Serial magnetic resonance imaging of evolving focal cerebral ischemia in the CAT

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6638346

Barnett, G H; Lorig, R J; Jones, S C; Friel, H T; Modic, M T; Little, J R

Magnetic resonance imaging (MRI) is recognized as a sensitive medium for detecting lesions within the central nervous system. Three cats were scanned under light pentobarbital anesthesia using various MRI techniques before and after right middle cerebral artery (MCA) occlusion. Scanning began as early as four minutes after MCA occlusion and continued 8 to 10 hours. The animals were subsequently perfused with a colloidal carbon and phosphate buffered formalin. Brains were removed and sliced for histopathologic examination. The sharpest images were produced with a single spin-echo, multi-slice technique using a 0.6 Tesla (T) FIELD, 0.4 cm slice thickness, and a surface coil. Changes were apparent within 1 hr after MCA occlusion with T2 weighting (TR 2000 msec, TE 120 msec). Increased signal with this technique correlated with areas of decreased colloidal carbon perfusion. One animal with a large cortical infarction showed increased cortical signal at the time of the first MRI scan completed in the first 20 min. An animal with only mild cortical changes and severe ischemic changes in the dorsal thalamus nuclei had similar MRI results. T1 weighted images (TR 500 msec, TE 30 msec) revealed changes in hemispheric contour possibly corresponding to edema at 4 hours post occlusion. One animal imaged with almost double the slice thickness (0.75 cm) and with a 1.5 T field showed poor image quality using the above techniques but without a surface coil. MRI is sensitive in detecting changes due to cerebral ischemia within 30 minutes of onset. Increased MRI signal correlated with areas of decreased colloidal carbon perfusion, demonstrated at later times.

• Research Organization: Cleveland Clinic Foundation, Cleveland, OH
• OSTI ID: 6638346
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550602* -- Medicine-- External Radiation in Diagnostics-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
ALDEHYDES
ANIMALS
ARTERIES
BLOOD VESSELS
BODY
BRAIN
BUFFERS
CARBON COMPOUNDS
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CATS
CENTRAL NERVOUS SYSTEM
CEREBRAL CORTEX
CEREBRUM
COLLOIDS
DETECTION
DIAGNOSIS
DIAGNOSTIC TECHNIQUES
DIAGNOSTIC USES
DISEASES
DISPERSIONS
EDEMA
FORMALDEHYDE
HISTOLOGY
IMAGE PROCESSING
IMAGES
INFUSION
INTAKE
ISCHEMIA
MAMMALS
NERVOUS SYSTEM
NMR IMAGING
ORGANIC COMPOUNDS
ORGANS
OXYGEN COMPOUNDS
PATHOLOGICAL CHANGES
PHOSPHATES
PHOSPHORUS COMPOUNDS
PROCESSING
SENSITIVITY
SYMPTOMS
USES
VASCULAR DISEASES
VERTEBRATES