Research progress in liver transplantation in patients with situs inversus totalis / 器官移植

Situs inversus totalis (SIT) is a rare congenital condition, with an extremely low incidence. There is no difference between SIT individuals without onset of diseases and healthy counterparts. However, when SIT individuals suffer from diseases, the diagnosis and treatment are highly challenging due to insufficient understanding of SIT populations, especially for those complicated with end-stage liver disease and requiring liver transplantation. It is a huge challenge for surgeons whether SIT individuals serve as donors or recipients of liver transplantation. In this article, recent case reports related to liver transplantation in SIT patients were summarized, and the development, key procedures, clinical prognosis and postoperative complications of liver transplantation in SIT patients were reviewed.

A brief discussion of Glisson pedic-first approach in laparoscopic anatomical hepatectomy / 中华肝胆外科杂志

With the continuous in-depth understanding of liver anatomy and the progress of surgical techniques, laparoscopic hepatectomy has been developed rapidly, especially the laparoscopic anatomic hepatectomy has become the most commonly surgical method. The dissection and treatment of liver Glisson pedicle is the core techniques of laparoscopic anatomic hepatectomy. The Glisson hepatic pedicle approach has been widely used in open and laparoscopic anatomical hepatectomy, especially in laparoscopic hepatectomy. The possible advantages over the traditional approach are still under debate, and there is no standard surgical approach for pedicle dissection to date. This article introduces Glisson pedicle approach and the advantages and clinical application of laparoscopic anatomical hepatectomy with Glisson pedicle approach.

Anatomy of the liver (a05.8. 01. 001): worldwide review, 2019: new findings, concepts and definitions support a division of the liver into seven portal segments / Anatomía del hígado (a05. 8.01. 001): revisión mundial, 2019: nuevos hallazgos, conceptos y definiciones respaldan una división del hígado en siete segmentos portales

Due to a lack of consensus on the description of the human liver anatomy, we decided to explore different researches worldwide. Studies are focused on the hepatic vascularization. The results obtained through serial dissections in embryos, fetuses and adults have contributed to new definitions. Researchers around the world have agreed on finding the bases to propose a liver segmentation with seven portal segments.

La confusión existente en la descripción de la anatomía del hígado humano nos llevó a realizar esta revisión a nivel mundial. Las investigaciones se centran en la vascularización del hígado, el conocimiento obtenido mediante disecciones seriadas en embriones, fetos y adultos han aportado nuevos conocimientos que fundamentan nuevas definiciones. Investigadores de países distantes han coincidido en encontrar las bases para proponer una segmentación del hígado con siete segmentos portales.

Can we delineate preoperatively the right and ventral margins of caudate lobe of the liver?

PURPOSE: Complete removal of the caudate lobe, which is sometimes necessary, is accomplished via isolated caudate lobectomy or hepatectomy that includes the caudate lobe. It is impossible, however, to confirm the right and ventral margins of the caudate lobe by preoperative imaging. This study was undertaken to determine whether we could identify the right and ventral margins of the caudate lobe preoperatively using Synapse 3D visualization software. METHODS: Ninety-four preoperative 3-dimensional (3D) computed tomographic images (1-mm slices) of the liver from candidate donors were examined. The images of the caudate lobe were subjected to a counter-staining method according to Synapse 3D to delineate their dimensions. We first examined whether the right margin of the caudate lobe exceeded the plane formed by the root of the right hepatic vein (RHV) and the right side of the inferior vena cava (IVC). Second, we determined whether the ventral margin of the caudate lobe exceeded the plane formed by the root of the middle hepatic vein (MHV) and the root of the RHV. RESULTS: For the right margin, 17 cases (18%) exceeded the RHV-IVC plane by a mean of 10.2 mm (range, 2.4–27.2 mm). For the ventral margin, 28 cases (30%) exceeded the MHV-RHV plane by a mean of 17.4 mm (range, 1.2–49.1 mm). CONCLUSION: Evaluating the anatomy of caudate lobe using Synapse 3D preoperatively could be helpful for more precise anatomical resection of the caudate lobe.

