Abstract
Following chronic denervation, MRI evaluation of fast rabbit muscles revealed a distinct increase of signal intensity and T2 relaxation time. These changes were missing or less pronounced after treatment with a new type of electrical stimulation, which previously had proved effective in avoiding muscle atrophy. One month after denervation, there was a slight increase of signal intensity as well in the stimulated as in the untreated animals, after two months, however, the increase was statistically significant only in the non-stimulated muscles. T2 relaxation time showed a slight increase after one month of therapy, while there was a significant increase after one and two months without therapy. After 36 months of electrical stimulation, there was no increase of T2 at all. The results indicate 1), that MRI can be used when monitoring stimulation effects on denervated muscle, and 2), that, for this purpose, T2 relaxation time is more useful than signal intensity.
Subject
Literature and Literary Theory,History,Cultural Studies
Reference32 articles.
1. Dooms G.C., Fisher M.H., Hricak H., Higgins C.B MR imaging of intramuscular hemorrhage // J. Comput. Assist. Tomogr.—1985.—Vol.9.—P.908—913.
2. Ehmann R.L. Interpretation of magnetic resonance images // Magnetic Resonance of the Musculoskeletal System /T.H.Berquist, R.L.Ehmann, M.L.Richardson (eds.).—New York: Raven, 1987.—P.23—64.
3. Eichhorn K.F., Schubert W., David E. Maintenance, training and functional use of denervated muscles // J. Biomed. Eng.—1984.—Vol.6.—P.205—211.
4. Fleckenstein J.L., Canby R.C., Parkey R.W., Peshock R.M. Acute effects of exercise on MR imaging of skeletal muscle in normal volunteers // Am. J. Radiol.—1988.—Vol. 151.— P.231—237.
5. Fullerton G.D., Cameron 1.1. Relaxation of biological tissues // Biomedical Magnetic Resonance Imaging /F.W.Wehrli, D.Shaw, J.B.Kneeland (eds.).—VCII, Weinheim, 1988.— P. 115—155.