Comparison of LI-RADS with other non-invasive liver MRI criteria and radiological opinion for diagnosing hepatocellular carcinoma in cirrhotic livers using gadoxetic acid with histopathological explant correlation.

AIM: To establish the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) and compare its performance to that of international criteria from European Assofor the Study of the Liver (EASL), Japan Society of Hepatology (JSH), Asian Pacific Association for the Study of the Liver (APASL), and Organ Procurement and Transplantation Network (OPTN), and to the reporting radiologist's overall opinion regarding the probability of a nodule being a HCC by correlating with a histological diagnosis from whole liver explants. MATERIALS AND METHODS: The present single-centre, retrospective review selected participants based on the following criteria: adults (≥18 years) listed for liver transplantation in 2014/2015, with liver cirrhosis at the time of magnetic resonance imaging (MRI) with hepatocyte specific contrast agent, and at least one liver lesion ≥10 mm on MRI with histology from subsequent liver explant for comparison. Each lesion was assessed against international criteria and given a "radiologist opinion" score of 1-5 (1 = definitely benign, 5 = definitely HCC). RESULTS: Total 268 patient records were reviewed, with 105 eligible lesions identified from 47 patients. Median lesion size was 15.5 mm (range 10-68 mm). Sensitivity (%), specificity (%), and positive predictive value (PPV; %) for LI-RADS LR5 was 45, 89, and 89, for LI-RADS LR4+5 + TIV was 61, 80, and 86, for EASL was 44, 86 and 86, for JSH/APASL was 64, 81, and 87, for OPTN was 36, 90, and 88, and for "radiologist impression" of probably or definitely HCC was 79, 79, and 88 respectively. CONCLUSIONS: MRI has moderate sensitivity and good specificity for the diagnosis of HCC with considerable variation depending on criteria used. OPTN criteria have the best specificity, but low sensitivity. "Radiologist opinion" gives highest overall accuracy with increases in sensitivity and reduction in specificity when compared to the imaging criteria.

Mechanisms involved in the activation of ischemically sensitive, afferent renal nerve mediated reflex increases in hind-limb vascular resistance in the anesthetized rabbit.

Acute occlusion of the renal circulation in the anesthetized rabbit results in a neurally mediated, reflex increase in hind-limb vascular resistance, which is flow rather than pressure dependent. This suggests that the activating stimulus could be ischemia. In the present study vascularly isolated kidneys were perfused with hypoxemic or hypercapnic blood, and the hind-limb vascular response was measured. Renal perfusion with hypoxemic blood resulted in an increase in femoral perfusion pressure (FPP), which was negatively correlated with the oxygen tension of the blood. At a PO2 of 36.4 +/- 0.9 mmHg (1 mmHg = 133.3 Pa), FPP rose by 34.4 +/- 5.7 mmHg. Renal denervation abolished this effect. Renal perfusion with hypercapnic blood had no effect on FPP. Prostaglandin E2, bradykinin, and adenosine are released during renal ischemia and have been implicated in the mediation of afferent renal nerve activity; intrarenal administration (prostaglandin E2, 10 micrograms; bradykinin, 5 micrograms; adenosine, 20 micrograms; as a 1-mL bolus) during renal perfusion with normoxemic blood elicited increases in FPP of 32.4 +/- 13.2, 19.2 +/- 3.7, and 55.6 +/- 17.8 mmHg, respectively. Intrarenal indomethacin, aprotonin, and aminophylline all inhibited the increase in FPP observed during renal perfusion with hypoxemic blood. These data indicate that renal hypoxemia stimulates an afferent renal nerve mediated increase in FPP and suggest that prostaglandin E2, bradykinin, and adenosine may all be involved in the activation of ischemically sensitive R1 chemoreceptors.