Anatomical Variation of the Glissonean Pedicle of the Right Liver

PURPOSE: Many studies have been conducted to date regarding whether the right hepatic vein is the accurate border that divides the anterior and posterior section of the right liver. It has been reported that the Glisson pedicle of the right liver may be an anatomical variation that does not have a consistent morphology. We analyzed the relationship between the true borders of the anterior and posterior sections, and the right hepatic vein, based on cadaver dissection and MD-CT image analysis of the anatomical variation of the Glisson pedicle of the right liver. METHODS: Sixteen cadaver livers were available for dissection from the Department of Anatomy, and pre-operative MD-CTs of 20 donor livers who underwent living donor liver transplantation prior to December 2009, were obtained. We analyzed the 3D-relationship between the branches of the Glisson pedicles and the right hepatic vein of the right liver. They were divided into 3 groups according to the sliding pattern of the branches of the Glisson pedicle origin. When all segmental branches of the anterior pedicle arise from the main trunk of the anterior pedicle and all branches of posterior pedicle arise from the main trunk of posterior pedicle, it was designated as Group A (Normal Group). When a portion of the segmental branches of the anterior pedicle arises from the main trunk of the posterior pedicle, it was designated as Group B (Posterior dominant group). When a portion of the branches of the posterior pedicle arises from the main trunk of the anterior pedicle, it was designated as Group C (Anterior dominant group). RESULTS: Among the 16 cadaver liver dissections, 6 cases were in Group A, 5 in Group B, and 3 in Group C. Two cases were excluded from the study because the inferior right hepatic vein was the main draining vein of the right liver. The analysis of preoperative MD-CT of the 20 donor livers showed that there were 13, 4, and 3 patients in Groups A, B, and C, respectively. CONCLUSION: According to Couinaud's theory of anatomy, the right hepatic vein serves as the border between the anterior and posterior sections of the right liver. But, due to the frequent anatomical variations, an adequate understanding of the anatomical variations of the right Glisson pedicle should be necessary for liver surgery.

Establishment of mouse liver regeneration model by consecutive partial hepatectomy / 第二军医大学学报

Objective:To establish a quantifiable and easily manipulable mouse model of liver regeneration by partial hepateetomy, so as to provide a basis for investigating the underlying cellular and molecular mechanisms and pathophysiological significance of liver regeneration. Methods: Normal adult CS 7BL/ 6 mice were fixed by cardiac perfusion, the liver lobes were dissected and weighed, and the prupurtiuns uf each lube were calculated. Under anesthetic and sterile condition, partial hepatectomy was performed by removing the left lateral, left middle,and right middle liver lobes in turn to establish the regeneration model. The activation of alpha-fetoprotein (AFP) gene in the regenerating liver was dynamically monitored by real-time PCR analysis. Results: The left lateral, left ddle,and right middle liver lobes together accounted for approximately 70% of the total liver weight. The animals survived and lived well after removal of the three lobes in turn. RT PCR showed that AFF expression was activated in the regenerating livers. Conclusion: We have successfully established the mouse model of liver regeneration by consecutive partial hepatectomy. This method can quantify the heptectomy and is easy to perform,which lays a foundation for studying liver regeneration in mice.

Avaliação de variáveis potencialmente preditivas de má evolução da recidiva da hepatite C em pacientes submetidos a transplante de fígado, com ênfase nos achados anátomo-patológicos / Evaluation of potentially predictive findings of poor outcome in recurrent chronic hepatitis C after liver transplantation, with emphasis on histopathological parameters

