Arteriography of the carotid bifurcation: oblique projections

Atherosclerotic plaques may not be demonstrated adequately by standard anteroposterior (AP)-lateral projections of carotid arteriography. We evaluated selective carotid arteriography in oblique projections for 60 individual carotid arteries. Two neuroradiologists evaluated arteriograms in four separate sessions devoted to AP-lateral views alone and in combination with oblique projections. The lumen surface was characterized as "smooth," "irregular," or "ulcerated." When oblique projections were added to AP-lateral views, there was a significant shift of radiologic diagnosis from smooth to irregular or ulcerated. Addition of oblique projections to standard AP-lateral views increases the radiographic diagnosis of carotid artery lesions that may be the source of emboli.