Contrast enhanced computed tomography and reconstruction of hepatic vascular system for transjugular intrahepatic portal systemic shunt puncture path planning

A meta-analysis of the three-dimensional reconstruction visualization technology for hepatectomy

This meta-analysis was conducted to systematically evaluate the short-term efficacy and safety of the three-dimensional (3D) reconstruction visualization technology (3D-RVT) technique for hepatectomy. A systematic literature search was used to gather information on the 3D reconstruction visualization technology technique for hepatectomy from retrospective cohort studies and comparative studies. The retrieval period was up to March 2022. Publications and conference papers in English were manually searched and references in bibliographies traced. After evaluating the quality of selected studies, a meta-analysis was conducted using Review Manager 5.1 software. We included 12 studies comprising 2053 patients with liver disease. Our meta-results showed that 3D-RVT significantly shortened operation times [weighted mean differences (WMD) = -29.36; 95% confidence interval (CI): -55.20 to -3.51; P = 0.03], reduced intraoperative bleeding [WMD = -93.53; 95% CI: -152.32 to -34.73; P = 0.002], reduced blood transfusion volume [WMD = -66.06; 95% CI: -109.13 to -22.99; P = 0.003], and shortened hospital stays [WMD = -1.90; 95% CI: -3.05 to -0.74; P = 0.001]. Additionally, the technique reduced the use of hepatic inflow occlusion and avoided overall postoperative complications [odds ratio (OR) = 0.60; 95% CI: 0.46 to 0.79; P < 0.001]. 3D-RVT is safe and effective for liver surgery and provides safety assessments before anatomical hepatectomy.

Influence of different portal vein branches on hepatic encephalopathy during intrahepatic portal shunt via jugular vein

This letter is regarding the study titled ‘Targeted puncture of left branch of intrahepatic portal vein in transjugular intrahepatic portosystemic shunt (TIPS) to reduce hepatic encephalopathy’. Prior to the approval of TIPS dedicated stents (Viatorr stents) in China in October 2015, Fluency covered stents were typically used. As Fluency covered stents have a strong support force and axial elastic tension, a ‘cap’ may form if the stent is located too low at the end of the hepatic vein or too short at the end of the portal vein during surgery, leading to stent dysfunction. Since the blood shunted by the stent is from the main trunk of the portal vein, the correlation between the incidence of postoperative hepatic encephalopathy and the location of the puncture target (left or right portal vein branch) is worth discussion. Notably, no studies in China or foreign countries have proven the occurrence of left and right blood stratification after the accumulation of splenic vein and mesenteric blood flow in the main trunk of the portal vein in patients with cirrhotic portal hypertension.

Applications of vascular interventions in hypersplenism in liver cirrhosis

Cirrhosis is a common cause of secondary hypersplenism. Hypersplenism often leads to a decrease in peripheral blood cells, and when the numbers of leukocytes and platelets are severely reduced, patients are prone to spontaneous infections and bleeding, which can aggravate the disease and increase the risk of death. The mechanism of hypersplenism in cirrhosis is not well understood, and there is no standard indication or recommended method for the treatment of hypersplenism. Clinical treatment options for hypersplenism include splenectomy, vascular intervention, local thermal ablation, and splenic artery ligation. Vascular interventions mainly involve transjugular intrahepatic portosystemic shunt (TIPS) and partial splenic embolization (PSE). TIPS is an effective method to treat the complications of portal hypertension in cirrhosis, which can effectively reduce portal pressure, but whether it can relieve hypersplenism is still controversial. PSE can relieve hypersplenism to a certain extent. TIPS combined with PSE can effectively reduce portal hypertension and relieve hypersplenism to a certain extent. This article reviews the applications of vascular interventions in hypersplenism in cirrhosis.

