Diffuse Liver Disease

1. Diffuse Liver Disease

2. Diffuse Liver Disease Differentiation of liver disease into diffuse or focal disease is an artificial but convenient way to analyze liver disorders radiographically. Although historical, physical and laboratory testing are the first means for identifying these diseases, imaging may be required as a part of the overall assessmentof the patient. From: Basic Radiology M. Chen et al.

3. Diffuse Liver Disease Except for hemochromatosis, diffuse liver diseases are not an indication for CT scanning. However, CT performed for other indications will commonly show findings that are referable to diffuse hepatic disease. Many of these diseases are associated with an increased incidence of HCC, and multiphasic CT should be performed in patients with elevated alpha-fetoprotein levels or equivocal sonographic findings From:Spiral and Multislice Computed Tomography of the BodyM. Prokop, MGalanski; Thieme, 2003.

4. Cirrhosis

5. Cirrhosis Cirrhosis and chronic liver disease comprise the 10th most common cause of death in the United States since 1994 • In the US and Europe the most common cause of cirrhosis is alcoholism, whereas in Asia, the most common cause of cirrhosis is viral hepatitis

6. Cirrhosis • There are a number of conditions that can lead to cirrhosis: • Primary biliary cirrhosis - an autoimmune liver disease • Primary sclerosing cholangitis - a disease of the bile ducts • Prolonged exposure to environmental toxins • Some forms of heart disease (cardiac cirrhosis) • Schistosomiasis (parasitic infection) • Inherited of congenital disease: • - hemochromatosis - abnormal accumulation of iron in the liver and other organs due to the decreased excretion of iron from the liver • - Wilson’s disease - abnormal accumulation of copper in the liver and other organs due to the decreased excretion of copper from the liver- alpha1-antitrypsin deficiency - inherited absence of a specific enzyme in the liver- glycogen storage diseases - inability to properly utilize sugars- autoimmune hepatitis - progressive inflammation of the liver associated with an abnormality of the body’s immune system Chronic Passive Congestion

7. Cirrhosis • Cirrhosis of the liver is the end stage of a complex process resulting from hepatocyte injury and the response of the liver that leads to partial regeneration and fibrosis. • Nodular regeneration of the liver results in nodular edge of the liver and inhomogeneity of the parenchyma • Most authorities are increasingly convinced that MRI is the most sensitive imaging modality for examination of the liver in cirrhosis and other diffuse diseases of the liver Normal Liver Microcellular cirrhosis Macrocellular cirrhosis

8. Cirrhosis Ultrasound • Real-time US, in combination with color flow Doppler, is currently the most frequently used diagnostic imaging modality worldwide in the screening and evaluation of patients with cirrhosis. • In patients with cirrhosis, the liver parenchyma is coarsened in its echogenic pattern. Surface nodularity is well seen in the presence of ascites. The size of the right lobe of the liver is found to shrink in comparison to the caudate lobe as the cirrhosis progresses.

9. Cirrhosis Ultrasound Surface nodularity is well seen in the presence of ascites. Печень, цирроз печени

10. Cirrhosis Ultrasound Early stages of cirrhosis shows hepatomegaly, ascites and decreased vasulature. From: http://www.gehealthcare.com/

11. Cirrhosis Ultrasound Late stage cirrhosis with ascites and a shrunken liver. From: http://www.gehealthcare.com/

12. Cirrhosis Ultrasound Gallstones are seen in 33-46% of patients with cirrhosis, and their prevalence is known to increase with the duration and severity of liver disease.

13. Cirrhosis CT Findings CT is useful in demonstrating the morphologic evidence of cirrhosis within the liverand in showing mesenteric and GI tract abnormalities and development of collateral vessels in portal hypertension. Early cirrhosis shows a normal liver or enlargement of the hilar periportal space anterior to the right portal vein.

14. Cirrhosis CT Findings Early cirrhosis CT demonstrates irregularity of external contour of left lobe.

15. Cirrhosis CT Findings With progression, morphologic changes are common and include atrophy of the right hepatic lobe and left medial segment and enlargement of the caudate lobe and left lateral segment

16. Cirrhosis MRI Findings • MRI offers an alternative noninvasive method to image the liver based on tissue-specific characteristics. • MRI has not been widely applied in screening except in specialized transplant centers.

17. Cirrhosis Secondary extrahepatic changes of cirrhosis include splenomegaly, portal hypertension, portosystemic collateral vessels, varices, and ascites. Advanced cirrhosis: Portal venous phase CT demonstrating thickened gallbladder wall, splenomegaly, numerous collaterals within omentum (arrow), and marked ascites (A). The liver is atrophic and irregular in external contour.

