In order to provide morphological data and theoretical basis for pig-to-human hepatic xenotransplantation, the difference in morphological parameters and vessel wall structural factors between human and porcine hepatic portal vein was studied. From human subjects and pigs of varying ages, hepatic portal veins were collected, paraffin-embedded and cut into sections. The histological structures were stained with HE, and elastin, collagen and smooth muscles were stained with Weigert, Aniline blue and orange G, respectively. Morphological parameters and relative contents of structural components were determined under microscopy and by computer image analysis system, respectively. The results showed that histological structures of human and porcine hepatic portal vein wall were similar. Caliber, wall thickness, lumen and wall area in pigs increased with age, all in linear correlation to months. Morphological parameters of 6- month-old pigs were similar to those of human. In pigs, collagen content increased gradually with months, elastin content remained relatively stable, smooth muscle content reached the peak at the 3rd month, and collagen/elastin (C/E) rose gradually. The contents of collagen and elastin in porcine hepatic portal vein wall were lower, while the content of smooth muscle was higher than in human, and C/E at the 5th and 6th month was similar to that in human. It is concluded that morphological parameters and contents of structural components of porcine hepatic portal vein vary with age. At the 6 month, its caliber, wall thickness, lumen and wall area are similar to those of human. There are differences in contents of structural components between human and pigs. However, in terms of C/E, mechanic properties of pigs at the 5th and 6th month mimic those of human, hence inosculation is viable in xenotrans-plantation between pigs and human.
Collagen/*analysis ; Elastin/*analysis ; Image Processing, Computer-Assisted ; Liver Transplantation ; Muscle, Smooth, Vascular/cytology ; Portal Vein/*anatomy & histology ; Portal Vein/chemistry ; Swine ; Transplantation, Heterologous

OBJECTIVETo investigate the anatomy of right portal vein based on three-dimensional (3D) visualization technology and provide a morphological basis for computer-assisted individualized liver segmentation and anatomical hepatectomy.

METHODSLiver CT data of 83 cases were segmented and reconstructed using the medical image three-dimensional visualization system (MI-3DVS), and 3D classifications of the right portal vein were established according to its branch number, direction and distribution. Individualized liver segmentation was performed based on the 3D typing results.

RESULTSThe reconstructed portal vein models were capable of visualizing the fourth-order portal branches. Generally, the third-order right portal branches were classified into P5, P6, P7 and P8 branches. According to the 3D distribution of the branches, P5 branches were classified into types A, B, C, D, and E [in 16 (19.3%), 5 (6%), 30 (36.1%), 7(8.5%), and 25 (30.1%) cases, respectively], P8 branches into types A, B, C, and D [in 29 (34.9%), 29 (34.9%), 10 (12.1%), and 15 (18.1%) cases, respectively], P6 branches into types A, B, C, and D [in 35 (42.2%), 12 (14.5%), 33 (39.7%), and 3 (3.6%) cases, respectively], and P7 branches into types A, B, C, D, E, and F [in 27 (32.5%), 11(33.3%), 27 (32.5%), 4(4.8%), 12 (14.5%), and 2 (2.4%) cases, respectively]. Individualized liver segmentation was achieved based on liver segments supplied by the third-order portal branches.

CONCLUSION3D classifications of the complex and highly variant anatomy of third-order right portal vein and individualized liver segmentation based on this classification before the operation facilitates successful performance of anatomical hepatectomy.

Hepatectomy ; methods ; Humans ; Imaging, Three-Dimensional ; Liver ; anatomy & histology ; surgery ; Portal Vein ; anatomy & histology ; Surgery, Computer-Assisted ; Tomography, X-Ray Computed

OBJECTIVETo investigate the risk factors associated with persistent thrombocytopenia after liver transplantation (LT), and to explore effective measures for prevention.

METHODSOne hundred and twenty-eight adult patients, who received liver transplantation in our hospital between January 2009 and June 2012 and met the inclusive criteria, were enrolled in the study. The clinical data were retrospectively analyzed, including pre-LT spleen volume, main portal vein size, coronary vein size, platelet and white blood cell levels, total bilirubin level and model of end stage liver disease score. The risk factors associated with persistent thrombocytopenia after LT were evaluated by logistic regression analysis. The effect of simultaneous splenic artery coarctation for high risk patients was evaluated with χ2 test.

