[Combined use of wide-detector and adaptive statistical iterative reconstruction-V technique in abdominal CT with low radiation dose].
Zhonghua Yi Xue Za Zhi
; 97(45): 3567-3572, 2017 Dec 05.
Article
em Zh
| MEDLINE
| ID: mdl-29275597
ABSTRACT
Objective:
To investigate the image quality and radiation dose with wide-detector(80 mm) and adaptive statistical iterative reconstruction-V (ASIR-V) technique at abdominal contrast enhanced CT scan.Methods:
In the first phantom experiment part, the percentage of ASIR-V for half dose of combined wide detector with ASIR-V technique as compared with standard-detector (40 mm) technique was determined. The human experiment was performed based on the phantom study, 160 patients underwent contrast-enhanced abdominal CT scan were prospectively collected and divided into the control group (n=40) with image reconstruction using 40% ASIR (group A) and the study group (n=120) with random number table. According to pre-ASIR-V percentage, the study group was assigned into three groups[40 cases in each group, group B 0 pre-ASIR-V scan with image reconstruction of 0-100% post-ASIR-V (interval 10%, subgroups B0-B10); group C 20% pre-ASIR-V with 20%, 40% and 60% post-ASIR-V (subgroups C1-C3); group D 40%pre-ASIR-V with 40% and 60% post-ASIR-V (subgroups D1-D2)]. Image noise, CT attenuation values and CNR of the liver, pancreas, aorta and portal vein were compared by using two sample t test and One-way ANOVA. Qualitative visual parameters (overall image quality as graded on a 5-point scale) was compared by Mann-Whitney U test and Kruskal-Wallis H test.Results:
The phantom experiment showed that the percentage of pre-ASIR-V for half dose was 40%. With the 40% pre-ASIR-V, radiation dose in the study group was reduced by 35.5% as compared with the control group. Image noise in the subgroups of B2-B10, C2-C3 and D1-D2 were lower (t=-14.681--3.046, all P<0.05) while CNR in the subgroups of B4-B10, C2-3 and D1-D2 were higher(t=2.048-9.248, all P<0.05)than those in group A, except the CNR of liver in the arterial phase (AP) in C2, D1 and D2 and the CNR of pancreas in AP in D1 (t=0.574-1.327, all P>0.05). The subjective image quality scores increased gradually in the range of 0-60% post-ASIR-V and decreased with post-ASIR-V larger than 70%. The overall image quality of subgroup B3-B8, C2-C3 and D1-D2 were higher than that in group A (Z=-2.229--6.533, all P<0.05).Conclusion:
Compared with stand-detector together with ASIR technique, wide-detector combined with 40% pre-ASIR-V technique with 60% post-ASIR-V image reconstruction can reduce radiation dose while maintain good overall image quality.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doses de Radiação
/
Interpretação de Imagem Radiográfica Assistida por Computador
/
Abdome
Tipo de estudo:
Clinical_trials
/
Qualitative_research
Limite:
Humans
Idioma:
Zh
Ano de publicação:
2017
Tipo de documento:
Article