Surgical anatomy of Liver, Concept of liver.pptx

concept of surgical anatomy of liver

1. Surgical anatomy of Liver, Concept of liver resection Pushpa Lal Bhadel FCPS Resident Department of Surgery Kathmandu Model Hospital Moderator Dr. Bijendra Dhoj Joshi

2. Introduction Greek word for liver, hêpar derives from hepaomai : mend/repair Importance dates back to Babylonians (c. 2000 B.C.): seat of the soul 1654, Francis Glisson described essential anatomy of blood vessels of liver 1716, Berta amputated portion of liver in patient with self inflicted stab wound First recorded elective hepatic resection: 1888, by Langenbuch , Germany

3. Introduction Liver resection in US (Tiffany, 1890) and Europe ( Lucke , 1891) 1897, Elliot “ friable, so full of gaping vessels and so evidently incapable of being sutured that it had always seemed impossible to successfully manage large wounds of its substance” 1908, Pringle: “arrest of hepatic hemorrhage due to trauma” 1950s works by Couinaud , Hjortsjo , Healey, Lortat -Jacob and Starzl : modern era of hepatic resection surgery Blumgart , Bismuth, Longmire, Fortner, Schwartz, Starzl , and Ton deserve mention

4. Anatomy Solid GI organ (1.2 to 1.6 kg) Located in right upper quadrant Hematopoietic function in fetal life Glisson’s capsule: fibrous layer Two accessory lobes: Caudate lobe Quadrate lobe Separated by deep transverse fissure (porta hepatis)

5. Anatomy Caudate lobe: Upper aspect of visceral surface Between IVC and fossa due to ligamentum venosum Quadrate lobe: Lower aspect of visceral surface Between GB and fossa due to ligamentum teres

6. Anatomy Supports of Liver Primary: IVC Hepatic veins Coronary and triangular ligaments Secondary supports: Right kidney Right colonic angle Duodenopancreatic complex Tertiary supports: Liver attachment to anterior abdominal wall and diaphragm by falciform ligament

7. Liver surfaces Diaphragmatic surface : Anterosuperior surface Smooth and convex Bare area of liver: posterior aspect not covered by visceral peritoneum IVC embedded in deep sulcus in left side of bare area Peritoneal ligaments: coronary, left and right triangular and falciform ligaments

8. Liver surfaces Visceral surface : Posteroinferior surface Covered with peritoneum except: Fossa of gall bladder Porta hepatis Irregular and flat In contact with abdominal organs Umbilical fissure

9. Ligaments of liver Falciform ligament Coronary ligament (anterior and posterior fold) Triangular ligament (left and right) Ligamentum venosum

10. Hepatic recesses Subphrenic spaces   –  Between the diaphragm and the anterior and superior aspects of the liver Divided into a right and left by the falciform ligament. Subhepatic space  – Subdivision of the supracolic compartment (above the transverse mesocolon) Between the inferior surface of the liver and the transverse colon.

11. Hepatic recesses Morison’s pouch   – Between the visceral surface of the liver and the right kidney. Deepest part of the peritoneal cavity when supine (lying flat) Pathological abdominal fluid such as blood or ascites collect in a bedridden patient.

12. Embryology Liver primordium as an outgrowth of endodermal epithelium Begins to form in 3 rd week of development Hepatic diverticulum/liver bud Connection between hepatic diverticulum and future duodenum narrows to form bile duct, gall bladder and cystic duct Intermingle with vitelline and umbilical veins to form hepatic sinusoids Develop hematopoietic cells and Kupffer cells and connective tissue

13. Development of liver and biliary passages The hepatic diverticulum enlarges rapidly and divides into two parts ie pars hepatica(cranial bud) and pars cystica(caudal bud) as it grows between the layers of the ventral mesentery . Superior Caudal bud Inferior Gall bladder, cystic duct Ventral pancreas Ref: Sleisenger and Fordtran's Gastrointestinal and Liver Disease

14. Pars hepatica It is the larger cranial part of the hepatic diverticulum . Gives rise to: Hepatocytes Hepatic sinusoids Kupffer cells and hematopoietic tissue Intrahepatic bile ducts The liver grows rapidly : fill a large part of the abdominal cavity. At first, the 2 lobes are of the same size but soon the right become larger.

