Yining Wang MD, Presenter: Nothing to Disclose

Zhuhua Zhang MD, Abstract Co-Author: Nothing to Disclose

Zheng Yu Jin, Abstract Co-Author: Nothing to Disclose

Lingyan Kong MD, Abstract Co-Author: Nothing to Disclose

Lan Song MD, Abstract Co-Author: Nothing to Disclose

Songbai Lin, Abstract Co-Author: Nothing to Disclose

To compare the image quality and visibility of arteries of 64-slice coronary CT angiography (CTA) with those of 16-slice coronary CTA and to evaluate the diagnostic accuracy of 64-slice CT for assessing coronary artery stenosis.

100 patients (Group A, 67 male, aged 57±10) with suspected coronary artery disease (CAD) were examined by 64-slice CT (64 x 0.6 mm collimation, 0.33 s-rotation time, 120kV, 850mAs); 60 of whom also underwent conventional coronary angiography（CAG）. The other 100 patients (Group B, 63 male, aged 54±9) with suspected CAD were studied by 16-slice CT (16 x 0.75 mm collimation, 0.42 s-rotation time, 120kV, 500mAs). Patients with a heart rate above 70bpm received ß-blockers before the scan. Image quality was assessed using a 3-point grading scale from excellent (1) to non-assessable (3) and the rate of displayed coronary branches was calculated. All coronary segments were assessed for significant stenoses (>50% diameter reduction).

The mean heart rates of two groups showed no significant difference (61±8 bpm vs. 61±7 bpm, respectively). The mean scan time of Group A was significantly shorter than that of Group B (11.9±0.9s vs. 22.2±1.1s; P<0.01). In the evaluation of image quality, Group A resulted better than Group B (1.20±0.47 vs. 1.37±0.63; P<0.05). The visibility of proximal arteries between two groups was similar, while that of some distal arteries and small branches was found higher in Group A than in Group B (LAD distal 92% vs. 48%, OM1 93% vs. 84%, RVB 96% vs. 84%, P<0.05). Compared with CAG, the sensitivity, specificity, positive and negative predictive value of 64-slice CT to identify over 50% stenosis were 93%, 98%, 88％ and 98％, respectively.

With higher temporal and spatial resolution, 64-slice CT provides improved image quality and visibility of small branches as compared with 16-slice CT. 64-slice coronary CTA allows reliable non-invasive diagnosis of significant coronary artery stenosis..

64-slice CT provides higher image quality and visibility of arteries than 16-slice CT and is recommended in the initial evaluation of suspected coronary artery disease.

Wang, Y, Zhang, Z, Jin, Z, Kong, L, Song, L, Lin, S, Sixty-Four-slice CT Angiography of the Coronary Arteries: Comparison with 16-slice CT.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4435973.html