Expert consensus on precise diagnosis and treatment of hilar cholangiocarcinoma guided by three-dimensional visualization technology

Chinese Society of Digital Medicine; Chinese Research Hospital Association of Digital Surgery Committee

doi:10.4103/digm.digm_15_17

CONSENSUS

Year : 2017 | Volume : 3 | Issue : 2 | Page : 50-56

Expert consensus on precise diagnosis and treatment of hilar cholangiocarcinoma guided by three-dimensional visualization technology

Chinese Society of Digital Medicine, Chinese Research Hospital Association of Digital Surgery Committee
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Date of Web Publication

18-Sep-2017

Correspondence Address:

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/digm.digm_15_17

Abstract

The three-dimensional (3D) visualization technology in hilar cholangiocarcinoma could offer decision-making support to preoperative diagnosis, individualized surgical planning and then proffer operative approach. In addition,the 3D printing technology helps to realize the leapfrog development from 3D image to 3D physical models and proffers better guidance of the precise surgery for patients with hilar cholangiocarcinoma. To standardize the application of 3D visualization and 3D printing technology in the precise diagnosis and treatment of hilar cholangiocarcinoma ,Chinese Society of Digital Medicine and Chinese Research Hospital Association of Digital Surgery Committee organized experts in related fields to formulate this consensus.

Keywords: Clinical classification, hilar cholangiocarcinoma, three-dimensional printing, three-dimensional visualization, variation of portal vein

How to cite this article:
Chinese Society of Digital Medicine, Chinese Research Hospital Association of Digital Surgery Committee. Expert consensus on precise diagnosis and treatment of hilar cholangiocarcinoma guided by three-dimensional visualization technology. Digit Med 2017;3:50-6

How to cite this URL:
Chinese Society of Digital Medicine, Chinese Research Hospital Association of Digital Surgery Committee. Expert consensus on precise diagnosis and treatment of hilar cholangiocarcinoma guided by three-dimensional visualization technology. Digit Med [serial online] 2017 [cited 2023 Jun 10];3:50-6. Available from: http://www.digitmedicine.com/text.asp?2017/3/2/50/215024

Address for correspondence: Prof. Chihua Fang, Department of Hepatobiliary Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, Guangdong Province, China. E.mail: [email protected]

Introduction

Three-dimensional (3D) visualization for hilar cholangiocarcinoma is a technique to display, demonstrate, and analyze the morphological and 3D anatomical features of hilar cholangiocarcinoma. It utilizes computer image processing technology, together with computed tomography (CT) or magnetic resonance imaging (MRI) data, to analyze, confuse, calculate, segment, and delineate the morphological features or spatial arrangement of the targeted objections such as liver parenchyma, biliary tracts, vasculatures, and tumors. Through this advanced technique, we can reconstruct the targeted objections directly, precisely, and conveniently. This method provides precise preoperative diagnosis. Meanwhile, it also improves the strategy of individual operative scheme and operative approach.

To normalize and standardize the application of 3D visualization and 3D printing technique for diagnosis and treatment of hilar cholangiocarcinoma, the Chinese Society of Digital Medicine and the Chinese Research Hospital Association of Digital Surgery Committee organized experts in related fields to formulate this consensus.

Preoperative Assessment of Hilar Cholangiocarcinoma

Hilar cholangiocarcinoma is one of the most common biliary malignancy tumors. Surgical operation is the only treatment method for patients to obtain long-term survival.^[1],[2],[3] Recently, CT, MRI, and MRCP are the mainstream methods of imaging assessment for hilar cholangiocarcinoma. However, there are several shortcomings: (1) The data remain two dimensional, (2) those methods are unable to demonstrate the tumors, hepatic arteries, portal veins, and hepatic veins stereoscopically, and the related spatial relationships between them, (3) they are unable to apply multicolor and various transparency to display the overall arrangement of organs, tumors and vessels according to the diagnosis requirement, (4) they require professional medical imaging technologists to assist in the analysis of the imaging data, and (5) they are unable to process preoperative simulation operations according to the preoperative scheme. Recently, with the development of digital medicine technique and the theory and practice of precise diagnosis and treatment, 3D visualization and 3D printing technology have been rapidly developed in China and other countries. Compared with 2D imaging data such as CT and MRI, 3D visualization and 3D printing technology is more intuitive and precise.^[4] 3D visualization model has the ability to display the location, size, morphology, and allocation of the tumors clearly; to display the originals and variations of portal veins; and to display the spatial relationships of tumors with hepatic arteries and portal veins. Herein, it plays an important role in precise assessment of the location of lesion, evaluation of the relationships between tumors and portal veins and making precise operation plan. Now, 3D visualization is changing the conventional 2D diagnosis and treatment model for hilar cholangiocarcinoma. 3D printing technology of liver has transformed 3D visualization imaging planar model into a spatial model. With this advanced technique, we are able to explore the lesions at multidirectional and multi-aspect levels during the operations and to guide the operations for hilar cholangiocarcinoma more precisely.

