1. HEPATOBILIARY SURGERY- LIVER
K.Winczakiewicz

2. Anatomy of the liver
Liver is one of the heaviest organs in the body, weighing kg. It has been traditionally divided into the left and right lobes, by the falciform ligament, fissure of the ligamentum teres and fissure of the ligamentum venosum.
Advances in hepatic surgery, however, have indicated a more useful division into right and left hemilivers based on the hepatic blood supply. The right and left hemilivers are further divided into a total of eight segments in accordance with subdivisions of the hepatic and portal veins. The segments each have their own hepatic artery branch and biliary tree. Each segment is made up of multiple smaller units knows as lobules, comprised of a central vein, radiating sinusoids separated from each other by single liver cell (hepatocyte) plates and peripheral portal tracts.
Hepatic lobule has no functional significance.
The functional unit of the liver is the hepatic acinus (anatomically is almost the reverse of the hepatic lobule).

3. Anatomy of the liver
Blood flows into the hepatic acinus via the single terminal branches of the portal vein and hepatic artery located in the portal tracts, and along the hepatic sinusoids; It then drains into several hepatic venous tributaries at the periphery of the acinus.
The hepatocytes in each acinus can be divided functionally into the 3 zones, in accordance with their position relative to the terminal portal tract.

4. Hepatic acinus

5. Physiology of the liver
The various functions of the liver are carried out by the liver cells or hepatocytes. The liver is thought to be responsible for up to 500 separate functions, usually in combination with other systems and organs. Currently, there is no artificial organ or device capable of emulating all the functions of the liver. Some functions can be emulated by liver dialysis, an experimental treatment for liver failure.
The liver plays a major role in carbohydrate, protein, amino acid, and lipid metabolism.
The liver is responsible for the breakdown of insulin and other hormones. The liver breaks down bilirubin via glucuronidation, facilitating its excretion into bile. The liver is responsible for the breakdown and excretion of many waste products.
The liver stores a multitude of substances, including glucose (in the form of glycogen), vitamin A (1–2 years' supply), vitamin D (1–4 months' supply)[citation needed], vitamin B12 (1–3 years' supply), vitamin K, iron, and copper.

6. Physiology of the liver
The liver is responsible for immunological effects—the reticuloendothelial system of the liver contains many immunologically active cells, acting as a 'sieve' for antigens carried to it via the portal system.
The liver plays a key role in digestion, as it produces and excretes bile (a yellowish liquid) required for emulsifying fats and help the absorption of vitamin K from the diet. Some of the bile drains directly into the duodenum, and some is stored in the gallbladder.
The liver also produces insulin-like growth factor 1 (IGF-1), a polypeptide protein hormone that plays an important role in childhood growth and continues to have anabolic effects in adults.
The liver produces albumin, the most abundant protein in blood serum. It is essential in the maintenance of oncotic pressure, and acts as a transport for fatty acids and steroid hormones.
The liver synthesizes angiotensinogen, a hormone that is responsible for raising the blood pressure when activated by renin, an enzyme that is released when the kidney senses low blood pressure.

8. Investigation of hepatobiliary disease
Detection of hepatic abnormality: measurement of the liver function tests or “LFTs” (bilirubin, aminotransferases, alkaline phosphatase, gamma glutamyl transferase, albumin). They provide little prognostic information and don’t indicate a specific diagnosis, although may point to and underlying pathological process.
Biochemical tests
Coagulation tests (ex. Prothrombin time)
Radiological imaging in liver disease: USG (especially gallstones and biliary obstruction), CT (same as USG, but smaller focal lesions), MRI (aetiology of focal liver lesions), MRCP, ERCP or PTC
Liver biopsy

9. Benign lesions HEMANGIOMA
Hemangioma is the most common benign hepatic tumor and liver is the most common location (except for the skin and mucous membranes)
Women are affected more often than men in ratio 6:1
Histologically, hepatic hemangiomas are of the cavernous type.
Those greater than 4cm may cause abdominal pain or a palpable mass. Rare patients have presented with the hemorrhagic shock resulting from the spontaneous rupture
Occasionally, hemangioma may behave as an arteriovenous fistula and produce cardiac hypertrophy and CHF.
Large needle biopsy id hazardous, but aspiration biopsy with a fine needle is safe (nevertheless, biopsy is rarely indicated, since diagnosis can be made by CT or MRI or angiography)
Symptomatic hemangiomas should be excised by lobectomy or enucleation.
Exogenous estrogens may contribute to the recurrence of giant hemangiomas, so in this group of patients they should be proscribed.

10. Hemangioma

11. Benign lesions
CYSTS
Hepatic cysts are usually solitary lesions that produce no symptoms. The occasional large cyst may present as an upper abdominal mass or discomfort
Most solitary cysts have a serous lining. Solitary cysts lined by cuboidal epithelium are classified as cystadenomas and should be resected, since they are premalignant.
Multiocular cysts are usually neoplastic (and those must be excised)
Simplest method of treatment consist of laparoscopic excision of the superficial portion of the cyst wall.
The possibility of echinococcosis should always be considered in patients with just one or two cysts (parasitic cysts might be ruptured and the parasite thus allowed to spread, that’s why should be excised as well).

