General HPB 
PG02 General HPB: Imaging (ePoster) 
Selection of ePoster Presentations from Abstract Submissions
PG02-01 Surgical Simulation and Navigation for HPB Surgery
Yukio Oshiro, Japan

Y. Oshiro, R. Udo, R. Imazato, K. Nishida, J. Shimazaki, M. Shimoda, S. Suzuki
Department of Gastroenterological Surgery, Tokyo Medical University, Ibaraki Medical Center, Japan

Introduction: In Japan, preoperative 3D simulation and navigation are becoming popular in hepato-biliary-pancreatic (HPB) surgery. Herein, we report various surgical simulations and navigations in HPB surgery in our department.
i) We have developed a novel liver surgical navigation system that measures the shape of liver, its position, the cut surface/cut line in real time and gives feedback to the simulation software, using 3D camera.
ii) ICG fluorescence navigation has been performed in seven cases of laparoscopic cholecystectomy. ICG fluorescence was observed with VISERA ELITE II (Olympus Co., Ltd., Tokyo).
iii) We perform simulation and navigation using 3DCT image when performing pancreatectomy.
i) A total of six cases have been performed: lateral, posterior segmentectomy and left, right lobectomy. The surgical field of a hepatectomy that progresses during the real operation was measured with two 3D cameras. The group of measurement points was converted to polygon, and the cut line was extracted. The position of the cut surface/cut line was projected on the 3DCG model.
ii) Although the ICG fluorescence intensity in the bile duct was slightly weak and difficult to confirm in 3 cases with high inflammation, ICG fluorescence navigation was effective in 4 cases in which bile duct was confirmed.
iii) In pancreatectomy, important blood vessels such as hepatic artery, GDA, SMA, SMV, and pancreatic arcade can be routinely confirmed by 3DCT before and during surgery, so that we were able to perform the operation safely.
Conclusions: Surgical simulation and navigation for HPB surgery have become indispensable.
PG02-02 Clinical Value of Fluorescent Cholangiography for the Patients with Infrapotal Type of the Right Posterior Bile Duct during Single-Incision Laparoscopic Cholecystectomy
Tsuyoshi Igami, Japan

T. Igami, T. Ebata, Y. Yokoyama, T. Mizuno, J. Yamaguchi, S. Onoe, N. Watanabe, M. Nagino
Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, Japan

Introduction: Reports about clinical value of fluorescent cholangiography using indocyanine green (ICG) during single-incision laparoscopic cholecystectomy (SILC) were increasing. We report clinical value and pitfalls of fluorescent cholangiography during SILC for the patients with the infraportal type of the right posterior bile duct.
Methods: Our SILC procedure utilized the SILS-Port with an additional 5-mm forceps through the umbilical incision. Before SILC, 1 mL of ICG (2.5 mg) was administrated by intravenous injection. For fluorescent cholangiography, ICG fluorescent laparoscope system was used.
Results: We performed fluorescent cholangiography during SILC in 13 patients with the infraportal type of the right posterior bile duct. All procedures were completed successfully. The interval from the injection of ICG to the first obtained fluorescent cholangiography before the dissection of Calot's triangle ranged from 40 to 60 minutes. Detectability of infraportal type of the right posterior bile duct before dissection in Claot's triangle was 23.1% (n = 3) and that during dissection in Calot's triangle was 53.8% (n = 7). The infraportal type of the right posterior bile duct could be identified under fluorescent cholangiography only when it joined into the common hepatic duct.
Conclusions: Utilization of fluorescent cholangiography can lead SILC to safe even for the patients with the infraportal type of the right posterior bile duct. Its benefit is emphasized when the infraportal type of the right posterior bile duct joins into the common hepatic duct.
PG02-03 Spleen Metastases: Criteria of Diagnostics
Yulia Stepanova, Russian Federation

Y. Stepanova, M. Alimurzaeva, D. Ionkin, A. Glotov
Oncology, A.V. Vishnevsky National Medical Research Center of Surgery, Russian Federation

