Congenital Riedel's lobe of the liver: A case report.

Riedel's lobe of the liver is a rare anatomical variant often incidentally found on imaging or through the presence of hepatomegaly on physical examination. While patients are usually asymptomatic, the presentation of this condition can vary, ranging from nonspecific symptoms to more severe issues such as torsion, obstruction, rupture, and bleeding. We present a case of a patient with asymptomatic hepatomegaly who was incidentally found to have Riedel's lobe of the liver, accompanied by an elevated IgG mitochondrial antibody. The range of symptoms associated with this rare anatomical variation underscores its importance in diagnosis and surveillance within this patient population.

The Role of Three-Dimensional Modeling to Improve Comprehension of Liver Anatomy and Tumor Characteristics for Medical Students and Surgical Residents.

OBJECTIVE: Studying liver anatomy can be challenging for medical students and surgical residents due to its complexity. Three-dimensional visualization technology (3DVT) allows for a clearer and more precise view of liver anatomy. We sought to assess how 3DVT can assist students and surgical residents comprehend liver anatomy. DESIGN: Data from 5 patients who underwent liver resection for malignancy at our institution between September 2020 and April 2022 were retrospectively reviewed and selected following consensus among the investigators. Participants were required to complete an online survey to investigate their understanding of tumor characteristics and vascular variations based on patients' computed tomography (CT) and 3DVT. SETTING: The study was carried out at the General and Hepato-Biliary Surgery Department of the University of Verona. PARTICIPANTS: Among 32 participants, 13 (40.6%) were medical students, and 19 (59.4%) were surgical residents. RESULTS: Among 5 patients with intrahepatic lesions, 4 patients (80.0%) had at least 1 vascular variation. Participants identified number and location of lesions more correctly when evaluating the 3DVT (84.6% and 80.9%, respectively) compared with CT scans (61.1% and 64.8%, respectively) (both p ≤ 0.001). The identification of any vascular variations was more challenging using the CT scans, with only 50.6% of correct answers compared with 3DVT (72.2%) (p < 0.001). Compared with CT scans, 3DVT led to a 23.5%, 16.1%, and 21.6% increase in the correct definition of number and location of lesions, and vascular variations, respectively. 3DVT allowed for a decrease of 50.8 seconds (95% CI 23.6-78.0) in the time needed to answer the questions. All participants agreed on the usefulness of 3DVT in hepatobiliary surgery. CONCLUSIONS: The 3DVT facilitated a more precise preoperative understanding of liver anatomy, tumor location and characteristics.

Intrahepatic and anterior course of the inferior vena cava: CT image and 3D reconstruction of a rare anatomical variation.

The widespread use of computed tomography (CT) for diagnosing and screening abdominal conditions often reveals rare, asymptomatic anomalies. There is a wide range of documented congenital variations in the anatomy of the inferior vena cava (IVC) and hepatic veins. In this report, we detail an exceptionally unusual variant of the IVC that follows a frontward and intraliver course, terminating at the anterior section of the right atrium. To gain a deeper insight into this anomaly, we employed 3D reconstruction techniques using the software Slicer and Blender.

Aberrant Right and Left Gastric Veins as a Cause of Hepatic Pseudolesions: A Report of Three Cases.

The complex structure of the liver and its elaborate hemodynamics can cause hepatic pseudolesions on contrast-enhanced imaging, making the interpretation of diagnostic liver imaging challenging. Aberrant gastric veins are rare; most of their epidemiology data comes from small single-center studies. While current literature suggests that pseudolesions originating from aberrant gastric veins mainly present as hyperdense defects, some cases can also show up as hypodense, as shown in these cases. Differences in flow rates between the portal and aberrant veins and the timing of the scans could explain this contradiction. Identifying aberrant gastric veins on cross-sectional imaging is crucial because they could be misdiagnosed as liver lesions, granting further unnecessary workups or invasive procedures. Aberrant gastric veins can also act as pathways for the spread of gastric cancer. This manuscript presents one aberrant right gastric vein and two aberrant left gastric veins causing hepatic pseudolesions.