RESULTSLogistic regression analysis showed that per-LT spleen volume larger than 500 ml (P = 0.012, OR=2.789, 95%CI: 1.249-6.227) and portal vein size beyond 15 mm (P = 0.017, OR = 3.124, 95%CI: 1.230-7.933) were independent risk factors for persistent thrombocytopenia after LT. The incidence rate of persistent thrombocytopenia after LT in patients with or without simultaneous splenic artery coarctation were 16.7% (1/6) and 66.7% (32/48), respectively(P < 0.05).

CONCLUSIONSpleen volume larger than 500 ml and portal vein size beyond 15 mm are risk factors for persistent thrombocytopenia after LT. Simultaneous splenic artery coarctation may reduce the occurrence of persistent thrombocytopenia after LT.

Adult ; Humans ; Liver Transplantation ; adverse effects ; Organ Size ; Portal Vein ; anatomy & histology ; Retrospective Studies ; Risk Factors ; Spleen ; anatomy & histology ; Thrombocytopenia ; epidemiology

OBJECTIVETo evaluate subtraction images acquired with 3D true steady-state free-precession(SSFP)sequence combined with time-spatial labeling inversion pulse(T-SLIP)for selective and non-contrast-enhanced(non-CE)visualization of the portal venous system,and explore the optimization of this protocol.

METHODSTotally 13 healthy volunteers were recruited.Respiratory-triggered 3D true SSFP sequences on a 1.5T MRI system combined with T-SLIP placed on the spleen and mesenteric area were performed.The portographic images were generated from the subtraction between the pulse on and off images.According to the difference in inversion time(TI)of T-SLIP,four image groups group A(TI of 1300 ms),group B(TI of 1100 ms),group C(TI of 900 ms)and group D(TI of 700 ms),were assigned and compared to detect the optimal TI for portography.For quantitative analysis,the signal intensity(SI)of left and right liver lobe,the large vessels as main,right and left portal vein(MPV,RPV and LPV,respectively)and small vessels as branches of segments four(P4),six(P6)and eight(P8)were measured.The relative SI of MPV,RPV and LPV,as well as P4,P6 and P8 were also compared.For qualitative evaluation,the quality score of visualization was also evaluated using a 4-point scale.One-Way ANOVA and LSD test were used for comparison of quantitative data,and Friedman signed rank test was used for comparison of qualitative scores.

RESULTSIn 52 sequences of 13 volunteers,the selective visualization of the portal vein was all successfully conducted.Quantitative evaluation showed significant increased SI at the left lobe between C and D groups and A and B groups(comparison of group C to group A and BP=0.004,0.011;comparison of group D to group A and BP=0.001,0.004),while relative SI of LPV of groups C and D were lower than groups A and B(comparison of group C to group A and BP=0.015,0.015;comparison of group D to group A and BP=0.000,0.000).The relative SI of MPV in group D were decreased than groups A(P=0.000),B(P=0.000),and C(P=0.019).There was no significant difference in relative SI of small vessels among four groups(P>0.05).The image score of portal vessels in four groups also showed no differences(P>0.05).

CONCLUSIONS3D true SSFP scan with T-SLIP enabled selective non-CE visualization of the portal vein with digital subtraction method.A fixed TI of both 1300 and 1100 ms can be preferable.

Adult ; Contrast Media ; administration & dosage ; Female ; Humans ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; methods ; Male ; Portal Vein ; anatomy & histology ; Young Adult

OBJECTIVETo investigate the three-dimensional reconstruction methods of the portal vein using 64-slice spiral CT data and the anatomical variation of the portal vein.

METHODSThree-dimensional reconstruction of the portal vein was performed using Mimics software based on the 64-slice spiral CT data of 64 cases. Each model of the portal vein and its branches was evaluated according to the presentation rate, depiction quality and anatomic variation.

RESULTSThe reconstructed model showed a depiction rates of 100% for the 4-grade branches of the portal vein. The stem of the portal vein and the left and right branches of the level III or above were all displayed, but in 2 cases the superior mesenteric vein and in 1 case the spleen vein was displayed only to the level IV. Of the 64 cases, 50 (78.1%) had normal portal vein and 14 (21.9%) showed anatomical variations.

CONCLUSIONThe 3D model vividly mimics the anatomic variations of the portal vein to provide valuable information for surgical plans.

Adult ; Female ; Humans ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; methods ; Male ; Middle Aged ; Portal Vein ; anatomy & histology ; diagnostic imaging ; Tomography, Spiral Computed ; methods ; Young Adult

OBJECTIVETo construct a three-dimensional (3D) liver model of Wuzhishan mini-pig for virtual liver surgeries.