Spleen metastases occupy a special place both from the point of view of the rarity of the lesion, and from the position of the mechanisms of their occurrence that haven't been fully studied.
Objective: to define the spleen metastases criteria's of diagnosis on the basis of own experience.
Materials and methods: Оver 450 patients with spleen's lesions were treated at A.V. Vishnevsky NMRC of Surgery (1985-2019), there were 13 spleen metastases (ovaries cancer - 4, colorectal cancer - 2, in one case of pancreas, duodenum, thyroid cancer, hepatocellular carcinoma, stomach carcinoid and lymphomas, retroperitoneal polymorphcellular sarcoma). All tumors were morphologically/histologically verified.
Results: Spleen metastasis parameters':
• clinical manifestations are only at considerable sizes of lesion(s);
• multiple nature of lesion (quite often);
• probability of defeat of several bodies (liver/lungs/bone);
• mainly subcapsular localization;
• low-resistant arterial blood-groove in metastasis at duplex scanning;
• low MSCT-/MR-density, uniformity of structure of lesions;
• at MSCT: lesions are hypodenses zones without accurate contours (native); insignificant accumulation of contrast agent, thus lesion remains hypodense in relation to a parenchyma in all contrast phases; clearness of contours due to emergence of hypercontrast rim;
• lymphadenopathy of an abdominal cavity is possible;
• the increase in a spleen's sizes can't serve as diagnostic criterion;
• ascites (quite often).
Conclusion: In case of any spleen lesion detection it's necessary to carry out differential diagnostics with malignant tumoral process, despite a relative rarity of similar lesions. Oncological vigilance is necessary in case of cystic lesions detection too.
PG02-07 Whipple's Pancreaticoduodenectomy Requiring Total Gastrectomy
Prekshit Chhaparwal, India

P. Chhaparwal, P. Varshney, A. Nagar, A. Sharma
Surgical Gastroenterology, Mahatma Gandhi Medical College and Hospital, India

Multiple neoplastic lesions at separate gastrointestinal sites is rare with incidence of 0.7-11%. Majority of Multiple primary neoplasms (MPN's) are double primary lesions while triple/quadruple malignancies is extremely rare with a ratio of 2.7:1. Patients with periampullary lesions having lesion in stomach or gastroesophageal junction are rare. These patients requiring Whipple's pancreaticoduodenectomy (PD) with resection of the adjoining stomach for R0 Resection is rarely reported.
Material and methods: We report three cases of periampullary carcinoma with associated lesions in stomach in two patients and lesion at GE junction and pylorus in one. These patients have undergone Whipple's PD with subtotal or total gastrectomy and reconstruction. Usually Whipple's PD shall require resection of antrum and gastrojejunostomy. If pylorus preserving Whipple's is done then duodenojejunostomy is required for reconstruction. In the cases presented here, we did a proximal gastrojejunostomy in two and esophagojejunostomy in one patient. In all these surgeries feeding jejunostomy was done. All patients had a smooth postoperative course. Two patients had GIST in stomach on biopsy. One patient had no evidence of malignancy in spite of a PET positive lesion at gastroesophageal junction and pylorus.
Conclusion: Whipple's PD with subtotal or total gastrectomy for en mass resection of lesions is a feasible option for a patient having periampullary carcinoma with multiple lesions (duodenum, stomach and oesophagus).
Keywords: Malignancy, Multiple primary neoplasms, PET-CT
PG02-10 Variations in the Anatomical Liver Volume and the Function Based on 99m Technitium-Mebrofinate SPECT-CT Scan and Its Relation to the Primary Indication for Resection
Bobby VM Dasari, United Kingdom

B.V. Dasari, M. Wilson, K.J. Roberts, R.P. Sutcliffe, N. Chatzizacharias, R. Marudanayagam, D.F. Mirza, P. Muiesan, J. Isaac
HPB and Liver Transplantation Unit, Queen Elizabeth Hospital, United Kingdom

[Figure 1]