Effectiveness of using 2D atlas and 3D PDF as a teaching tool in anatomy lectures in initial learners: a randomized controlled trial in a medical school.

BACKGROUND: Anatomy is a crucial part of medical education, and there have been attempts to improve this field by utilizing various methods. With the advancement of technology, three-dimensional (3D) materials have gained popularity and become a matter of debate about their effectiveness compared to two-dimensional (2D) sources. This research aims to analyze the effectiveness of 3D PDFs compared to 2D atlases. METHODS: This study is a randomized controlled trial involving 87 Year-1 and Year-2 medical students at Gazi University Faculty of Medicine, Turkey. The study was conducted in two steps. In Step-1, students were randomized to watch lecture videos on liver anatomy and male genitalia anatomy supplemented with either a 3D PDF (intervention group) or 2D atlas (control group) images. Following the video lectures, a test (immediate test) was administered. In Step-2, the same test (delayed test) was administered 10 days after the immediate test. The test scores were compared between the intervention and control groups. In addition to the descriptive analyses, Chi-square and Mann-Whitney U tests were performed. RESULTS: In the immediate test, while there was no significant difference between the groups for the liver test (p > 0.05), 3D PDF group's scores (Median = 24.50) was significantly higher than the 2D atlas group's in the genitalia test (Median = 21.00), (p = 0.017). The effect size (Cohen's d) was 0.57. In the delayed test, there was no significant difference between the groups in the liver and genitalia tests (p > 0.05). However, the effect size in the immediate genitalia test was 0.40. Year-1 students' immediate test of genitalia performances were significantly higher in the 3D PDF group (Median = 24.00) than the 2D atlas group (Median = 19.00), (p = 0.016). The effect size was 0.76. Also, Year-1 students' 3D PDF group (Median = 20.50) presented with significantly higher performance than the 2D atlas group (Median = 12.00), (p = 0.044) in the delayed test of genitalia, with the 0.63 effect size. CONCLUSION: 3D PDF is more effective than 2D atlases in teaching anatomy, especially to initial learners. It is particularly useful for teaching complex anatomical structures, such as male genitalia, compared to the liver. Hence, it may be a valuable tool for medical teachers to utilize during lectures.

Liver Anatomy 2.0 Quiz: Test Your Knowledge.

The liver is one the largest organs in the abdomen and the most frequent site of metastases for gastrointestinal tumors. Surgery on this complex and highly vascularized organ can be associated with high morbidity even in experienced hands. A thorough understanding of liver anatomy is key to approaching liver surgery with confidence and preventing complications. The aim of this quiz is to provide an active learning tool for a comprehensive understanding of liver anatomy and its integration into clinical practice.

Surgical Anatomy of the Liver-Significance in Ovarian Cancer Surgery.

INTRODUCTION: Ovarian cancer is the leading cause of death among all gynecological malignancies. Most patients present with an advanced stage of the disease. The routes of spread in ovarian cancer include peritoneal dissemination, direct invasion, and lymphatic or hematogenous spread, with peritoneal and lymphatic spread being the most common among them. The flow direction of the peritoneal fluid makes the right subphrenic space a target site for peritoneal metastases, and the most frequently affected anatomical area in advanced cases is the right upper quadrant. Complete cytoreduction with no macroscopically visible disease is the most important prognostic factor. METHODS: We reviewed published clinical anatomy reports associated with surgery of the liver in cases of advanced ovarian cancer. RESULTS: The disease could disseminate anatomical areas, where complex surgery is required-Morrison's pouch, the liver surface, or porta hepatis. The aim of the present article is to emphasize and delineate the gross anatomy of the liver and its surgical application for oncogynecologists. Moreover, the association between the gross and microscopic anatomy of the liver is discussed. Additionally, the vascular supply and variations of the liver are clearly described. CONCLUSIONS: Oncogynecologists performing liver mobilization, diaphragmatic stripping, and porta hepatis dissection must have a thorough knowledge of liver anatomy, including morphology, variations, functional status, potential diagnostic imaging mistakes, and anatomical limits of dissection.