15. Pars cystica Becomes the gall bladder and the stem of the diverticulum forms the cystic duct . The stalk connecting the hepatic and the cystic ducts to the duodenum becomes the common bile duct The right and the left branches of the pars hepatica canalized to form the right and the left hepatic ducts. Bile begins to flow at about the 12th w eek

16. Development of Liver Pars cystica Endoderm Pars hepatica Hepatocytes Hepatic sinusoids Kupffer cells and hematopoietic tissue Intrahepatic biliary tree Gall bladder Extrahepatic bile ducts (cystic duct ,CBD) Ventral mesentery Mesoderm Visceral peritoneum of liver Falciform ligament Septum Transversum Cardiogenic mesoderm Hepatoblast Hepatic diverticulum Kupffer cells derive from circulating monocytes and possibly yolk sac macrophages. Reference: Sherlock's Diseases of the Liver and Biliary System, 12th Ed

17. Vascular Development related to Liver Extraembryonic Major Venous system Intraembryonic Vitelline veins Cardinal Veins Umbilical Veins Sinus venosus

18. Embryology Fig. A . Umbilical and vitelline vein development of a 5-week-old embryo. The hepatic sinusoids have developed, and although there are channels that bypass these sinusoids, the vitelline and umbilical veins are beginning to drain into them.

19. Embryology Fig. B. S econd month, the vitelline veins drain directly into the hepatic sinusoids Fig. C. T hird month, the vitelline veins have formed into the portal system (splenic, superior mesenteric, and portal veins)

20. Congenital anomalies of liver Riedel lobe : T ongue-like, inferior projection of the right lobe of the liver beyond the level of the most inferior costal cartilage Anatomical variant of the right lobe of the liver Congenital solitary nonparasitic cysts of the liver Congenital Hepatic Fibrosis Congenital vascular malformation of the liver Intrahepatic Biliary Atresia Mesenchymal Hamartoma Accessory and Ectopic Lobes of the Liver

21. Congenital anomalies of liver Anomalous supradiaphragmatic lobe

22. Microscopic Anatomy Functional unit: acinus or lobule Originally described by Rappaport Modified by Matsumoto and Kawakami Lobule : Polygonal unit Made up of central terminal hepatic venule Surrounded by 4-6 terminal portal triads Blood flows from terminal portal triad through sinusoids into terminal hepatic venules

23. Hepatocytes Complex multifunctional cells 60% of cell mass 80% of cytoplasmic mass of liver Polyhedral cell with central spherical nucleus 3 surface types Facing space of Disse Bile canaliculi Adjacent hepatocytes

24. Hepatocytes Organelle Function Rough endoplasmic reticulum Protein synthesis Smooth endoplasmic reticulum Drug biotransformation Peroxisomes B-oxidation of fatty acids Mitochondria ATP synthesis, Steroid and Nucleic acid metabolism, Deamination of Catecholamines Golgi apparatus Albumin, Lipoprotein storage Lysozyme Autolysis, Pigment deposition Microtubules Bile secretion

25. Other cell types Kupffer cells Hepatic stellate cells/ Ito cells Endothelial cells T & B lymphocytes Dendritic cells Cholangiocytes

26. Portal Vein Provides approx. 75% of hepatic blood inflow 50-70% of liver oxygen requirement Forms behind neck of pancreas at the confluence of superior mesenteric vein and splenic vein Length: 5.5 to 8 cm Diameter: 1 cm

27. Portal Vein

28. Portal Vein Fig. Anatomy of the Portal Vein. The superior mesenteric vein (SMV) joins the splenic vein (SV) posterior to the neck of the pancreas (shaded area) to form the portal vein.

29. Portosystemic shunt

30. Hepatic artery Provides approx. 25% of hepatic blood flow Provides 30-50% of its oxygenation Common anatomy present in 60% Fig. Most Common Anatomy of the Celiac Axis and Hepatic Arterial System

31. Hepatic artery variations

32. Hepatic artery variations

33. Hepatic artery buffer response Maintains constant hepatic inflow by modifying hepatic artery blood flow Inverse relationship between portal vein and hepatic artery Hepatic artery flow changes according to portal vein but reverse is not true Mechanism: Adenosine washout hypothesis: secreted by smooth muscle Increased oxygen extraction (Post-prandial)

34. Hepatic artery buffer response

35. Hepatic veins Three main hepatic veins drains from superior-posterior surface of liver into IVC Right hepatic vein: most of right liver Middle and left hepatic vein joins intrahepatically and enters left side of IVC Umbilical vein empties into left hepatic vein Small posterior venous branches from right posterior sector and caudate lobe drain directly into IVC

36. Nerve supply Sympathetic supply: T7-T10 Parasympathetic from Vagal nerve Hepatic arteries via sympathetic fibers Gallbladder and extrahepatic bile ducts via sympathetic and parasympathetic fibers