Introdução: Hepatite crônica recidivada (HCR) é a regra após o transplante hepático (TH) em pacientes infectados pelo vírus da hepatite C (VHC), provocando progressão de fibrose mais acelerada no órgão transplantado do que no fígado nativo. Vários estudos têm apontado que, dentre os pacientes transplantados por doença terminal relacionada ao VHC, há padrões distintos de evolução pós-transplante, influenciados por diversos aspectos clínicos, demográficos, laboratoriais e histopatológicos. Objetivos: Identificar alterações precoces associadas à gravidade da doença recidivada, com ênfase nos achados histopatológicos no TH e nas biópsias de seguimento. Métodos: Foi avaliada uma coorte retrospectiva de 41 pacientes que se submeteram a TH entre 1992 e 2004. Dados clínicos foram recuperados dos prontuários médicos e todas as biópsias de fígado foram reavaliadas. Foram estudadas em especial a primeira biópsia após o primeiro mês (PAT) e a primeira biópsia com diagnóstico de hepatite crônica (PHC) de cada paciente. Estas duas biópsias foram também submetidas ao estudo das células estreladas hepáticas através da marcação por -actina de músculo liso. A presença de esteatose e dos parâmetros de hepatite crônica foi quantificada em todas as biópsias dentro dos diferentes períodos do pós-transplante. Resultados: A idade média no transplante foi de 51 anos, com 72% dos pacientes do sexo masculino. O tempo médio de seguimento histopatológico (tempo entre o transplante e a última biópsia hepática realizada) foi de 2234 dias (785-4640). A taxa global anual de progressão de fibrose (TPF) foi de 0,62 (escore de Ishak), a partir da qual os pacientes foram classificados no grupo de fibrosadores rápidos (FR),quando TPF > 0,62, e no grupo de fibrosadores lentos (FL),quando TPF <0,62.O tempo para o diagnóstico histopatológico de HCR, os fatores ligados ao doador e os achados histopatológicos precoces associados ao diagnóstico de hepatite crônica não se apresentaram diferentes...

Background: Recurrent chronic hepatitis (RCH) is the rule after liver transplantation (LT) in hepatitis C virus (HCV) infected patients, with a faster fibrosis progression in allograft than in native liver. Many studies have pointed out that, even in the group of patients transplanted for HCV end-stage disease, there are distinct outcomes due to the influence of several clinical, demographic, laboratorial and histopathological factors. Objectives: Evaluate earlier changes that could be associated to severity of disease recurrence, with emphasis on histopathological findings at LT and follow up biopsies. Method: A retrospective cohort of forty one HCV infected patients who underwent LT between 1992 and 2004 was studied. Clinical data were recovered from hospital files and all liver tissue specimens were reviewed. The first liver biopsy after first month post-LT (FAF) and the first biopsy with chronic hepatitis (FCH) were considered to each patient. Expression of -smooth muscle actin in hepatic stellate cells by immunohistochemistry was also examined in these biopsies. Additionally, steatosis and chronic hepatitis parameters were quantified in all biopsies in each period after LT. Results: The mean age at LT was 51 yr; 72% were male; the median histological follow-up (time between LT and last liver biopsy) was 2234 days (785-4640) and the overall annual rate of fibrosis progression (RFP)was 0.62 (Ishak s score). Patients were classified in fast fibrosers (FF)when RFP>0.62,and when RFP<0.62.Time to histopathological diagnosis of RCH, early histopathological changes related to chronic hepatitis diagnosis and donor factors were not significantly different between both groups. Acute cellular rejection was more prevalent in SF (p=0.043), although FF presented significantly higher number of episodes than SF (p=0.036). It was observed an increase in BMI on FF and an decrease in BMI on SF between transplantation and the time of last liver biopsy (p=0.049)...

Hepatic Vein Reconstruction for Living Donor Liver Transplantation using a Modified Right lobe Graft: Experience at Asan Medical Center and focused on Middle Hepatic Vein Reconstruction

Living donor liver transplantation is now widely accepted as a therapeutic option for adult patients suffering with various end-stage liver diseases. The major concerns for use of a right lobe (RL) graft have focused on the safety for the donor and the necessity for including the middle hepatic vein (MHV) into the graft to avoid congestion of the right anterior segment. There are 5 types of RL grafts (simple RL, modified RL, modified extended RL, extended RL with V4b preservation and extended RL), and the selection is usually determined after consideration of the graft size to the recipient, the availability of a vessel graft, the amount of hepatic venous congestion and the reconstruction technique. Various kinds of vessel grafts have been used in practice: 1) greater saphenous vein, paraumbilical vein, portal vein and internal jugular vein from the recipient, 2) various veins and arteries from the deceased donors and 3) bovine pericardium and synthetic vessels. Interposition of a vessel graft is the basic principle for MHV reconstruction. Triphasic liver computed tomography and Doppler ultrasonography are the most useful tools for posttransplant follow-up. When outflow obstruction occurs at the interposed vessel grafts that replace the MHV trunk, then radiological intervention with metallic stent insertion seems to be a feasible and reliable treatment modality. At Asan Medical Center, 200 cases of adult living donor liver transplantation using a modified RL graft revealed a > 90% 2-week patency rate regardless of the types of vessel grafts. In conclusion, it is recommended to make the MHV reconstruction resemble the original configuration of the donor's MHV trunk according to the hemodynamic principles.

