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Echoencephalography with simultaneous A- and B- mode display.

used whenever there was the likelihood of angiography and a mobile image intensifier linked to a videotape recorder was available. Catheterization angiography was favoured. Four instances in which this technique was used were described to illustrate its value. 1. For localization of intracranial vascular lesionsfor example, a small, deeply placed arteriovenous malformation. 2. To increase the precision and to reduce the time taken in dissecting the lesion. 3. To check the stages of a procedure, such as embolization of a carotico-cavernous fistula. 4. To obtain immediate information on the efficacy of the surgical procedure, particularly (a) where the surgery was of more than usual magnitude, as in the anterior approach to an aneurysm of the basilar artery, and (b) where there was reason to suspect inadequate occlusion, as in some cases of aneurysm. 5. The immediate recognition of complications of surgery-for example, the inadvertent occlusion of a major vessel with an aneurysm clip. The authors mentioned the following potential disadvantages of operative angiography: (1) an increased operating time (angiography took 20 to 70 minutes) which might be offset by facility in localizing the lesion; (2) the recognized hazards of angiography; (3) an increase in theatre personnel and equipment. They concluded, in the light of their experience of this technique and from the reports of others, that it could play an important part in the surgical management of A-V malformations, aneurysm, carotico-cavemous fistula, obliterative vascular disease, and of vascular tumours.