Hepatic Arterial Perfusion Index Research Articles

Kinetic 18F-FDG PET/CT imaging of hepatocellular carcinoma: a dual input four-compartment model.

The endoplasmic reticulum plays an important role in glucose metabolism and has not been explored in the kinetic estimation of hepatocellular carcinoma (HCC) via 18F-fluoro-2-deoxy-D-glucose PET/CT. A dual-input four-compartment (4C) model, regarding endoplasmic reticulum was preliminarily used for kinetic estimation to differentiate 28 tumours from background liver tissue from 24 patients with HCC. Moreover, parameter images of the 4C model were generated from one patient with negative findings on conventional metabolic PET/CT. Compared to the dual-input three-compartment (3C) model, the 4C model has better fitting quality, a close transport rate constant (K1) and a dephosphorylation rate constant (k6/k4), and a different removal rate constant (k2) and phosphorylation rate constant (k3) in HCC and background liver tissue. The K1, k2, k3, and hepatic arterial perfusion index (HPI) from the 4C model and k3, HPI, and volume fraction of blood (Vb) from the 3C model were significantly different between HCC and background liver tissues (all P < 0.05). Meanwhile, the 4C model yielded additional kinetic parameters for differentiating HCC. The diagnostic performance of the top ten genes from the most to least common was HPI(4C), Vb(3C), HPI(3C), SUVmax, k5(4C), k3(3C), k2(4C), v(4C), K1(4C) and Vb(4C). Moreover, a patient who showed negative findings on conventional metabolic PET/CT had positive parameter images in the 4C model. The 4C model with the endoplasmic reticulum performed better than the 3C model and produced additional useful parameters in kinetic estimation for differentiating HCC from background liver tissue.

Dynamic chaotic gravitational search algorithm-based kinetic parameter estimation of hepatocellular carcinoma on 18F-FDG PET/CT

BackgroundKinetic parameters estimated with dynamic 18F-FDG PET/CT can help to characterize hepatocellular carcinoma (HCC). We aim to evaluate the feasibility of the gravitational search algorithm (GSA) for kinetic parameter estimation and to propose a dynamic chaotic gravitational search algorithm (DCGSA) to enhance parameter estimation.MethodsFive-minute dynamic PET/CT data of 20 HCCs were prospectively enrolled, and the kinetic parameters k1 ~ k4 and the hepatic arterial perfusion index (HPI) were estimated with a dual-input three-compartment model based on nonlinear least squares (NLLS), GSA and DCGSA.ResultsThe results showed that there were significant differences between the HCCs and background liver tissues for k1, k4 and the HPI of NLLS; k1, k3, k4 and the HPI of GSA; and k1, k2, k3, k4 and the HPI of DCGSA. DCGSA had a higher diagnostic performance for k3 than NLLS and GSA.ConclusionsGSA enables accurate estimation of the kinetic parameters of dynamic PET/CT in the diagnosis of HCC, and DCGSA can enhance the diagnostic performance.

CT hepatic arterial perfusion index does not allow stratification of the degree of esophageal varices and bleeding risk in cirrhotic patients in Child\u2013Pugh classes A and B

PurposeTo evaluate if the hepatic arterial perfusion index (HPI) in liver parenchyma of cirrhotic patients can serve as a surrogate parameter for stratifying the degree of esophageal varices and related bleeding risks.MethodsCT image data of sixty-six patients (59 men; mean age 68 years ± 10 years) with liver cirrhosis (Child–Pugh class A (35/66, 53%), B (25/66, 38%), and C (6/66, 9%) who underwent perfusion CT (PCT) for hepatocellular carcinoma (HCC) screening between April 2010 and January 2019 were retrospectively identified. HPI, a parameter calculated by a commercially available CT liver perfusion analysis software that is based on the double maximum slope model, using time attenuation curve to determine perfusion, was correlated with the degree of esophageal varices diagnosed at endoscopy and the number of bleeding events.ResultsEta correlation coefficient for HPI/presence of esophageal varices was very weak (0.083). Spearman-Rho for HPI/grading of esophageal varices was very weak (0.037 (p = 0.804)). Kendall-Tau-b for HPI/grading of esophageal varices was very weak (0.027 (p = 0.807)). ANOVA and Bonferroni post-hoc-tests showed no significant difference of HPI between different grades of esophageal varices (F (3, 62) = 1.676, p = 0.186). Eta correlation coefficient for HPI/bleeding event was very weak (0.126).ConclusionThe stratification of the degree of esophageal varices and the related bleeding risk by correlation with the HPI as a surrogate parameter for portal venous hypertension was not possible for patients with liver cirrhosis in Child–Pugh class A and B.Graphic abstract

Feasibility of perfusion and early-uptake 18F-FDG PET/CT in primary hepatocellular carcinoma: a dual-input dual-compartment uptake model.