Hyper accuracy three-dimensional (HA3D™) technology for planning complex liver resections: a preliminary single center experience.

Three-dimensional visualization technology (3DVT) has been recently introduced to achieve a precise preoperative planning of liver surgery. The aim of this observational study was to assess the accuracy of 3DVT for complex liver resections. 3DVT with hyper accuracy three-dimensional (HA3D™) technology was introduced at our institution on February 2020. Anatomical characteristics were collected from two-dimensional imaging (2DI) and 3DVT, while intraoperative and postoperative outcomes were recorded prospectively. A total of 62 patients were enrolled into the study. 3DVT was able to study tumor extension and liver anatomy, identifying at least one vascular variation in 37 patients (59.7%). Future remnant liver volume (FRLV) was measured using 2DI and 3DVT. The paired samples t test assessed positive correlation between the two methods (p < 0.001). At least one vessel was suspected to be invaded by the tumor in 8 (15.7%) 2DI cases vs 16 (31.4%) 3DVT cases, respectively. During surgery, vascular invasion was detected in 17 patients (33.3%). A total of 73 surgical procedures were proposed basing on 2DI, including 2 alternatives for 16 patients. After 3DVT, the previously planned procedure was changed in 15 cases (29.4%), due to the clearer information provided. A total of 51 patients (82%) underwent surgery. The most frequent procedure was right hepatectomy (33.3%), followed by left hepatectomy (23.5%) and left trisectionectomy (13.7%). Vascular resection and reconstruction were performed in 10 patients (19.6%) and portal vein was resected in more than half of these cases (66.7%). 3DVT leads to a more detailed and tailored approach to complex liver surgery, improving surgeons' knowledge of liver anatomy and accuracy of liver resection.

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.

All the Routes for Laparoscopic Liver Segment VIII Resection: A Comprehensive Review of Surgical Techniques.

Liver surgery is highly demanding for anatomical, physiological and technical reasons, and minimally invasive approaches have been implemented at a slower rate. Today, laparoscopic liver resection is a standard of care in many occasions, yet specific operations remain particularly challenging and generally performed in open surgery. In particular, SVIII resection may be considered one of the most difficult due to anatomical characteristics including its sub-diaphragmatic position, the deep-lying Glissonean pedicle and the close contact with the inferior vena cava and right and middle hepatic veins. Many techniques have risen to overcome technical difficulties, and today laparoscopic SVIII resection has been demonstrated to be feasible. This review provides a complete picture of current approaches, focusing on all techniques reported so far with critical appraisal of each, discussing and explaining benefits and pitfalls.

Minimally invasive anatomic liver resection: Results of a survey of world experts.

BACKGROUND: Although the number of minimally invasive liver resections (MILRs) has been steadily increasing in many institutions, minimally invasive anatomic liver resection (MIALR) remains a complicated procedure that has not been standardized. We present the results of a survey among expert liver surgeons as a benchmark for standardizing MIALR. METHOD: We administered this survey to 34 expert liver surgeons who routinely perform MIALR. The survey contained questions on personal experience with liver resection, inflow/outflow control methods, and identification techniques of intersegmental/sectional planes (IPs). RESULTS: All 34 participants completed the survey; 24 experts (70%) had more than 11 years of experience with MILR, and over 80% of experts had performed over 100 open resections and MILRs each. Regarding the methods used for laparoscopic or robotic anatomic resection, the Glissonean approach (GA) was a more frequent procedure than the hilar approach (HA). Although hepatic veins were considered essential landmarks, the exposure methods varied. The top three techniques that the experts recommended for identifying IPs were creating a demarcation line, indocyanine green negative staining method, and intraoperative ultrasound. CONCLUSION: Minimally invasive anatomic liver resection remains a challenging procedure; however, a certain degree of consensus exists among expert liver surgeons.

