Nouvelle methode d'angiographie cerebrale simultanee totale par injection intraveineuse rapide

Digital subtraction angiography (DSA) in neuroradiology

DSA ranks among the modern imaging procedures which owe their development to the advances made in computer technology. Thanks to i.v. contrast injection, it has become possible to evaluate a lesion in the cervical vessels in at least 80% of cases and in 60% of cases when intracranial vessels are concerned. Intra-arterial contrast injection renders the diagnostic yield of DSA equal to that of conventional angiography with the benefit that the required contrast volumes are low and that the catheter need not always be placed selectively. Intravenous contrast injection is required with patients advanced in age, when critical cardiovascular conditions prevail, when the arterial access routes are completely occluded or in the case of postoperative checks of the cervical vessels. Although its field of application remains restricted, particularly in the case of intravenous contrast injection, the clinical application of DSA appears well established and its advantages are undisputed. Examples are given to demonstrate the clinical boundaries set to this new imaging procedure based on i.v. and intra-arterial contrast injection.

Intravenous arteriography in the preoperative evaluation of advanced atherosclerosis

Intravenous arteriography may be used as an alternative to translumbar or transaxillary angiography in cases with occlusion or severe stenosis of the aorta or iliac arteries, to determine the extension of the disease. During a 10-year period the method was used in 117 patients. For the examination, 80 to 100 ml of contrast medium was injected into the right atrium and after a delay of 10 to 20 seconds the lumbar aorta, iliac and femoral arteries were demonstrated. The quality of the examination was excellent or good in 92 per cent. No complications occurred. In 19 patients a continuous pressure recording was made in the main pulmonary artery. The pulmonary artery pressure increased to a significantly higher degree after contrast medium injection than after injection of the same amount of isotone saline. In all patients the pressure returned to normal within 4 minutes.

Digital video subtraction angiography of the cervical and cerebral vasculature

A digital video subtraction angiography unit developed at the University of Arizona is described. The system allows the angiographic evaluation of the cervical and cerebral vasculature by means of intravenous injection of contrast material. The procedure is performed on outpatients and is reliable, safe, and economical. The authors have evaluated suspected arterial and venous occlusive disease, certain aneurysms and tumors, and postoperative results of vascular bypass procedures and aneurysm clipping. The clinical application of the technique is shown with appropriate case presentations.

[CONTRIBUTION TO THE STUDY OF THE ARTERIAL SUPPLY OF THE BRAIN. THORACOCERVICAL ARTERIOGRAPHY USING PULMONARY HYPERPRESSURE]

Êste trabalho versa sôbre a visibilização das fontes arteriais do encéfalo mediante injeção de substância radiopaca por via carotídea, graças ao bloqueio circulatório resultante do aumento da pressão intrapulmonar. São consideradas fontes arteriais encefálicas as carótidas comuns, as artérias vertebrais, o tronco braquiocefálico e os segmentos pré-vertebrais das artérias subclávias. A punção arterial, transcutânea, é feita em uma das carótidas comuns ou, excepcionalmente, no tronco braquiocefálico ou na artéria subclávia (segmento pré-vertebral). Para aumentar a pressão intrapulmonar, o pulmão do paciente é insuflado com oxigênio através da sonda traqueal munida de "cuff". Uma válvula, colocada entre a fonte de oxigênio e a sonda traqueal, permite controlar a pressão intrapulmonar, que não deve exceder a 75 mm Hg. A injeção de substância contrastante é feita em 2 a 3 segundos e deve ser iniciada assim que a pressão intrapulmonar atinge o valor de 75 mm Hg, prèviamente fixado na válvula. A compressão digital da carótida a jusante do ponto de inserção da agulha tem sido recurso complementar eficiente, proporcionando visibilização de tôdas as artérias da região de modo nítido e constante. São expostos os resultados de 46 exames realizados segundo a técnica descrita. Nenhum caso de acidente foi registrado. Embora haja ainda alguns pontos obscuros e pormenores de técnica que devem ser aperfeiçoados ou modificados, a simplicidade e a segurança do método permitem situá-lo em posição vantajosa entre seus congêneres.