Improvement of cervicocranial i.v. digital subtraction angiography with pixel remasking and cardiac gating.

A Philips DVI 2 apparatus* was used, and the technique has been described [8] . A total of 264 carotid bifurcations were studied retrospectively , 130 with and 134 without cardiac gating and postprocessing with pixel shift (Fig . 1 ). Only patients without renal failure or major cardiac disease were included. The ideal study of an area of interest consisted of two or more views with no movement of the patient or superimposition of vessels (Fig . 2). "See through " superimposition was accepted. The relevant carotid siphon was assessed in 31 patients whom the reviewer thought had a lesion of the common carotid bifurcation that was suitable for endarterectomy.