37. Lymphatics Drain to lymph nodes at hepatoduodenal ligament Continues along hepatic artery to Celiac LN Finally to Cisterna chyli

38. Functional Anatomy Historically divided into left and right lobe : falciform ligament Cantlie’s line : Vertical plane extending from IVC posteriorly to GB fossa anteriorly Divides liver into left and right lobes Fig. Cantlie’s line

39. Functional anatomy Described in 1957 by Goldsmith and Woodburne and by Couinaud Composed of eight segments Each supplied by single portal triad/ pedicle Portal triad: portal vein, hepatic artery and bile duct Further organized into 4 sectors separated by scissurae containing 3 main hepatic veins 4 sectors are even further organized into right and left liver

40. Fig. Schematic Depiction of the Segmental Anatomy of the Liver

41. Fig. Segmental Anatomy of the Liver

42. Systematic approach to segmentation Term Definition Lobes: The right and left lobes are separated by the umbilical scissura Livers: The right and left livers are separated by the plane of the middle hepatic vein or the plane of the gallbladder Sectors: Parts of a hemi-liver vertically separated by the plane of the right, middle and left hepatic veins Segments: Independent functional units receiving an artery, a portal vein, and drained by a hepatic vein, horizontally separated by the plane passing by the portal vein bifurcation

43. Systematic approach to segmentation

44. Systematic approach to segmentation

45. Systematic approach to segmentation

46. Systematic approach to segmentation

47. Systematic approach to segmentation

48. Systematic approach to segmentation

49. Functions of liver Energy Functional heterogeneity Blood flow Bile formation Enterohepatic circulation Bilirubin metabolism Carbohydrate metabolism Lipid metabolism Protein metabolism Vitamin metabolism Coagulation Metabolism of drugs and toxins (Xenobiotics) Regeneration

50. Liver resection

51. History of modern liver surgery 1888 : Carl Johann August Lagenbuch (German) – first successful hepatic resection 1 1890 : McLane-Tiffany – resected liver tumor at Johns Hopkins 1891 : Lucke – reported first successful removal of malignant tunor 1899 : Keen – performed first anatomical left lateral segmentectomy (sectionectomy) Modern liver surgery began in 1950s 1 Langenbuch C. Ein Fall von Resecktion eines linksseitigen Schnurlappens der Leber. Berl Klin Wochenschr. 1888;25:37.

52. History of modern liver surgery 1952 : Lorat Jacob (France) – published manuscript on his experiences performing anatomic liver resections 1 1956 : Claude Couinaud : segmental division of liver 2 1958 : Lin – introduced the finger fracture technique 3 Clamp crushing/’ Kellyclasia 1984 : introduction of intraoperative ultrasound: ‘ Hepatectomie à la carte’ 3 Lin TY, Tsu K, Mien C, Chen C. Study on lobectomy of the liver. J Formosa Med Assoc. 1958;57:742–9 2 Couinaud C. Lobes et segments hépatiques. Presse Med. 1954;62:709 1 Lortat -Jacob JL, Robert HG. Well defined technic for right hepatectomy. Presse Med. 1952;60:549–51

53. History of modern liver surgery Pringle maneuver: to reduce blood loss during liver resection 1950s works by Couinaud , Hjortsjo , Healey, Lortat -Jacob and Starzl : modern era of hepatic resection surgery Blumgart , Bismuth, Longmire, Fortner, Schwartz, Starzl , and Ton deserve mention Development of new devices: harmonic scalpel, LigaSure , tissue link, radiofrequency, Habib sealer, CUSA

54. Indications Benign liver tumors Hemangioma Adenoma Cystadenoma Malignant liver tumors HCC Cholangiocarcinoma Metastasis Carcinoma GB Benign conditions Intrahepatic stones Recurrent Pyogenic Cholangitis Caroli’s disease Hydatid cyst Liver cysts Liver trauma LDLT (Living donor liver transplantation)

55. IHPBA Brisbane 2000

56. Liver resection steps Pre-op planning Intra-op assessment Inflow control Outflow control Maintenance of low central venous pressure Parenchymal transection

57. Functional Liver volume

58. Methods of liver volume augmentation Portal Vein Embolization (PVE) PVE + TACE (Trans Arterial Chemo Embolization) Staged Hepatic Resection

59. Portal Vein Embolization Indications Normal liver (ICG retention rate at 15 minutes [ICG R15] <10%) if FLRV/TLV is less than 40% Injured liver (10% < ICG R15 < 20%), if FLRV/TLV is less than 50% If ICG R15 exceeds 20%, major hepatectomy is Contraindicated even after PVE

