Inverse-direction scanning improves the image quality of whole carotid CT angiography with 64-MDCT.

Abstract Purpose The purpose of this prospective study was to clarify whether reducing the incidence of perivenous artifacts through craniocaudal scanning improves the quality of 64-multidetecter computed tomography (MDCT) angiography images of the whole carotid artery. Methods Forty patients underwent MDCT angiography in the caudocranial ( n  = 20) or craniocaudal ( n  = 20) direction in 2007. All patients were injected with 75 ml of contrast media followed by a 35-ml saline chaser bolus at 4.0 ml/s in the right antecubital vein. Maximum intensity projection (MIP) images were scored according to image quality on a scale of 1–5. Bilateral arterial and venous attenuation was measured on 10 separated slices. We compared the mean image quality score of the two groups (i.e. those scanned caudocranially and those scanned craniocaudally). We analyzed the correlation between vascular attenuation and mean image quality. Results Compared with the caudocranial group, the craniocaudal group had higher image quality scores (median, 3.70 vs. 3.40; 95% CI, 3.50–3.96 vs. 3.06–3.60; p p p R 2  = 0.42, p Conclusions Compared with conventional caudocranial scanning, craniocaudal scanning improves the image quality of 64-MDCT angiography images of the whole carotid artery.