Biomedical subjects
Publications and source records attributed to I Mano.
This paper presents our ongoing project in which normal human anatomy and its quantitative data are systematically arranged in a computer. The final product, the Computerized Three-Dimensional Normal Atlas, will be able to supply tomographic images in any direction, 3-D images, and coded information on organs, e.g., anatomical names, CT numbers, and T1 and T2 values.
MRI of twenty patients with cerebral infarction were reported with their X-CT. MRI with long SE mode clearly showed the ischemic lesion at 18 hours after insult, whereas X-CT performed immediately after MRI scanning showed no abnormality. The signal contrast of the lesion with long SE mode seemed to increase slightly during the patient's course, for a period of several months. The MRI images with long SE at the chronic stage were varied: small lesions appeared as hot areas, whereas large lesions appeared as cold areas and were accompanied with signal enhancement in the surrounding areas. A phantom study was also performed and it was determined that MRI was superior to X-CT in its ability to detect tissue water. One of the reasons for the high diagnostic capability of MRI for acute stroke was, therefore, attributed to this experimental result.
Nuclear magnetic resonance (NMR) imaging was used to evaluate the intracerebral changes over time in gerbils after unilateral carotid artery ligation. Each animal was imaged during one of three stated periods 3-28 hr after surgery and again after administration of dexamethasone, morphine, or naloxone, agents reported to affect the clinical outcome of ischemic cerebral lesions. Asymptomatic animals exhibited no differences between the occluded and control hemispheres in relative signal intensity or in T1 or T2 relaxation times, but symptomatic animals demonstrated significant differences in these parameters between hemispheres. The ischemic lesion was detected at the earliest imaging time, 3 hr after surgery. A linear increase was observed in the relative interhemispheric signal intensity in three of four intensity images and in T1 and T2 relaxation times over the 24 hr experiment. No effect was noted on any image parameter as a result of pharmacologic manipulations. The results suggest that NMR may be of significant diagnostic importance for acute cerebral ischemia and infarction in man.