Angiography Conventional

Pan XM, Saloner D, Reilly LM, Bowersox JC, Murray SP, Anderson CM, Gooding GA, Rapp JH. Assessment of carotid artery stenosis by ultrasonography, conventional angiography, and magnetic resonance angiography correlation with ex vivo measurement of plaque stenosis. J Vase Surg 1995 21(l) 82-88 [discussion 88-89]. 

Contrast-enhanced magnetic resonance angiography (MRA) could be an interesting alternative to conventional X-ray angiography, for both safety and financial considerations [3]. 

This patient is undergoing cerebral angiography. Digital x rays use electronic signals to form visual images, rather than the photographic method of the conventional x ray. 

Remonda L, Senn P, Barth A et al. (2002) Contrast-enhanced 3D MR angiography of the carotid artery comparison with conventional digital subtraction angiography. AJNR Am J Neuroradiol 23 213-219... 

External validity can also be affected if trials have protocols that differ from usual clinical practice. For example, prior to randomization in the trials of endarterectomy for symptomatic carotid stenosis patients had to be diagnosed by a neurologist and to have conventional arterial angiography, neither of which are routine in many centers. The trial intervention itself may also differ from that used in current practice, such as in the formulation and bioavailability of a drug, or the type of anesthetic used for an operation. The same can be true of the treatment in the control group in a trial, which may use a particularly low dose of the comparator drug or fall short of best current practice in some... 

Norris J, Rothwell PM (2001). Noninvasive carotid imaging to select patients for endarterectomy Is it really safer than conventional angiography Neurology 56 990-991... 

The hepatic vessels may be visualised by conventional angiography or venography. These are invasive techniques requiring the injection of contrast media into the artery or vein via catheters during radiographic screening. Stenoses or occlusions are identified, e.g. occlusion of the hepatic veins in Budd-Chiari syndrome. 

Conventional fluorescein angiography has been a very useful clinical tool to assess the ocular vasculature. However, it has a number of limitations. First, the dye rapidly fills both the retinal and choroidal vessels thus, the visualization of small vascular beds, such as CNV, is often obscured by the lack of contrast caused by the bright fluorescence emanating from the large volume of dye present in the... 

Figure 4 Fluorescein angiography and LTA of an occult CNV in a rat model. The conventional fluorescein angiograms, obtained at (A) 29 sec and (B) 3.5min after injection, reveal the presence of a patchy fluorescent area that does not evolve over time and that provides no indication of CNV. In contrast, LTA (after release in the area marked by the circle) reveals a CNV with its exact location. (C, D, E) A brightly fluorescent abnormal pattern of vessels (CNV) (arrowhead) and fluorescent patches (arrows) (obtained 50,110 and 430 msec, respectively, after the end of dye release). These patches evolve rapidly into a lobular pattern characteristic of chorioca-pillaris. (F) The fluorescent bolus clears from the normal choriocapillaris while remaining in the CNV (image obtained after 1.2 sec). Abbreviations LTA, laser-targeted angiography CNV, choroidal neovascularization. Source From Ref. 16, Figure 3.

Low Risk. CTA has a lower rate of patient discomfort, is less expensive, and has considerably lower risk of stroke and other vascular complications compared to conventional catheter angiography. It is also advantageous in situations when MR is contraindicated or cannot be performed. CTA is typically more readily available than MR, especially in emergency settings. CTA, unlike MRA, lends itself to the imaging of acutely ill patients, as there are no restrictions on the type and quantity of associated support equipment, such as intravenous pumps, ventilators, or monitoring hardware. Because CT scan acquisition is more rapid than that of MRA, CTA is less prone to motion artifact. When CTA is combined with CT perfusion (CTP) for the evaluation of acute stroke, quantitative perfusion data can also be obtained, which is not typically possible with MR perfusion imaging. 

Stroke can be evaluated with both conventional MRI and MR angiography sequences. The first section of this chapter discusses the appearance of stroke on conventional MR sequences (i.e., not diffusion or perfusion), while the second section discusses MR angiography and its role in evaluating stroke etiologies. 

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