PET enables a concurrent evaluation of perfusion status and metabolic activity. We aimed to evaluate the feasibility of perfusion and early-uptake 18F-FDG PET/CT in hepatocellular carcinoma (HCC) using a dual-input dual-compartment uptake model. Data from 5min dynamic PET/CT and conventional PET/CT scans were retrospectively collected from 17 pathologically diagnosed HCCs. Parameters such as hepatic arterial blood flow (Fa), portal vein blood flow (Fv), total blood flow (F), hepatic arterial perfusion index (HPI), portal vein perfusion index (PPI), blood volume (BV), extracellular mean transit time (MTT) and intracellular uptake rate (Ki) were calculated. Fa, HPI, MTT and Ki images were generated and used to identify HCC. Compared with the surrounding liver tissue, HCCs showed significant increases in Fa, HPI, Ki and the maximum standard uptake value (SUVmax) (all P < 0.001) and significant reductions in Fv (P < 0.05) and PPI (P < 0.001). F, BV and MTT (all P > 0.05) did not differ significantly between HCCs and the surrounding liver tissue. Perfusion and early-uptake PET/CT increased the positivity rate of HCCs from 52.9% with conventional PET/CT alone to 88.2% with the combined method (P < 0.05). Perfusion and early-uptake PET/CT are feasible for diagnosing HCC and provide added functional information to enhance diagnostic performance.

Comparison of MR-PWI quantitative and semi-quantitative parameters for the evaluation of liver fibrosis

BackgroundTo evaluate different stages of liver fibrosis in cynomolgus monkeys by comparing magnetic resonance-perfusion weighted imaging (MR-PWI) quantitative and semi-quantitative parameters, and confirm the best detection indicators for diagnosis of liver fibrosis.MethodsA liver fibrosis model of different stages (S0–S4) was established in cynomolgus monkeys. The changes in MR-PWI quantitative and semi-quantitative parameters with the progression of liver fibrosis were investigated.ResultsMR-PWI quantitative parameters gradually decreased with the progression of liver fibrosis. Hepatic arterial perfusion index (HPI) was found to increase with the progression of liver fibrosis and significant differences of HPI between each group were observed. There was a highly positive correlation between HPI and the stages of liver fibrosis. Receiver operating characteristic (ROC) curve analysis showed that HPI had the highest efficacy of the MR-PWI quantitative parameters for the diagnosis of liver fibrosis. The MR-PW semi-quantitative parameters gradually reduced with the progression of liver fibrosis, and the differences were statistically significant between stages S3–S4 and S0–S2. Time to peak (TPP) gradually extended and showed a positive correlation with the stages of liver fibrosis. TTP had the highest efficacy of the semi-quantitative parameters for diagnosis of liver fibrosis.ConclusionsBoth the MR-PWI quantitative and semi-quantitative parameters of the liver fibrosis model in cynomolgus monkeys varied at different stages of liver fibrosis, and HPI and TTP were the best detection indices for quantitative and semi-quantitative evaluation of liver fibrosis, respectively.

[Quantitative evaluation of early stage blood flow change status after radiofrequency ablation based on multi-slice spiral CT whole-liver perfusion imaging on small hepatocellular carcinoma].

