CT angiography

Wildermuth S, Knauth M, Brandt T, Winter R, Sartor K, Hacke W. Role of CT angiography in patient selection for thrombolytic therapy in acute hemispheric stroke. Stroke 1998 29 935-938 [see comment]. 

FIGURE 6.1 CT angiography of an EC-IC bypass, showing the new intracranial course of the right superficial temporal artery, anastamosed to the middle cerebral artery M2 segment. 

Knauth M, von Kummer R, Jansen O, Hahnel S, Dorfler A, Sartor K. Potential of CT angiography in acute ischemic stroke. Am J of Neurorad 1997 18 1001-10. 

Shrier D, Tanaka H, Numaguchi Y, Konno S, Patel U, Shibata D. CT angiography in the evaluation of acute stroke. Am J Neuroradiol 1997 18 1011-1020. 

Peak tissue enhancement is determined by blood volume but also depends upon cardiac output (which can vary from one patient to the other) and the volume of CA injected [10]. Furthermore, in the case of all presently available NS-CA, the intra- and extra-vascular components of enhancement cannot be evaluated separately [ 14]. It is also well known that the imaging window in CT angiography is very short and is classically compensated by the injection of high doses of NS-CA or the use of bolus-tracking software. 

Quality standards for diagnosis of stenosis are set by catheter DSA, and noninvasive methods have to be compared with these. In the majority of cerebrovascular diseases, however, invasive methods are no longer indicated and are replaced by MRA or CT angiography, respectively. To assure an optimal therapy of stroke, vascular imaging has to provide answers to a number of clinical questions ... 

Correlation of carotid stenosis diameter and cross-sectional areas with CT angiography. American Journal of Neuroradiology 27 638-642... 

Hypoattenuated areas on CT represent an increase in the net water content of the involved brain parenchyma. Lowering of CT attenuation allows for quantification and localization of edema, which is the result of net change in water content of the area of interest. This increase in water content could be readily related to the vasogenic edema. Based on this physics, different CT techniques have been developed to monitor edema (1) noncontrast-enhanced CT (NECT), (2) perfusion CT (PCT), and (3) CT angiography (CTA). 

Esteban JM, Alonso A, Cervera V, Martinez V. One-molar gadolinium chelate (gadobutrol) as a contrast agent for CT angiography of the thoracic and abdominal aorta. Eur. Radiol. 2007 17 2394-2400. 

Furuse, J., Maru, Y., Yoshino, M., Mera, K., Suml, H., Seklgnchl, R., Sataka, M., Hasebe, T., Ochlal, A. Assessment of arterial tumor vascularity in small hepatocellular carcinoma. Comparison between color Doppler ultrasonography and radiographic imagings with contrast medium dynamic CT, angiography, and CT hepatic arteriography. Eur. J. Radiol. 2000 36 20-27... 

Willmann, J.K., Weishaupt, D., Bdhm, T., Pfammatter, T., Seifert, B., Marincek, B., Bauerfeind, R Detection of submucosal gastric fundal varices with multi-detector row CT angiography. Gut 2003 52 886-892... 

The study of cerebrovascular disease has advanced markedly in recent years with advances in non-invasive imaging methods such as MR angiography and CT angiography as well as an improved understanding of the immune system in the pathogenesis of atherosclerosis. Atherosclerotic cerebrovascular disease is a common cause of strokes and shows a predilection for sites such as the bifurcation of the common carotid artery into the internal and external carotid arteries and the aortic arch and the major intracranial arteries such as the basilar artery and the middle cerebral arteries. Occlusive atherosclerotic vascular disease of these large extracranial arteries is responsible for as many as 20-30% of ischemic strokes and intracranial steno-occlusive disease causes around 5-10% of ischemic strokes. 

---