Introduction: 99m Technetium -Mebrofinate SPECT-CT scan is a pre-operative investigation useful in assessing the global, lobar and the dynamic liver function. The study is aimed at assessing the discordance in the function (scintigraphy) within the given volume of the liver remnant and to assess if the variation is related to the primary indication for resection.
Methods: All patients who underwent 99m Tc-Mebrofenin SPECT-CT scan in the unit since 2018 were included. Data were processed on a workstation (MultiModality; Hermes Medical Solutions) to assess the anatomical volumes, global and lobar liver function assessed as scintigraphy as well as the dynamic uptake. Data was collated from a prospectively maintained database.
Results: Seventy seven 99m Tc-Mebrofenin SPECT-CT scans were included. Three patients had the scan prior to the second stage liver resection. Median remnant anatomical volume was 685ml (range: 135-1906ml). Median global dynamic uptake was 13.19/min (range: 4.66-27.4). Percentages of the anatomical volume vs. functional distribution in the remnant liver were shown in Figure 1. There was no variation in 17/77 scans (22%), up to 4.9% variation in 31/77 scans (40%), 5-9.9% variation in 12/77 scans (15.5%), and more than 10% variation in 17/77 scans (22%). More than 5% discordence was noted in 50% with primary liver cancers in comparison to 22% with colorectal liver metastases (p=0.025).
Conclusion: Distribution of liver function is non-homogeneous and is more significant in patients with primary liver cancers. 99m Tc-Mebrofenin SPECT-CT or equivalent should be considered in the pre-operative assessment of patients undergoing major liver resections.
PG02-11 Relevance of Adipose Tissue Accumulation and Muscularity in Patients Undergoing Liver Resection
Karolina Grąt, Poland

K. Grąt1, M. Grąt2, M. Morawski2, J. Borkowski2, M. Skalski2, P. Kalinowski2, A. Zhylko2, O. Rowiński1, K. Zieniewicz2
1Second Department of Clinical Radiology, Medical University of Warsaw, Poland, 2Department of General, Transplant and Liver Surgery, Medical University of Warsaw, Poland

Introduction: Nutritional status is known to affect the quality of liver parenchyma. This study aimed to evaluate the relevance of the amount of adipose and muscular tissue assessed on computed tomography (CT) in patients undergoing liver resection.
Methods: In this prospective observational study, 64 patients undergoing liver resection underwent preoperative CT assessment of height-normalized amount of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and total adipose tissue (TAT), smooth muscle (SM) and psoas muscle (PM). The primary outcome measure was early injury and function of remnant liver, as reflected by immediate (within 24 hours) and peak serum transaminases activity, international normalized ratio (INR), and bilirubin concentration.
Results: Median SAT, VAT, TAT, SM, and PM were 65.4, 41.0, 115.1, 47.8, and 5.9 cm2/m2, respectively. TAT was significantly correlated with macro- (R=0.43; p=0.001) and microvesicular (R=0.36; p=0.007) liver steatosis, with stronger impact of subcutaneous than visceral fat. In patients undergoing minor resections (n=29), SM was positively correlated with early (R=0.53; p=0.004) and peak (R=0.43; p=0.020) bilirubin and SAT (R=0.43; p=0.031), VAT (R=0.51; p=0.007), and TAT (R=0.50; p=0.010) were positively correlated with early INR. Interestingly, in patients without relevant liver steatosis (< 30%), SAT (R=0.48; p=0.034) was additionally positively correlated with early aspartate transaminase activity and VAT (R=0.48; p=0.029) and TAT (R=0.55; p=0.010) with peak aspartate transaminase activity.
Conclusion: Excessive amount of adipose tissue exacerbates injury and negatively influences early liver remnant function after minor liver resections. Increased muscularity may lead to increased bilirubin concentrations of undetermined clinical significance.
PG02-12 Intraoperative ICG Fluorescence Allows for Improved Accuracy in Lymph Node Harvest in Robotic Gastric Cancer Surgery
Imran Siddiqui, United States