Objective: To investigate the blood flow change status in early stage tumor-related areas of hepatocellular carcinoma and its clinical significance after radiofrequency ablation using multi-slice spiral CT whole-liver perfusion imaging technology. Methods: 21 cases of primary liver cancer that underwent CT-guided radiofrequency ablation were included. CT perfusion scans were divided into four groups according to the time points of CT scans (before surgery, immediately after surgery and 1 and 3 month after surgery), and then blood perfusion parameters of the corresponding areas of the tumor were measured. Statistical analysis was performed using two independent samples of non-parametric Wilcoxon rank-sum test. The differences of blood perfusion parameters between tumor or ablation lesion and background liver parenchyma, paratumor tissue or inflammatory response zone were compared before, immediately and 1 and 3 months after surgery, respectively. Results: (1) The hepatic arterial perfusion (HAP) and hepatic arterial perfusion index (HPI) of cancerous liver tumors and background liver parenchyma was significantly increased (P < 0.01). The total liver perfusion (TLP) was higher than the background liver parenchyma (P = 0.01 < 0.05). The time to peak (TTP) was significantly lower than background liver parenchyma (P < 0.01); (2) The perfusion parameters of HAP, PVP and TLP were lower than the background liver parenchyma in the complete ablation lesions immediately after radiofrequency ablation and 1 and 3 months after surgery, and the difference was statistically significant (P < 0.05); (3) The inflammatory response zone of ablation lesions of HAP, HPI, and TLP were gradually decreased with the extended postoperative time and TTP was gradually increased, while PVP did not change significantly; (4) HAP, HPI, and TTP were compared between the tumor and the tumor inflammatory response zone immediately after surgery, and 1 and 3 months after surgery, and the difference was statistically significant (P < 0.01). However, there was no statistically significant difference between PVP and TLP (P > 0.05). Conclusion: CT whole-liver perfusion imaging can precisely evaluate the early stage blood flow change status in peritumor and tumors before and after radiofrequency ablation and then objectively evaluate tumor's blood supply and therapeutic effect on hepatocellular carcinoma.

[Diagnostic value of computed tomographic perfusion imaging of whole liver for quantitative assessment of blood flow state in liver cancer after transcatheter arterial chemoembolization].

Objective: To investigate the diagnostic value of whole liver CT perfusion imaging in the quantitative evaluation of hemodynamic changes before and after transcatheter arterial chemoembolization (TACE). Methods: Twenty-six patients with hepatocellular carcinoma underwent TACE therapies were recruited. Whole -liver computed tomographic perfusion imaging (CTPI) was performed 2~3 days before TACE and 1 month after TACE. We measured the following perfusion parameters: hepatic arterial perfusion (HAP), portal venous perfusion (PVP), total liver perfusion (TLP), hepatic arterial perfusion index (HAPI), and time-to-peak (TTP).The F-test, t-test and Rank sum test were used for statistical analysis. Results: A total of 34 HCC lesions were detected. According to the deposition of lipiodol after TACE, they were divided into a lipiodol dense group (21) and a lipiodol light group (13). The length of hepatocellular carcinoma lesions after TACE showed a decreasing trend compared with preoperative TACE. The lesions in the lipiodol dense group had smaller lesions than those in the lipiodol light group. The preoperative and postoperative longitudinal diameters were (3.12 ± 0.58) cm vs. (1.93 ± 0.79) cm, (2.98 ± 2.01) cm vs. (2.58 ± 2.00) cm, the differences were statistically significant (t = 15.1, 8.65, P < 0.05). The preoperative HAP and HPI of the lipiodol dense group were the highest, and the peritumoral within 1cm was higher than that of the surrounding liver parenchyma. The PVP, TLP, and TTP were highest in the surrounding of liver parenchyma, and 1 cm higher than the tumor area in the background. The corresponding perfusion parameters were statistically significant (P < 0.05); HAP and HPI were 1 cm higher than the surrounding liver parenchyma. After the operation, PVP, TLP and TTP were lower than the background liver parenchyma, the difference was statistically significant (P < 0.05); HAP and HPI decreased by 1 cm after the operation, and the PVP, TLP, and TTP increased. There was no significant difference after operation in the blood perfusion of background liver parenchyma (P ˃ 0.05). The HAP and HPI decreased, and the PVP and TTP increased in the lipiodol light group after operation (P < 0.05). There was no significant difference between the other two regions (P ˃ 0.05). Conclusion: There was no blood perfusion in the lipiodol deposition area after TACE. The perfusion volume of hepatic artery in the peritumoral 1 cm and lipiodol light group decreased and the portal venous perfusion increased. CTPI can quantitatively evaluate blood perfusion state, which is of great significance for the determination of treatment plans before TACE treatment to assume the postoperative therapeutic effect in liver cancer.