18. Cirrhosis Portosystemic collateral vessels Portal venous phase CT demonstrating splenomegaly, numerous collaterals within omentum, andsuperficial vessel anastomosing with paraumbilical vessel. Very large varix in the umbilical region (clinically evident as a caput medusa)

19. Cirrhosis Portosystemic collateral vessels Development of extensive collateral vessels at the lower esophagus Ascites and marked splenomegaly Varices are adjacent to and within esophageal wall.

20. Cirrhosis Liver disease is the second most common cause of death in persons with cystic fibrosis. About 5% of individuals with CF have potentially fatal liver disease that requires liver transplantation, Sonogram shows heterogeneous liver architecture. Nodules are visible within the liver and at its edge. The path of the portal veins is deformed by the nodules. A hyperechoic areain the liver probably represents steatosis.

21. Cirrhosis Portosystemic collateral vessels Liver disease is the second most common cause of death in persons with cystic fibrosis. About 5% of individuals with CF have potentially fatal liver disease that requires liver transplantation, Sagittal Doppler sonogram shows the aorta and the nodular contour of the left lobe of the liver. Between these structures, blood flow (blue Doppler signals) within the left gastric vein is hepatofugal and directed toward the esophagus.

22. Cirrhosis More than 500 mL of fluid is usually required for ascites to be diagnosed based on findings from abdominal films. Ascites • Many nonspecific signs indicate ascites: • diffuse abdominal haziness, • bulging of the flanks, • indistinct psoas margins, • poor definition of the intra-abdominal organs, • erect position density increase, • separation of small bowel loops, and centralization of floating gas containing small bowel.

23. Cirrhosis Ascites Real-time sonography is the easiest and most sensitive technique for the detection of ascitic fluid. Volumes as small as 5-10 mL can routinely be visualized. Uncomplicated ascites appears as a homogenous, freely mobile, anechoic collection in the peritoneal cavity that demonstrates deep acoustic enhancement.

24. Cirrhosis Ascites Most patients (95%) with carcinomatous peritonitis have a gallbladder wall that is less than 3 mm thick. Mural thickening of the gallbladder is associated with benign ascites in 82% of cases. The thickening of the gallbladder is primarily a reflection of cirrhosis and portal hypertension. carcinomatous peritonitis ascites associated with cirrhosis

25. Hemochromatosis Hemochromatosis is characterized by a progressive increase in total body iron stores with abnormal iron deposition in multiple organs. Primary hemochromatosis is a genetic disorder (one of the most common genetic diseases in humans), whereas secondary hemochromatosis can be the result of a variety of disorders, most commonly chronic hemolytic anemias. • The organ is shrunken. • The parenchyma shows very coarse nodularity, best seen along the edges of the specimen. • The parenchyma is rusty brown (due to hemosiderin). Cirrhosis and Hemochromatosis

26. Hemochromatosis The use of T2-weighted gradient echo sequence is necessary to detect a slight iron overload. Using this type of sequences, the liver is usually hyperintense to the muscle. A liver hypointense to the muscle indicates a liver iron overload. Normal liver T1 PD T2 In case of slight overload, liver signal intensity decrease can only be seen on T2-weighted gradient echo sequences. The liver is then hypointense to the muscle. T1 PD T2

27. Hemochromatosis MRI is the best imaging examination to evaluate abnormal iron deposition in the liver. Normal liver T1 PD T2 In case of major overload the decrease of the liver signal intensity is depicted on all sequence. T1 PD T2

28. Hemochromatosis CT is less sensitive than MRI but can demonstrate increased iron if it is severe. Patients with increased hepatic iron demonstrate diffuse increased attenuation of the liver, usually greater than 75 Hounsfield units on noncontrast examination. Other abnormalities that can cause increased attenuation of the liver on CT include: amiodarone toxicity, glycogen storage disease, gold therapy, and Wilson disease.

29. Hemochromatosis Ultrasound Iron deposits in the liver usually do not alter liver echogenicity. If sonographic liver abnormalities are present, they are usually secondary to cirrhosis.

