Week 11: Gastrointestinal Pathologies Part 3

Question 1

Cholelithiasis

Answer 1

• gallstones
• most made out of cholesterol (radiolucent)
• pigment stones contain calcium (radiopaque)
• gallstones can leave gallbladder though bile duct and enter GI tracts (some get stuck on the way)

Question 2

Cholelithiasis Radiographic Appearance

Answer 2

• if contain calcium, may show up on plain radiographs
• us is modality of choice for confirmation and diagnosis
• CT with contrast can be used for confirmation/diagnosis
• ERCP: treatment/removal

Question 3

Cholecystitis

Answer 3

• acute inflammation of the gallbladder
• usually occurs after impacted gallstone obstructs the cystic duct
• may require surgery
• gallstones may injure the mucosal wall, allowing bacteria to enter
• can become emphysematous cholecystitis: acute infection of gallbladder wall by gas forming organs = surgical emergency)

Question 3

Cholecystitis Radiographic Appearance

Answer 3

• us used for diagnosis
• may see air around gallbladder and/or stones on ct/xray

Question 4

Choledocholithiasis

Answer 4

• the presence of at least one gallstone within the common bile duct
• may block duct
• radiographic appearance: may see stones themselves or filling defect for blocked duct

Question 4

Cholangitis

Answer 4

inflammation of the entire bile duct system

Question 5

Hepatitis

Answer 5

• inflammation of the liver, usually from a viral infection
• hepatitis A/E, B or C

Question 6

Hepatitis A and E

Answer 6

transmitted from fecal oral route: consumption of food or water contaminated with fecal particles, often from poor hand hygiene

Question 6

Hepatitis B

Answer 6

contracted by exposure to contaminated blood or blood products, or through sexual contact

Question 7

Hepatitis C

Answer 7

common cause of chronic hepatitis , cirrhosis and hepatocellular carcinoma; contracted by blood transfusion or sexual contact

Question 8

Hepatitis Radiographic Appearance

Answer 8

• early hepatitis not seen on imaging
• enlarged liver may be seen on plain radiography as a lifting of the right hemidiaphragm as the enlarged liver pushes on it
• complications (cirrhosis and hepatocellular carcinoma/liver cancer) show up on us, ct and mri

Question 9

Liver Cirrhosis

Answer 9

• end stage liver disease, chronic destruction of liver cells and structures
• major cause is alcoholism (10-20 yrs), viral hepatitis, or drugs/chemicals
• fibrous connective tissue (scar tissue), which has no liver cell function, replaces the destroyed liver cells
• liver initially enlarged due to regeneration but then shrivels as scarring contracts and become bumpy and nodular
• decreed albumin production causes fluid to leak out of circulation (edema of lower limbs)
• decreased albumin and increased venous pressure produces ascites
• portal vein obstruction creates collateral circulation
• jaundice occurs from destruction or blockage of bile ducts

Question 10

Liver Cirrhosis Radiographic Appearance

Answer 10

• fat may accumulate in the liver (liver darker than spleen)
• portal veins may stand out more
• spleen enlarges due to portal vein pressure form the liver

Question 11

Ascites

Answer 11

• accumulation of fluid in the peritoneal cavity, usually due to liver damage (hepatitis, cirrhosis, fatty liver)
• causes abdominal distention
• tight, hard abdomen
• increase technical factors

Question 12

Ascites Radiographic Appearance

Answer 12

• plain radiographs show general haziness (ground glass appearance)
• supine: fluid gravitates to lower portions of pelvis (posterior) and collects on both sides of the bladder (dog ear sign)
• CT: extra visceral Lowe density fluid collection

Question 13

Hepatocellular Carcinoma

Answer 13

• liver cancer
• most commonly occurs with underlying liver disease (alcoholic or post necrotic cirrhosis, HBV, HCV

