A comparison of non‐invasive methods in the assessment of extracranial carotid artery disease

The accuracy of four non‐invasive methods used in the evaluation of the extracranial carotid arterial system are presented. Three of the methods were flow dependent whilst the fourth was an ultrasonic imaging system. A consecutive series of 67 patients, (134 carotid arteries), having carotid angiography were investigated by means of carotid phonoangiography (CPA), oculoplethysmography (OPG), supra orbital Doppler (SOD) and B mode ultrasound scanning. The sensitivity of the B mode ultrasound was 81% with the OPG, CPA and Doppler method yielding sensitivites of 51%, 56% and 63% respectively. The specificity of both the OPG 95% and the Doppler 90% wqs high. The combined use of both B Mode ultrasound and OPG or Doppler will provide an improved overall accuracy in the assessment of extra cranial carotid stenosis.