30. Fatty liver (Steatosis) • Fatty liver, or steatosis is common disorder. • It is found in up to 50% of patients who are diabetic or alcoholic. • The many causes of fatty liver, besides diabetes or alcoholism, include: • Obesity • Chronic illness • Corticosteroid excess • Parenteral nutrition • Hepatotoxins including chemotherapy Fatty liver may be distributed evenly or focally

31. Fatty liver (Steatosis) When distributed uniformly, fatty liver is recognizable as a pattern of homogeneous increasedechogenicity on US, decreased attenuation on CT, or increased signal intensity on T1-weighted MR images. Ultrasound A sonogram of a fatty liver showing increased echotexture compared with the adjacent kidney

32. Fatty liver (Steatosis) CT Findings Homogenous decreased atenuation

33. Fatty liver (Steatosis) When distributed nonuniformly, it resembles focal disease of the liver in that normal islands of the liver tissue are seen against the background of lower density fatty liver Focal spared fatty liver.

34. Schistosomiasis • Occurs in many tropical and subtropical regions around the world (Africa, South America, the Caribbean, Middle East, southern China, and southeast Asia). Not yet found in the U.S. • Infects as many as 200 million people each year. Of these, 20 million are severely infected. • Second (to malaria) most common disease caused by a parasite. Intestinal schistosomiasis is caused by the species schistosoma mansoni Urinary schistosomiasis is caused by schistosoma haematobium Schistosoma sp. in liver and bladder

35. Schistosomiasis Schistosomiasis is a major source of morbidity and mortality for developing countries in Africa, South America, the Caribbean, the Middle East, and Asia; tourism to, and immigration from, endemic areas can result in schistosomiasis cases presenting anywhere in the developed world. The main forms of human schistosomiasis are caused by five species of flatworms, or blood flukes, known as schistosomes.

36. Schistosomiasis People are infected by contact with infested water during their normal daily activities for personal or domestic purposes, such as hygiene and recreation (swimming), or in professional activities such as fishing, rice cultivation, irrigation, etc. Schistosomiasis Life Cycle

37. Schistosomiasis • Schistosomiasis life cycle leads to a granulomatous inflammation, periportal fibrosis, portal vein occlusion, varices and splenomegaly. • Imaging studies demonstrate periportal fibrosis. Granulomatous reactions to eggs of S. mansoni and S. japonicum in the liver produce a diffuse nodular periportal cirrhosis (pipestem fibrosis).

38. Schistosomiasis • The characteristic periportal fibrosis of hepatic cirrhosis due to S. mansoni infections can be demonstrated by both US and CT scanning. • Both US and CT, may show the dense bands which follow the portal vein branches into the periphery of the liver. • On US the bands are hyperechogenic. Depending on the angle, the foci can be round or linear and the branching pattern allows differentiation from metastases. US scans of the left lobe of the liver showing well-marked periportal fibrosis

39. Schistosomiasis • On CT bands are of low density but enhance strongly with contrast, becoming either homogenous or denser than the surrounding liver. Depending on the angle, the foci can be round or linear and the branching pattern allows differentation from metastases. Nonenhanced CT scans show both round and linear patterns of low density throughout the liver.

40. Schistosomiasis • On CT bands are of low density but enhance strongly with contrast, becoming either homogenous or denser than the surrounding liver. Depending on the angle, the foci can be round or linear and the branching pattern allows differentation from metastases. One minute later there is contrast enhancement of both the linear and circular zones: this pattern persists for several minutes In the early phase of contrast scanning, the inferior vena cava has just filled, and there is compression of the left main portal vein.

41. Schistosomiasis MRI Findings Linear and parenchymal band enhancement is seen. The liver surface can be nodular and fibrosis may show increased periportal fat. MRI images show presence of peripheral hepatic vessels

42. Schistosomiasis With S. haematobium, ulcerations in the bladder wall may cause dysuria and hematuria. Over time, chronic cystitis develops; strictures may lead to hydroureter and hydronephrosis; papillomatous masses in the bladder are common and may become malignant. 1. Calcification of the distal two thirds of both ureters.2. Bladder calcifications.3. Seminal vesicle calcifications superimposed on bladder calcifications.

43. Polycystic Liver Diseases Polycystic liver diseases occurs either in autosomal dominant polycystic kidney disease (ADPKD) or isolated  autosomal dominant polycystic liver disease (ADPLD). Both forms are part of the ductal plate malformation. • Cysts in both syndromes are more prominent in females than in males and they usually grow up to the menopause. • Presentation is usually with: • a feeling of fullness, • pain • symptoms of gastric outlet obstruction.

44. Polycystic Liver Diseases ADPKD on CT scan of the abdomen. There are multiple cysts in both kidneys and in the liver.

45. Polycystic Liver Diseases Ultrasound ADPKD on liver ultrasound scan of the abdomen. There are multiple cysts in both kidneys and in the liver.

46. Polycystic Liver Diseases Multiple cysts have almost completely replaced the liver parechyma. Both kidneys appear normal - ADPLD.