Portal vein puncture-related complications during transjugular intrahepatic portosystemic shunt creation: Colapinto needle set vs Rösch-Uchida needle set

Transjugular portal vein puncture is considered the riskiest step in TIPS creation with possible incidence of portal vein puncture-related complications (PVPC). The Colapinto and the Rösch-Uchida needle sets are two different needle sets currently available. To date, there have been no randomized control trials or systematic reviews which compare the incidence of PVPC when using the two different needle sets. The aim of this literature review is to assess the rate of PVPC associated with the different needle sets used in the creation of TIPS. From the described search, 1500 articles were identified and 34 met the inclusion criteria. Outcome measured was the prevalence of PVPC using the different needle sets. Overall 212 (3.6%) PVPC were reported in 5865 patients; 142 (3.5%) reported in 4000 cases using the Rösch-Uchida set and 70 (3.7%) in 1865 patients using the Colapinto set (p = 0.69). PVPC in TIPS creation are not related to the choice of needle set used in the procedure. To our knowledge, this is the first review of its kind, the results of which support the theory that while the rate of PVPC is influenced by many factors, choice of needle set does not seem to be one of them.

Clinical efficacy of antiviral therapy in patients with hepatitis B-related cirrhosis after transjugular intrahepatic portosystemic shunt

BACKGROUND

As a country with a high burden of hepatitis B, China has about 86 million cases of hepatitis B virus infection, ranking the first in the world. Currently, there are about 390000 deaths due to hepatitis B-related complications such as liver cirrhosis and liver cancer every year. Consequently, how to control portal hypertension, improve liver functional reserve, and reduce the incidence of hepatic failure and liver cancer in such patients is the focus of current clinical attention. Previous clinical study in our center suggested that at 24 mo after transjugular intrahepatic portosystemic shunt (TIPS), the liver functional reserve of patients with hepatitis B cirrhosis was better than that of patients with alcohol-induced and immune cirrhosis, which may be related to the effective etiological treatment.

AIM

To investigate the clinical efficacy of three first-line antiviral drugs recommended by the guidelines of prevention and treatment for chronic hepatitis B in China (2019) in the treatment of patients with hepatitis B-related cirrhosis who had received a TIPS.

METHODS

The clinical data of 137 patients with hepatitis B-related cirrhosis with portal hypertension after receiving TIPS at our centre between March 2016 and December 2020 were analysed retrospectively. According to different anti-viral drugs, the patients were divided into entecavir (ETV) (n = 70), tenofovir alafenamide fumarate (TAF) (n = 32), and tenofovir disoproxil fumarate (TDF) (n = 35) groups. The cumulative incidence of hepatic encephalopathy and hepatocellular carcinoma, survival, and changes in hepatic reserve function and glomerular filtration rate in patients treated with different antiviral drugs within 24 mo after surgery were investigated.

RESULTS

At 24 mo after surgery, the Child–Pugh score in the TAF group (6.97 ± 0.86) was lower than that in the TDF (7.49 ± 0.82; t = -2.52, P = 0.014) and ETV groups (7.64 ± 1.17; t = -2.92, P = 0.004). The model for end-stage liver disease score in the TAF group at 24 mo after surgery was 9.72 ± 1.5, which was lower than that in the TDF (10.74 ± 2.33; t = -2.09, P = 0.040) and ETV groups (10.97 ± 2.17; t = -2.93, P = 0.004). At 24 mo after surgery, the estimated glomerular filtration rate (eGFR) in the TAF group (104.41 ± 12.54) was higher than that in the TDF (93.54 ± 8.97) and ETV groups (89.96 ± 9.86) (F = 21.57, P < 0.001).

CONCLUSION

At 24 mo after surgery, compared with TDF and ETV, TAF has significant advantages in the improvement of liver functional reserve and eGFR.

Effects of transjugular intrahepatic portosystemic shunt using the Viatorr stent on hepatic reserve function in patients with cirrhosis

BACKGROUND

As transjugular intrahepatic portosystemic shunt (TIPS) creation alters the hemodynamic status of the portal system, whether reduced portal blood supply affects the synthetic reserve function of the liver has been the focus of clinical attention. Since the Viatorr stent entered the Chinese market in 2015, it has not yet been widely used in clinical practice. Further, unlike other countries, the main cause of liver cirrhosis in China is viral hepatitis. Therefore, use of the Viatorr stent to establish a TIPS channel in patients with liver cirrhosis with differing etiologies is of great clinical interest.

