POSTERS comparable to TE only for the prediction of severe fibrosis and cirrhosis, whereas for earlier stages, TE performs better. 405 SUPERSONIC SHEAR IMAGING IS A NEW POTENT MORPHOLOGICAL NON-INVASIVE TECHNIQUE TO ASSESS OF LIVER FIBROSIS. PART II: COMPARISON WITH FIBROSCAN E. Bavu 1 , J.-L. Gennisson 1 , V. Mallet 2 , B.-F. Osmanski 3 , M. Couade 3 , J. Bercoff 3 , M. Fink 1 , P. Sogni 2 , A. Vallet-Pichard 2 , B. Nalpas 2 , M. Tanter 1 , S. Pol 2 . 1 Laboratoire Ondes et Acoustique, ESPCI ParisTech, CNRS UMR7587, INSERM U979, 2 H´ epatologie, Universit´ e Paris-Descartes, APHP, INSERM U. 567, Paris, 3 SuperSonic Imagine, Aix en Provence, France E-mail: vincent.mallet@cch.aphp.fr Background: Liver stiffness averaged along an ultrasonic A-line at 50 Hz (Fibroscan ® ) has a rather good diagnostic accuracy to distinguish mild (F0–F1) from severe fibrosis (F3–F4) in chronic liver disease (CLD). Supersonic Shear Imaging (SSI) is a real-time device coupled to an ultrasound imaging system that assesses the elasticity of a large liver area with a large frequency bandwidth. SSI is highly accurate to decipher fibrosis stages in CLD, including intermediate levels of fibrosis. Aim: To compare the accuracy of SSI and Fibroscan ® (FS) to delineate fibrosis in chronic liver disease. Patients: 104 patients with chronic liver disease (89% HCV, 7% HBV, 4% Alcoholic cirrhosis) who gave informed consent. Methods: All patients underwent SSI and FS. Hepatic fibrosis stage (F[0–4] with 4 representing cirrhosis) was determined retrospectively on the basis of histology, on a diagnosis algorithm based on three non-invasive markers performed the day of SSI (FIB-4, APRI and FORNS) and on clinical history. The performances of SSI and FS were compared with ROC (receiver operator characteristic) curve analysis and with one-way analysis of variance (Anova). Comparison between AUROC curves was performed with the Delong test. Results: The repartition of fibrosis among patients was F0–F1 = 43, F2 = 22, F3 = 17, F4 = 22. There was a better correlation between Fibrosis staging and elasticity assessments with SSI (P ≈ 10 −16 ) than with FS (P ≈ 10 −12 ). The AUROC of SSI and FS were respectively 0.95 (95% confidence interval [CI:] 0.90–0.99) and 0.89 (95% CI: 0.84– 0.96) for patients with F ≥ 2 (P = 0.04), 0.96 (95% CI: 0.91–0.99) and 0.94 (95% CI: 0.87–0.98) for patients with F ≥ 3 (P = 0.25), and 0.97 (95% CI: 0.95–1.00) and 0.94 (95% CI: 0.88–0.98) for patients with F = 4 (P = 0.16). Conclusion: The accuracy of SSI is better than FS to delineate fibrosis in CLD, especially for intermediate stages (F2). SSI is an excellent method to identify patients with chronic liver disease that are to treat (F2–F4) and those that are not to treat. 406 SUPERSONIC SHEAR IMAGING IS A NEW POTENT MORPHOLOGICAL NON-INVASIVE TECHNIQUE TO ASSESS LIVER FIBROSIS. PART I: TECHNICAL FEASABILITY E. Bavu 1 , J.-L. Gennisson 1 , V. Mallet 2 , B.-F. Osmanski 3 , M. Couade 3 , J. Bercoff 3 , M. Fink 1 , P. Sogni 2 , A. Vallet-Pichard 2 , B. Nalpas 4 , M. Tanter 1 , S. Pol 2 . 1 Laboratoire Ondes et Acoustique, ESPCI ParisTech, CNRS UMR7587, INSERM U979, 2 H´ epatologie, Universit´ e Paris-Descartes, APHP, INSERM U. 567, Paris, 3 SuperSonic Imagine, Aix en Provence, 4 H´ epatologie, APHP, INSERM U. 567, Paris, France E-mail: vincent.mallet@cch.aphp.fr Background: Supersonic Shear Imaging (SSI) is a real-time ultrasound imaging system designed to quantitatively assess the elasticity in a whole organ. The technique is based on the radiation force induced by a conventional ultrasonic probe to generate a plane shear wave deep into tissues. The shear wave propagation throughout the medium is caught with an ultrafast ultrasound scanner (up to 5000 frames/s). Global elasticity (E) is derived from the shear wave velocity (Vs) estimation (E =3øVs 2 , where ø is the density). Aims: To assess the diagnostic accuracy of SSI with a liver-dedicated curved ultrasonic probe (ATL C4–2, 2.5 MHz, 128 elements) to delineate liver fibrosis in chronic liver disease (CLD). Methods: We blindly computed quantitative maps of liver elasticity in 104 patients with CLD. Hepatic fibrosis stage (F[0–4] with 4 representing cirrhosis) was determined retrospectively on the basis of histology, on a diagnosis algorithm based on three non-invasive markers performed the same day (FIB-4, APRI, FORNS), and on clinical history. The performance of SSI was assessed with one-way analysis of variance (Anova) and ROC curve analysis. Sensitivity, specificity, likelihood ratios, positive and negative predictive values were computed for the stiffness value at the maximum total sensitivity and specificity on the ROC curve. Results: B-mode images of 120×75 mm 2 and corresponding elasticity maps were obtained (Figure) with a good reproducibility and accuracy, on a large frequency bandwidth (60–600 Hz). The procedure resulted an excellent correlation between the values obtained with SSI and the fibrosis stages (P ≈ 10 −16 ). Sensitivity and Specificity at 95% are respectively 0.72 and 0.86 for F ≥ 2, 0.68 and 0.82 for F ≥ 3 and 0.90 and 0.91 for F = 4. Fibrosis heterogeneity was also obtained with an excellent differentiation between each fibrosis stages (P ≈ 10 −13 ): advanced stages of fibrosis correspond to high elasticity heterogeneities. Conclusions: SSI provides a fast and reliable map of liver elasticity and allows to assess on a large frequency bandwidth and a large area the elastic properties of the tissues. The technique is highly accurate to decipher fibrosis stages in chronic liver disease, including intermediate levels of fibrosis. 407 PROSPECTIVE RISK ASSESSMENT FOR HEPATOCELLULAR CARCINOMA RECURRENCE BY TRANSIENT ELASTOGRAPHY AFTER CURATIVE RADIOFREQUENCY ABLATION R. Masuzaki 1 , R. Tateishi 1 , S. Shiina 1 , H. Yoshida 1 , H. Nakagawa 1 , T. Arano 1 , K. Uchino 1 , K. Enooku 1 , E. Goto 1 , Y. Kondo 1 , T. Goto 1 , Y. Sugioka 2 , H. Ikeda 2 , M. Omata 1 , K. Koike 1 . 1 The University of Tokyo, 2 The University of Tokyo Hospital, Tokyo, Japan E-mail: ryota-m@umin.ac.jp Background and Aims: Liver fibrosis stage is an important indicator not only for hepatocellular carcinoma (HCC) development but also for its recurrence. Liver stiffness measurement (LSM) by transient elastography well correlates with histological fibrosis stage. Besides its noninvasiveness, LSM has wide dynamic range even within cirrhosis. The aim of this study was to elucidate the predictability S166 Journal of Hepatology 2010 vol. 52 | S59–S182