Recommendation

For those patients who were diagnosed with hilar cholangiocarcinoma by B-type ultrasound, CT, or tumor marker, we propose to make further precise assessment by applying the 3D visualization to guide the strategy of operations.

The Collection of Thin-layer Computed Tomography Scanning Data for Hilar Cholangiocarcinoma

To collect high quality submillimeter CT data of intrahepatic ducts, those patients who have been diagnosed with hilar cholangiocarcinoma by B-type ultrasound should collect upper abdominal CT imaging data, especially those during the portal vein phase. They play an important role in the construction of 3D visualization models to obtain good signal to noise ratio data. Since hilar cholangiocarcinoma often invades portal veins, they are critical data for determining whether the operations could be performed or not.

Recommendation

Clinical doctors should accompany patients during the process of CT examinations and guide the technologists to collect high quality data of portal vein phase.

Construction of Three-dimensional Visualization Models of Hilar Cholangiocarcinoma

Analysis of computed tompgraphy data and three-dimensional reconstruction

Thin-layer CT imaging data are imported into 3D visualization imaging software system to perform programmed segmentation and reconstruction. Reading and analyzing carefully the imaging data are important for ensuring the accuracy of 3D visualization. Regulation of the transparency of hepatic parenchyma can display the liver and intrahepatic duct branches simultaneously. We are able to obtain accurate spatial relationship between different structures by observing the reconstruction models vortically.

Recommendation

A variety of software is applied to study 3D visualization. Most of them can be used on personal computers. We propose that this technique should be applied according to the conditions of the equipment.

3D visualization classification of portal vein^[5] displays the trunk of portal vein, and its second, third, fourth level branches; it is one of the most important preoperative assessments for hilar cholangiocarcinoma. In addition, the variation rate of portal vein is fairly high, so the analysis for 3D visualization model of portal vein is worthwhile. Through 3D visualization technology, we classify the portal veins into 5 types: (1) Normal type: The trunk of portal vein divides into left branch and right branch at hepatic hilum [Figure 1]a, (2) Type-I variation: The trunk of portal vein divides trifurcate directly into left branch, right-anterior branch and right posterior branch at hepatic hilum [Figure 1]b, (3) Type-II variation: The trunk of portal vein divides right posterior branch first, and then divides into right anterior and left branches during its upward process [Figure 1]c, (4) Type-III variation: Right branch of portal vein divides into posterior and anterior branches horizontally [Figure 1]d, and (5) Type-IV variation: Horizontal part of the left branch of portal vein is absent; special variation: Left branch of portal vein originates from the right anterior branch.

Figure 1: The operation scheme of variation of portal vein under the guiding guidance of three Three-dimensional visualization a: Common type; b: Type-I; c: Type-II; d: Type-IIILT: The left branch of portal vein. RA: The right anterior of portal vein; RP: The right posterior of portal vein

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Recommendation

3D visualization classification of portal vein for patients with hilar cholangiocarcinoma is helpful to understand their origins, variations, and relationships with tumors.

Three-dimensional Visualization for Individual Liver Segmentation and Volume Computing

For patients with hilar cholangiocarcinoma requiring combined right hemihepatectomy and extensive right hemihepatectomy, it is necessary to conduct liver segmentation and volume computing according to expert consensus of 3D visualization precise diagnosis and treatment for complicated hepatic tumors.

Recommendation

For patients with hilar cholangiocarcinoma requiring combined right hemihepatectomy and extensive right hemihepatectomy, conducting liver segmentation and volume computing is necessary.

Three-dimensional Visualization Clinical Classification for Hilar Cholangiocarcinoma

Bismuth-Corlette classification was used to evaluate the extent of tumor invasion in biliary tract.^[6] MSKCCT grade system was used to evaluate the extent of tumor invasion in portal vein and the condition of liver atrophy.^[7] Combining their advantages, we classify hilar cholangiocarcinoma into 5 types [Figure 2]. As the result of 3D visualization is not able to define the characteristics of lymph nodes, this consensus does not involve the content of this field.