AIM

To investigate factors affecting changes in liver reserve function after TIPS Viatorr stent implantation.

METHODS

Clinical data from 200 patients with cirrhotic portal hypertension who received TIPS treatment from March 2016 to March 2020 were analyzed retrospectively. The patients were divided into three groups (A-C), according to their disease etiology, with post-hepatitis, autoimmune, and alcoholic cirrhosis, respectively. Preoperative and postoperative liver and renal function and coagulation data, Child-Pugh grade, and model for end-stage liver disease (MELD) scores were collected. Statistical analyses were performed using the t-test or chi-square test. The incidence and of hepatic encephalopathy and patient survival were calculated using Kaplan-Meier method.

RESULTS

The surgical success rate was 100%, with mean portal pressure gradient (mmHg) decreasing from 25.5 ± 5.22 to 10.04 ± 2.76 (t = 45.80; P < 0.001). After 24 mo, the cumulative incidence of hepatic encephalopathy in group A was significantly lower than that in group B/C, while the cumulative survival rate was significantly higher in group A than in group B/C (P < 0.05 for both). The Child-Pugh score for group A was 6.96 ± 1.21, which was significantly better than those of groups B (7.42 ± 0.99; t = -2.44; P = 0.016) and C (7.52 ± 1.12; t = -2.67; P = 0.009). Further, the MELD score for group A (9.62 ± 2.19) was significantly better than those for groups B (10.64 ± 1.90; t = -2.92; P = 0.004) and C (10.82 ± 2.01; t = -3.29; P = 0.001).

CONCLUSION

Insertion of 8 mm internal diameter Viatorr stent has no significant effects on liver reserve function. Changes of liver reserve function in the medium and long term may be related to the etiology and treatment of portal hypertension.

Feasibility of Augmented Reality-Guided Transjugular Intrahepatic Portosystemic Shunt

PURPOSE

To investigate an augmented reality (AR)-guided endovascular puncture to facilitate successful transjugular intrahepatic portosystemic shunt (TIPS).

MATERIALS AND METHODS

An AR navigation system for TIPS was designed. Three-dimensional (3D) liver models including portal and hepatic vein anatomy were extracted from preoperative CT images. The 3D models, intraoperative subjects, and electromagnetic tracking information of the puncture needles were integrated through the system calibration. In the AR head-mounted display, the 3D models were overlaid on the subjects, which was a liver phantom in the first phase and live beagle dogs in the second phase. One life-size liver phantom and 9 beagle dogs were used in the experiments. Imaging after puncture was performed to validate whether the needle tip accessed the target hepatic vein successfully.

RESULTS

Endovascular punctures of the portal vein of the liver phantom were repeated 30 times under the guidance of the AR system, and the puncture needle successfully accessed the target vein during each attempt. In the experiments of live canine subjects, the punctures were successful in 2 attempts in 7 beagle dogs and in 1 attempt in the remaining 2 dogs. The puncture time of needle from hepatic vein to portal vein was 5-10 s in the phantom experiments and 10-30 s in the canine experiments.

CONCLUSIONS

The feasibility of AR-based navigation facilitating accurate and successful portal vein access in preclinical models of TIPS was validated.

Portosystemic shunt surgery in the era of TIPS: imaging-based planning of the surgical approach

PURPOSE

With the spread of transjugular intrahepatic portosystemic shunts (TIPS), portosystemic shunt surgery (PSSS) has decreased and leaves more complex patients with great demands for accurate preoperative planning. The aim was to evaluate the role of imaging for predicting the most suitable PSSS approach.

MATERIAL AND METHODS

Forty-four patients who underwent PSSS (2002 to 2013) were examined by contrast-enhanced CT (n = 33) and/or MRI (n = 15) prior to surgery. Imaging was analyzed independently by two observers (O1 and O2) with different levels of experience (O1 > O2). They recommended two shunting techniques (vessels and anastomotic variant) for each patient and ranked them according to their appropriateness and complexity. Findings were compared with the actually performed shunt procedure and its outcome.

