A critical analysis of cerebral computed tomography scanning before elective carotid endarterectomy and its correlation to carotid stenosis.

BACKGROUND

Cerebral computed tomography (CT) scanning has been suggested to play a role in the management of patients before carotid endarterectomy (CEA). This prospective study analyzes the value of CT scanning before elective CEA and the correlation of CT findings to significant carotid stenosis.

METHODS

This study includes 131 consecutive patients considered for CEA during a 2-year period. All patients underwent carotid duplex ultrasonography, carotid arteriography, and CT scanning.

RESULTS

Eighty patients (61%) had transient ischemic attacks or prior strokes, and 51 (39%) had nonhemispheric symptoms or were asymptomatic. The CT scan was abnormal in 36 (27%) patients; however, no brain tumors or abnormalities to affect clinical management were revealed. Ninety-two CEAs were performed on 87 patients. Twenty-nine (32%) in the operative group had abnormal CT scans, but these did not influence operative decisions. On the basis of this rate of 0% of patients with CT findings to change surgical management in 92 cases, a maximum true rate of occurrence of up to 5% could be detected with alpha equals 0.05 by sampling a population of this size. Four patients (4%) had postoperative cerebral vascular accidents, and all of these had normal preoperative scans. Patients with 50% or more carotid stenosis on arteriogram were significantly more likely to have abnormal CT scans than patients with less than 50% stenosis (20% versus 7%, p = 0.0034). As carotid stenosis became more significant, the frequency of abnormal CT scans increased (p < 0.01). The cost of CT scanning was $66,089.50 in this study.

CONCLUSIONS

Significant carotid stenosis was associated with a higher frequency of abnormal CT scans; however, routine preoperative CT scanning was unnecessary before elective CEA.