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.