Landmarks to identify segmental borders of the liver: A review prepared for PAM-HBP expert consensus meeting 2021.

BACKGROUND: In preparation for the upcoming consensus meeting in Tokyo in 2021, this systematic review aimed to analyze the current available evidence regarding surgical anatomy of the liver, focusing on useful landmarks, strategies and technical tools to perform precise anatomic liver resection (ALR). METHODS: A systematic review was conducted on MEDLINE/PubMed for English articles and on Ichushi database for Japanese articles until September 2020. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN). RESULTS: A total of 3169 manuscripts were obtained, 1993 in English and 1176 in Japanese literature. Subsequently, 63 English and 20 Japanese articles were selected and reviewed. The quality assessment of comparative series and case series was revealed to be usually low; only six articles were qualified as high quality. Forty-two articles focused on analyzing intersegmental/sectional planes and their relationship with specific hepatic landmark veins. In 12 articles, the authors aimed to investigate liver surface anatomic structures, while 36 articles aimed to study technological tools and contrast agents for surgical segmentation during ALR. Although Couinaud's classification has remained the cornerstone in daily diagnostic/surgical practices, it does not always portray the realistic liver segmentation and there has been no standardization on which a single strategy should be followed to perform precise ALR. CONCLUSIONS: A global consensus should be pursued in order to establish clear guidelines and proper recommendations to perform ALR in the era of minimally invasive surgery.

A snapshot of the 2020 conception of anatomic liver resections and their applicability on minimally invasive liver surgery. A preparatory survey for the Expert Consensus Meeting on Precision Anatomy for Minimally Invasive HBP Surgery.

BACKGROUND: The main aim of this survey was to analyze how liver surgeons perform liver resections and to define their conception of anatomic procedures within the incorporation of minimally invasive liver surgery (MILS). METHODS: The survey was distributed among liver surgeons. It mainly focused on personal experience on open and MILS, methods and landmarks, and experience on anatomic resections and Glissonean approach. RESULTS: A total of 445 valid answers from 54 countries was obtained. Surgeons performing MILS mainly have below 10 years of experience (81.8% of responders) and one third has never done complex MILS. New techniques, including indocyanine green demarcation are marginally used (<25%). More than 60% of surgeons do not make a full exposure of hepatic veins during MILS, mainly due to the risk of injury or not considering it to be of utility. Although 88% of responders agreed with the concept of anatomic resection as the "resection along the border/watersheds of each order division identified by the portal vein flow", only 55% of surgeons have ever performed MILS Glissonean approaches. CONCLUSIONS: Liver anatomy is not a static concept. Anatomic resections need training and precision. Standardization of complex anatomic resections by a minimally invasive approach should be encouraged.

Glissonean approach for hepatic inflow control in minimally invasive anatomic liver resection: A systematic review.

BACKGROUND: The Glissonean approach has been widely validated for both open and minimally invasive anatomic liver resection (MIALR). However, the possible advantages compared to the conventional hilar approach are still under debate. The aim of this systematic review was to evaluate the application of the Glissonean approach in MIALR. METHODS: A systematic review of the literature was conducted on PubMed and Ichushi databases. Articles written in English or Japanese were included. From 2,390 English manuscripts evaluated by title and abstract, 43 were included. Additionally, 23 out of 463 Japanese manuscripts were selected. Duplicates were removed, including the most recent manuscript. RESULTS: The Glissonean approach is reported for both major and minor MIALR. The 1st, 2nd and 3rd order divisions of both right and left portal pedicles can be reached following defined anatomical landmarks. Compared to the conventional hilar approach, the Glissonean approach is associated with shorter operative time, lower blood loss, and better peri-operative outcomes. CONCLUSIONS: Glissonean approach is safe and feasible for MIALR with several reported advantages compared to the conventional hilar approach. Clear knowledge of Laennec's capsule anatomy is necessary and serves as a guide for the dissection. However, the best surgical approach to be performed depends on surgeon experience and patients' characteristics. Standardization of the Glissonean approach for MIALR is important.