Figure 2: Clinical classification for hilar cholangiocarcinoma based on application of three-dimensional visualization technology a. Type I b. Type II c. Type IIIa d. Type IIIb e. Type IVa f. Type IVb g. Type V PV: Portal vein BD: Bile duct HA: He

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Type-I: The tumor invades common biliary duct, and does not invade the confluence part of the right hepatic duct and left hepatic duct, hepatic artery, and portal vein; there is no liver segment or sector atrophy
Type-II: The tumor invades the confluence of right hepatic duct and left hepatic duct, with/without invasion of hepatic artery and/or portal vein, without liver segment or sector atrophy
Type-IIIa: The tumor invades the confluence of right hepatic duct and left hepatic duct, mainly the right hepatic duct, with the invasion of right hepatic artery or right branch of portal vein, with/without right-sided liver sector and/or liver segment atrophy
Type-IIIb: The tumor invades the confluence of right hepatic duct and left hepatic duct, mainly the left hepatic duct, with the invasion of left hepatic artery or left branch of portal vein, with/without left-sided liver sector and/or liver segment atrophy
Type-IVa: The tumor invades the confluence of right hepatic duct and left hepatic duct, the right-sided second-grade biliary duct is involved, with right hepatic artery or right branch of portal vein invasion; tumor has not spread beyond theP point, with right-sided liver segment or liver sector atrophy
Type-IVb: The tumor invades the confluence of right hepatic duct and left hepatic duct, the left-side second-grade biliary duct is involved, with left hepatic artery or left branch of portal vein invasion; the tumor has not spread beyond the U point, with left-sided liver segment or liver sector atrophy
Type-V: The extent of tumor invasion spreads beyond bilateral resection limitation points; right and left hepatic arteries, and left branch and right branch of portal vein are involved, with/without total liver atrophy.

Recommendation

Evaluating and assessing patients with hilar cholangiocarcinoma according to 3D visualization clinical classification helps surgeons to choose proper surgical strategies and exhaustive operation plans.

Three-dimensional Visualization and Three-dimensional Printing for Hilar Cholangiocarcinoma

For patients with hilar cholangiocarcinoma, who require right hemi-hepatectomy/extended right hemihepatectomy, partial resection of hepatic artery/portal vein, reconstruction of blood vessels, 3D visualization and 3D printing should be performed based on research and analysis of 3D visualization [Figure 3]. This method can be used intraoperatively to guide precise operation.^[8],[9]

Figure 3: The P point and U points displayed clearly by Three-dimensional printing model the P point displayed clearly by Three-dimensional printing model the U point displayed clearly by Three-dimensional printing model PV: Portal vein BD: Bile duct, HA: Hepatic artery, TUMOR: Tumor HMV: The hepatic vein, LT: The left branch of portal vein, RA: The right anterior branch of portal vein, RP: The right posterior branch of portal vein

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Recommendation

For patients with hilar cholangiocarcinoma, we propose to perform preoperative 3D visualization and 3D printing based on the conditions of technology and equipment.

Three-dimensional Visualization Guides Precise Treatment for Hilar Cholangiocarcinoma

According to the analytical results of 3D visualization clinical classification, specific types are confirmed. Based on individual conditions and precise locations of theP and U points, and on the literature, a variety of basic operative plans is formulated.^{[10],[11],[12],[13]} In addition, based on the results of intraoperative pathological examination and experiences of surgeons, exhaustive operation approach is selected.^[14]

Recommendation

We propose to select rational operative plan based on the 3D visualization classification and 3D printing technology.

Three-dimensional Visualization Guides Operation Plan for Hilar Cholangiocarcinoma With Blood Vessel Variation

3D visualization guides operation plan for hilar cholangiocarcinoma with portal vein variation [Figure 1]. The limited dissection point of portal vein and biliary duct^[15] of normal type (U point: The reverse turn of horizontal part and sagittal part of portal vein left branch;P point: The bifurcation of right-anterior branch and right posterior branch of portal vein) refers to the limited location where biliary ducts can be dissected from the parallel structures such as portal veins and hepatic arteries during the hepatectomy. Biliary ducts above the limited.

Points are not able to be dissected and resected separately. By performing 3D visualization analysis and liver 3D printing for limited points, the surgeons can observe the U andP points of common type portal vein or variant portal vein 3D and roundly, therefore, to guide the formulation of operation plan and precise operation.

Common type [Figure 1]a: Under this situation, limited point (U point) of left-sided biliary ducts is located on the reverse turn between horizontal part and sagittal part of left branch of portal vein in the right hepatectomy. Limited point (P point) of right-sided biliary ducts is located on the bifurcate portion of portal vein between right anterior branch and right posterior branch.

