th  - 1988 - 51st ENC Conference

. °- F
64 I
MICROSCOPIC IMAGING OF LIVE MOUSE AT 400 MHz
Susanta K. Sarkar*, Russell Greig and Mark Mattingly'
Smith K1ine & French Laboratories, King of Prussia, PA 19406-0939, and
'Bruker Instruments, Billerica, MA, 01821
The development of NMR microscopy is potentially useful in determining
the fine structure of pathological lesions, and in particular in monitoring
the growth and spread of malignant tumors in small animals. However, since
the signal to noise ratio is the key limitation for imaging experiments with
microscopic resolution, it is necessary to do these experiments at higher
field strength.
He demonstrate here the feasibility of obtaining live mouse images with a
resolution of lOOxlOOx650 I~m at 400 MHz. Examples wtll tnclude images of
human tumor xenografts tn nude mtce and mouse kidney. A wide bore Bruker 400
MHz NMR spectrometer, modified for imaging experiments, was used for these
experiments.
65 I
APPLICATION OF A ONE DIMENSIONAL IMAGING EXPERIMENT=
Babul Borah, Norwich Eaton Pharmaceuticals, Inc., Norwich, NY 13815 and
Nikolaus M. Szeverenyi, SUNY Health Science Center, Syracuse, NY 13210
Although the trend has been towards increasing complexity in imaging experiments,
we have found a useful application for a one dimensional imaging experiment in quan-
tifying and characterizing the fluid changes in the rat leg as a result of arthritis.
A large rf probe is used to insure that BI is uniform in the region of the rat
leg and a single linear magnetic field gradient is applied continuously in the di-
rection of the leg. A spin echo pulse sequence provides a signal which maps the
spatial distribution of water and fat along the leg. In order to make quantitative
measurements on the leg, a reference capsule containing water is placed Just beyond
the paw. TI and T2 measurements can be obtained using the same techniques as in
spectroscopy and suggest that there are two fluid components which are sensitive to
infl-,,,atory soft tissue changes. One component has a T2 of 34 ms and the other 120
ms. These components increase in concentration by a factor of 3 and 7 respectively
as the lesion of the Joint progresses and appear to peak in 15-20 days after the
induction of the arthritis in the rat.
131