Digital intravenous and intraarterial subtraction angiography. Applications to the intracranial vascular system

The place of digital intravenous angiography in cerebral infarcts

The authors describe their technique of intravenous digital subtraction angiography (IVDSA) and discuss the results in cerebral infarcts. IVDSA is a good first stage examination for the recognition of stenosis or occlusion of cervical vessels to the brain, as it is an only marginally invasive and easy technique. It is, however, good neither for the study of focal cervical not of intracranial areas.

Applications of digital subtraction angiography in cardiovascular diagnosis

Both intravenous and intra-arterial DSA have widespread applications in the field of cardiovascular diagnosis. The definition of carotid artery stenosis or severe peripheral vascular disease in the patient undergoing coronary artery bypass surgery might dictate the need for simultaneous carotid and coronary artery surgery or demonstrate the best route for insertion of an intra-aortic balloon. DSA also might find further application in the definition of thoracic aortic dissection, thoracic aortic trauma, and coarctation of the thoracic aorta, as well as in showing the adequacy of repair of thoracic coarctation in patients who remain hypertensive postoperatively. Left ventricular imaging using intravenous or intraventricular injections of contrast material provides an accurate method of calculating ejection fraction and an excellent picture of left ventricular wall motion. In addition, because smaller amounts of contrast material may be used for intraventricular infections, patients with renal failure or severe impairment of the left ventricle might fare better with the reduced contrast load. Multiple ventriculograms can be performed following interventions such as pacing or exercise to allow a more adequate definition of left ventricular performance. Intravenous DSA still has not achieved satisfactory visualization of the coronary arteries or coronary artery bypass grafts. However, aortic root injections of contrast material can provide adequate definition of these structures and has been recommended as a screening technique for coronary disease in patients undergoing arteriography for other vascular disease. Current work on the development of DSA techniques for the quantitation of coronary artery blood flow and myocardial perfusion is quite promising. Accurate, reproducible measurement of coronary artery blood flow, patterns of myocardial perfusion, and areas of myocardium supplied by specific coronary vessels with obstructions may soon provide physiologic information about anatomically defined coronary artery disease. A variety of congenital heart defects have been defined by intravenous DSA. Shunt lesions such as atrial septal defects, ventricular septal defects, and patent ductus arteriosus have been defined anatomically, and the severity of their shunts has been estimated by placing windows of interest over the various cardiac chambers. It is possible that certain congenital malformations might be studied adequately by intravenous DSA, eliminating the need for cardiac catheterization.(ABSTRACT TRUNCATED AT 400 WORDS)

[Preoperative intra-arterial digital subtraction angiography in aortoiliac vascular occlusion]

Sixteen patients with advanced aorto-iliac occlusive disease were examined with digital subtraction angiography (DSA) using intraarterial injection of contrast medium. The preoperative evaluation of the vessels distal to the occlusion and the visualization of the femoral and popliteal arteries were successfully performed with intraarterial DSA. As compared to conventional angiography the marked contrast enhancement of DSA is demonstrated. Less spatial resolution of DSA lacks importance as the herein discussed topic is concerned. The limited size (23 cm) of the image intensifier of the X-ray equipment used was a major drawback of the method. Using intravenous DSA aorto-iliac occlusion can be shown. In patients with long range vascular occlusion and sparse development of collaterals only intraarterial DSA can demonstrate the run-off vessels including the trifurcation of the popliteal artery.