Comparison of microvascular perfusion evaluation among IVIM-DWI, CT perfusion imaging and histological microvessel density in rabbit liver VX2 tumors

ObjectTo explore microcirculation features with intravoxel incoherent motion (IVIM) and to compare IVIM with CT perfusion imaging (CTPI) and microvessel density (MVD). Materials and methodsHepatic CTPI and IVIM were performed in 16 rabbit liver VX2 tumor models. Hepatic arterial perfusion (HAP), hepatic arterial perfusion index (HPI), Blood flow (BF), and blood volume (BV) from CTPI were measured. Apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion fraction (f), and pseudo-diffusion coefficient (D*) from IVIM were measured. MVD was counted with CD34 stain. The microcirculation features with IVIM were compared with CTPI parameters and MVD. ResultsStrong linear correlations were found between D value (0.89±0.21×10−3mm2/s) and HAP (15.83±6.97ml/min/100mg) (r=0.755, P=0.001) and between f value (12.64±6.66%) and BV (9.74±5.04ml/100mg) (r=0.693, P=0.004). Moderate linear correlations were observed between ADC (1.07±0.32×10−3mm2/s) and HAP (r=0.538, P=0.039), respectively; and between D value and MVD (9.31±2.57 vessels at 400×magnification) (r=0.509, P=0.044). No correlations were found between D* (119.90±37.67×10−3mm2/s) and HAP, HPI (68.34±12.91%), BF (4.95±2.16ml/min/100mg), BV. ConclusionIVIM parameters can characterize microcirculation to certain extent and separate it from pure water molecular diffusion. There is fair correlation between D or ADC value and CTPI parameters or MVD, but no correlation between D* or f value and CTPI parameters or MVD except f value and BV, which is still unclear and need further clinical studies to validate.

Diagnostic value of dynamic contrast-enhanced CT with perfusion imaging in the quantitative assessment of tumor response to sorafenib in patients with advanced hepatocellular carcinoma: A feasibility study

PurposeTo investigate the feasibility of perfusion-CT (p-CT) measurements in quantitative assessment of hemodynamic changes related to sorafenib in patients with advanced hepatocellular carcinoma (HCC). Materials and methodsTwenty-two patients with advanced HCC underwent p-CT study (256-MDCT scanner) before and 2 months after sorafenib administration. Dedicated perfusion software generated a quantitative map of arterial and portal perfusion and calculated the following perfusion parameters in target liver lesion: hepatic perfusion (HP), time-to-peak (TTP), blood volume (BV), arterial perfusion (AP), and hepatic perfusion index (HPI). After the follow-up scan, patients were categorized as responders and non-responders, according to mRECIST. Perfusion values were analyzed and compared in HCC lesions and in the cirrhotic parenchyma (n=22), such as between baseline and follow-up in progressors and non-progressors. ResultsBefore treatment, all mean perfusion values were significantly higher in HCC lesions than in the cirrhotic parenchyma (HP 47.8±17.2 vs 13.3±6.3mL/s per 100g; AP 47.9±18.1 vs 12.9±10.7mL/s; p<0.001). The group that responded to sorafenib (n=17) showed a significant reduction of values in HCC target lesions after therapy (HP 29.2±23.3 vs 48.1±15.1; AP 29.4±24.6 vs 49.2±17.4; p<0.01), in comparison with the non-responder group (n=5) that demonstrated no significant variation before and after treatment of HP (46.9±25.1 vs 46.7±24.1) and AP (43.4±21.7 vs 43.5±24.6). Among the responder group, HP percentage variation (Δ) in target lesions, during treatment, showed a significantly different (p=0.04) ΔHP in the group with complete response (79%) compared to the group with partial response or stable disease (16%). Conclusionsp-CT technique can be used for HCC quantitative assessment of changes related to anti-angiogenic therapy. Identification of response predictors might help clinicians in selection of patients who may benefit from targeted-therapy allowing for optimization of individualized treatment.

Early Response of Hepatocellular Carcinoma to Chemoembolization: Volume Computed Tomography Liver Perfusion Imaging as a Short-Term Response Predictor.

The aim of this study was to investigate the efficacy of lesion-oriented whole-liver computed tomography (CT) perfusion for predicting transarterial chemoembolization early treatment response in patients with hepatocellular carcinoma (HCC). Volume helical shuttle CT perfusion imaging on the whole liver was prospectively performed on 39 patients with 46 independent HCC lesions before target-selected chemoembolization. The therapeutic effects were assessed: responder group included lesions with a complete and partial response, whereas the nonresponder group contained stable and progressive disease. The perfusion parameter value comparison between 2 groups and receiver operating characteristic analyses were performed. The responders demonstrated higher hepatic arterial perfusion (HAP) and hepatic arterial perfusion index (HAPI) and lower hepatic portal perfusion (HPP) compared with the nonresponders among the 34 lesions without Vp3 or Vp4 portal vein thrombosis. In addition, HAP and HAPI had good prognostic values. Whole-liver CT perfusion allows for hemodynamic evaluation of HCC lesions. The HAP, HAPI, and hepatic portal perfusion values may be useful predictors of short-term therapeutic response after transarterial chemoembolization.

