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J R Fike

Publications and source records attributed to J R Fike.

56 records · Page 4Linked to original sources
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Relative uptake of low- and high-osmolality contrast media in CT of brain tumors.

The magnitude and time course of contrast enhancement in spontaneous canine brain tumors was determined for two contrast agents: meglumine iothalamate and sodium meglumine ioxaglate. Tumor enhancement during contrast infusion and at 5, 10, 15, 30, and 45 min was measured using quantitative computed tomography. Blood iodine was measured using x-ray fluorescence. Peak contrast enhancement occurred during the infusion, and the magnitude was the same for both agents. Per gram of iodine infused, blood iodine was 12.4% higher with ioxaglate than iothalamate. The monoionic dimer ioxaglate is as effective as iothalamate for enhancement of canine brain tumors.

Animals↗
PubMedDate not supplied

Comparison of xenon-enhanced CT with ultrafast CT for measurement of regional cerebral blood flow.

PURPOSE: To compare an ultrafast CT method for estimating regional cerebral blood flow with a more commonly used xenon-enhanced CT method. METHODS: Xenon CT and ultrafast CT were used to estimate regional cerebral blood flow (rCBF) in 12 healthy beagle dogs. Measurements were obtained for left and right hemisphere, cortical gray matter, basal ganglia, and deep white matter. The ability of each method to show differences in blood flow between regions of high flow (gray matter) and low flow (white matter) was evaluated, both for large (> 0.75 cm3) and small (< 0.5 cm3) regions of interest. In addition, side-to-side differences in rCBF were evaluated to determine the minimum difference that would suggest a significant alteration in blood flow. RESULTS: There was less interanimal variance in absolute rCBF measurements obtained using xenon CT; ultrafast CT appeared to accentuate rCBF differences between high flow and low flow regions. There were strong side-to-side correlations in rCBF when measured by ultrafast CT, which suggests that this technique may be particularly useful in detecting focal alterations in rCBF restricted to one hemisphere of the brain. CONCLUSIONS: Ultrafast CT measures of rCBF compare favorably with those obtained using xenon CT.

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