European radiology
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An uncommon cause of cerebral ischemia in the territory of the posterior cerebral artery (PCA) is the combination of a fetal origin of the PCA and atherosclerotic disease in the internal carotid artery. This study compared the accuracy of CTA with DSA in the assessment of a fetal origin of the PCA. Patients in whom an intracranial DSA and CTA had been performed were reviewed. ⋯ Sensitivity and specificity of CTA in the assessment of a fetal origin could be estimated at 100 and 97%, respectively. Positive and negative predictive values were 77 and 100%, respectively. CTA can be considered a valid diagnostic tool for the assessment of a fetal origin of the PCA in patients with a cerebral ischemic event in the territory of the PCA.
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The objective of this study was to develop a technique which would permit access to the entire contents of long bones using a minimally invasive approach. Vascular catheterization techniques were used to allow access to the entire marrow cavity through a minimal percutaneous approach. A new device was also developed to reach the epiphysis of the long bone. ⋯ A percutaneous approach was made through the bone shaft from a remote entry site using principles from endoscopy in an ex vivo experiment. This method may become an alternative technique when a direct approach to lesional sites in long bones is dangerous or impossible. For example, it could be used in cases of preventive cement injections in weakened bones.
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We assessed the feasibility of MR digital subtraction angiography (DSA) using parallel imaging and keyhole data sampling in the diagnosis of cerebrovascular diseases (CVDs) in 11 patients. Their diseases included arterial trunk stenosis/occlusion ( n=4), aneurysm ( n=3), arteriovenous malformation ( n=2), venous angioma ( n=1), and sinus thrombosis ( n=1). ⋯ When compared with conventional angiograms ( n=7), details were missed in four patients (incomplete demonstration of aneurysmal neck in two and poor separation of AVM components in two). Although inferior to conventional angiography, this technique can provide both anatomical and hemodynamic information of CVDs.
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Renal vasoconstriction with resultant tissue hypoxia, especially in the renal medulla, has been suggested to play a role in contrast media (CM)-induced nephropathy. In this study we investigated the effects of injection of the non-ionic low-osmolar CM iopromide with and without pretreatment with the selective adenosine A1-receptor antagonist DPCPX. The effects were evaluated on regional renal blood flow, outer medullary oxygen tension (PO2) and urine output in normal anaesthetised rats. ⋯ Urine output increased 28-fold by CM while arterial blood pressure was reduced. The CM-mediated effect on haemodynamics, PO2, urine output and blood pressure was unaffected by the A1-receptor antagonist. Adenosine A1-receptors are not important mediators of the depression of outer medullary blood flow and PO2 caused by the CM iopromide in the normal rat; however, A1-receptors are tonically active to regulate renal haemodynamics, PO2 and urine production during normal physiological conditions.