THE LIVER
This presentation is the property of its rightful owner.
Sponsored Links
1 / 49

THE LIVER Methods of examination 1. US 2. CT 3. MRI 4. Nuclear medicine PowerPoint PPT Presentation


  • 51 Views
  • Uploaded on
  • Presentation posted in: General

THE LIVER Methods of examination 1. US 2. CT 3. MRI 4. Nuclear medicine. CIRRHOSIS Pathologically cirrhosis consists of varying amounts of hepatic necrosis, fibrosis, fatty infiltration and nodular regeneration Types :

Download Presentation

THE LIVER Methods of examination 1. US 2. CT 3. MRI 4. Nuclear medicine

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

THE LIVER

Methods of examination

1. US

2. CT

3. MRI

4. Nuclear medicine


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

CIRRHOSIS

Pathologically cirrhosis consists of varying amounts of hepatic necrosis, fibrosis, fatty infiltration and nodular regeneration

Types:

1.Chronic sclerosing cirrhosis – minimal regenerative activity of hepatocytes, little nodule formation, liver is hard and small.

2. Nodular cirrhosis – regenerative activity with presence of many small nodules; initially the liver may be enlarged.

Causes – alcohol, hepatitis B, hemochromatosis


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

Radiographic features

Liver

- Small liver, increased echogenicity, heterogeneous

- Nodular surface

- Regenerating nodules – hypoechoic

- Unequal distribution of cirrhosis in different segments – left lobe appears larger than right lobe; lateral segment of left lobe enlarges, medial segment shrinks; ratio of the width of the caudate lobe to the right hepatic lobe is 0,6

Portal hypertension

- Collaterals – left gastric, paraesophageal, mesenteric, splenorenal

- Splenomegaly

- Ascites

Complications – hepatocellular carcinoma, esophageal varices with bleeding


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

FATTY LIVER

Causes – obesity, alcohol, hyperalimentation, debilitation, chemotherapy, steroids

Radiographic findings

US – fat increases liver echogenicity, renal cortex appears more hypointense relative to liver than normal, intrahepatic vessel borders become indistinct or cannot be visualized, nonvisualization of diaphragm

CT – fatty areas are hypodense, hepatic and portal veins appear dense because of decreased parenchymal density


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

PYOGENIC ABSCESS

Pathogens – Escherichia Coli,aerobic streptococci, anaerobes

Causes – ascending cholangitis, trauma, surgery, portal phlebitis.

Radiographic features

- CT – hypodense with peripheral enhancement, no fill-in.

- Double target sign – wall enhancement with surrounding hypodense zone.

- 30% contain gas.

- any abscess can be drained percutaneously, particularly: deep abscesses, no response to treatment, nonsurgical candidates.


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

HYDATID DISEASE

Humans are intermediate hosts of the dog tapeworm (taenia echinococcus). Two forms:

E.granulosus – more common, few large cysts

E.multilocularis – less common, more invasive

Radiographic features

E.granulosus

- well-delineated cysts

- size of cysts usually very large

- daughter cysts within larger cysts ( multiseptated cysts) are pathognomonic

- rimlike cyst calcification

- double rim sign: pericyst, endocyst

- enhancement of cyst wall


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

  • E.multilocularis

  • - poorly marginated, multiple, hypodense liver lesions.

  • - lesions are infiltrative (chronic granulomatous reaction with necrosis, cavitation).

  • calcifications are punctate and dystrophic, not rimlike.

  • Complications

  • - rupture into peritoneal, pleural, pericardial cavity

  • - obstructive jaundice due to external compression or intrinsic obstruction of biliary tree


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

HEMANGIOMA

- Frequency – 4-7% of population, 80% in females.Hemangiomas may enlarge particularly during pregnancy or estrogen administration.

US

- hyperechoic lesions 80%.

- hypoechoic lesions especially in fatty liver.

- giant hemangiomas are heterogeneous.

- anechoic peripheral vessels may be demonstrated by color Doppler .

CT

- hypodense, well-circumscribed lesion on precontrast scan

globular or nodular intense enhancement.

MRI

- hyperintense on heavily T2W sequences.

- imaging modality of choice.

Nuclear imaging (SPECT)

- decreased activity on early dynamic images.

- increased activity on delayed blood pool images.


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

HEPATOCELLULAR CARCINOMA (HCC)

Risk factors – cirrhosis, chronic hepatitis B, hepatotoxins, metabolic disease in paediatric patients

Radiographic features

General

- three forms – solitary, multiple, diffuse

- portal and hepatic vein invasion is common

- metastases – lung, adrenal, lymph nodes, bone


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

  • CT

  • - hypodense mass lesion

  • - early arterial enhancement

  • Pseudocapsule

  • US

  • - most small HCC are hypoechoic

  • - larger HCC are heterogeneous

  • high-velocity Doppler pattern

  • Angiography

  • - hypervascular

  • - AV shunting is typical

  • - Dilated arterial supply


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

METASTASES

30% of patients who die of malignancy have liver metastases.

