An asymptomatic old patient presents with bruit in the carotid artery. Which of the following is the investigation of choice?
Bruit over carotid artery suggests carotid artery stenosis.
Duplex scanning (B-mode scan and doppler ultrasonic velocimetry) is the method of choice for assessing the degree of carotid stenosis.
Doppler ultrasonography
Internal carotid angiography
Aortic arch angiography
Spiral CT angiography