Diagnosing and Quantification of Acute Alcohol Intoxication – Comparison of Dual-Energy CT with Biochemical Analysis: Initial Experience

Abstract

Purpose: To quantify the correlation between fat content of an acute alcohol intoxication and the difference of computer tomography attenuation value in dual-energy CT in comparison to biochemical triglyceride analysis and to evaluate qualitatively the value of DECT in the diagnosis of fatty liver caused by ethanol-dosage in rats.

Materials and Methods: DECT at 140 kV and 80 kV was performed on 20 rats before and two days after the administration of 3 ml of 50 % ethanol. The CT attenuation value in the livers at 140 kV, 80 kV and the differences between them in Hounsfield units (ΔH) were collected. Parts of the liver (100 mg) were measured in biochemical triglyceride analysis as the reference standard. A blood sample was also taken to measure specific liver enzymes.

Results: Linear correlation between biochemical triglyceride analysis and CT density of ΔH was found (r = 0.949). 140 kV attenuation data were between 44 HU and 61.3 HU, 80 kV attenuation data were between 58.4 HU and 64.7 HU, and ΔH data were between 3.4 HU and 14.4 HU (p ≤ 0.037). The biochemical triglyceride analysis data were between 7.1 mg/g and 41.1 mg/g. The hepatic enzymes serum aspartate (ASAT) aminotransferase and alanine aminotransferase (ALAT) were elevated in all rats. ASAT correlated directly with ΔHU (r = –0.86).

Conclusion: DECT provides a non-invasive method to determine and evaluate hepatic fat content after acute alcohol intoxication. It provides the possibility to detect and quantify the hepatic fat content of liver graft.

Zusammenfassung

Ziel: Quantifizierung des Fettanteils einer akuten Alkoholvergiftung anhand von Messungen mit der Dual-Energy-Computer-Tomografie (DECT) und der biochemischen Triglyceride-Analyse sowie qualitative Bewertung der DECT als diagnostisches Mittel zur Erkennung einer Fettleber bei Ratten verursacht durch Ethanolgabe.

Material und Methoden: Messungen der DECT wurden bei 140 kV und 80 kV bei 20 Ratten 2 Tage nach Applikation von 3 ml 50 %igem Ethanol durchgeführt. Die CT-Werte bei 140 kV, 80 kV und deren Differenz der Hounsfield-Einheiten (ΔH) wurden bestimmt. Proben der Leber (100 mg) wurden mit der biochemischen Triglyceride-Analyse als Goldstandard gemessen. Zur Auswertung bestimmter Leberenzyme wurde eine Blutprobe genommen.

Ergebnisse: Eine lineare Beziehung zwischen der biochemischen Triglyceride-Analyse und der CT-Dichte von ΔH war festzustellen (r = 0,949). Die Werte bei 140 kV lagen zwischen 44 HU und 61,3 HU, bei 80 kV lagen die Werte zwischen 58,4 HU und 64,7 HU und bei ΔH zwischen 3,4 HU und 14,4 HU (p ≤ 0,037). Die Werte der biochemischen Triglyceride-Analyse lagen zwischen 7,1 mg/g und 41,1 mg/g. Die Werte der Leberenzyme Aspartat-Aminotransferase (ASAT) und Alanin-Aminotransferase (ALAT) waren bei allen Ratten erhöht. ASAT korrelierte direkt mit ΔHU (r = –0,86).

Schlussfolgerung: Die DECT stellt eine nicht invasive Methode zur Feststellung und Bewertung des hepatischen Fettgehalts nach akuter Alkoholvergiftung dar. Es bietet die Möglichkeit, den Fettgehalt von Transplantatlebern quantitativ zu bestimmen.