Analysis of the Hepatic Segments on the Isotropic Multi-planar Reformatted CT Images

PURPOSE: We wanted to evaluate the diverse distribution and relation of the hepatic segments, as divided by the portal venous territories, on the isotropic multi-planar reformatted (MPR) CT images and we wanted to find their correlation to the intrahepatic venous structures. MATERIALS AND METHODS: Fifty adult patients who underwent portal phase CT images and who had the normal liver contours at CT were included in our study. The portal phase images were obtained with a slice collimation and reconstruction interval of 1.25 mm, and they were reformatted in the coronal and sagittal planes with a slab thickness of 3 mm. For analysis of these MPR images, various terms were newly defined according to the portal venous territories (e.g., three vertical planes [right, middle and left] and one transverse plane and their plane angles, the transverse and longitudinal angles). Also, the dominant segments of the right lobe were newly divided into the S7- and S8-dominant types by comparing the transverse angles. The imaging analysis was then conducted for the following: (1) the diversity of the three vertical planes and the one transverse plane and their plane angles, (2) the proportion of the dominant segments of the right lobe and their relation with the plane angles, and (3) the correlation between the dominant segments and the intrahepatic venous structures. RESULTS: The number of the S7- and the S8-dominant types was 21 and 29, respectively. The vertical and transverse planes were undulating and diverse according to the dominant segments as follows: the plane angles of the right vertical and middle vertical planes were more vertical in the S7-dominant type than in the S8-dominant type (p < 0.001). The right transverse plane angle was more horizontal in the S8-dominant type (p < 0.05). The left transverse plane angle seemed to be rather vertical than horizontal. For the intrahepatic venous structures, despite of our limited data, the anomalous intrahepatic venous structures might have some correlation with the dominant segments. CONCLUSION: According to our results, we suggest that the isotropic MPR images could successfully depict the vertical and transverse planes of the real hepatic segments, as divided by the portal venous territories, which were diverse according to their dominant types.

Safety of 'Isolated IVb (Inferior) Resection of the Liver' by Cadaver Dissection

PURPOSE: Healey divided segment IV of the live as the 'superior portion (IVa) ' and the 'inferior portion (IVb) '. On the contrary, Couinaud suggested that there was no useful purpose in dividing segment IV because of several reasons. Our goal is to evaluate the safety of the 'isolated IVb (inferior) resection of the liver' via performing the dissection of cadavers. METHODS: There were ten total cadavers. Cadaver dissection proceeded with respect to the Glissonian pedicle, the portal vein and the bile duct, respectively. The total number of Glissonian pedicles at segment IV was measured. The distance between the origins of the IVa and IVb branches was measured. Additional pedicles that were known to exist at segment IVa were also evaluated. RESULTS: The mean number of Glissonian pedicles in segment IV, IVa, and IVb was 5 (+/-1.3), 1.6 (+/-7), and 3.4 (+/-0.9), respectively. The mean distance between the origins of the IVa and IVb branches was 5.6 mm (+/-3.9 mm). Two of 10 cases had a very short distance between the origins that were considered as having common origin. Additional pedicles were identified at the Lt. main Glissonian pedicle in all the cases (8 cases: 1 each, 2 cases: 2 each). CONCLUSION: Considering the possible existence of a common origin of segment IVa and IVb Glissonian pedicles, there is the risk that the segment IVa will be injured during 'iso lated IVb resection'. Inevitable ligation of the additional pedicle of segment IVa from the Lt. main Glissonian pedicle can be made during the 'isolated IVb resection'. Therefore, we think that 'isolated IVb resection of the liver' can be safe only when the surgeon divides the branches of segment IVb with meticulous preservation of the IVa branches.

