K Kusaka

Objective evaluation of Liver consistency to estimate hepatic fibrosis and functional reserve for hepatectomy

BACKGROUND The empiric evaluation of liver consistency is currently used to plan the surgical strategy. The aim of this study was to verify the feasibility of the objective measurement of liver consistency and to check its correlation with liver fibrosis and liver functional reserve. STUDY DESIGN Fifty-two consecutive patients who underwent hepatic resections in our department were enrolled. The indications for liver resection were hepatocellular carcinoma in 36 patients, metastatic liver tumors in 12 patients, and other conditions in 4 patients. Liver consistency was measured with a new tactile sensor. A fibrosis index was calculated as an expression of the percentage of fibrotic tissue. Liver consistency was compared with the degree of liver fibrosis observed in histologic specimens (fibrosis index) and with liver function parameters. RESULTS Liver stiffness showed a significant positive correlation with fibrosis index (r = 0.887, p < 0.0001). Liver stiffness also showed significant positive correlation with the indocyanine green test (r = 0.631, p < 0.0001) by a univariate analysis. The indocyanine green test and platelet count were independently and significantly associated with liver stiffness by a multiple regression analysis. In five patients, the liver stiffness values measured intraoperatively differed markedly from those expected from the indocyanine green test values. In these patients, the operative procedures were finally selected based on the liver stiffness measured with the tactile sensor and good clinical outcomes were obtained. CONCLUSIONS These results show for the first time that liver stiffness can be clinically assessed quantitatively by means of the tactile sensor. The tactile sensor adequately estimates liver stiffness and this estimation is well correlated with liver fibrosis and functional reserve. Liver consistency determined objectively in this manner may be useful for optimizing surgical decision making.

Indocyanine green‐fluorescent imaging of hepatocellular carcinoma during laparoscopic hepatectomy: An initial experience

Introduction: Laparoscopic hepatectomy has disadvantages in intraoperative diagnosis, because it offers limited visualization and palpability of the liver surface. Recently, we developed a novel fluorescent imaging technique using indocyanine green (ICG), which would enable identification of liver cancers during open hepatectomy. However, this technique has not yet been applied to laparoscopic hepatectomy.

Expression of Transforming Growth Factor-α and -β in Hepatic Lobes After Hemihepatic Portal Vein Embolization

Hemihepatic portal vein embolization (PVE) concomitantly induces atrophy in embolized and compensatory hypertrophy in nonembolized hepatic lobes. The aim of the present study was to evaluate the involvement of growth stimulatory and inhibitory factors in these hepatic lobes after PVE. Liver specimens from the embolized and nonembolized lobes of ten patients who underwent hepatectomy (8–22 days) after undergoing PVE were obtained. Proliferation and apoptosis were examined immunohistochemically using Ki-67 and the Tdt-mediated dUTP-biotin nick end-labeling method. The expression of transforming growth factor-α (TGF-α) and transforming growth factor-β (TGF-β) was also examined by immunohistochemical staining. PVE induced hepatocyte apoptosis in the embolized lobe and hepatocyte proliferation in the nonembolized lobe. TGF-α expression in the hepatocytes of the nonembolized lobe was markedly increased, whereas TGF-α was also overexpressed, albeit moderately, in the embolized lobe. In contrast, TGF-β expression in the hepatocytes of the embolized lobe was significantly increased, and TGF-β expression was also increased, although to a lesser extent, in the nonembolized lobe. The degree of volume changes of the nonembolized lobe and the embolized lobe after PVE was statistically correlated with the ratios of TGF-α and TGF-β expression in these lobes (r = 0.886, P < .0001). In conclusion, these findings indicate that TGF-α and TGF-β expression (assessed by immunohistochemical staining) increase in relation to hepatocyte proliferation and apoptosis, respectively, after PVE in humans and the balance of the two factors may contribute to hepatic atrophy and hypertrophy concomitantly observed in this model.

Immunosuppressive effect of chenodeoxycholic acid on natural killer cell activity in patients with biliary atresia and hepatitis C virus-related liver cirrhosis.

Patients with severe liver diseases, such as liver cirrhosis and biliary atresia, have low natural killer (NK) cell activity. The relations between NK activity and measures of liver function, including serum levels of total bilirubin, total bile acids, bile acid components, aspartate aminotransferase, and alanine aminotransferase, and platelet count were examined in patients with biliary atresia (6 boys and 6 girls; mean age, 4.8 ± 5.7 years) and patients with liver cirrhosis due to hepatitis C virus infection (10 men and 2 women; mean age, 54.3 ± 13.8 years). Univariate analysis showed that platelet count was positively correlated with NK activity in patients with biliary atresia (r = 0.611, P < 0.05). Serum levels of free chenodeoxycholic acid were negatively correlated with NK activity both in patients with biliary atresia (r = −0.647, P < 0.05) and in patients with hepatitis C virus-related liver cirrhosis (r = −0.876, P < 0.01). None of the other free bile acids or conjugated bile acids or other indicators of liver function were correlated with NK activity. Multiple stepwise regression analysis showed that only levels of free chenodeoxycholic acid were independently correlated with NK activity. All patients with biliary atresia underwent liver transplantation from living related donors. NK activity had increased significantly two months after transplantation (from 24.1 ± 20.2% to 49.2 ± 12.5%, P < 0.01). In contrast, levels of free chenodeoxycholic acid in transplant recipients had decreased significantly two months after transplantation (from 1.22 ± 1.16 to 0.26 ± 0.21 μmol/l, P < 0.05). In conclusion, in patients with biliary atresia or liver cirrhosis, NK activity in peripheral blood decreases, mostly because of free chenodeoxycholic acid.

