The efficiency of acoustic radiation force impulse imaging for the staging of liver fibrosis: a meta-analysis.

OBJECTIVES: Acoustic radiation force impulse (ARFI) imaging is an ultrasound-based elastography method that is integrated into a conventional ultrasound machine. A meta-analysis based on original and abstract publications was performed to evaluate the overall performance of ARFI for the diagnosis of liver fibrosis. METHODS: Literature databases and conference abstracts were searched from 2007 up to February 2012. A random effects meta-analysis of the area under the receiver operating characteristic (ROC) curve (AUROC) and the diagnostic odds ratio (DOR) was performed as well as summary ROC curve techniques. Quality analyses were conducted to assess sources of heterogeneity. RESULTS: The systematic literature search revealed 36 studies, with 3,951 patients overall. The mean diagnostic accuracy of ARFI expressed as the AUROC was 0.84 (DOR, 11.54) for the diagnosis of significant fibrosis (F ≥ 2), 0.89 (DOR, 33.54) for the diagnosis of severe fibrosis (F ≥ 3) and 0.91 (DOR, 45.35) for the diagnosis of liver cirrhosis (F = 4). Subgroup analyses showed sources of heterogeneity between the different underlying liver diseases for F ≥ 3 and F = 4. The mean body mass index had a significant influence for F ≥ 2. CONCLUSIONS: The meta-analysis revealed good diagnostic accuracy of the ARFI imaging for the staging of F ≥ 2 and F ≥ 3, and excellent diagnostic accuracy for F = 4. KEY POINTS: • Acoustic radiation force impulse (ARFI) imaging adds important information over conventional ultrasound. • ARFI imaging provides good diagnostic performance for assessing significant/severe hepatic fibrosis. • ARFI imaging shows excellent diagnostic accuracy and odds ratio for cirrhosis staging. • Body mass index significantly influences the assessment of significant fibrosis.

Aprotinin may increase mortality in low and intermediate risk but not in high risk cardiac surgical patients compared to tranexamic acid and ε-aminocaproic acid -- a meta-analysis of randomised and observational trials of over 30.000 patients.

BACKGROUND: To compare the effect of aprotinin with the effect of lysine analogues (tranexamic acid and ε-aminocaproic acid) on early mortality in three subgroups of patients: low, intermediate and high risk of cardiac surgery. METHODS AND FINDINGS: We performed a meta-analysis of randomised controlled trials and observational with the following data sources: Medline, Cochrane Library, and reference lists of identified articles. The primary outcome measure was early (in-hospital/30-day) mortality. The secondary outcome measures were any transfusion of packed red blood cells within 24 hours after surgery, any re-operation for bleeding or massive bleeding, and acute renal dysfunction or failure within the selected cited publications, respectively. Out of 328 search results, 31 studies (15 trials and 16 observational studies) included 33,501 patients. Early mortality was significantly increased after aprotinin vs. lysine analogues with a pooled risk ratio (95% CI) of 1.58 (1.13-2.21), p<0.001 in the low (n = 14,297) and in the intermediate risk subgroup (1.42 (1.09-1.84), p<0.001; n = 14,427), respectively. Contrarily, in the subgroup of high risk patients (n = 4,777), the risk for mortality did not differ significantly between aprotinin and lysine analogues (1.03 (0.67-1.58), p = 0.90). CONCLUSION: Aprotinin may be associated with an increased risk of mortality in low and intermediate risk cardiac surgery, but presumably may has no effect on early mortality in a subgroup of high risk cardiac surgery compared to lysine analogues. Thus, decisions to re-license aprotinin in lower risk patients should critically be debated. In contrast, aprotinin might probably be beneficial in high risk cardiac surgery as it reduces risk of transfusion and bleeding complications.

Contrast-Enhanced Ultrasound for the differentiation of benign and malignant focal liver lesions: a meta-analysis.

BACKGROUND: International guidelines of Ultrasound recommend the performance of contrast-enhanced ultrasound (CEUS) as the first method of choice after conventional ultrasound for the diagnostic work-up of focal liver lesions. However, these recommendations are based on the results of multiple single studies and only few large multicentre studies. AIMS: The rationale of the present systematic review and meta-analysis was to assess the overall sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions. METHODS: Literature databases were searched up to March 2012. Inclusion criteria were evaluation of CEUS, assessment of sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions. The meta-analysis was performed using the random-effects model based on the DerSimonian Laird method. Quality analyses were carried out to assess sources of heterogeneity. RESULTS: A total of 45 studies with 8147 focal liver lesions were included in the analysis. Overall sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions was 93% (95%-CI: 91-95%) and 90% (95%-CI: 88-92%) respectively. Significant heterogeneity was found between studies. However, subanalysis revealed no significant difference when evaluating studies using histology for all liver lesions, when comparing high-quality and low-quality studies, and blinded vs non-blinded studies. CONCLUSION: The results of this meta-analysis support the international recommendations on CEUS for the diagnostic work-up of focal liver lesions selecting patients who need further diagnostics.