Image quality of low-tube-voltage and high-pitch dual-energy CT angiography of the head and neck arteries using photon detectors with iterative reconstruction methods: compared with conventional detectors

• DOI: 10.3760/cma.j.issn.1005-1201.2014.07.005
• Publication Date: 2014-07-10
• Authors: Yu Chen; Xue Huadan; Zhang Daming; Hao Sun; Xuan Wang; Zhang Zhuhua; Sun Zhaoyong; Yun Wang; Zhengyu Jin
• Keywords: Rotational angiography

Objective To detect the image quality of dual-energy CT angiography(CTA) head and neck arteries with low tube voltage,high pitch iterative reconstruction(IR) using photon detectors,compared conventional detectors.Methods CTA was performed on 50 consecutive patients suspected or previously diagnosed arterial diseases neck.Patients were randomized to one two groups stellar detectors(Group A,n=24) detectors (Group B,n=26).CTA 128-slice dual source systems detectors,respectively.Dual-enery voltage settings 140 kVp/80 kVp in A/B,and a high 1.2.All acquisitions reconstructed IR,1.0 mm thickness,DE composition=0.6.CTDIvol(CT dose index volume) DLP(dose-length product) recorded.Effective dose(ED) calculated.Quantitative measurements each IR sequence(140kVp,80kVp mixed energy) 1.00 enhanced MPR(multi planar reformations) images as follows:(1) level aortic artery(AA),the largest anteroposterior diameter chest(R 1AP),CT attenuation values standard deviation (SD) AA; (2) common carotid artery(CCA) bifurcation,the auteroposterior leftright diameter(R2AP,R2LR),CT SD CCA,sternocleidomastoid muscle(SCM),ventral air contralateral side contrast injection; (3) clinoid segment internal artery(C5),the left-right diameter(R3AP,R3LR),CT C5 brain stem.CNR AA,CCA calculated CNR.Qualitative assessments for based on:noise parenchyma,sharpness subarachnoid space margins,grey matter-white matter differentiation visualization middle cerebral arteries.t test,Wilcoxon nonparametric test Mann-Whitney U used compare difference between groups.Results There no significant ED group A B(t=0.93,P=0.35),CTDIvol higher Group A(3.85 ±0.17) mGy,compared B(3.74±0.18) mGy(t=2.17,P=0.03).The AA CCA A[(25.8±4.3),(17.7±7.4) HU] than that B [(22.8 ± 3.6),(13.6 5.7) HU].The indicated statistical significance(t=2.73,P=0.01 ; t=2.24,P=0.03).The stem IR,80 mixed-energy were(17.1± 2.6),21.0(19.4,22.7) 14.8(13.4,16.4) HU,and lower B(18.7±2.3),24.8(21.6,26.8),16.6(14.9,18.5) HU.The significance(t=-2.30,P=0.03;Z=-3.18,P=0.01 ;Z=-2.34,P=0.02).There qualitative groups(P＞0.05).Conclusions Stellar results noise not increase effective low-tube-voltage high-pitch DE neck,with reconstraction method,compared detectors.

Key words: Tomography,X-ray computed; Angiography; Radiation dosage; Comparative study