Spectral CT: Preliminary Studies in the Liver Cirrhosis

다국어 초록 (Multilingual Abstract)

Objective: To investigate the value of spectral CT imaging in the diagnosis and classification of liver cirrhosis during the arterial phase (AP) and portal venous phase (PVP).
Materials and Methods: Thirty-eight patients with liver cirrhosis (Child-Pugh class A/B/C: n = 10/14/14), and 43 patients with healthy livers, participated in this study. The researchers used abdominal spectral CT imaging during AP and PVP. Iodine concentration, derived from the iodine-based material-decomposition image and the iodine concentration ratio (ICratio) between AP and PVP, were obtained. Statistical analyses {two-sample t test, One-factor analysis of variance, and area under the receiver operating characteristic curve (A [z])} were performed.
Results: The mean normalized iodine concentration (NIC) (0.5 ± 0.12) during PVP in the control group was significantly higher than that in the study group (0.4 ± 0.10 on average, 0.4 ± 0.08 for Class A, 0.4 ± 0.15 for Class B, and 0.4 ± 0.06 for Class C) (All p < 0.05). Within the cirrhotic liver group, the mean NIC for Class C during the AP (0.1 ± 0.05) was significantly higher than NICs for Classes A (0.1 ± 0.06) and B (0.1 ± 0.03) (Both p < 0.05). The ICratio in the study group (0.4 ± 0.15), especially for Class C (0.5 ± 0.14), was higher than that in the control group (0.3 ± 0.15) (p < 0.05).The combination of NIC and ICratio showed high sensitivity and specificity for differentiating healthy liver from cirrhotic liver, especially in Class C cirrhotic liver.
Conclusion: Spectral CT Provides a quantitative method with which to analyze the cirrhotic liver, and shows the potential value in the classification of liver cirrhosis.

다국어 초록 (Multilingual Abstract)

Objective: To investigate the value of spectral CT imaging in the diagnosis and classification of liver cirrhosis during the arterial phase (AP) and portal venous phase (PVP).
Materials and Methods: Thirty-eight patients with liver cirrhosis (Child-Pugh class A/B/C: n = 10/14/14), and 43 patients with healthy livers, participated in this study. The researchers used abdominal spectral CT imaging during AP and PVP. Iodine concentration, derived from the iodine-based material-decomposition image and the iodine concentration ratio (ICratio) between AP and PVP, were obtained. Statistical analyses {two-sample t test, One-factor analysis of variance, and area under the receiver operating characteristic curve (A [z])} were performed.
Results: The mean normalized iodine concentration (NIC) (0.5 ± 0.12) during PVP in the control group was significantly higher than that in the study group (0.4 ± 0.10 on average, 0.4 ± 0.08 for Class A, 0.4 ± 0.15 for Class B, and 0.4 ± 0.06 for Class C) (All p < 0.05). Within the cirrhotic liver group, the mean NIC for Class C during the AP (0.1 ± 0.05) was significantly higher than NICs for Classes A (0.1 ± 0.06) and B (0.1 ± 0.03) (Both p < 0.05). The ICratio in the study group (0.4 ± 0.15), especially for Class C (0.5 ± 0.14), was higher than that in the control group (0.3 ± 0.15) (p < 0.05).The combination of NIC and ICratio showed high sensitivity and specificity for differentiating healthy liver from cirrhotic liver, especially in Class C cirrhotic liver.
Conclusion: Spectral CT Provides a quantitative method with which to analyze the cirrhotic liver, and shows the potential value in the classification of liver cirrhosis.

참고문헌 (Reference)

1 Chiro GD, "Tissue signatures with dual-energy computed tomography" 131 : 521-523, 1979

2 심재호, "Segmental Difference of the Hepatic Fibrosis from Chronic Viral Hepatitis due to Hepatitis B versus C Virus Infection: Comparison Using Dual Contrast Material-Enhanced MRI" 대한영상의학회 12 (12): 431-438, 2011

3 Jackson A, "Reproducibility of quantitative dynamic contrast-enhanced MRI in newly presenting glioma" 76 : 153-162, 2003

4 Padhani AR, "Reproducibility of quantitative dynamic MRI of normal human tissues" 15 : 143-153, 2002

5 Galbraith SM, "Reproducibility of dynamic contrast-enhanced MRI in human muscle and tumours: comparison of quantitative and semi-quantitative analysis" 15 : 132-142, 2002

6 Lautt WW, "Regulatory processes interacting to maintain hepatic blood flow constancy: vascular compliance, hepatic arterial buffer response, hepatorenal reflex, liver regeneration, escape from vasoconstriction" 37 : 891-903, 2007

7 Genant HK, "Quantitative bone mineral analysis using dual energy computed tomography" 12 : 545-551, 1977

8 Kelcz F, "Noise considerations in dual energy CT scanning" 6 : 418-425, 1979

9 Louis O, "Mineral content of vertebral trabecular bone: accuracy of dual energy quantitative computed tomography evaluated against neutron activation analysis and flame atomic absorption spectrometry" 15 : 35-39, 1994

10 Johnson TR, "Material differentiation by dual energy CT: initial experience" 17 : 1510-1517, 2007

11 Aoki T, "Intraoperative direct measurement of hepatic arterial buffer response in patients with or without cirrhosis" 11 : 684-691, 2005

12 Millner MR, "Extraction of information from CT scans at different energies" 6 : 70-71, 1979

13 Takahashi H, "Evaluation of quantitative portal venous, hepatic arterial, and total hepatic tissue blood flow using xenon CT in alcoholic liver cirrhosis: comparison with liver cirrhosis C" 31 (31): 43-48, 2007

14 Kalender WA, "Evaluation of a prototype dual-energy computed tomographic apparatus. I. Phantom studies" 13 : 334-339, 1986

15 Brenner D, "Estimated risks of radiation-induced fatal cancer from pediatric CT" 176 : 289-296, 2001

16 Alvarez RE, "Energy-selective reconstructions in X-ray computerized tomography" 21 : 733-744, 1976

17 Coursey CA, "Dual-energy multidetector CT: how does it work, what can it tell us, and when can we use it in abdominopelvic imaging?" 30 : 1037-1055, 2010

18 Yeh BM, "Dual-energy and low-kVp CT in the abdomen" 193 : 47-54, 2009

19 Lv P, "Differentiation of small hepatic hemangioma from small hepatocellular carcinoma: recently introduced spectral CT method" 259 : 720-729, 2011

20 Fleischmann D, "Computed tomography--old ideas and new technology" 21 : 510-517, 2011

21 Lee MH, "Comparison of surrogate serum markers and transient elastography (Fibroscan) for assessing cirrhosis in patients with chronic viral hepatitis" 55 : 3552-3560, 2010

22 Avrin DE, "Clinical application of Compton and photo-electric reconstruction in computed tomography: preliminary results" 13 : 217-222, 1978

23 Silva Jr RG, "Aspartate aminotransferase-to-platelet ratio index for fibrosis and cirrhosis prediction in chronic hepatitis C patients" 12 : 15-19, 2008

24 Hagiwara M, "Advanced liver fibrosis: diagnosis with 3D whole-liver perfusion MR imaging--initial experience" 246 : 926-934, 2008