Observation of the effect of targeted therapy of 64-slice spiral CT combined with cryoablation for liver cancer.

AIMTo observe the effect of targeted therapy with 64-slice spiral computed tomography (CT) combined with cryoablation for liver cancer.METHODSA total of 124 patients (142 tumors) were enrolled into this study. According to the use of dual-slice spiral CT or 64-slice spiral CT as a guide technology, patients were divided into two groups: dual-slice group (n = 56, 65 tumors) and 64-slice group (n = 8, 77 tumors). All patients were accepted and received targeted therapy by an argon-helium superconducting surgery system. The guided scan times of the two groups was recorded and compared. In the two groups, the lesion ice coverage in diameter of ≥ 3 cm and < 3 cm were recorded, and freezing effective rate was compared. Hepatic perfusion values [hepatic artery perfusion (HAP), portal vein perfusion (PVP), and the hepatic arterial perfusion index (HAPI)] of tumor tissues, adjacent tissues and normal liver tissues at preoperative and postoperative four weeks in the two groups were compared. Local tumor changes were recorded and efficiency was compared at four weeks post-operation. Adverse events were recorded and compared between the two groups, including fever, pain, frostbite, nausea, vomiting, pleural effusion and abdominal bleeding.RESULTSGuided scan times in the dual-slice group was longer than that in the 64-slice group (t = 11.445, P = 0.000). The freezing effective rate for tumors < 3 cm in diameter in the dual-slice group (81.58%) was lower than that in the 64-slice group (92.86%) (χ2 = 5.707, P = 0.017). The HAP and HAPI of tumor tissues were lower at four weeks post-treatment than at pre-treatment in both groups (all P < 0.05), and those in the 64-slice group were lower than that in the dual-slice group (all P < 0.05). HAP and PVP were lower and HAPI was higher in tumor adjacent tissues at post-treatment than at pre-treatment (all P < 0.05). Furthermore, the treatment effect and therapeutic efficacy in the dual-slice group were lower than the 64-slice group at four weeks post-treatment (all P < 0.05). Moreover, pleural effusion and intraperitoneal hemorrhage occurred in patients in the dual-slice group, while no complications occurred in the 64-slice group (all P < 0.05).CONCLUSION64-slice spiral CT applied with cryoablation in targeted therapy for liver cancer can achieve a safe and effective freezing treatment, so it is worth being used.

The value of 64-slice spiral CT perfusion imaging in the treatment of liver cancer with argon-helium cryoablation.

We analyzed the effectiveness of using 64-slice spiral computed tomography (CT) and perfusion imaging to guide argon-helium cryoablation treatment of liver cancer. In total, 60 cases of advanced hepatocellular carcinoma before surgery treated with argon-helium cryoablation were inlcuded in the present study. Retrospective summary of the 60 cases of metaphase and advanced liver cancer were used as the control group. The control group were treated using cryoablation with argon-helium knife. We used enhanced scanning with 64-slice spiral CT to define the extent of their lesions and prepared a plan of percutaneous cryoablation for the treatment. Intraoperatively, we used the dynamics of CT perfusion imaging to observe the frozen ablation range and decreased the rate of complications. After surgery, the patients were followed-up regularly by 64-slice CT. We used conventional X-ray, CT and magnetic resonance imaging (MRI) for pre-operative lateralization. Intraoperative X-ray or ultrasound guidance and follow-up with CT or MTI were added to determine the clinical effectiveness and prognosis. The results showed that the total effective rate was improved significantly and incidence rate of overall complications decreased markedly in the observation group. Following treatment, AFP decreased significantly while the total freezing area and time were reduced significantly. The median survival time was increased significantly in the observation group. The numeric values of hepatic arterial perfusion, portal vein perfusion and hepatic arterial perfusion index were all markedly lowered after treatment. Differences were statistically significant (P<0.05). In conclusion, the use of 64-slice spiral CT perfusion imaging may considerably improve the effects of liver cancer treatment using the argon-helium cryoablation. It extended the survival time and reduced complications.