Question 14

Hepatocellular Radiographic Appearance

Answer 14

• CT: tumour appears as a large solitary mass or multi nodular (small number of lesions)
• with contrast: dense, diffuse, non-uniform enhancement, may see tumours within hepatic portal venous systems
• 3 phase liver study recommended
• haptic mets show as well marginated lesions less dense than normal liver parenchyma

Question 15

Liver Hemangiomas - Benign Vascular Tumours

Answer 15

• hepatic or cavernous hemangiomas, usually asymptomatic
• if over 10cm = giant hemangioma
• can cause edema and jaundice

Question 16

Liver Hemangiomas - Benign Vascular Tumours Radiographic Appearance

Answer 16

• ct, mri or us used for diagnosis
• hypotenuse lesions on unenhanced images
• enhancement on contrats images
• persistent enhancement during delayed phase

Question 17

Acute Pancreatitis

Answer 17

• enzymes activates that cause pancreas to digest itself
• common cause excessive alcohol consumption, less often from gallstones blocking ampulla or water causing inflammatory response as bile refluxes into pancreas
• jaundice may occur if swollen pancreas blocks bile duct

Question 18

Chronic Pancreatitis

Answer 18

• repeated injury causes formation of scar tissue
• usually alcohol related
• pancreas cannot produce digestive enzymes (insulin and glucagon)

Question 19

Acute Pancreatitis Radiographic Appearance

Answer 19

• the most obvious thing on a plain radiograph might be a sentinel loop of bowel from an dynamic ileum and some loop distention but is most common not specified of plain x-rays
• ct and us used
• CT: diffuse enlargement of pancreas and obscured peri pancreatic soft tissue due to swelling

Question 20

Chronic Pancreatitis Radiographic Appearance

Answer 20

• calcification of the pancreas are pathognomonic
• ct and us used
• CT: pancreatic enlargement or atrophy, ductal dilation, calcifications

Question 21

Pancreatic Carcinoma Radiographic Appearance

Answer 21

• us: tumour 2cm or greater, irregular contour, semisolid pattern
• ct: most effective for diagnosis ; tumour mass, ductal dilation and evasion of neighbouring structures (metastases) (staging) decreased attenuation compared to normal pancreatic tissue with contrast enhancement
• BE may show distortion of mucosal pattern and duodenal configuration

Question 21

Pancreatic Carcinoma

Answer 21

• most common pancreatic cancer is adenocarcinoma (cancer that starts in the glands of the lining of the pancreas)
• 60% are located in the head of the pancreas
• har may enlarge, block bile duct and cause obstructional jaundice

Question 22

Diabetes Mellitus

Answer 22

• common endocrine disorder
• pancreas fails to secrete insulin or failure of target cells thought out the body to respond to insulin
• lack of insulin prevents glucose from entering cells which leads to hyperglycemias as glucose stays in blood
• body pH lowers (acidosis) and dehydration can occur (diabetic coma)
• symptoms: polyuria, polydipsia and glycosuria

Question 23

Diabetes Mellitus Radiographic Appearance

Answer 23

• peripheral vessel calcification
• severe osteomyelitis
• neuropathic joints
• gas gangrene (necrotizing infection)
• ischemic gangrene

Question 24

Hypoglycemia

Answer 24

• Low blood sugar
• can occur with diabetic patients if too much insulin, not enough food or too much exercise
• suddenly feel lightheaded, faint, shaky, sweaty
• give them sugar

Question 25

Pneumoperitoneum

Answer 25

• free air in the peritoneal cavity
• often caused by perforation of the GI tract, such as form a perforated peptic or duodenal ulcer or septic infection, penetration injuries or blunt trauma
• peritonitis can occur
• indicates a surgical emergency

Question 26

Pneumoperitoneum Radiographic Appearance

Answer 26

• needs horizontal beam (upright or left decubitus)
• leave pt in position for 10 minutes
  -air under diaphragm appears as sick shaped lucency
• if a lot of free air, may see it in supine position (both inner and outer walls of intestine seen)