Preoperative imaging of the carotid bifurcation. Current trends

There is disagreement about the most appropriate imaging examination necessary for the preoperative assessment of the carotid bifurcation. Our objective was to find out the preferences of clinicians on this issue in one large hospital. And to determine whether and how these preferences have changed over time.

Observational, retrospective study.

Large metropolitan and university affiliated hospital. Numbers of patients per year who underwent carotid endarterectomy during 1990-1998. Numbers of patients per year who had conventional catheter carotid angiography during the same period. Assessment of the nature of preoperative carotid imaging in a sample of 400 patients (100 each in 1990, 1993, 1996 and 1998). Analysis of the types of imaging examinations by year and determination of underlying trends.

Number of carotid angiograms expressed as a percentage of carotid endarterectomies performed each year. Types of preoperative imaging examinations of the carotids and changes over time.

The number of preoperative conventional catheter angiograms decreased over time. In 1990 angiography was performed in 86% of carotid endarterectomies. In 1998 the proportion decreased to 16% (p<0.05). Conversely, the proportion of endarterectomies carried out based solely on ultrasonography increased from 6% in 1990 to 56% in 1998 (p<0.05). The proportion of endarterectomies performed based on the combined findings of ultrasound and magnetic resonance angiography increased from 3% in 1990 to 56% in 1996 and to 26% in 1998. Computed tomoangiography has not become popular. The observed reduction in the number of preoperative conventional carotid angiograms was independent of the presence/absence of symptoms, the level of serum creatinine, the subspecialty of the surgeon (vascular surgery vs neurosurgery) and the individual surgeon involved.

In one large university affiliated hospital the trend in the preoperative imaging of the carotid arteries is moving away from conventional catheter angiography. There is increasing application of ultrasound combined with magnetic resonance angiography and a more pronounced trend towards the performance of carotid endarterectomy based only on ultrasonography.