Value of dynamic contrast-enhanced MRI parameters of Extended Tofts and Exchange model in the differential diagnosis of hepatocellular carcinoma and hepatic metastases

Objective To analyze the value of dynamic contrast-enhanced MRI(DCE-MRI) parameters of Extended Tofts and Exchange model in the differential diagnosis of hepatocellular carcinoma (HCC) and hepatic metastases of colorectal cancer. Methods A retrospective analysis of 40 pathologically confirmed cases was conducted, including 25 cases of HCC and 15 cases of hepatic metastases of colorectal cancer,all patients underwent DCE-MRI. Applying liver double blood supplement model, and respectively using Extended Tofts two-compartment model and Exchange model liver microvascular permeability parameters [volume transfer constant of the contrast agent(Ktrans), efflux rate from extracellular extravascular space to plasma(Kep), extravascular extracellular volume fraction(Ve)and blood plasma space volume fraction (Vp)] and the perfusion parameter hepatic arterial perfusion index(HPI) in the lesion parenchyma of HCC and metastases were calculated. We used t test to compare the differences of the parameters measured from the two types of tumors, statistically significant parameters between HCC and metastases were screened which compared with the gold standard of pathological findings in order to draw the ROC curves to evaluate the diagnostic efficacy of different model parameters, using χ2 test compared the diagnostic accuracy of optimal parameters between the two models. Results By using Extended Tofts and Exchange model, Ktrans value of HCC were (0.661±0.402)/min and (0.604±0.316)/min respectively, Ktrans value of hepatic metastases were (0.196±0.175)/min and (0.179±0.135)/min respectively; Vp value of HCC were (0.334±0.217) and (0.294±0.098), Vp value of hepatic metastases were (0.089±0.015) and (0.089±0.022),respectively; HPI value of HCC were (0.680±0.281) and (0.769±0.245), HPI value of hepatic metastases were (0.326±0.216), (0.373±0.298), respectively. There were significant differences between HCC and hepatic metastases in Ktrans, Vp and HPI values in both models(P 0.05).Drawn ROC curves of Ktrans, Vp, HPI, the Ktrans value (area under the curve of 0.869) among Extended Tofts model parameters was selected as optimal parameter to identify HCC and hepatic metastases; the HPI value (area under the curve of 0.845) among Exchange model parameters was selected as optimal parameter to differentiate these two types of tumors.The diagnostic accordance rate of Extended Tofts model and Exchange model were 80.0% (32/40) , 82.5% (33/40), respectively; There was no significant difference between them (χ2=0.082, P=0.775). Conclusions Parameters including Ktrans, Vp, HPI of the Extended Tofts model and Exchange model in DCE-MRI perfusion can be used to identify HCC and hepatic metastases of colorectal cancer. Among these parameters, Ktrans of Extended Tofts model and HPI of Exchange model have higher diagnostic value in differentiating HCC and hepatic metastases of colorectal cancer. Key words: Liver neoplasms; Magnetic resonance imaging; Comparative study

The clinical application of 320-detector row CT in transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma.

To evaluate the clinical value of 320-detector row CT in transcatheter arterial chemoembolization (TACE) treatment for hepatocellular carcinoma (HCC). Sixty-four patients with HCC underwent CT perfusion scanning with a 320-detector row CT before and after TACE. With the help of built-in dual-source CT perfusion software, color perfusion images of hepatic arterial perfusion (HAP), portal vein perfusion (PVP) and hepatic arterial perfusion index (HAPI) of all HCC lesions were obtained, and the above perfusion parameters were measured on the color images. The parameters obtained after TACE were compared with those obtained before TACE, and the differences were statistically analyzed. There were significant differences in HAP, PVP and HAPI between cancer tissues and non-cancerous tissues before TACE (P < 0.05). HCC necrotic tissues had no blood perfusion after TACE. Lower HAP and HAPI and higher PVP were observed in active cancer tissues after operation as compared with those before operation. The 320-row CT upper abdominal one-stop examination can display the whole liver perfusion well, especially the abnormal perfusion of HCC tissues and postoperative active tissues. Angiography can display the hepatic and nutrient arteries of tumors from three dimensions, and has important guiding significance in preoperative evaluation and postoperative follow up of TACE.

[Hemodynamic study of hepatocellular carcinoma nodules by multi-slice spiral computed tomographic perfusion].