Key words

abdomen - CT - CT-quantitative - biological effects

• References

• 1 Rehm J et al. Global burden of disease and injury and economic cost attributable to alcohol use and alcohol-use disorders. Lancet 2009; 373: 2223-2233
• 2 Sun W et al. Moderate alcohol use, health status, and mortality in a prospective Chinese elderly cohort. Ann Epidemiol 2009; 19: 396-403
• 3 Mathurin P, Deltenre P. Effect of binge drinking on the liver: an alarming public health issue?. Gut 2009; 58: 613-617
• 4 Rosen BR et al. Proton chemical shift imaging: an evaluation of its clinical potential using an in vivo fatty liver model. Radiology 1985; 154: 469-472
• 5 Ricci C et al. Noninvasive in vivo quantitative assessment of fat content in human liver. J Hepatol 1997; 27: 108-113
• 6 Ducommun JC et al. The relation of liver fat to computed tomography numbers: apreliminary experimental study in rabbits. Radiology 1979; 130: 511-513
• 7 Cann CE. Quantitative CT for determination of bone mineral density: a review. Radiology 1988; 166: 509-522
• 8 Levi C et al. The unreliability of CT numbers as absolute values. Am J Roentgenol 1982; 139: 443-447
• 9 Robinson E et al. Dual source dual energy MDCT: comparison of 80 kVp and weighted average 120 kVp data for conspicuity of hypo-vascular liver metastases. Invest Radiol 2010; 45: 413-418
• 10 Ueno T et al. Therapeutic effects of restricted diet and exercise in obese patients with fatty liver. J Hepatol 1997; 27: 103-107
• 11 Folch J, Lees M, Sloane Stanley GH. A simple method for the isolation and purification of total lipides from animal tissues. J Biol Chem 1957; 226: 497-509
• 12 Boyce CJ et al. Hepatic steatosis (fatty liver disease) in asymptomatic adults identified by unenhanced low-dose CT. Am J Roentgenol 2010; 194: 623-628
• 13 Zachrisson H et al. Soft tissue discrimination ex vivo by dual energy computed tomography. Eur J Radiol 2010; epub; 75: e124-e128
• 14 Kodama Y et al. Comparison of CT methods for determining the fat content of the liver. Am J Roentgenol 2007; 188: 1307-1312
• 15 Teli MR et al. Determinants of progression to cirrhosis or fibrosis in pure alcoholic fatty liver. Lancet 1995; 346: 987-990
• 16 Bohte AE et al. The diagnostic accuracy of US, CT, MRI and (1)H-MRS for the evaluation of hepatic steatosis compared with liver biopsy: a meta-analysis. Eur Radiol 2010; DOI: 10.1007/s00330-010-1905-5.
• 17 Davidson LE et al. Protocol for measurement of liver fat by computed tomography. J Appl Physiol 2006; 100: 864-868
• 18 Raptopoulos V et al. Value of dual-energy CT in differentiating focal fatty infiltration of the liver from low-density masses. Am J Roentgenol 1991; 157: 721-725
• 19 Wang B et al. Quantitative diagnosis of fatty liver with dual-energy CT. An experimental study in rabbits. Acta Radiol 2003; 44: 92-97
• 20 Dam-Larsen S et al. Final results of a long-term, clinical follow-up in fatty liver patients. Scand J Gastroenterol 2009; 44: 1236-1243
• 21 Niemelä O, Alatalo P. Biomarkers of alcohol consumption and related liver disease. Scand J Clin Lab Invest 2010; 70: 305-312
• 22 Neumann T, Spies C. Use of biomarkers for alcohol use disorders in clinical practice. Addiction 2003; 98: 81-91
• 23 Park SH et al. Macrovesicular hepatic steatosis in living liver donors: use of CT for quantitative and qualitative assessment. Radiology 2006; 239: 105-112
• 24 Charatcharoenwitthaya P, Lindor KD. Role of radiologic modalities in the management of non-alcoholic steatohepatitis. Clin Liver Dis 2007; 11: 37-54, viii
• 25 Saadeh S et al. The utility of radiological imaging in nonalcoholic fatty liver disease. Gastroenterology 2002; 123: 745-750
• 26 Zhang LJ et al. Liver virtual non-enhanced CT with dual-source, dual-energy CT: a preliminary study. Eur Radiol 2010; 20: 2257-2264
• 27 De Cecco CN et al. Dual energy CT (DECT) of the liver: conventional versus virtual unenhanced images. Eur Radiol 2010; 20: 2870-2875
• 28 Kamel IR et al. Impact of multidetector CT on donor selection and surgical planning before living adult right lobe liver transplantation. Am J Roentgenol 2001; 176: 193-200
• 29 Zorzano A, Herrera E. In vivo ethanol elimination in man, monkey and rat: a lack of relationship between the ethanol metabolism and the hepatic activities of alcohol and aldehyde dehydrogenases. Life Sci 1990; 46: 223-230
• 30 Reeder SB, Ranallo F, Taylor AJ. CT and MRI for determining hepatic fat content. Am J Roentgenol 2008; 190: W167 ; author reply W168