60. Results of PVE PVE leads to an increment of segmental volume in non embolized hemi liver and a decrement of segmental volume in embolized hemi liver maintaining a constant TLV In case of right hemi liver PVE, regeneration rate of the Non cirrhotic liver – 12 cm 2 /day at 2 weeks 11 cm 2 /day at 4 weeks 6 cm 2 /day at 32 days In cirrhotic patients regeneration is slower

61. Complications of PVE

62. TACE Embolization  Ischemia  Necrosis Ischemia  blocks transmembrane pumps  limits chemotherapy from washing out of tumor cells (Ramsey D et al, 2002) Concentration of chemotherapy drug in tumor is 10-100 times greater than given systemically (Konno T et al,1990) Chemotherapy + lipiodol traps chemotherapy & concentrates in HCC (Ramsey D) Because most of the drugs is retained in the liver, systemic toxicity is reduced (Daniels JR, 1988)

63. TACE Exclusion criteria Hepatic encephalopathy PV thrombosis Serum bilirubin >5mg/dl; serum creatinine >2mg/dl

64. TACE Procedure 7-10ml of chemotherapy solution infused (100mg cisplatin, 50mg doxorubicin & 10mg mitomycin C in a 1:1 or 2:1 volume ratio with ethiodol / lipiodol) Followed by infusion of 1-2ml of gelfoam / PVA particles (300-500 micron) to slow down arterial inflow & prevent washout of chemotherapeutic agents End point - entire amount is delivered & slowed arterial flow as compared to initial flow Forward flow in the HA is to be maintained to preserve patency for re-treatment and minimize theoretical risk of ischemia or infarction

65. TACE Complications: Post-embolization syndrome (fever, pain, vomiting, ALT) – 32-80% Ascites, GI bleed, leucopenia, worsening hepatic function -- <10% Rare – cholecystitis, ischemic hepatitis, abscess, bacteremia, hepatic, renal failure, death

66. Vascular control Inflow Vascular Occlusion Total Vascular Exclusion

67. INFLOW VASCULAR OCCLUSION Pringle Maneuver Oldest and simplest way Hepatoduodenal ligament encircled with tape Until pulse in hepatic artery disappears Pringle JH et al, ann surg 1909

68. INFLOW VASCULAR OCCLUSION Pringle Maneuver Advantages Little general hemodynamic effect No specific anesthetic management Disadvantages Backflow from hepatic veins Ischaemic-reperfusion injury to the liver parenchyma Splanchnic congestion Kim YI et al, J hepatobiliary pancreat surg 2003

69. I nflow V ascular O cclusion Continuous Pringle Maneuver Up to 60 minutes in normal liver (normothermic conditions) Up to 30 minutes in pathological (fatty or cirrhotic) livers

70. I nflow V ascular O cclusion Intermittent Pringle Maneuver 15-20 minutes clamping, 5 minutes unclamping 5 minutes clamping, 1 minute unclamping Advantages Doubling of ischaemia time Better tolerated by pathological liver Disadvantages Bleeding during unclamping period Increased overall transection time Torzilli G et al, arch surg 1999 Belghiti J et al, ann surg 1999

71. I nflow V ascular O cclusion Ischaemic Preconditioning Endogenous self-protective mechanism Hypothesis: 10 minutes of ischaemia followed by 10 minutes of reperfusion  protection against subsequent transection with complete inflow occlusion Advantage: Lower serum transaminase levels after surgery Longer inflow occlusion in steatotic livers Clavien et al, ann surg 2000

72. Hemi-hepatic clamping (Half-Pringle maneuver) Interrupts arterial and portal inflow selectively one lobe Advantage Avoids ischaemia in the remnant liver Avoids splanchnic congestion Clear demarcation of the resection margin Disadvantage Bleeding from the parenchymal cut surface Horgan PG et al, am J surg 2001

73. Total vascular exclusion Complete mobilization of the liver Encircling of suprahepatic and infrahepatic IVC Pringle maneuver Clamping the infrahepatic IVC & suprahepatic IVC

74. Total vascular exclusion Hemodynamic changes Marked reduction of venous return and cardiac output Trial clamping of two to five minutes Ischemia time 60 minutes in normal liver 30 minutes in diseased liver Extended with hypothermic perfusion of the liver Azoulay D et al, ann surg 2005