I. Siddiqui
Surgical Oncology and HPB Surgery, Hartford Healthcare St. Vincent Medical Center, Bridgeport, United States

Introduction: Gastric cancer surgery requires adequate margin negative resection along with loco regional D1 and D2 lymphadenectomy. Traditionally, associated morbidity limited performance of D2 lymphadenectomy. Current technology utilizing robotic assisted techniques has allowed for safe performance of D2 lymphadenectomy. We describe using IndocyanineGreen (ICG) fluorescence technique to improve lymph node harvest and increase accuracy.
Methods: We inject indocyanine green dye into the sub mucosa around the tumor in four quadrants (5mm away from the tumor site) using intraoperative endoscopy in the operating room prior to proceeding with the gastrectomy. Robotic gastrectomy and lymphadenectomy is performed using standard JGCA guidelines. Lymphadenectomy is performed using robotic camera in the visual spectrum and near infrared fluorescence. All lymph nodes with fluorescence are removed. Pathologic evaluation of the lymph nodes is performed.
Results: 10 consecutive patients underwent robotic gastrectomy with lymphadenectomy from September 2017 to December 2019. Conversion rate was 0. Most common preop stage was uT3N1 Patients underwent preoperative chemo in 77% of patients and chemo radiation in 12%. Margin negative rate was 100%. Median lymph node harvest was 30 and median positive/total nodes percentage was 3/30 nodes. Median follow up is 18 months.
Conclusion: Utilizing ICG fluorescence in the OR to enable D2 lymphadenectomy improves lymph node harvest and serves as a sentinel mapping tool to allow for inclusive lymphadenectomy. Further evaluation using markers to study if the lymph nodes with fluorescence indeed presented with a higher positive rate of lymph node metastases needs to be done.
PG02-14 Laparoscopic Ultrasonography in Hepato-pancreato-Biliary Surgery
Il-Young Park, Korea, Republic of

I.-Y. Park
Surgery, Bucheon St. Mary Hospital, Catholic University of Korea, Bucheon City, Korea, Republic of

Laparoscopic surgery is now popular in the field of hepato-pancreato- biliary (HPB) surgery. Laparoscopic Ultrasonography (LUS) is more familiar to surgeons than other doctors because abdominal anatomy is well understood by them. Furthermore, combination of laparoscopy and ultrasonography in the operating theater can be a distinguishable tool for surgeons.
Between July 2009 and December 2018, we performed 521 Intra-operative ultrasonography at Bucheon St. Mary Hospital, Catholic University of Korea. LUS underwent 195 in HPB patients. The patients were liver malignancies (18), liver benign lesions(26), Gallstones and suspicious common bile duct stones (62), Gallbladder cancer (5), gallbladder benign disease(63), malignancy staging and biopsy (11) and pancreatic lesions(10).
LUS is usable for detection of tumor, discern relation of tumor with its surrounding tissue, determine resectability and to perform surgical procedures. LUS gives more information to the performing surgeon that generally leads to a better outcome. With LUS, surgeons can detect more additional nodules than conventional radiologic techniques. LUS makes surgeons available to detect unknown lesions, find out its characteristics and gather more information on surrounding vascular structures. LUS is also used in guided procedures.
After learning the LUS technique, HPB surgeon are able to provide optimal care for their patients by using the LUS. We conclude that the use of LUS is a minimal, less time consuming and highly accurate method during HPB surgery. HBP surgeons are not only capable of utilizing LUS skillfully, but also of developing numerous applications.
PG02-15 Cholesterol Hepatolithiasis Detection with Dual Spectral CT
Izhar-Ul Haque, Australia

I.-U. Haque1, S. Atlas2, C. Apostolou1
1Hepato Pancreatico Biliary Surgery, Bankstown Hospital, Australia, 2Radiology, Bankstown Hospital, Australia

