Focal nodular hyperplasia: new findings at Doppler ultrasonography.

OBJECTIVE: The aim of our study was to explore the features of focal nodular hyperplasia (FNH) at Doppler ultrasonography, analyzing specifically the presence of intratumoral venous flow in patients with an established diagnosis of FNH. Previous studies showed that using a venous Doppler spectrum, intratumoral vessels are often depicted in hepatocellular adenoma (HCA) but less frequently in FNH. PATIENTS AND METHODS: Forty-five FNHs from thirty-three consecutive patients (26 female, 7 male; mean±SD age: 40±13) underwent color Doppler ultrasonography and spectral analysis according to a standardized protocol. FNH diagnosis was established by the presence of typical behavior at contrast-enhanced ultrasound (CEUS) associated with another imaging technique (contrast-enhanced computed tomography [ceCT] or contrast-enhanced magnetic resonance [ceMR]). A biopsy was performed when imaging was inconclusive. All data concerning Doppler analysis were reviewed by two more operators, blinded to the final diagnosis, and the interobserver agreement for the presence of venous Doppler signal was determined by Cohen's Kappa. RESULTS: Of the 33 patients, 24 had a single solitary focus, and 9 had multiple foci. Lesion diameter ranged between 1.2 and 8.9 cm (mean ± SD 3.2±1.6 cm). The central feeding artery with the typical arterial spectrum was detected in all 45 lesions, whereas the spoke-wheel sign was observed in 18 cases (40%). A venous Doppler signal was detected in 35 FNHs (77.8%), and in 60% of them, it was identified in the center of the lesion. CONCLUSIONS: Venous Doppler signal located in the center of the lesion suspected to be a hypervascular benign lesion cannot be considered a typical HCA feature since it has been detected in a high percentage of FNH cases.

Assessment of liver fibrosis in transplant recipients with recurrent HCV infection: usefulness of transient elastography.

BACKGROUND: Progression of recurrent hepatitis C is accelerated in liver transplant recipients, leading to special need of non-invasive validated methods to estimate liver fibrosis. AIM: To assess the efficacy of liver stiffness measurement by transient elastography (Fibroscan) and serum parameters in predicting fibrosis stage in HCV-infected transplant recipients. METHODS: The correlation between liver fibrosis, assessed at liver histology on bioptic specimens obtained for clinical indications, and stiffness or clinico-serological indexes (Benlloch, APRI, Forns, Fibrotest and Doppler resistance index), was investigated in transplant recipients with recurrence of HCV chronic hepatitis. A total of 56 patients (of which 36 with all clinico-serological indexes), presenting with the following METAVIR fibrosis stage F1=38, F2=9, F3=8, F4=1, were enrolled in the study population. Differences between fibrosis stages were calculated by non-parametric analysis. The best cut-off for identifying significant fibrosis (F2-F4) was assessed by ROC curve analysis. RESULTS: Stiffness (median and range) was 7.7 KPa (range 4.2-13.9) in F1 and 17.0KPa (range 6.8-36.3) in >or=F2 (p<0.001). A stiffness cut-off of 10.1 KPa revealed 94% Sensitivity, 89% Specificity, 81% PPV and 94% NPV in differentiating F1 from F2-F4. The area under the receiver operator curve in the assessment of fibrosis was significantly higher for Liver stiffness (AUROC 0.943) than for any of the other non-invasive indexes (AUROCs ranging 0.591-0.815). CONCLUSIONS: Transient elastography of the liver provides good accuracy in identifying patients with significant fibrosis and performs better than non-invasive indexes based on clinico-serological parameters in transplant recipients.

Knowledge of the bio-effects of ultrasound among physicians performing clinical ultrasonography: Results of a survey conducted by the Italian Society for Ultrasound in Medicine and Biology (SIUMB).

INTRODUCTION: Safety issues should always be kept in mind when using diagnostic ultrasound, which is associated with potentially hazardous bio-effects, especially with the introduction of new technologies. AIM: To assess the level of awareness and knowledge of safety issues related to the clinical use of ultrasound among physician-members of the Italian National Society for Ultrasound. MATERIALS AND METHODS: A questionnaire with 11 multiple-choice questions was sent to members of the Italian Society for Ultrasound in Medicine and Biology. The answers were forwarded from the Society's Secretariat to the investigators, who statistically analyzed the data. RESULTS: The mean age of the 105 respondents was 44 years. The most frequent kind of ultrasound examinations (in addition to conventional B-mode) were: Doppler (74%), contrast-enhanced US (43%), and pediatric studies (43%). Only 50-60% of the responders knew the correct definitions of the terms thermal index and mechanical index. Almost all respondents understood the bio-effects reflected by the thermal index, but only a minority knew the most likely organ target of bio-effects related to the mechanical index and what do indicate the units in which the thermal index is expressed. The majority knew that fetuses are at higher risk of damage. Few respondents were able to identify the correct safety statements included in the recommendations of the International Ultrasound Societies. CONCLUSION: In conclusion, the present findings indicate that greater efforts of National Ultrasound Societies are warranted in disseminating knowledge of the bio-effects of diagnostic ultrasound modalities among operators.