Arteriography

Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins and the heart chambers. This is traditionally done by injecting a radio-opaque contrast agent into the blood vessel and imaging using X-ray based techniques such as fluoroscopy. So angiography consists of MRI, CT-Scan. . .
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Arteriography ArteriographyAngiography or arteriography is a medical imaging technique used to visualize theinside, or lumen, of blood vessels and organs of the body, with particular interestin the arteries, veins and the heart chambers. This is traditionally done b y injectinga radio-opaque contrast agent into the blood vessel and imaging using X -ray basedtechniques such as fluoroscopy. So angiography consists of MRI, CT -Scan. . .Many kinds of Angiograms, for exampleCoronary angiographyMicroangiographyNeuro-vascular angiographyPeripheral angiographyHow does anteriography play important role in diagnosis Gastrointestinalbleeding?Endoscopy for upper gastrointestinal bleeding and scintigraphy for lowergastrointestinal bleeding are important steps in the management and outcome oftranscatheter angiography. Computerized tomography angiography is a promisingtool for the treatment of both upper and lower GI bleeding, and this procedure hasbecome part of the imaging toolset. In addition, angiography performed outside ofworking hours had a higher rate of clinical success than the angiographiesperformed in working hours, most likely secondary to much ap propriate timing ofarteriogram in terms of critical bleeding intervals.In upper GI bleeding, arteriography is reserved for situations where brisk bleedingmakes endoscopy difficult.Multidetector computed tomography (CT) allows excellent visualization of boththe small and large bowel. Multiphasic multidetector CT allows directdemonstration of bleeding into the bowel and is helpful in the acute setting forvisualization of the bleeding source and its characterization. The additionalinformation provided by multidetector CT angiography before attempts attherapeutic angiographic procedures leads to faster selective catheterization ofbleeding vessels, thereby facilitating embolization.Some investigators advocate an upper GI endoscopy after colonoscopy yieldsnegative results, as about 10% of cases are ultimately found to involve an upperGI source of bleedingTherapeutic angiography is most strongly indicated in poor surgical candidates(elderly, severely ill patients) but is increasingly offered to all acute GI bleederswho continue to bleed after endoscopyIn small-bowel or lower GI bleeding, arteriography is utilized for both diagnosisand therapy of the acutely bleeding lesion, typically after initial localization withTRBC scanning or capsule endoscopy.Because colonoscopy of an unprepared colon is more difficult than upperendoscopy and lesions may be missed in a dirty colon because of poor preparationor active bleeding, the evaluation of lower GI bleeding is less straightforward.Angiography remains the best option in a patient in unstable condition and shouldbe performed in cases of massive bleedingThe three diagnostic modalities employed emergently for evaluation of acutelower GI bleeding are colonoscopy/sigmoidoscopy, technetium bleeding scans andangiography.As with upper GI bleeding, angiography is typically reserved for heavy bleeding(>1 ml/min), and has two advantages as a prec edent to surgery—it may stabilize apatient through vasopressin and embolization to avoid surgery or allow forelective surgery, and angiography can localize the bleeding site to reduce theextent of bowel resectionDiverticulosis has been implicated as the source of bleeding in as many as 60% ofcases of lower GI bleeding. The diverticula are more prevalent in the left orsigmoid colon, but positive arteriographic findings for bleeding localizes thebleeding to the right colon in 60% of cases.