italic> liver specimens were imaged using an 11.7 T MRI scanner. A multi‐echo spin‐echo sequence was utilized for subsequent MET<sub>2</sub> analysis. Degrees of fibrosis were determined by a pathologist, as well as by digital image analysis. Scatterplot graphs comparing various features of the MET<sub>2</sub> signal decay with the degrees of fibrosis were generated, and correlation coefficients were calculated. Two distinct peaks of the MET<sub>2</sub> signal decay were identified in all liver specimens: a short <italic>T</italic><sub>2</sub> component with a geometric mean <italic>T</italic><sub>2</sub> (GMT<sub>2</sub>) approximating 30 ms; and a long <italic>T</italic><sub>2</sub> component with GMT<sub>2</sub> approximating 400 ms. Strong correlation was found between the degree of hepatic fibrosis and the amplitude of the short <italic>T</italic><sub>2</sub> component, with a higher degrees of fibrosis associated with a lower amplitude. Moderate correlation was also found between hepatic fibrosis and the GMT<sub>2</sub> values of the long <italic>T</italic><sub>2</sub> component, with higher degrees of fibrosis associated with lower GMT<sub>2</sub> values. The study of hepatic microenvironments using MET<sub>2</sub> analyses offers potential utility in the ongoing development of the noninvasive assessment of hepatic fibrosis using MRI. Copyright © 2012 John Wiley & Sons, Ltd.</p> </abstract>