Introduction: Hepatolithiaisis with cholesterol stones can sometimes be difficult to diagnose in a dilated biliary system with standard CT abdomen. Dual Spectral CT reconstruction can allow better visualisation of stones including cholesterol stones.
Methods: This is a retrospective view of a Hepatolithiasis patient whose disease was diagnosed using Dual Spectral CT.
Results: A 53 yo male presented to our Emergency Department with recent RUQ pain. He had a previous open cholecystectomy overseas 15 years ago. CT showed a dilated Cystic duct with Extrahepatic Bile Duct stones and there was extra and intrahepatic duct dilatation but intrahepatic stones were not clear on standard CT abdomen. Reconstruction of the CT images using dual spectral techniques (45keV) allowed us to visualize the intrahepatic cholesterol stones better and plan our surgery. He underwent Open Bile Duct Exploration with Clearance of intra (Right lobe sided) and extahepatic ducts and Roux-en-Y HepaticoJejunostomy reconstruction.
Dual-Energy Spectral CT provides better visualisation of iso-dense stones (Cholesterol stones). Given the lower dose, it has less overall radiation exposure and can be used without using higher dose in arterial view. Iso-dense Gallstones have a similar density to surrounding bile and can be difficult to diagnose on CT.
Conclusions: Small Cholesterol stones in the liver can be better displayed on dual Spectral CT and can aid in diagnosis and management.
PG02-16 Intraoperative Use of Indocyanine Green Fluorescence in Hepatobiliary and Pancreatic Cancer Resections: Current State and Considerations
Christina Delimpalta, United Kingdom

C. Delimpalta
General Surgery, James Paget University Hospital NHS Trust, Great Yarmouth, United Kingdom

Introduction: Surgery for hepatobiliary and pancreatic malignancies often has unfavourable outcomes due to incomplete resection, with positive histopathological margins and locoregional metastases. Intraoperative use of indocyanine green fluorescence (ICG) with near-red infrared light can improve tumor detectability and achieve R0 status.
Methods: Review of current literature.
Results: ICG fluorescence and bile excretion allows for real-time visualisation of malignant tissues and assessment of resection margins. In liver surgery it can identify subcapsular lesions, a property especially useful in minimally invasive surgery where there is loss of tactile feedback and direct visual inspection. It can also delineate hepatic segmental anatomy for anatomical resections. Hepatocellular carcinomas tend to uniformly uptake ICG, whereas primary or metastatic adenocarcinomas like cholangiocarcinomas and colorectal liver metastases as well as poorly differentiated hepatocellular carcinomas show rim enhancement.
In pancreatic cancer, fluorescence of the resection margin has been shown to correspond to presence of malignancy on histopathological assessement. ICG can also help to detect micrometastases and extrahepatic spread and distinguish between scar tissue and disease following neoadjuvant chemoradiotherapy.
However the technique has limitations: wide variability of method and dose of administration, no visualisation of deep seated lesions, high background fluorescence, false positives up to 40% requiring additional verification by other modalities like intraoperative ultrasound or frozen section for newly detected lesions.
Conclusion: ICG fluorescence can offer increased detectability of malignancy and improve post-operative outcomes in hepatobiliary and pancreatic resections. However there are limitations such as superficial depth of detection and low specificity which need improvement to achieve maximum benefit.
PG02-17 Is There a Role for Sentinel Lymph Node Biopsy in HPB Malignancies? A Summary of Current Practice
Christina Delimpalta, United Kingdom

