Extracranial carotid doppler correlation to multidetector CT angiography in ischemic stroke patients

Abstract

The purpose of this study was to compare the diagnostic value of Color Doppler Ultrasound (CDUS), Computed Tomographic Angiography (CTA), and advantage of their combined use in defining the degree of stenosis and morphological character of atheromatous plaque in ischemic stroke patients. This was a cross-sectional study with a total of 60 patients having 120 carotid arteries were observed. The percentage of stenosis was measured at the narrowest point by modified NASCET criteria for both CDUS & CTA. Incidence of stroke was highest in the age group 50-70years with male population commonly affected. Frequency of carotid stenosis was more in male patients aged above 60 years. Hemiparesis was most common symptoms in stroke patients. The various risk factors of carotid atherosclerosis and stenosis included hypertension, diabetes mellitus, hyperlipidemia and cardiovascular disease. Atheromatous plaques with stenosis were most commonly found on right side. Carotid bifurcation was the common site for atheromatous plaque .There was significant correlation between Color Doppler Ultrasound and Computed Tomographic Angiography for detecting 70-100% stenosis. However CTA is more accurate in comparison to duplex ultrasonography in detecting 70-99% stenosis and total occlusion. There was no significant correlation between CDUS and CTA in detecting 20-49% stenosis. Duplex ultrasonography is more sensitive in detecting these lesions. Out of 49 plaques, in this study 11 were soft plaques, 26 were non-homogenous and 13 were ulcerative plaques. Color doppler has better role in plaque characterization. Besides degree of extracranial stenosis, length of the stenosis, site of intracranial stenosis and total number of stenotic sites are better assessed by CTA. Area of effected brain parenchyma and extent of collateral circulation are better assessed by CTA which aids in prognostic value. In conclusion, the advantage of the combined use of CDUS and the CTA in the identification and quantification of ICA stenosis is higher. However ultrasound had a better role in plaque characterization.