Liver Ultrasound Indications

What is the main indication for a single-phase contrast-enhanced computed tomography of the liver?

Staging known primary or secondary malignancy

Why is oral contrast sometimes not necessary in liver CT imaging?

When only the liver parenchyma is being investigated

What is the ideal slice thickness for a routine liver CT imaging?

Less than 5 mm

When should contrast-enhanced CT of the liver be performed during a helical/multislice CT scan?

During peak parenchymal enhancement Signup and view all the answers

Which of the following is a contraindication to undergoing a contrast-enhanced CT of the liver?

Pregnancy Signup and view all the answers

What imaging technique would be most suitable to assess a patient with suspected portal hypertension?

Multiphasic contrast-enhanced CT Signup and view all the answers

In liver imaging, what is the purpose of assessing patients with surgical shunts or TIPS procedures?

To evaluate patency and function of shunts Signup and view all the answers

What symptom might prompt a healthcare provider to consider a contrast-enhanced CT of the liver?

Right upper-quadrant pain Signup and view all the answers

During what phase does single-phase contrast-enhanced computed tomography image the liver?

Portal phase Signup and view all the answers

What is the benefit of using multiphasic contrast-enhanced computed tomography for liver imaging compared to single-phase imaging?

Better characterization of liver lesions Signup and view all the answers

What is the main reason that liver tumors enhance strongly during the arterial phase?

Due to receiving blood supply from the hepatic artery Signup and view all the answers

Why is it advisable to perform an arterial phase scan in addition to a portal venous phase CT scan for patients with suspected hypervascular primary or secondary liver tumors?

To enhance visualization of liver tumors that are most conspicuous during the early-phase arterial scanning Signup and view all the answers

What is the appropriate imaging protocol for suspected hepatocellular cancer?

Triple phase (early and late arterial with portal venous phase) Signup and view all the answers

Why might some centers characterize primary liver tumors using a quadruple-phase scan?

To include arterial, portal, and delayed scans Signup and view all the answers

In CT cholangiography, what is done to opacify the biliary tree?

Intravenous administration of a cholangiographic agent Signup and view all the answers

What are some common indications for performing computed tomography of the pancreas?

Acute pancreatitis and its complications along with chronic pancreatitis and its complications Signup and view all the answers

Why is positive contrast (iodinated) contraindicated if CT angiography is to be performed during imaging of the pancreas?

To avoid opacification of distal bowel loops Signup and view all the answers

Why is non-contrast-enhanced examination no longer indicated in initial scans for identifying calcifications in pancreatic imaging?

"Calcifications are now evident on vascular phases" Signup and view all the answers

"What is the main reason for reconstructing images at different thicknesses in the pancreatic and portal venous phases?"

"To optimize contrast differentiation between adenocarcinoma and normal pancreatic tissue" Signup and view all the answers

What is the main purpose of performing intraoperative cholangiography?

To avoid surgical exploration of the common bile duct Signup and view all the answers

What is a common occurrence during intraoperative cholangiography that may be relieved by glucagon, propantheline, or amyl nitrite?

Spasm of the sphincter of Oddi Signup and view all the answers

According to Le Quesne, which of the following is NOT a criterion for a normal operative choledochogram?

Presence of filling defects Signup and view all the answers

What is the recommended volume of contrast medium for intraoperative cholangiography?

10 mL Signup and view all the answers

Why is preoperative MRCP and/or EUS mentioned in relation to intraoperative cholangiography?

To avoid the need for surgical exploration in some centers Signup and view all the answers

What is the most appropriate indication for performing percutaneous transhepatic cholangiography?

Relief of obstructive jaundice Signup and view all the answers

What should be checked and corrected if necessary before performing percutaneous transhepatic cholangiography?

Hemoglobin, prothrombin time, and platelets Signup and view all the answers

What technique is used to insert the Chiba needle during percutaneous transhepatic cholangiography?

Insertion during suspended respiration Signup and view all the answers

What might happen if contrast medium is injected under high pressure into an obstructed biliary tract?

Increased risk of septicemia Signup and view all the answers

When is the ideal time to perform a percutaneous transhepatic cholangiography?

On the 10th postoperative day Signup and view all the answers

What is the main purpose of a wide-channelled endoscope in the context described?

To deploy metal biliary stents Signup and view all the answers

In the context of transhepatic puncture, what is the significance of a 22G Chiba needle?

To enable access into the bile ducts Signup and view all the answers

What is a common post-stent deployment step mentioned in the text?

Regular flushing of the catheter with saline Signup and view all the answers

What is a complication mentioned that can occur due to the passage of a guidewire?

Perforation of bile duct above the stricture Signup and view all the answers

What is a specific indication for the Percutaneous Extraction of Retained Biliary Calculi using the Burhenne Technique?

Retained biliary calculi seen on T-tube cholangiogram Signup and view all the answers

What is the main reason for avoiding excessive parenchymal injection during percutaneous transhepatic cholangiography (PTC)?

It results in opacification of intrahepatic lymphatics Signup and view all the answers

What is the recommended action if a duct is not entered at the first attempt during PTC?

Withdraw the needle tip and direct it more cranially, caudally, anteriorly, or posteriorly Signup and view all the answers

What is a possible complication of filling an obstructed duct system beyond capacity during PTC?

Septic shock due to overfilling Signup and view all the answers

When is a further image recommended after tilting the patient towards the erect position during PTC?

After an initial image showing an obstruction at the porta hepatis level Signup and view all the answers

What is the primary cause of septic shock during PTC according to the text?

The presence of choledocholithiasis leading to infected bile Signup and view all the answers