12. Liver cyst USG

13. Benign lesions HEPATIC ADENOMA
Hepatic adenomas occur almost exclusively in women and appear to be related to the widespread of oral contraception
The tumors are soft, yellow tan and those that cause symptoms are in the 8- to 15-cm range.
Transition from benign hepatic adenoma to hepatocellular carcinoma may occur, with liver cell dysplasia as an intermediate step. Hemorrhage may be present
About 50% of patients are asymptomatic. Most of those with symptoms present with right upper quadrant pain or acute intra-abdominal hemorrhage and shock
Liver function tests and AFP levels are usually normal; Hepatic CT and USG scans show a focal defect.
Symptomatic adenomas should be resected , in acutely bleeding patients, this may be lifesaving. Some may be removed by wedge resection, but deep-seated or large lesions usually require partial hepatectomy.
Hepatic adenomas may regress when OC are discontinued, and those should be proscribed permanently in all such cases.

14. Hepatic adenoma

15. Benign lesions
FOCAL NODULAR HYPERPLASIA -FNH is a benign lesion with no malignant potential; Its found in women twice as often as in men (average around 40) -The use of OC may stimulate the development or growth of this tumor -The tumor is a well-circumscribed, firm, tan mass measuring usually 2-3cm. -There are nodular aggregations of normal-appearing hepatocytes without central veins or portal triad. Bile duct proliferation is present in the nodules. -Most patients are asymptomatic. The few with symptoms present with upper quadrant mass, discomfort, or both. Unlike hepatic adenomas, these lesions rarely grow or bleed. -Hepatic function tests and AFP levels are usually normal -CT scans demonstrate the tumor and usually the central stellate scar -Patients taking OC should have these drugs withdrawn -Symptomatic lesions should be removed (but asymptomatic ones left undisturbed).

16. FNH

17. Primary liver cancer
-There are 3 main cellular types of primary liver cancer : hepatocellular carcinoma (hepatoma), cholangiocellular carcinoma (cholangiocarcinoma), and a mixed form (hepatocholangioma). -Hepatomas consitute about 80% of primary hepatic cancers. Their gross morphology allows separation into 3 classes: a massive form (single, predominant mass, clearly demarcated from the surrounding liver), a nodular form, composed of multiple nodules, and a diffuse type, characterized by infiltration of the tumor throughout the remaining parenchyma. There is also uncommon variety of the massive type, fibrolamellar hepatoma, containing numerous fibrous septa and may resemble focal nodular hyperplasia. Fibrolamellar hepatoma occurs in a younger group of patients (25y.o) and is not associated with cirrhosis and hepatitis B infection. -In 70% of patients. The tumor has spread outside the liver, when hepatoma is first diagnosed. Metastases are almost invariably present with the nodular and diffuse forms, but 40% of the massive type are confined to the liver. The hilar and celiac lymph nodes are most commonly involved. Also frequently metastases are to the lung and peritoneal surface. -Chronic hepatitis B and C virus infection is the principal etiologic factor. Cirrhosis from almost any cause is associated with an increased risk of hepatocellular carcinoma. -Cholangiocarcinomas make up about 15% of primary liver cancer -Angiosarcoma of the liver, a rare fatal tumor, has been seen in workers exposed to vinyl chloride for prolonged time.

18. Primary liver cancer
-Early cases are present with right upper quadrant pain. Weight loss is usually present, and jaundice is sometimes also evident. -Hepatomegaly or a mass is palpable in many patients. Intermittent fever may be a presenting feature. -The pattern of presentations are : pain with or without hepatomegaly, suddent deterioration of the condition of a cirrhotic patient, or sudden, massive intraperitoneal hemorrhage, or acute illness with fever and abdominal pain. -Serum bilirubin is elevated in 30%, in another 25% ALP is increased, but serum bilirubin normal; About 75% Of patients are positive for HBsAg or hepatitis C. -CT scans, USG, MRI, angiography usually indicate tumor -AFP is present in high concentrations in the serum of many patients with primary hepatomas (values above 200 ng/mL are suggestive of hepatoma); The prognosis is worse when AFP levels are high -Complications: intra-abdominal hemorrhage or obstruction of the portal vein (portal hypertension), or Budd-Chiari syndrome may occur.

19. Primary liver cancer
TREATMENT: -partial hepatectomy -liver transplant -ethanol injection -radiofrequency ablation -arterial chemoembolization MOST PATIENTS WITH UNRESECTBLE LESIONS DIE WITHIN A YEAR AFTER DIAGNOSIS!

