BACKGROUND/AIMSTo compare the sensitivity of helical CT to that of helical CT arterial portography in the detection of hepatic primary or secondary malignancies, in 20 patients who subsequently underwent surgery to confirm findings.METHODOLOGYTwenty patients with suspected primary hepatic or secondary malignancies who all underwent helical CT and helical CT arterial portography preoperatively were prospectively evaluated. All the images were reviewed by two radiologists. The results were subsequently correlated with surgical and pathological findings. The sensitivity and the positive predictive values for lesion detection were determined for each modality.RESULTSThere were 39 pathologically confirmed hepatic malignant lesions. The overall sensitivity and positive predictive value of helical CT arterial portography were 87.1% and 82.5%, respectively, while of helical CT were 84.6% and 94.2%, respectively.CONCLUSIONSHelical CT arterial portography and helical CT of the liver were approximately equivalent for lesion detection in patients who were evaluated preoperatively for resection of liver malignancies. The lower cost and non-invasive nature of helical CT suggest that it should be the preferred modality.

Background/Aims: A prospective study was performed to compare the sensitivities of computed tomography, magnetic resonance imaging and CTAP (CT during arterial portography) in the detection of focal malignant hepatic lesions.Methodology: Twenty-eight (28) patients with primary and secondary hepatic malignant tumors were evaluated. All of these patients underwent hepatic resection and a lesion-to-lesion imaging-pathological analysis was performed.Results: The overall sensitivities were 53% for CT, 66% for MRI sequences and 88% for CTAP. For lesions smaller than 1cm the sensitivities were 6% for CT, 17% for MRI and 72% for CTAP. The combination of CTAP and MRI yielded an overall detection rate of 93%. The difference between the sensitivity of CTAP and that of the other two imaging techniques was statistically significant (P<0.04) according to the McNemar test. CTAP demonstrated four false-positive lesions, two of which were correctly characterized by MRI and one by CT. In 6 patients (21.4%) the surgical plan was modified after CTAP.Conclusions: We conclude that, CTAP has the highest sensitivity and should be part of the preoperative examination. In some instances, the addition of MR imaging must be considered a helpful adjuvant. Both techniques should be considered complementary in the preoperative diagnostic algorithm.

S-35 (Saturation of haemoglobin at PO2 = 35mmHg) is a new concept in monitoring systemic oxygenation that includes the effect of changes in oxyhaemoglobin dissociation curve (ODC) on oxygen delivery. This study was designed to evaluate any possible alterations in oxyhaemoglobin dissociation curve and in S-35 of critical intrabdominal organs (small bowel, liver and kidney) in an experimental liver transplantation model. Ten pigs of mean body weight of 25-30kg underwent OLTx under homogenous anaesthesiological and technical procedures. Five of them were healthy (Group B) while the other five (Group C) were in fulminant hepatic failure (FHF) which had been surgically induced. Five healthy pigs underwent general anaesthesia and were used as a control group (Group A). Venous blood gas analysis was performed in superior mesenteric, hepatic and renal veins at well-defined timepoints during the course of OLTx. Regarding Group C, there has been a statistically significant decrease of S-35 after reperfusion in small bowel, in comparison to base-line values (implying a rightwards shift of ODC). This may be attributed to an attempt to meet increased metabolic needs of an organ which seems to be mostly involved. In opposite, the ODC seems to remain unaffected in both liver and kidney, probably due to temporarily limited metabolic activity.

The increasing incidence of fulminant-viral and toxic-hepatic failure (F.H.F.) and the severe shortage of cadaveric liver donors in Greece have stressed the need for the development of liver support systems, which will be used as temporary metabolic support of F.H.F. patients until the host liver regenerates or a suitable graft is provided. The aim of the present study was to evaluate an extracorporeal liver support system (E.L.S.SY.) based on an isolated pig liver graft as a means of temporary metabolic support in a surgically induced acute liver failure (ALF) model in pigs. E.L.S.SY. application for a 6-hour period of observation showed worsening of haemodynamic condition probably due to big extracorporeal volume or circulating toxins or mediators delivered from the ischaemic hepatic tissue. However, there is evidence of: metabolic support provided by the E.L.S.SY. which could be more obvious if treatment had been instituted at an earlier stage or porcine hepatocytes substitute the isolated graft (currently under investigation).