AJNR. American journal of neuroradiology
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AJNR Am J Neuroradiol · May 1994
Stroke risk after abrupt internal carotid artery sacrifice: accuracy of preoperative assessment with balloon test occlusion and stable xenon-enhanced CT.
To evaluate stable xenon-enhanced CT cerebral blood flow with balloon test occlusion as a predictor of stroke risk in internal carotid artery sacrifice. ⋯ Our protocol provided a statistically significant reduction in subsequent infarction rate and infarction-related death rate when compared with a control group of normotensive abrupt internal carotid artery occlusion patients who did not undergo any preoperative stroke-risk assessment (reported in the literature). The estimated false-negative rate for our preoperative assessment protocol ranged from 3.3% to 10% depending on the assessment of the cause of the three potentially flow-related infarctions. Although life-threatening major vascular territory infarctions have been avoided, our protocol is less sensitive to changes predicting smaller, often minimally symptomatic, vascular border zone infarctions and does not predict postoperative thromboembolic strokes.
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AJNR Am J Neuroradiol · May 1994
MR imaging and MR angiography in the evaluation of pulsatile tinnitus.
1) To evaluate the scope of imaging findings seen with spin-echo MR and MR angiography (MRA) in patients with pulsatile tinnitus; 2) to determine whether MRA adds additional imaging information (to that provided by spin-echo MR) necessary for determining the cause of pulsatile tinnitus; and 3) to suggest MR and MRA imaging techniques for evaluation of patients with pulsatile tinnitus. ⋯ MRA, in conjunction with spin-echo imaging, markedly enhances the ability of MR to diagnose the lesions responsible for pulsatile tinnitus.
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In order to obtain high resolution images of fixed excised rat spinal cords we have developed a technique using a 6-mm bore, two-turn saddle coil, with a usable imaging length of approximately 4 cm. MR imaging is performed on a prototype 31-cm bore, 1.9-T system with a 1.5-mm section thickness and 7.6-mm field of view.