To analyze the 64-slice computed tomographic (CT) perfusion parameters of hepatocellular carcinoma (HCC) nodule so as to assess the diagnostic value of hemodynamic changes of HCC nodule by this perfusion technique. Forty volunteers without liver disease (control subjects) and 37 HCC patients (experimental group) were selected. After informed consents, all of them underwent plain, perfusion and contrast CT examinations. Perfusion CT scan was performed at 120 kV, 60 mA and a thickness of up to 40 mm. The injection rate of contrast medium was 4 - 5 ml/sec at a dose of 1.0 ml/kg body weight. And 50 seconds of continuous scanning time was set at 5 seconds post-injection. The indices were 1 second per 360° revolution, 5 mm slice thickness image reconstruction and a matrix size of 512×512 pixels. Perfusion parameters associated with changes in hepatic blood flow included blood flow (HBF), hepatic blood volume (HBV), hepatic arterial perfusion index (HAI), hepatic artery perfusion (HAP) and portal venous perfusion (HPP). Perfusion parameters were measured thrice at each time point for each different region of interest (ROI): hepatic parenchyma surrounding HCC nodule, HCC nodule and normal liver parenchyma(control group). For HCC nodule, the increased levels of HBF, HAP and HAI were significantly differentiated from normal liver parenchyma of control group (P < 0.01). Increased HBV and decreased HPP had no difference from control group (P > 0.05). Higher levels of HAP, HPP and HAI in HCC nodules were differentiated from hepatic parenchyma surrounding HCC nodules (P < 0.05). HBV decreased and HBF increased in HCC nodule. But it had no differences from hepatic parenchyma surrounding HCC nodule (P > 0.05). Perfusion CT may visualize the status of liver blood flow caused by HCC nodule so as to serve as a new tool of studying the hemodynamic changes of HCC nodules.

[Evaluation of graft perfusion in patients with ischemic-type of biliary lesions after liver transplantation].

To investigate the value of 320-rows CT perfusion (CTP) imaging in the study of hepatic hemodynamic characters in ischemic-type biliary lesions (ITBL) after liver transplantation. A total of 11 ITBL patients received 320-slice CT angiography (CTA) and CTP after liver transplantation scheduled at 5-10 min away. Four patients underwent liver biopsy While 7 patients with normal liver after transplantation were selected as the control group. The parameters of hepatic artery perfusion (HAP), portal vein perfusion (PVP), total hepatic perfusion (TLP) and hepatic arterial perfusion index (HPI) were measured and compared for all patients. And the blood perfusion characters of liver with ITBL after transplantation were analyzed. (1) In 11 ITBL patients, 3 patients had no vascular complications on CTA, 1 with simple hepatic artery stenosis (HAS), 1 with HAS and arterioportal shunt (APS), 2 with HAS and portal vein stenosis/right hepatic vein stenosis (PVS/RHVS), 1 with simple APS, 2 with simple PVS and 1 with portal vein thrombosis and cavernous transformation of portal vein (PVT and CTPV). And 4/11 patients underwent liver biopsy, 2 in which confirmed mild acute rejection and 2 confirmed biliary obstruction associated with ascending biliary infection.(2) HAP of the ITBL and control groups were (66 ± 38) and (40 ± 8) ml×min(-1)·(100 ml)(-1), PVP (128 ± 35) and (163 ± 21) ml×min(-1)·(100 ml)(-1), TLP (194 ± 58) and (203 ± 19) ml×min(-1)·(100 ml)(-1), HPI 34% ± 14% and 21% ± 4% respectively. The differences in the value of HAP, PVP and HPI between the groups were statistically significant (P < 0.05) excluding TLP. Various liver perfusion abnormalities of ITBL may be evaluated objectively by CTP. ITBL might occurred when HAP and HPI increased with a decreased of PVP.

Adipose derived mesenchymal stem cells transplantation via portal vein improves microcirculation and ameliorates liver fibrosis induced by CCl4 in rats

IntroductionAdipose derived mesenchymal stem cells (ADMSCs), carrying the similar characteristics to bone marrow mesenchymal stem cells, only much more abundant and easier to obtain, may be a promising treatment for liver fibrosis. We aim to investigate the therapeutic potential of ADMSCs transplantation in liver fibrosis caused by carbon tetrachloride (CCl4) in rats as well as its underlying mechanism, and to further explore the appropriate infusion pathway.MethodsADMSCs were isolated, cultured and identified. Placebo and ADMSCs were transplanted via portal vein and tail vein respectively into carbon tetrachloride (CCl4)-induced liver fibrosis rats. Computed tomography (CT) perfusion scan and microvessel counts were performed to measure the alteration of liver microcirculation after therapy. Liver function tests and histological findings were estimated.ResultsCT perfusion scan shown significant decrease of hepatic arterial perfusion index, significant increased portal vein perfusion, total liver perfusion in rats receiving ADMSCs from portal vein, and Factor VIII (FVIII) immunohistochemical staining shown significant decrease of microvessels in rats receiving ADMSCs from portal vein, indicating microcirculation improvement in portal vein group. Vascular endothelial growth Factor (VEGF) was significantly up-regulated in fibrosis models, and decreased after ADMSCs intraportal transplantation. A significant improvement of liver functional test and histological findings in portal vein group were observed. No significance was found in rats receiving ADMSCs from tail vein.ConclusionsADMSCs have a therapeutic effect against CCl4-mediated liver fibrosis. ADMSCs may benefit the fibrotic liver through alteration of microcirculation, evidenced by CT perfusion scan and down-regulation of VEGF. Intraportal transplantation is a better pathway than tail vein transplantation.