Type I variation [Figure 1]b: Right-anterior branch, right posterior branch and left branch of portal vein emerge as trifurcation because the trunk of left branch still exists, the U point is determined andP point moves toward portahepatis.

Type II variation [Figure 1]c: The trunk of portal vein branches off right posterior branch first, and in its way upward, it branches off right anterior and left branches. In this situation, P point is determined and U point moves toward portahepatis.

Type III variation [Figure 1]d: The trunk of portal vein divides right posterior branch directly, and right anterior branch originates from the trunk of portal vein left branch. In this situation, P point moves toward to portahepatis.

Thus, when I, II, and III variation happen, U point is fixed, andP point moves toward portahepatis [Figure 4]. In this situation, when hilar cholangiocarcinoma requires right hemihepatectomy, we should isolate the trunk of portal vein, right anterior branch, and left branch, respectively. We then resect the right anterior branch of portal vein when we have protected the trunk and left branch of portal vein. On the other hand, when patients undergo left hemihepatectomy, we should isolate the left branch and right anterior branch of portal vein, and then resect the left branch of portal vein when we have protected the right anterior branch of portal vein. At the same time, based on liver 3D printing and intraoperative pathological examination, we correct the clinical classification of hilar cholangiocarcinoma in real time to select related types of operation.

Figure 4: The P point moves forward in Type II variation of portal vein (a). The Type II variation of portal vein, the P point moving forward displayed by in 3D image (b). The Type II variation of portal vein intraoperatively, and it was the same as the preoperative 3D visualization results. LHA: Left hepatic artery. RA: The right anterior branch of portal vein. RP: The right posterior branch of portal vein. RHA: Right hepatic artery, originating from the superior mesenteric artery

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Recommendation

Before we perform the operations for hilar cholangiocarcinoma, we apply 3D visualization models to differentiate and analyze variety of portal vein variations and to confirm the limited point of hepatectomy, and then formulate different operation plans.

Three-dimensional visualization guides the operation plans of hepatic artery variations

In operations for hilar cholangiocarcinoma, attention should be paid to such anatomical variations as right hepatic arteries originating from superior mesenteric arteries, and common hepatic arteries originating from mesenteric arteries. 3D visualization is able to display a variety of variations of hepatic artery clearly and roundly, avoiding intraoperative damage, which has a great value for preventing postoperative ischemic biliary disease and stenosis of bile ducts in long term.

Recommendation

When using 3D visualization models to display the anatomical variations, we should pay attention to protecting proper hepatic artery originating from superior mesenteric artery; when we isolate the porta hepatis, we should pay attention to protecting those variant hepatic arteries.

Three-dimensional visualization guides the operation plans of hepatic vein variations

As previously reported,^[16] the variation rate of the left hepatic vein is about 26%, that of the middle hepatic vein is about 17.5%, and that of the right hepatic vein is about 39%. The occurrence rate of right inferior-posterior hepatic vein is 21%. The occurrence rate of vein in IV segment is about 51.5%.

Recommendation

Before operation, 3D visualization technology can be used to confirm whether the variations of hepatic vein mentioned above exist or not for patients with hilar cholangiocarcinoma. For patients with hilar cholangiocarcinoma requiring right hemihepatectomy and extended right hemihepatectomy, the presence of IV segment vein is important for blood backflow of residual liver. For patients with hilar cholangiocarcinoma requiring left trisegmentectomy, the presence of right inferior-posterior hepatic vein is significant for blood backflow of residual liver.

3D visualization models display dilated bile ducts and are applied to formulate surgical strategy although MRCP is able to reveal dilated intrahepatic bile ducts and invasion depth of bile ducts in portahepatis, the occurrence of overlapped imaging of bile ducts makes it difficult to display the small dilated bile ducts, especially for bile ducts of residual liver and of caudate lobe. 3Dvisualization models have a significant value for operations to display dilated bile ducts intraoperatively and bilioentreric anastomosis, preventing bile leakage postoperatively.^[17],[18]

Recommendation

3D visualization models and 3D printing models can be used to identify variety kinds of bile duct anatomical features (such as their origins and ends, invasion depth, and variations), predict the number, size, morphology of bile duct stump in residual liver, design rational plans for bile drainage, and confirm the adequate drainage for biliary reconstruction.