METHODSThe biliary tree and hepatic arteries of Wuzhishan mini-pig were perfused with perchloroethylene and ethyl acetate along mixed with lead oxide, and the hepatic vein and portal vein were perfused with a mixture of dental base acrylic resin and lead oxide. The sectional images were acquired using a 64-slice spiral CT, and the 3D models of the portal vein, hepatic vein, biliary tree, hepatic arteries, and liver parenchyma were reconstructed using Mimics software; the resection image of the liver was also designed. The intrahepatic vascular cast was prepared by corroding the soft tissue with hydrochloric acid.

RESULTS AND CONCLUSIONThe intrahepatic vascular cast obtained fully retained the vascular architecture and displayed the fifth- and sixth-level branches of the hepatic vein and portal vein and the third- and fourth-level branches of the artery and bile duct. The 3D model of liver allowed stereoscopic and accurate display of the third- and fourth-level branches of the hepatic vein and portal vein and the second- and third-level branches of the artery and bile duct. The 3D model showed fewer branches but represented the structural distribution identical to the cast. The 3D model could clearly display the spatial relationship between the vasculature and the soft tissue in virtual resection of the liver tissues, and thus provides a useful model for training of laparoscopic liver resection.

Animals ; Bile Ducts ; Hepatic Artery ; Hepatic Veins ; Imaging, Three-Dimensional ; Liver ; anatomy & histology ; Models, Anatomic ; Portal Vein ; Swine ; Swine, Miniature ; Tomography, Spiral Computed

Unlike volume models, surface models, which are empty three-dimensional images, have small file size, so that they can be displayed, rotated, and modified in a real time. For the reason, the surface models of liver and neighboring structures can be effectively applied to virtual hepatic segmentectomy, virtual laparoscopic cholecystectomy, and so on. The purpose of this research is to present surface models of detailed structures inside and outside the liver, which promote medical simulation systems. Forty-seven chosen structures were liver structures such as portal triad, hepatic vein, and neighboring structures such as the stomach, duodenum, muscles, bones, and skin. The structures were outlined in the serially sectioned images from the Visible Korean Human to prepare segmented images. From the segmented images, serial outlines of each structure were stacked; on the popular commercial software, advanced surface reconstruction technique was applied to build surface model of the structure. A surface model of the liver was divided into eight models of hepatic segments according to distribution of the portal vein. The surface models will be distributed to encourage researchers to develop the various kinds of medical simulation of the abdomen.
Asian Continental Ancestry Group ; Computer Simulation ; Humans ; *Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; Liver/*anatomy & histology ; *Models, Anatomic ; Models, Biological ; Portal Vein/anatomy & histology ; Software ; Tomography, X-Ray Computed

OBJECTIVETo study the imaging characteristics and variations of individual digitized hepatic vein and portal vein which were reconstructed by medical image three-dimensional visualization system (MI-3DVS), assess the value of MI-3DVS assisted hepatectomy.

METHODSFrom June 2008 to September 2012, the clinical data of 81 patients who underwent hepatectomy with the assist of MI-3DVS were retrospectively reviewed. There were 61 male and 20 female patients, and their age were 12-81 years (median 46 years). The patients with malignant tumors were in 69 cases and with benign tumors in 12 cases. The characteristics and variations of individual digitized hepatic vein and portal vein were observed.Omnidirectional rotation of the three-dimensional (3D) model to observe the distribution of intrahepatic venous system as well as the relationship between the tumor and the veins. 3D models were then simulated resection by the Freeform modeling system.

RESULTSOf all the 81 3D models of the patients, greater posterior hepatic veins appeared in 10 (12.3%) cases, segment VI hepatic vein appeared in 34 (41.9%) cases. The portal vein was separted with the left branch and the right branch in the hilar in 64 cases, the portal trunk was divided into the left branch of portal vein, the right anterior portal branches, the right posterior portal branches trifurcated in 10 cases, the branch of right anterior portal vein start from the left trunk and the branch of right posterior portal vein start from the main trunk independently in 6 cases, there was 1 case, lack of left branch of portal vein. 81 patients underwent hepatectomy with the assist of MI-3DVS, minor hepatectomy in 57 cases, major hepatectomy in 24 cases (comparatively-reduced major hepatectomy in 12 cases). R0-resection was achieved in all of the patients. Both the inflow and the outflow were maintained in the residual liver after the completion of hepatectomy. Postoperative liver failure was observed in none of the patients.

