Preliminary Application Of 16-slice Spiral CT In Detection Of Cervical Artery Stenosis

Purpose: We prospectively compared multi-slice spiral computed angiography (MSCTA) with catheter cervical angiography, to evaluate the accuracy and limitations of MSCTA in detection and categorization of cervical artery stenosis.Materials and Methods: 24 patients clinically diagnosed or suspected of cervical artery disorders underwent cervical angiography with a Lightspeed16 scanner (GE, U.S.A). The results were compared with catheter cervical angiography. The Z scanning span was from the aortic arch to about 2cm above the Willis cycle. 1.25mm thickness, 120-140kV, 300-400mA, table speed 13.5mm/s, 0.5s rotation, FOV 250mm. 80-100ml Ultravist300 was injected at a speed of 3.5ml/s via the cubical vein, time delayed 20s~22s. The raw data of MSCTA were reconstructed with 2D curve reformatting (2D-CPR), maximum intensity projection (MIP), volume rendering (VR) and virtual endoscopy (VE) techniques. MSCTA stenosis was determined by the percent of diameter reduction through the level of greatest narrowing according to the NASCET criteria on the 2D-CPR images. Two cardiac radiologists independently evaluate the MSCTA results. Chi-square test and kappa test were used to evaluate the concordance between the results of MSCTA and catheter cervical angiography.Results: All 168 segments of 24 patients' cervical arteries were welldisplayed. The overall concordance rate of MSCTA with catheter cervical angiography on displaying cervical artery stenosis was 96.4%. The sensitivity, specificity, PPV, NPV and accuracy were all of 100% for detecting and classifying severe stenosis (70%~99%) and occlusion. It corresponded to a sensitivity, specificity, accuracy, PPV and NPV of 85.7%> 99.3%> 94.7%> 97.9 and 97.6% for mid- and above stenosis (^ 30%) of cervical arteries.Conclusion: 16-slice CT enabled accurate visualization of severe stenosis and total occlusion of cervical arteries. The NPV of 16-slice CT for mid- and severe stenosis and total occlusion was high, which indicated that it may be used as an alternative for catheter cervical angiography on preliminary diagnosing and screening cervical artery stenosis.