Computed Tomographic Perfusion Imaging for the Therapeutic Response of Chemoembolization for Hepatocellular Carcinoma

Computed tomographic (CT) perfusion imaging has been applied in many clinical areas, but few studies have addressed the values of CT perfusion imaging in evaluating the therapeutic response of chemoembolization for hepatocellular carcinoma (HCC). To assess the perfusion changes of HCC after transarterial chemoembolization, and to investigate the values of CT perfusion imaging in chemoembolization procedure. Multidetector computed tomographic perfusion imaging was performed in 24 patients with HCC 1 week before and 4 weeks after chemoembolization. The CT perfusion parameters, including hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP), total liver perfusion (TLP), and hepatic arterial perfusion index (HAPI), were calculated by using the slope method. The t statistic was used to analysis the difference of CT perfusion parameter values before and after chemoembolization therapy. The values of HAP, TLP, and HAPI in tumors 4 weeks after chemoembolization were significantly decreased than those before chemoembolization (P < 0.05), but the value of HPP in tumors was not (P > 0.05). Computed tomographic perfusion imaging has the ability to evaluate the perfusion changes in HCC after chemoembolization, which can be used to evaluate the therapeutic response of chemoembolization for hepatocellular carcinoma.

Correlation between Tumor Perfusion and Lipiodol Deposition in Hepatocellular Carcinoma after Transarterial Chemoembolization

To study the correlation of tumor perfusion with lipiodol deposition in hepatocellular carcinoma (HCC) after transarterial chemoembolization with multidetector computed tomography (MDCT) perfusion imaging. MDCT perfusion imaging was performed in 24 patients with HCC 1 to 7 days before chemoembolization. The computed tomography (CT) perfusion parameters, such as hepatic arterial perfusion (HAP), hepatic portal perfusion (HPP), total liver perfusion (TLP), and hepatic arterial perfusion index (HAPI), were calculated with the slope method. The follow-up CT scans (noncontrast) were performed 4 weeks after chemoembolization to analyze lipiodol deposition. The lipiodol deposition in the tumor was classified into three grades and compared with CT perfusion parameters before chemoembolization. The HAP and TLP of tumors before chemoembolization were correlated with the grades of lipiodol deposition in tumors after chemoembolization (r = 0.768, P < .0001 and r = 0.616, P = .001, respectively). However, the HPP and HAPI of the tumors were not related to the grades of iodized oil deposition (r = 0.227, P = .286 and r = 0.111, P = .607, respectively). Higher HAP was correlated with better lipiodol deposition, and lower HAP was correlated with poorer lipiodol deposition. MDCT perfusion imaging has the potential to help select more appropriate patients with HCC for chemoembolization.

Application of CT perfusion imaging in diagnosing liver cancer

Hepatic perfusion data such as hepatic blood flow, hepatic blood volume, hepatic arterial perfusion index etc, can be obtained by CT perfusion imaging (CTPI)with quantitative measurements of local blood flow to the liver. As the data mentioned above are varied in different tissues, e. g normal liver parenchyma, cirrhotic liver, hepatocellular carcinoma(HCC) and secondary liver cancer(SLC),the differential diagnosis of liver lesions, especially the early subclinical liver cancer, can be made by analyzing the related data. The principle of CTPI, the main points for differential diagnosis between HCC and SLC, the relationship between CTPI and micro-vessel density(MVD), the changes of CTPI pre-and post-TACE, as well as diagnostic sensitivity of CTPI and contrast enhanced ultrasound(CEUS) in patients with liver cancer were introduced in this article. Key words: CT perfusion imaging;  Liver cancer; Diagnosis;  Differential diagnosis