Surgical Anatomy of Left Lobe of the Liver (Couinaud's and Healey's Anatomy) through Korean Cadaver Liver Dissection

PURPOSE: Couinaud described segment IV as being equivalent to segments II and III, as the umbilical portion of the portal vein (PV), and its equal branch of segment II, originated from the transverse portion of the PV. On the contrary, Healey suggested the presence of left lateral and medial segments, on the basis of umbilical fissure. Recently, some author have claimed the branch of segment II originated from the distal portion of the ligamentum venosum (LV), and that this branch was not equal to, only a branch of, the umbilical portion. Our goal was to evaluate the surgical anatomy of the left lobe of the liver through dissecting Korean cadavers. METHODS: The number of cadavers dissected totaled 10. PV, its branches, and the LV were dissected and the length of the transverse portion measured. The distance between the origin of the transverse portion and that of the segment II branch were also measured. RESULTS: The branch of segment II originated from the distal portion of the LV in all 10 cases. The length of the transverse portion was 18.8+/-5.8 mm, and the distance between the origins of the LV and segment II branch was 7.0+/-3.1 mm. CONCLUSION: Considering the embryology of the liver, as well as the above result, the umbilical portion and segment II branch were not equal anatomic structures. The umbilical portion and LV are equal anatomic structures. The branch of segment II is only one of the branches of the umbilical portion. We think Healey's classification is more accurate for the left lobe of the liver.

A feasibility study of laparoscopic liver resections / 中国微创外科杂志

Objective To evaluate the feasibility of laparoscopic liver resection. Methods Total laparoscopic liver resections were carried out in 44 candidates between July 2002 and February 2004, including 22 cases of primary hepatocellular carcinoma, 10 cases of liver hemangioma, 3 cases of liver abscess, 1 case of infected liver cyst, 3 cases of liver focal nodular hyperplasia, 1 case of hepatic adenoma, 1 case of bile duct cystadenoma, 1 case of liver inflammatory granuloma, 1 case of hilar bile duct carcinoma and 1 case of highly specialized biliary cellular carcinoma. According to the Child-Pugh classification, 38 cases fell into “Class A” and 6 cases (all of which were hepatic carcinoma), “Class B”. Results Laparoscopic procedures were completed smoothly, including liver partial resections in 17 cases, left liver anatomical resections in 14 cases and right liver anatomical resections in 13 cases. The operation time was 15～450 min(mean,195 min). The blood loss was 50～1 500 ml (mean, 405 ml). The amount of blood transfusion was 0～1 000 ml(mean,175 ml). Postoperative convalescence was uneventfully, with a hospital stay of 2～9 d(mean,5 6 d). Conclusions Laparoscopic liver resection is a safe and feasible procedure. It may be reserved for both benign and malignant tumors in selected cases.

Laparoscopic liver resection: Report of 16 cases / 中国微创外科杂志

Objective To evaluate the anatomical basis and techniques in laparoscopic liver resections. Methods Entered the study there were 16 patients with both their lesions located at liver margin, or the surface of the right liver, or left liver and their liver functions classified as Child B or above, including 8 cases of primary liver cancer, 3 cases of liver hemangioma, 1 case of cholangiocarcinama, 1 case of hepatic adenoma, 1 case of focal nodular hyperplasia, 1 case of liver abscess and 1 case of infected liver cyst. The procedures were performed, via 4～6 epigastric ports, by using electriccautery, ultracision or endo-cutter for transecting liver and by titanic clip or medical albumin glue for dealing with the cut surface. Results Laparoscopic liver resection was completed under pneumoperitoneum in 16 cases (18 lesions), including 8 cases of local liver resection and 8 cases of anatomical left liver resection. The operation time was (206?75) min and the blood loss was (354?282) ml. An intraoperative blood transfusion of 800 ml was required in 2 cases because of a blood loss of 1000 ml. The abdominal drains were left for (2～4) days and no bile leakage, bleeding or other complications happened. The postoperative hospital stay was (5.8?1.6) days. Conclusions Proper dealing with hepatic portal vessels is the key to the laparoscopic liver resection. In order to effectively control the bleeding during the partial hepatectomy or left hemihepatectomy, it is crucial to fully dissect the sub-grade hepatic portal vessels.

