Dual-source dual-energy CT in the evaluation of hepatic fractional extracellular space in cirrhosis.
BACKGROUND
One of the main features of liver fibrosis is the expansion of the interstitial space. All water-soluble CT contrast agents remain confined in the vascular and interstitial space constituting the fractional extracellular space (fECS). Indirect measure of its expansion can be quantified during equilibrium phase with CT. The goal of this prospective study was to assess the feasibility of dual-energy CT (DECT) with iodine quantification at equilibrium phase in the evaluation of significant fibrosis or cirrhosis.


METHODS
Thirty-eight cirrhotic patients (according to Child-Pugh and MELD scores), scheduled for liver CT, were enrolled in the study group. Twenty-four patients undergoing CT urography with a 10-min excretory phase were included in the control group. fECS was calculated as the ratio of the iodine concentration of liver parenchyma to that of the aorta, multiplied by 1 minus hematocrit.


RESULTS
Final study and control group were, respectively, composed of 22 and 20 patients. Mean hepatic fECS value was statistically greater in study group (P < 0.05). Positive correlation was observed between hepatic fECS value and MELD score (r = 0.64, P < 0.05). Analysis of variance showed statistical differences between control group and the Child-Pugh grades and between Child-Pugh A and B patients and Child-Pugh C patients (P < 0.05). ROC curves analysis yielded an optimum fECS cutoff value of 26.3% for differentiation of control group and cirrhotic patients (AUC 0.88; 86% sensitivity, 85% specificity).


CONCLUSIONS
Dual-source DECT is a feasible, noninvasive method for the assessment of significant liver fibrosis or cirrhosis.
['Bottari|Antonio|A|', 'Silipigni|Salvatore|S|', 'Carerj|Maria Ludovica|ML|', 'Cattafi|Antonino|A|', 'Maimone|Sergio|S|', 'Marino|Maria Adele|MA|', 'Mazziotti|Silvio|S|', 'Pitrone|Alessia|A|', 'Squadrito|Giovanni|G|', 'Ascenti|Giorgio|G|']
D000368:Aged D000369:Aged, 80 and over D016022:Case-Control Studies D005110:Extracellular Space D005240:Feasibility Studies D005260:Female D006801:Humans D008103:Liver Cirrhosis D008297:Male D008875:Middle Aged D011446:Prospective Studies D012372:ROC Curve D014057:Tomography, X-Ray Computed
Dual-source Dual-energy CT Fibrosis—cirrhosis Iodine concentration—fractional extracellular space