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

Digital intravenous subtraction angiography (DIVSA) appears a promising and not highly invasive technique in the study of intracranial tumors and vascular lesions. In combination with computed tomography it should be sufficient in future for determining a preoperative tumourovascular balance. Already now it can be a valuable method in the screening for vascular malformation, in the postoperative evaluation of vascular intracranial lesions or after embolization of those lesions. In the study of the dural venous sinuses, DIVSA appears largely superior to conventional angiography. Advantages of the intravenous approach are the outpatient base, the low risk and low cost.--Low contrast dose and low pressure intraarterial subtraction technique is equivalent to conventional angiography with less risk and discomfort to the patient and resulting in considerable saving in cost.