Hilar plate and hepatic vein in cirrhosis: Anatomy and clinical application / 中国微创外科杂志

Objective To study the application of the selective regional anemia hepatectomy. Methods The hepatic veins and hilar plates of 5 liver samples of posthepatitic cirrhosis were measured. Results Out of the 5 samples, the average width and depth of the left branch of hilar plate were 1.78cm and 0.82cm, of the left medial branch were 1.04cm and 1.02cm, of the left lateral superior branch were 0.96cm and 0.74cm, of the left lateral inferior branch were 1.02cm and 0.76cm, of the right branch were 2.02 cm and 1.28cm, of the right posterior branch were 1.20cm and 1.10cm, and of the right anterior branch, 1.22cm and 1.16cm. The average width and depth of the left hepatic vein were 0.82cm and 0.74cm, of the right hepatic vein were 1.16cm and 1.04cm, and of the middle hepatic vein, 0.92cm and 1.18cm. The regional anemia hepatectomy was performed successfully in 2 cases. Conclusions Selective occlusion of the blood flow in and out the hepatic segment or lobe may contribute to a safe and reliable hepatectomy.

Intrahepatic Venous Anato my on Three-Dimensional Spiral CT during Arterial Portography

PURPOSE: To evaluate the intrahepatic anatomy of the hepatic vein and right portal venous system, as seen on 3-D CTAP, and to assess the avascular zone between the anterior and posterior segments of the right lobe in relation to the right hepatic vein. MATERIALS AND METHODS: Fifteen patients in whom nodular hepatocellular was suspected underwent spiral C-TAP. 3-D images of the portal and hepatic vein were obtained using the maximal intensity projection technique. We examined the portal venous branching pattern and the draining pattern of the hepatic venous system to the inferior vena cava, as well as variation of the right hepatic vein and the avascular zone between the anterior and posterior segments of the right lobe. RESULTS: In 13 patients, three hepatic veins were clearly visualized, and in ten, the middle and left hepatic veins conjoined before draining to the IVC. In three patients, three hepatic veins drained separately into the IVC. Two right hepatic veins were seen in three patients. The right portal venous system was clearly visualized in 13 patients a classical branching pattern in 11, trifurcation in one, and four simultaneous branching patterns in one. Lateral projection showed that the angle of the avascular zone declined posteriorly by 26 degree - 64 degree ( 47.5 degree) in relation to the right hepatic vein. CONCLUSION: We observed the drainage pattern of the hepatic vein and variation of the right portal venous system on 3-D image, and confirmed that since the avascular zone declined posteriorly, the right hepatic vein is an inappropriate landmark for right hepatic segmentation.

Intrahepatic Venous Anato my on Three-Dimensional Spiral CT during Arterial Portography

PURPOSE: To evaluate the intrahepatic anatomy of the hepatic vein and right portal venous system, as seen on 3-D CTAP, and to assess the avascular zone between the anterior and posterior segments of the right lobe in relation to the right hepatic vein. MATERIALS AND METHODS: Fifteen patients in whom nodular hepatocellular was suspected underwent spiral C-TAP. 3-D images of the portal and hepatic vein were obtained using the maximal intensity projection technique. We examined the portal venous branching pattern and the draining pattern of the hepatic venous system to the inferior vena cava, as well as variation of the right hepatic vein and the avascular zone between the anterior and posterior segments of the right lobe. RESULTS: In 13 patients, three hepatic veins were clearly visualized, and in ten, the middle and left hepatic veins conjoined before draining to the IVC. In three patients, three hepatic veins drained separately into the IVC. Two right hepatic veins were seen in three patients. The right portal venous system was clearly visualized in 13 patients a classical branching pattern in 11, trifurcation in one, and four simultaneous branching patterns in one. Lateral projection showed that the angle of the avascular zone declined posteriorly by 26 degree - 64 degree ( 47.5 degree) in relation to the right hepatic vein. CONCLUSION: We observed the drainage pattern of the hepatic vein and variation of the right portal venous system on 3-D image, and confirmed that since the avascular zone declined posteriorly, the right hepatic vein is an inappropriate landmark for right hepatic segmentation.

