Concordance between carotid Doppler ultrasound and computerised tomographic angiography in predicting the need for surgery in carotid artery stenosis
Dr. Marguerite O'Callaghan
11 slide(s) – English – 2011-09-10
Aim: To compare the use of carotid Doppler ultrasound (CDUS) and computerized tomographic angiography (CTA) in assessing severity of internal carotid artery stenosis and evaluate their impact on the decision for carotid endarterectomy in the Mercy University Hospital (MUH), Cork.
Method: Computerised records of the radiology department in MUH were searched for patients who had undergone CTA from 2008-2010. 194 patients (388 carotids), were identified, 146 (75%) of whom also had CDUS. The degree of stenosis was categorised as normal/mild (<50%), moderate (50%–69%), severe (≥70-90%), near occlusion (> 90%), and complete occlusion. CTA was used as the “gold standard” investigation against which CDUS was compared.
Results: Overall concordance between CDUS and CTA was 64%. CDUS underestimated the degree of stenosis in 23.5% and overestimated in 12.2%. CTA altered the decision for surgery in 55/285 cases (19.3%). In 73% of cases this resulted in the patient being taken to surgery, in 27% (15/55) the plan to perform endarterectomy was abandoned.
Conclusion: CDUS is the primary noninvasive screening procedure for evaluation of ICA stenosis used in MUH. Our data suggests that CDUS is not sufficiently concordant with gold stardard investigation to warrant its sole use as a screening investigation.