Resection of a methicillin-resistant Staphylococcus aureus liver abscess in a patient with Crohn's disease under infliximab treatment: a case report

IntroductionA liver abscess in Crohn’s disease is a rare but important entity that is associated with a poor prognosis and high mortality when treatment is delayed. We report a case of successful liver segmentectomy for a methicillin-resistant Staphylococcus aureus liver abscess in a patient with Crohn’s disease under infliximab treatment.Case presentationA 31-year-old Japanese man, who had been treated with infliximab infusions for Crohn’s disease, was referred to our hospital presenting with an abrupt onset of high fever and an elevated white blood cell count and serum C-reactive protein level. Computed tomography revealed a liver abscess occupying segment 8. The limited effect of percutaneous transhepatic abscess drainage and antibiotics led us to perform radical resection of the abscess. The patient recovered quickly after surgery and the postoperative course was uneventful.ConclusionThe present case suggests that surgical removal of an abscess should be considered for patients under immunosuppression or refractory to conventional treatment.

Scientific Basis and Clinical Application of ICG Fluorescence Imaging: Hepatobiliary Cancer~!2009-10-02~!2009-12-23~!2010-05-26~!

Despite recent advances in imaging modalities, the intraoperative diagnosis of small liver cancers remains unsatisfactory. Although fluorescent imaging using indocyanine green (ICG) has just been applied to hepatobiliary surgeries, this technique has the potential to delineate small liver cancers during surgery, through allowing visualization of the disordered biliary excretion of ICG in the hepatocellular carcinoma (HCC) tissues and non-cancerous liver tissues surrounding metastasis of colorectal cancer (CRC). In this technique, ICG is administered intravenously for routine liver function testing before surgery, at the dose of 0.5 mg per kg body weight. The liver surfaces prior to resection, and the cut surfaces of the resected specimen, are examined by the fluorescent imaging system. In our previous series, ICGfluorescent imaging prior to resection delineated more than 90% of liver cancers that were located within 10 mm of the liver surface. On examination of the cut surfaces of the resected specimens, this technique identified all of the microscopically confirmed HCCs and metastases of CRC. Furthermore, ICG-fluorescent imaging was useful to detect small HCCs that were not evident grossly unless visualized by this technique, as reported by Gotoh et al. These results suggest that ICG-fluorescent imaging enables the highly sensitive identification of small liver cancers in real time during liver resection and the subsequent macroscopic examination, enhancing the accuracy of surgery and operative cancer

Measurement of liver volume and hepatic functional reserve as a guide to decision-making in resectional surgery for hepatic tumors

The respective volumes of hepatic tumors and nontumorous parenchyma of 50 patients requiring hepatectomy of more than one segment of Healey for tumor removal were measured using computed tomography (Vol-CT). The volume estimated by Vol-CT was found to correlate with the real weight resected (P < .0001) with a mean absolute error of 64.9 mL. The ratio of the nontumorous parenchymal volume of the resected liver to that of the whole liver (R2) in 15 patients who underwent right or extended right hepatic lobectomy was 43% +/- 15%. Eight of 15 patients with R2s < 60% underwent the procedures without right portal vein embolization (PE). The other seven with R2s exceeding 60% or an indocyanine green retention rate after 15 minutes (ICG15) of 10% to 20% underwent PE: in six of seven, the nontumorous parenchyma of the right hepatic lobe became atrophic and in all seven, the volume of the remaining left hepatic lobe increased with a decrease in the mean R2 from 62% +/- 14% to 55% +/- 8% (P = .0006). In the remaining 35 who underwent other hepatectomy procedures, R2s also remained <60%. Overall, at surgery, in 27 with normal liver function (ICG15 < 10%), R2s exceeded 60% in one, remained at 50% to 60% in five, and <50% in 21, whereas 23 patients except for one with an ICG15 exceeding 10%, had R2s of <50%. The postoperative serum total bilirubin levels in 84% of the patients remained within the normal range and there was no surgery-related mortality. In conclusion, 1) Vol-CT can accurately assess the extent of liver resection, 2) individuals with normal liver function can undergo resection of up to 60% of the nontumorous parenchyma without the need for PE, and 3) PE can be used to reduce the size of the resected tissue and increase the volume of the remnant liver to approximate the target limits in individuals with large tumors or minimally abnormal liver function.