Portal Venous Anatomy in Right Lobe of the Liver: CT Evaluation

PURPOSE: To evaluate the portal venous anatomy in the right lobe of the liver, focusing particularly on the location and size of the anterior and posterior segmental branches of the portal vein and the relationship of the right subdiaphragmatic peripheral portal vein to the right hepatic vein. MATERIALS AND METHODS: From June 1995 to December 1995, 100 spiral CT scan which showed no abnormal findings in the hepatic area were retrospectively analysed. Portal dominant phase images were obtained after the administration of contrast media, with a delay of 60-65 seconds (100 - 120ml, 2-3ml/sec injection rate), slice thickness 10 mm and table speed 10mm/sec. On spiral CT scans, we assessed the location and size of the right portal vein and its branches and also observed the relationship of this vein to the right hepatic vein. RESULTS: In all patients, the right portal trunk divided into anterior and posterior branches. The anterior segmental portal vein was located cephalad to the posterior segment in 81 cases (81%), at the same level in 17 (17%), and caudad in two (2%). Its diameter was greater (>2mm)than that of its posterior segment in 33 cases (33%), smaller in three (3%), and similar in 64 (64%). In 95 cases, the right anterior segmetal portal vein which was directed posteriorly, supplied the subdiaphragmatic portion of segment 7. CONCLUSION: In 81% of cases, the position of the anterior segmental portal vein cephalad, and in 64%of cases it was similar in size to the posterior portal vein. In almost all cases, the subdiaphragmatic portion of segment 7 was supplied by the portal vein from segment 8. Therefore, the right hepatic vein is not in all cases an adequate landmark for dividing Couinaud segments 7 and 8 in the subdiaphragmatic portion.

Portal Venous Anatomy in Right Lobe of the Liver: CT Evaluation

PURPOSE: To evaluate the portal venous anatomy in the right lobe of the liver, focusing particularly on the location and size of the anterior and posterior segmental branches of the portal vein and the relationship of the right subdiaphragmatic peripheral portal vein to the right hepatic vein. MATERIALS AND METHODS: From June 1995 to December 1995, 100 spiral CT scan which showed no abnormal findings in the hepatic area were retrospectively analysed. Portal dominant phase images were obtained after the administration of contrast media, with a delay of 60-65 seconds (100 - 120ml, 2-3ml/sec injection rate), slice thickness 10 mm and table speed 10mm/sec. On spiral CT scans, we assessed the location and size of the right portal vein and its branches and also observed the relationship of this vein to the right hepatic vein. RESULTS: In all patients, the right portal trunk divided into anterior and posterior branches. The anterior segmental portal vein was located cephalad to the posterior segment in 81 cases (81%), at the same level in 17 (17%), and caudad in two (2%). Its diameter was greater (>2mm)than that of its posterior segment in 33 cases (33%), smaller in three (3%), and similar in 64 (64%). In 95 cases, the right anterior segmetal portal vein which was directed posteriorly, supplied the subdiaphragmatic portion of segment 7. CONCLUSION: In 81% of cases, the position of the anterior segmental portal vein cephalad, and in 64%of cases it was similar in size to the posterior portal vein. In almost all cases, the subdiaphragmatic portion of segment 7 was supplied by the portal vein from segment 8. Therefore, the right hepatic vein is not in all cases an adequate landmark for dividing Couinaud segments 7 and 8 in the subdiaphragmatic portion.

Nontumorous Focal Low Attenuated Areas in the Left Lobe around the Falciform Ligament on Contrast Enhanced CTScan: MR Correlation

PURPOSE: To characterize the MR findings of nontumorous focal low attenuated areas around the falciformligament on contrast enhanced CT scan. MATERIALS AND METHODS: MR was used to study twelve patients who oncontrast-enhanced CT scan showed focal low attenuated areas around the falciform ligament. Imaging was carried outwith T1, FSE-T2, fat-suppressed T1, and fat-suppressed FSE T2-weighted pulse sequences at 1.5 T. Dynamic fastlow-angle shot(FLASH) imaging was performed in seven patients and chemical shift images were obtained in five. The findings on contrast enhanced CT scan were compared with those on MR. RESULTS: In five cases, the lesions were slightly hyperintense on T1 and FSE T2-weighted images, hypointense on fat-suppressed images, hyperintense on in-phase image, and presented a considerably diminished signal intensity on opposed-image. Focal hypointensity areas were visualized at 50-75 sec after contrast enhancement in three cases in which a lesion was not depicted oneither T1-or FSE T2-weighted images. CONCLUSION: Nontumorous focal low attenuated areas around the falciformligament were shown on MR imaging as focal fatty infiltrations or pseudolesions.