20. Primary liver cancer

21. Metastatic cancer
-Metastatic cancer is 20 times more common than primary tumors in the liver. Cancers of the breast, lung, pancreas, stomach, large intestine, kidney, ovary, and uterus account for about 75% of cases. Spread to the liver may be through systemic circulation, portal vein, or, the lymphatics. -Lung is most commonly involved and contains tumor in 30% of cases -Weight loss, fatigue, anorexia are the presenting general complaints. Right upper abdominal pain, ascites, and jaundice are the usual symptoms. In 60% of cases, physical examination reveals hepatomegaly or a palpable metastatic tumor in the upper abdomen. Portal hypertension may be present. -Serum bilirubin is increased in almost half of the patients. ALP is also usually increased. -Detection of liver metastases usually relies on CT or USG, or MRI. Treatment: -Little treatment is available -Hepatic resection -Radiofrequency ablation -Chemotherapy

22. Metastatic cancer

23. Liver abscesses
-Liver abscesses can be classified as pyogenic, hydatid or amoebic PYOGENIC LIVER ABSCESSES -Uncommon, but important, and potentially curable, inevitably fatal if untreated, and readily overlooked -Causes: biliary obstruction, direct extension, trauma, infection, hematogeneous (portal vein, hepatic vein) -Most common in older patients and usually results from ascending infection due to biliary obstruction or contiguous spread from an empyema of the gallbladder. -Immunocompromised patients are likely to develop the abscesses. -Patients generally ill with fever, rigors and weigh loss. Abdominal pain is the most common symptom. Pain may be pleuritic in nature. Hepatomegaly is found in more than half of patients and tenderness is present. Mild jaundice may be present -Treatment include antibiotic therapy and drainage of the abscess. -Mortality of the liver abscesses is 20-40%; failure to make the diagnosis is the most common cause of death.

24. Liver abscesses

25. Liver abscesses
HYDATID CYSTS: -Caused by Echinococcus granulosus infection. -They have outer layer derived from the host, an intermediate laminated layer and an inner germinant layer -Chronic cysts become calcified. Cysts may be asymptomatic, but may present with abdominal pain or mass. -There may be an eosinophilia -X-RAY may show calcifications -All patients are treated with albendazole or mebendazole prior to definitive therapy

26. Liver abscesses
AMOEBIC LIVER ABSCESSES: -Caused by Entamoeba histolytica -Up to 50% of cases don’t have a previous history of intestinal disease. Patients can present with no history of travel to endemic places. -Abscesses are usually large, single and located in the right lobe. Multiple abscesses may occur in advanced disease. -Fever and abdominal pain or swelling are the most common symptoms.

27. Liver cysts
SOLIATRY HEPATIC CYSTS: -Isolated hepatic cysts may be discovered by chance. Rarely they give rise to complications, including pain and jaundice from cyst enlargement, hemorrhage, infection. Portal hypertension and bleeding from varices are exceptional. -Diagnosis: USG -Resection: if symptoms are troublesome.

28. Liver cysts
CHOLEDOCHAL CYSTS: -Cysts anywhere in the biliary tree -Great majority cause diffuse dilatation of the common bile duct (type 1), but others take the form of biliary diverticula (type 2), dilatation of the intraduodenal bile duct (type 3) and multiple biliary cysts (type 4). -May be recurrent jaundice, abdominal pain, cholangitis. Liver abscess and biliary cirrhosis may develop and there is increased risk of cholangiocarcinoma. -Excision of the cyst can be made by hepaticojejunostomy.

29. Liver cysts

30. Liver transplantation
-Liver transplantation or hepatic transplantation is the replacement of a diseased liver with some or all of a healthy liver from another person (allograft). The most commonly used technique is orthotopic transplantation, in which the native liver is removed and replaced by the donor organ in the same anatomic location as the original liver. -Liver transplantation is aviable treatment option for end-stage liver disease and acute liver failure. Typically three surgeons and two anesthesiologists are involved, with up to four supporting nurses. -The surgical procedure is very demanding and ranges from 4 to 18 hours depending on outcome. Numerous anastomoses and sutures, and many disconnections and reconnections of abdominal and hepatic tissue, must be made for the transplant to succeed, requiring an eligible recipient and a well-calibrated live or cadaveric donor match.

31. Liver transplantation
-Liver transplantation is potentially applicable to any acute or chronic condition resulting in irreversible liver dysfunction, provided that the recipient does not have other conditions that will preclude a successful transplant. Uncontrolled metastatic cancer outside liver, active drug or alcohol abuse and active septic infections are absolute contraindications. -While infection with HIV was once considered an absolute contraindication, this has been changing recently. Advanced age and serious heart, pulmonary or other disease may also prevent transplantation (relative contraindications). -Most liver transplants are performed for chronic liver diseases that lead to irreversible scarring of the liver, or cirrhosis of the liver. Some centers use the Milan criteria to select patients with liver cancers for liver transplantation

32. Liver transplantation
-Living donor surgery is done at a major center. Very few individuals require any blood transfusions during or after surgery. All potential donors should know there is a 0.5 to 1.0 percent chance of death. Other risks of donating a liver include bleeding, infection, painful incision, possibility of blood clots and a prolonged recovery.[10] The vast majority of donors enjoy complete and full recovery within 2–3 months.