Colorectal carcinoma, stomach, pancreas, breast, lung

Sensitivity for lesion detection: CTAP – high-dose delayed CT – CECT,MRI – US

- Echogenic MTS – GI malignancy, HCC, vascular

- Hypoechoic MTS – lymphoma, bull’s eye pattern (hypoechoic halo around lesion)

- Calcified metastases – all mucinous metastases – colon, thyroid, ovary, kidney, stomach

- Cystic metastases – necrotic leyomiosarcoma


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

PORTAL HYPERTENSION

Criteria – hepatic wedge pressure  10 mm Hg. Causes:

Presinusoidal

Extrahepatic (obstruction of portal vein) – thrombosis, compression

Intrahepatic (obstruction of portal venules) – hepatic fibrosis, infection

Sinusoidal

Cirrhosis ,sclerosing cholangitis

Postsinusoidal

Budd-Chiari syndrome, congestive heart failure

Radiographic features

- Portal vein diameter  13 mm

- Collateral vessels – gastroesophageal varices via coronary vein, azygos; SMV collateral – mesenteric varices; splenorenal varices; IMV collateral – hemorrhoids

- Splenomegaly

- Ascites


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

  • THE BILIARY SYSTEM

  • Methods of examination

  • Abdominal plain film – gas or calcium in the biliary tract

  • US

  • CT

  • MRI + MRCP

  • ERCP

  • PTC

  • Scintigraphy


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

ACUTE CHOLECYSTITIS

Causes - gallstone 95%

US

- Luminal distension  4cm

- Wall thickening  5 mm (edema, congestion)

- Gallstones

- Pericholecystic fluid

Complications

- Gangrenous cholecystitis: rupture of GB

- Emphysematous cholecystitis

- Empyema


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

CHRONIC CHOLECYSTITIS

- GB wall thickening (fibrosis, chronic inflammation)

- Gallstones

- Failure of GB to contract


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

CHOLELITIASIS

Types:

Cholesterol stones are caused by precipitation of supersaturated bile

- Pigment stones – precipitate of calcium bilirubinate

- Mixed stones

Predisposing factors:

- Obesity

- Hemolytic anemia

- Abnormal enterohepatic circulation of bile salts

- Diabetes

- Cirrhosis

- Hyperparathyroidism

US – method of choice – hyperreflective image with prominent posterior shadow; mobility of stones (exception – stones impacted in neck or stones adherent to wall)


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

CHOLANGIOCARCINOMA

Adenocarcinoma of the biliary tree.

Clinical – jaundice, pruritus, weight loss.

Treatment – pancreaticoduodenectomy or palliative procedures ( stent placement, biliary bypass)

Location – hilar (originates from epithelium of main hepatic ducts or junction –Klatskin tumor) + peripheral – originates from epithelium of intralobular ducts

Radiographic features

- Dilated intrahepatic ducts

- Hilar lesions – central obstruction + lesions are usually infiltrative so that a mass is not usually apparent + encasement of portal veins causes irregular enhancement by CT

- Peripheral lesions – may present as a focal mass or be diffusely infiltrative + retain contrast materials on delayed scans + occasionally invade veins

- ERCP very useful


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

  • THE PANCREAS

  • Methods of examination

    • CT

    • US

    • MRI + MRCP

    • Arteriography


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

PANCREATITIS

Classification

- Mild acute pancreatitis (interstitial edema)

- Severe acute pancreatitis (necrosis, fluid collections)

- Chronic pancreatitis

Causes

- Alcohol

- Cholelitiasis

- Abdominal trauma

- Hyperlipidemia, hypercalcemia

- Drugs – azathioprine, sulfonamides

- Peptic ulcer

- Pregnancy


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

Imaging – CT staging

Grade A – normal pancreatic appearance

Grade B – focal or diffuse enlargement of pancreas

Grade C – pancreatic abnormalities and peripancreatic inflammation

Grade D – 1 peripancreatic fluid collection

Grade E – 2 peripancreatic fluid collections and/or gas

Complications

- Necrosis

- Acute fluid collections – enzyme-rich pancreatic fluid, no fibrous capsule

- Pseudocyst – encapsulated collection of pancreatic fluid

- Abscess

- Hemorrhage


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

CHRONIC PANCREATITIS

Progressive, irreversible destruction of pancreatic parenchyma by repeated episodes of mild or subclinical pancreatitis.

Radiographic features

Commonly small, atrophic pancreas

Fatty replacement, fibrosis, calcifications

Irregular dilatation of pancreatic duct

Complications

Pseudocysts

Obstructed CBD

Venous thrombosis – splenic, portal, mesenteric

Carcinoma

Malabsorbtion


The liver methods of examination 1 us 2 ct 3 mri 4 nuclear medicine

NEOPLASM

Types

Exocrine pancreatic tumor – adenocarcinoma, cystic neoplasm

Endocrine pancreatic tumor – insulinoma, gastrinoma

Other tumors – lymphoma, metastases

ADENOCARCINOMA

Clinical – jaundice, weight loss, Courvoisier sign (enlarged, nontender gallblader)

Radiographic features

Mass effect

Alterations of density

Extrapancreatic extension

Vascular involvement

Metastases


  • Login