Umbilical fissure vein, anatomical variation and potential surgical application.

BACKGROUND: The umbilical fissure vein (UFV) is a hepatic vein that travels within the umbilical fissure (or its proximity), providing venous drainage for hepatic segments 3 and 4. Its preservation carries a potential importance in extended right hemi-hepatectomy, left lateral segmentectomy and extended segment 2 resections. METHODS: Consecutive 1-mm slice thickness portovenous phase intravenous contrast computed tomography (CT) scans of the abdomen performed were retrospectively reviewed during the period of June 2019 to July 2019, with two independent investigators investigating the presence of UFV, its course, insertion and relation to the umbilical fissure. RESULTS: A total of 244 CTs were identified and 186 included. The UFV was identified on 72.8% of participants, 109 (81.4%) drained into the main left hepatic vein, while the remaining ones drained either from the main middle hepatic vein (16.4%) or the bifurcation between main left and middle hepatic vein (2.2%). The veins course lay 2 mm or less along the length of umbilical fissure in 39.5%, while 57.5% ran within 1 cm along the length of the umbilical fissure. CONCLUSION: Pre-operative identification of UFV could assist in operative planning. The vein can be used as a landmark in surgery and should be preserved in left lateral segmentectomy and extended right hepatectomy to avoid parenchymal congestion of remnant segments.

Deceased donor liver transplantation in an adult recipient with situs inversus totalis: A case report of 10-year clinical sequences following primary and repeat transplantation.

The feasibility of liver transplantation (LT) in adult patients with situs inversus (SI) was demonstrated with advances in surgical techniques. However, SI is very rare, and the experience of LT in adult patients with SI is very limited. We present a case of an adult patient with SI who underwent deceased-donor LT and late retransplantation because of chronic rejection. A 42-year-old man with SI totalis who suffered from acute-on-chronic hepatic failure because of hepatitis B virus-associated liver cirrhosis and alcoholic liver disease was referred to our center and underwent successful orthotopic deceased-donor whole-liver transplantation. We used a modified piggy-back technique with cavo-cavostomy and inserted a tissue expander for mechanical support of the unstably located liver graft. The patient recovered uneventfully. At 3 years after the first LT, this patient underwent retransplantation because of chronic rejection. In the second LT, we used similar surgical techniques, but performed splenectomy to make space to accommodate the second liver graft. The patient was discharged after long hospitalization. At 5 years after the second LT, he underwent living-donor kidney transplantation because of chronic renal failure developed after the second LT. Currently, he has done well for 10 years after the first LT. In conclusion, SI is a rare anomalous condition hindering LT. Careful perioperative planning with thorough assessment of the donor and recipient livers and use of patient-tailored surgical techniques can lead to successful LT.

[Research progress in the Hepatobiliary Surgery operation of hepatic hilar plate system].

An estimate of about 50% of new liver cancer cases worldwide occur in China every year.Surgical resection is still the major treatment choice for longer survival of patients with hepatocellular carcinoma. Blocking hepatic blood flow and reducing intraoperative bleeding ensure the success of the operation. Anatomic separation of hepatic hilar region is the precondition of hepatic inflow occlusion. The hepatic hilar plate system involves a thick layer of connective tissue covering the hepatic inflow ducts of hepatic hilar region. The descending part of hilar plate assists in reducing the anatomical difficulty of the hepatic hilar region. The "forth porta hepatis" that is hidden in the hepatic hilar plate system involves the accumulation area of "short hepatic portal veins" .The communicating branch vessels between the hepatic inflow vessels form the anatomical basis in reducing the indocyanine green fluorescence stain effect.The relatively fixed position of the hepatic portal plate is considered as a positioning marker for accurate liver resection. The intrahepatic Glisson sheath is connected with thick connective tissue of the hepatic portal panel system, and is regarded as the physical barrier in limiting the proliferation and hypertrophy of hepatocytes and continuation of hepatic portal panel system in the liver.This paper summarizes the anatomy and application of hepatic hilar plate system during hepatobiliary surgery.