Effect of different scan parameters and algorithm on detection of iron deposition coexiting in fat by dual source CT
10.3760/cma.j.issn.1005-1201.2014.04.016
- VernacularTitle:双能CT扫描参数和算法对定量检测伴脂肪沉积肝脏铁含量影响的实验研究
- Author:
Jing MA
;
Haipeng DONG
;
Qiong SONG
;
Naiyi ZHU
;
Wenjie YANG
;
Liang HOU
;
Fuhua YAN
- Publication Type:Journal Article
- Keywords:
Liver;
Fats;
Iron;
Tomography,X-ray computed
- From:
Chinese Journal of Radiology
2014;48(4):333-336
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of different scan parameters and algorithm on detection of iron deposition with coexsiting fat by dual soure CT.Methods One ml homogenate of normal rat liver tissues and 1 ml iron dextran solution with different concentrations (50.000,25.000,12.500,6.250,3.125,and 1.560 mg/ml) were fully mixed respectively.The 6 test tubes were scanned by dual source CT in the mode of dual energy to gain the iron specific slope.Different concentrations of dextran iron(50,40,30,20,10,and 5 mg/ml),triglyceride(volume percent were 60％,30％,and 10％,respectively),and homogenate of normal rat liver tissues were mixed.All 18 tubes were scanned by dual source CT with 80-140 kVp and 100-140 kVp,and all these images were reconstructed by filtered back projection (FBP) and singogram affirmed iterative reconstruction(SAFIRE).Raw data were reconstructed by filtering and iterative method.△H value (△H =CT value low kVp-CT valuehigh kVp) and overlay value of three substances decomposition algorithm were measured and analyzed by t test.The Spearmen correlation was applied in iron concentration and measured values.Results Iron specific slope was found to be 1.9392.When 80-140 kVp and 100-140 kVp were applied,△H values were (198 ± 28) and (152 ± 18) HU by using FBP reconstruction,and △H values were (191 ± 23) and (149 ± 17) HU by using SAFIRE reconstruction.The differences were statistically significant(t =-2.934 and-3.492,P =0.032 and 0.017).Overlay values were (381 ±54) and (236 ±31) HU by using FBP reconstruction,and overlay values were (399 ±53) and (276 ± 43) HU by using SAFIRE reconstruction.The differences were also statistically significant (t =-5.739 and-7.949,P =0.002 and 0.001).Under the same energy portfolio but different reconstruction,both △H and overlay value showed no differences (P ＞ 0.05).Except for the conditions with 100-140 kVp tube voltage,△H had no correlation with iron solution concentration (P ＞ 0.05) under either FBP or SAFIRE reconstruction.When other reconstruction methods and tube voltage combination were used,overlay or △H value showed correlation with iron solution concentrations (r value ranged from 0.959 to 0.997,P values ＜ 0.01).Conclusions Different energy portfolios of dual source CT will act on the measured value of iron deposition.The measured values will not be affected by ways of reconstruction.For the detection of iron coexisting in fat,overlay values of material decomposition algorithm is better.
