Dual source CT angiography of carotid stenoses in comparison to MR angiography and duplex sonography [Dual-Source CT-Angiographie von Karotisstenosen im Vergleich zu MR-Angiographie und Duplexsonographie]

Aim: The aim of this study was to evaluate the accuracy of dual source CT angiography of the carotid artery in comparison with MR angiography and color-coded duplex ultrasound (US). Material and methods: From 15 symptomatic patients 30 carotid arteries were evaluated for the degree of stenosis following the NASCET criteria for angiography and the DEGUM criteria for sonography. Each patient was examined using duplex ultrasound, 3T MR angiography and contrast-enhanced dual source CT angiography (DSCT) (tube A 140 kV, 55 mA, tube B 80 kV, 230 mA; 64×0.6 mm coll, pitch 0.65 rot. 0.33 s) of the extracranial carotid artery. Images were reconstructed in 1 mm section thickness and direct bone removal was performed for optimal visualization after the scan. All dual source CT and MR angiography images were evaluated and measured by the same experienced radiologist and all duplex ultrasound results by the same neurologist. Measurement results were compared and correlated. Results: The mean degree of stenosis was 48% by CT (SD 35%), 49% by MR (SD 38%) and 47% by US (SD 41%). There was no statistically significant difference in stenosis evaluation between CT and MR (p=0.83) or between CT and US (p=0.75). The correlation coefficient between CT and MR was r=0.8327, between CT and US r=0.8424 and between US and MR r=0.8260. Conclusion: Dual source CT evaluation of the carotid arteries allows a reliable measurement of carotid artery stenosis. Results are comparable to MR angiography and US. © 2009 Springer Medizin Verlag.