CONCLUSIONSMI-3DVS in liver resection was the best choice of surgical approach provides an intuitive basis, and it could reduce the risk of surgery to prevent postoperative hepatic failure.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Hepatectomy ; methods ; Hepatic Veins ; anatomy & histology ; Humans ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Portal Vein ; anatomy & histology ; Retrospective Studies ; Young Adult

OBJECTIVETo study the value of three-dimensional (3D) visualization, 3D printing and 3D laparoscopy (3-3D techniques) in the diagnosis and surgical treatment of hepatic tumors.

METHODSFrom November 2013 to January 2015, 22 patients with hepatic tumors admitted in our department underwent abdominal thin-slice CT scanning. The CT images were imported into Medical Image three Dimensional Visualization System (MI-3DVS) for 3D reconstruction. Standard Template Library (STL) files were exported for 3D printing. The hepatic vascular classification and predicted liver resection were performed with the aid of MI-3DVS system. The 3D models were then printed and virtual liver resections were executed accordingly. Based on these preoperative surgical planning data, we performed anatomical hepatectomy using 3D laparoscopy, and the intraoperative blood loss, volume of virtual and actual liver resection and postoperative hospital stay were recorded.

RESULTSAccording to Michels's classifications, 19 patients had type I, 2 had type II, and 1 had type VIII hepatic arteries; based on Cheng classifications, the portal vein was classified into type I in 17 cases, type II in 2 cases, and type III in 2 cases, and type IV in 1 case; according to Nakamura classifications, the right hemiliver hepatic vein was classified into type I in 10 cases, type II in 7 cases, and type III in 5 cases. In the virtual operations, the mean volume of liver resected was 490 ± 228 ml and the mean remnant liver volume was 885 ± 139 ml, with a remnant to functional liver volume ratio of (71 ± 11)%. The 3D printed models stereoscopically displayed the location of the liver tumors and adjacent liver vascular structure clearly. Laparoscopic hepatectomy was performed successfully in 20 patients guided by the 3-3D techniques, and the other 2 patients required convertion to open hepatectomy. The mean operation time was 186 ± 92 min, the intraoperative blood loss was 284 ± 286 ml, the mean actual liver resection volume was 491 ± 192 ml, and the mean postoperative hospital stay of the patients was 8.6 ± 3.7 days.

CONCLUSIONSThe 3-3D technique can facilitate the evaluation of preoperative risk and critical anatomical structures and navigate the surgical procedure in real time in anatomical hepatectomy for hepatic tumors.

Blood Loss, Surgical ; Hepatectomy ; Hepatic Artery ; anatomy & histology ; Hepatic Veins ; anatomy & histology ; Humans ; Imaging, Three-Dimensional ; Laparoscopy ; Liver Neoplasms ; diagnosis ; surgery ; Portal Vein ; Printing, Three-Dimensional ; Tomography, X-Ray Computed

The shortage of organ donors has stimulated interest in the possibility of using animal organs for transplantation into humans. In addition, pigs are now considered to be the most likely source animals for human xenotransplantation because of their advantages over non-human primates. However, the appropriate standard values for estimations of the liver of micropigs have not been established. The determination of standard values for the micropig liver using multi-detector row computed tomography (MDCT) would help to select a suitable donor for an individual patient, determine the condition of the liver of the micropigs and help predict patient prognosis. Therefore, we determined the standard values for the livers of micropigs using MDCT. The liver parenchyma showed homogenous enhancement and had no space-occupying lesions. The total and right lobe volumes of the liver were 698.57 +/- 47.81 ml and 420.14 +/- 26.70 ml, which are 51.74% and 49.35% of the human liver volume, respectively. In micropigs, the percentage of liver volume to body weight was approximately 2.05%. The diameters of the common hepatic artery and proper hepatic artery were 6.24 +/- 0.20 mm and 4.68 +/- 0.13 mm, respectively. The hepatic vascular system of the micropigs was similar to that of humans, except for the variation in the length of the proper hepatic artery. In addition, the diameter of the portal vein was 11.27 +/- 0.38 mm. In conclusion, imaging evaluation using the MDCT was a reliable method for liver evaluation and its vascular anatomy for xenotransplantation using micropigs.
Animals ; Female ; Hepatic Artery/anatomy & histology ; Humans ; Imaging, Three-Dimensional/methods/*veterinary ; Liver/*anatomy & histology/blood supply ; Liver Transplantation/*methods ; Living Donors ; Male ; Portal Vein/anatomy & histology ; Swine ; Swine, Miniature/*anatomy & histology ; Tomography, X-Ray Computed/methods/*veterinary ; Transplantation, Heterologous/*methods