C. Delimpalta
General Surgery, James Paget University Hospital NHS Trust, Great Yarmouth, United Kingdom

Introduction: In HPB surgery radical lymph node dissection is often necessary to achieve true R0 resections, but carries significant risks. Sentinel lymph node (SNL) biopsy has been rarely used so far but could help identify those patients who would most benefit. Herein we look into current state of practice.
Methods: Review of current literature.
Results: In hepatobiliary malignancies tumors commonly requiring radical lymphadenectomy are intrahepatic cholangiocarcinoma and gallbladder cancer. However hepatic lymphatic drainage is unpredictable and SNL mapping has been used to highlight first line nodes and thus avoid unnecessary dissection and increased morbidity from extensive hilar nodal clearance. Both methylene blue dye and ICG fluorescence have been used as tracer materials.
In colorectal liver metastases almost 15% of patients have nodal microinfiltration, but radical lymphadenectomy has been proven unnecessary for up to 80%. It is thought that site of involvement is the most crucial prognostic factor for recurrence, and again here SNL mapping can identify the subset of patients to benefit from nodal clearance.
In pancreatic cancer local recurrence reaches 30%. Lymphoscintigraphy with Tc99m and use of gamma probe intraoperatively has yielded good results but does not allow for visual identification. ICG is also promising but methylene blue has shown poor penetration.
Conclusion: SNL biopsy can play a role in identifying patients with HPB malignancies who require radical lymphadenectomy. However data is still limited, the injected tracers used suboptimal and there is no consensus on technique or result interpretation. Hence more research is required before it becomes usual practice.
PG02-20 Augmented Holographic HPB Surgical Navigation Using Extended Reality: XR (VR/AR/MR)
Maki Sugimoto, Japan

M. Sugimoto
Innovation Lab, Teikyo University Okinaga Research Institute, Tokyo, Japan

Surgical navigation have become essential for surgeons to accurately and safely perform HPB operations. HPB surgery requires a high degree of spatial awareness and orientation because of complex anatomies and procedures. The traditional navigation for HPB surgery was displayed only for 2D observation on a flat screen by surgeons, the image-based navigation interface is separated from the operating area, and the surgeon needs to switch the field of vision between the screen and the patient's lesion area. We developed extended reality (XR) navigation that combines virtual reality (VR), augmented reality (AR), and mixed reality (MR), and holographic technology for HPB surgery to provide more spatial and intuitive information to surgeons.
From patient's individual CT data, organs and abnormal lesions were extracted into individually colored 3D polygons, and represented into real space with a transparent holographic wearable glasses built-in position sensors (HoloLens and MagicLeap) using our original XR application.
In results, each organ was floated in the actual surgical space These holographic organ models were able to share and move freely in all directions by gesture interface, and complex procedures could be confirmed with pointing by all surgeons. The ability to spatial awareness for understanding the extent of resection, blood vessel processing, and lymph node dissection were improved during surgery. Our XR navigation system has high accuracy and stability for registration.
Our patient-specific XR surgical navigation is highly effective and reduce surgical time, blood loss, and adverse event. This system must have value for future HPB surgeons
PG02-21 CBD Evaluation with MRCP in Acute Mild Billiary Pancreatitis
Srinivasulu Uppalapati, India

S. Uppalapati, M. Ibrarullah, M.S. Modi, S.K. Parida, H. Wani
Surgical Gastroenterology, Apollo Hospital, India

Introduction: Gall stones as an aetiology represent 40-60% cases of acute pancreatitis with variations due to diagnostic efforts and availability of imaging tools. Accurate diagnosis of acute biliary pancreatitis(ABP) is of utmost importance because clearance of lithiasis (gallbladder and common bile duct, CBD) rules out recurrences, very frequent otherwise, with 30% to 50% of the patients developing recurrent acute pancreatitis relatively soon after discharge (average time 108 d), some of them maybe more severe than the previous episode. Therefore, All patients should undergo specific imaging, preferably MRCP, to exclude choledocholithiasis as LFTs and ultrasonography are inaccurate in predicting common bile duct stones.
Methods: An analytical observational study was carried out at an eastern indian Tertiary care centre from January 2012 to October 2019. All patients with mild acute gall stone pancreatitis were included in the study. MRCP was done at the time of index admission. All patients underwent laproscopic cholecystectomy. Additional ERCP was done for those with CBD stones on MRCP
Results: 70% (56 out of 80) patients came to the hospital within 1 week of onset of symptoms. The cumulative rate of choledocholithiasis (on MRCP) was 12.5% that is 10 out of 80 patients at index admission, of which 60% were within the 1st week of onset of symptoms.
Conclusion: Early performance of MRCP can help in selecting patients for ERCP before cholecystectomy. Therefore routine CBD evaluation should be encouraged in cases of mild biliary pancreatitis.