Preoperative Three-dimensional Visualization Simulation Operation

The Importing reconstructed 3D model is imported into simulation operation system. According to the spatial relationship between tumor and portal vein, and hepatic artery, using the virtual operation system is used to formulate the circumstances of simulation operation. The using phantom force feed-back system is used to perform various variety kinds of simulation operation for 3D visualization models.

Recommendation

Organizations that, which can afford to this equipment and method, can perform simulation operations according to the classification of hilar cholangiocarcinoma preoperatively to select the optional operation plans and to perform precise operations.

Three-dimensional Visualization for Intraoperative Examinations of Hilar Cholangiocarcinoma Classification

Reconstruction of 3D visualization models requiring requires surgeons in hepatobiliary surgery department who is experienced in analyzing medical imaging to achieve it. Nevertheless, the deviation is unavoidable for reasons such as: the quality of CT imaging data, and artifacts, which can affect the quality of 3D visualization models. Accompanied with Based on intraoperative B-typed ultrasound, and the results of pathological examination result to, reconfirm the consistency of between 3D visualization models and clinical reality can be reconfirmed, and finally decide the ultimate operation plan can be finally decided.^{[19],[20],[21],[22]}

Recommendation

Applying intraoperative B-type ultrasound examination, and intraoperative pathological examination results can be used to justify diagnosis and classification of 3D visualization for hilar cholangiocarcinoma, and it can be revised it if necessary.

Other Comprehensive Therapy Therapies

For patients with V type hilar cholangiocarcinoma which for whom 3D visualization has identified, confirmed that curative resection or pure intra- or extra-hepatic drainage is are unable to achieve, other palliative treatments can be selected according to 3D visualization models to select palliative treatment.^[23]

Recommendation

For patients with V Type V hilar cholangiocarcinoma which for whom 3D visualization has identified, that curative resection is unable to achieve. Be performed, the surgeons can select other treatment methods according to the guidance of 3D visualization biliary models.

The diagnosis and treatment for hilar cholangiocarcinoma is the aporia a challenge in biliary surgery. The application of 3D visualization offers energetic support for precise preoperative diagnosis and precise operation. During the operations, we can combining 3D combine 3D visualization with intraoperative B-type ultrasound examination and intraoperative pathological examination, revise the clinical classification of hilar cholangiocarcinoma in real time, and combing the surgeon's experiences to select optional surgical plan based on surgeon's experiences. For the reason because that many patients with hilar cholangiocarcinoma had liver function damage, therefore, we should pay attention to the protection of liver function (such as administration of ulinastatin),^[24] as well as when giving the surgical therapy.

The committee of expert consensus on precise diagnosis and treatment of hilar cholangiocarcinoma guided by 3D visualization technology:

Validated by Head Judgement: Wan Yee Lau

Directors of the Committee: Shaoxiang Zhang, Hongchi Jiang, Lijian Liang

Participants: Susu Bao, Xiujun Cai, Xiangjun Cai, Yajin Chen, Guihua Chen, Shuqun Cheng, Chaoliu Dai, Chihua Fang, Jia Fan, Xiaoping Geng, Hongchi Jiang, Yi Jiang, Weidong Jia, Dexing Kong, Lijian Liang, Jun Liu, Yingbin Liu, Lianxin Liu, Qiping Lu, Jingfeng Liu, Jinrui Ou, Baogang Peng, Zhiwei Quan, Chengyi Sun, Liguo Tian, Xiaoyu Yin, Yang Yang, Shaoxiang Zhang, Xuewen Zhang, Bixiang Zhang, Taiping Zhang, Weiping Zhou, Xuting Zhi

Byliners: Chihua Fang^1,2, Ning Zeng^1,2, Qiping Lu³

¹Department of Hepatobiliary Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China, ²The Clinical Engineering and Technological Research Center of Digital Medicine of Guangdong Province, Guangzhou 510282, China,³ Department of General Surgery, Wuhan General Hospital of Guangzhou Military, Wuhan 430064, China.

This article is based on a study first reported in the Chin J Prac Surg, 2017(01):48-52.

Financial support and sponsorship

The National High Technology Research and Development Program of China (863 Program) (Grant No. 2006AA02Z346 and 2012AA021105), the National Key R and D Program (No. 2016YFC0106500), the NSFC-GD Union Foundation (No. U1401254), the Major Instrument Project of National Natural Science Fund (No. 81627805), the Natural Science Foundation of Guangdong Province, China (Grant No. 6200171), the Science and Technology Program of Guangdong Province, China (Grant No. 2012A080203013), the Science and Technology Plan Project of Guangzhou (No. 201604020144).

Conflicts of interest

There are no conflicts of interest.

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