75. Total vascular exclusion Disadvantages Hemodynamic intolerance Post-operative abdominal collections/ abscesses and pulmonary complications Venovenous bypass if hemodynamic intolerance Infrahepatic IVC clamp alone with inflow occlusion Reduce back bleeding Abdalla et al, surg clin north am 2004

76. Selective Vascular control Inflow occlusion with extraparenchymal control of hepatic veins Trunks of major hepatic veins can be safely looped in 90% of patients Loops tightened or vessels clamped after inflow occlusion Continuous or intermittent Advantages Liver lobe isolated from systemic circulation Caval flow un-interrupted Elias D wt al, hepatogastroenterology 1998 Smyrniotis VE et al, world J surg 2003

77. Metastasectomy American Hepato-Pancreato-Biliary Association, the Society for Surgery of the Alimentary Tract, and the Society of Surgical Oncology in 2006 Positive surgical margin is associated with a higher local recurrence and worse OS and should be avoided whenever possible. While a wide (>1 cm) resection margin should remain the goal when performing a liver resection, an anticipated margin of <1 cm should not be used as an exclusion criterion for resection Assessment of resectability of hepatic colorectal metastases should focus on the ability to obtain a complete resection (negative margins). The presence of extrahepatic disease should no longer be considered an absolute contraindication

78. Metastasectomy The feasibility of hepatic resection should also be based on three criteria related to the remaining liver following resection: T he ability to preserve two contiguous hepatic segments, Preservation of adequate vascular inflow and outflow as well as biliary drainage, and The ability to preserve adequate future liver remnant (>20 percent in a healthy liver; >30 percent after chemotherapy).

79. Conventional indications Modern aggressive approach <4 metastases, unilobar disease No limits. Multiple/bilobar metastases acceptable, using neoadjuvant chemotherapy, staged resection, and resection/local ablative therapy. Size <5 cm No limits No extrahepatic disease Pulmonary metastases can be resected Resection margin >1 cm Resection margin <1 cm managed with ablative treatment of narrow margin (cryosurgery or radiofrequency ablation) Adequate remnant liver parenchyma Preoperative portal vein embolization to increase liver remnant volume Resection of all macroscopic disease NED can be achieved with combination of resection and local ablative therapy No metachronous liver metastases Synchronous and metachronous metastases acceptable Absence of vena cava and hepatic vein confluence invasion No limits. Caval/hepatic vein resection with reconstruction can be performed Absence of hepatic pedicle lymph node metastases In absence of celiac axis metastases, hepatic pedicle lymph node metastases may be resected for improved 3-year survival

80. Surveillance after Metastasectomy Guidelines from the National Comprehensive Cancer Network (NCCN) CEA testing every 3-6 mths for two years, then every 6 mths for three years. CT of the chest/abdomen and pelvis every 3-6 mths for two years, then every 6 to 12 mths up to a total of five years. Colonoscopy in one year; if no advanced adenoma, repeat in three years, then every five years; if advanced adenoma is found, repeat in one year.

81. Metastasectomy Simultaneous resection  — When simultaneous resection is performed, the liver resection is performed first Staged resection  — Traditionally, patients were treated with initial resection of the colorectal primary followed by administration of systemic chemotherapy and CRLM resection two to three months later as long as there was no disease progression Classic (colorectal-first) approach Reverse (liver-first) approach

82. P arenchymal T ransection

83. I nstruments CUSA W ater-Jet HABIB P robe H armonic F ocus L igasure V ascular S taplers

84. Laparoscopy First anatomical laparoscopic liver resection 1996 by Azagra Left lateral sectionectomy for hepatic adenoma Small and localized tumors on anterolateral segments Oncological principal has to be followed Need of intra-operative ultrasound

85. Laparoscopic assisted hepatectomy (LAH) Total laparoscopic liver resection (TLLR) Laparoscopy

86. Liver resection: Complications Blood loss Bile leakage Post-operative liver failure : 6.3% (Vyas et al., 2014)

87. Associating Liver Partition & Portal Vein Ligation For Staged Hepatectomy (ALPPS) Indications Marginally resectable or primarily non-resectable locally advanced liver tumors of any origin with an insufficient FLR either in volume or quality Need to perform major liver resections combined with synchronous resection of other organs (i.e. Colorectal cancer and liver metastases, neuroendocrine pancreatic, or intestinal tumors with massive liver metastases)

88. References Sabiston Textbook pf Surgery, 20 th edition Schwartz’s Principles of Surgery. 10 th edition Bailey & Love’s short practice of Surgery, 27 th edition Blumgart’s Surgery of Liver, Biliary tract and Pancreas, 6 th edition