OPTIMIZING TECHNICAL CONDITIONS FOR MAGNETIC-RESONANCE-IMAGING OF THERAT-BRAIN AND ABDOMEN IN A LOW MAGNETIC-FIELD

The present study was designed to establish the appropriate technical conditions for magnetic resonance imaging (MRI) of the head and abdome n in rats using a low magnetic field strength (0.2 T) MRI unit equippe d with three radio frequency (RF) coils: a custom-made solenoid coil, a temporomandibular joint surface coil and a knee quadrature (QD) RF c oil, Male adult Sprague-Dawley rats were used, T1 and T2 relaxation ti mes of both anatomic regions were measured from T1 and T2 maps, An app ropriate parameter was then used to make final T1 and T2 weighted imag es, It was found that the most suitable coil for the head was the cust om-made solenoid coil, and that for the abdomen, the knee QD coil, The T1 and T2 relaxation times were 314 to 316 msec and 72 to 74 msec for the head, and 220 to 252 msec and 42 to 51 msec for the abdomen. The optimum parameters for the head were TR/TE = 400/38 msec in T1 weighte d images and TR/TE = 1,800/110 msec in T2 weighted images, and for the abdomen, TRITE = 300/25 msec in T1 weighted images and TR/TE = 1,500/ 110 msec in T2 weighted images, These results demonstrate that a low m agnetic field strength MRI unit has potential for MRI study of the bra in and abdomen in rats.