TY - JOUR T1 - MR imaging of acute experimental ischemia in cats. JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 7 LP - 11 VL - 7 IS - 1 AU - M Brant-Zawadzki AU - B Pereira AU - P Weinstein AU - S Moore AU - W Kucharczyk AU - I Berry AU - M McNamara AU - N Derugin Y1 - 1986/01/01 UR - http://www.ajnr.org/content/7/1/7.abstract N2 - The evolution of acute cerebral ischemia was documented by magnetic resonance (MR) imaging in 13 mongrel cats with occlusion of the middle cerebral artery through a transorbital approach. The animals were imaged under anesthesia at intervals from 30 min to 10 days after production of the lesion. An MR imager operating at 0.35 T was used with multislice, multi-spin-echo technique (TR = 500-2000 msec; TE = 28, 56 msec). The animals were sacrificed after imaging for pathologic correlation. Infarcts beyond 4 hr of age were visualized in all subjects. The earliest infarct was seen at 30 min (two cats) as an area of high signal intensity on T2-weighted images. In three other cats, however, 3-hr-old infarcts were not detectable. In one animal, a hemorrhage within a 1-week-old area of infarction was not characterized by MR imaging but was identified on CT scanning. The mass effect of the infarction appeared greatest at 2-4 days after infarction. The basal ganglia showed ischemic effects to best advantage. MR imaging offers previously unavailable sensitivity for the early noninvasive detection of cerebral ischemia in vivo. ER -