RESULTS

The first two choices taken together covered the performed PSSS regarding vessels in 88%/100% (CT/MRI, O1) and 76%/73% (O2); and vessels + anastomosis in 79%/73% (O1) and 67%/60% (O2). The prediction of complex surgical procedures (resection of interposing structures, additional thrombectomy, use of a collateral vessel, and use of a graft interposition) was confirmed in 87%, resulting in 80% sensitivity and 96% specificity. Larger shunt vessel distances were associated with therapy failure (p = 0.030) and a vessel distance of ≥ 20 mm was identified as optimal cutoff, in which a graft interposition was used. There was no significant difference between MRI and CT in predicting the intraoperative decisions (p = 0.294 to 1.000).

CONCLUSION

Preoperative imaging and an experienced radiologist can guide surgeons in PSSS. CT and MRI provide the information necessary to identify technically feasible variants and complicating factors.

Consensus recommendations of three-dimensional visualization for diagnosis and management of liver diseases

Three-dimensional (3D) visualization involves feature extraction and 3D reconstruction of CT images using a computer processing technology. It is a tool for displaying, describing, and interpreting 3D anatomy and morphological features of organs, thus providing intuitive, stereoscopic, and accurate methods for clinical decision-making. It has played an increasingly significant role in the diagnosis and management of liver diseases. Over the last decade, it has been proven safe and effective to use 3D simulation software for pre-hepatectomy assessment, virtual hepatectomy, and measurement of liver volumes in blood flow areas of the portal vein; meanwhile, the use of 3D models in combination with hydrodynamic analysis has become a novel non-invasive method for diagnosis and detection of portal hypertension. We herein describe the progress of research on 3D visualization, its workflow, current situation, challenges, opportunities, and its capacity to improve clinical decision-making, emphasizing its utility for patients with liver diseases. Current advances in modern imaging technologies have promised a further increase in diagnostic efficacy of liver diseases. For example, complex internal anatomy of the liver and detailed morphological features of liver lesions can be reflected from CT-based 3D models. A meta-analysis reported that the application of 3D visualization technology in the diagnosis and management of primary hepatocellular carcinoma has significant or extremely significant differences over the control group in terms of intraoperative blood loss, postoperative complications, recovery of postoperative liver function, operation time, hospitalization time, and tumor recurrence on short-term follow-up. However, the acquisition of high-quality CT images and the use of these images for 3D visualization processing lack a unified standard, quality control system, and homogeneity, which might hinder the evaluation of application efficacy in different clinical centers, causing enormous inconvenience to clinical practice and scientific research. Therefore, rigorous operating guidelines and quality control systems need to be established for 3D visualization of liver to develop it to become a mature technology. Herein, we provide recommendations for the research on diagnosis and management of 3D visualization in liver diseases to meet this urgent need in this research field.

Method for Calculating the Bending Angle of Puncture Needle in Preoperative Planning for Transjugular Intrahepatic Portal Systemic Shunt (TIPS)

Transjugular Intrahepatic Portal Systemic Shunt is a comprehensive interventional therapy for portal hypertension. During this intervention, puncturing from hepatic vein into portal vein is a difficult step. Selecting puncture needle with a proper bending angle is vital to accurate puncture. Thus, this prospective study provides a method to calculate the angle of the puncture needle using preinterventional contrast-enhanced CT imaging. According to the geometrical characteristics of puncture needle, Bezier curve equation was adopted to describe its bending part. By testing whether each point in a specific region satisfied the equation set of Bezier curves, the possible position of needle tip was obtained. Then, the bending angle of puncture needle was obtained by calculating curvature. The method was evaluated in 13 patients from 2 centers showing now a success rate of 100% and a duration of the procedure of 141 and 161 minutes. The method based on Bezier curve equation for calculating a proper bending angle of puncture needle was proven to be effective. And the clinical study is preliminary and additional work for clinical evaluation is necessary.