CT of the abdomen

The liver IV contrast is important in detecting focal masses. Biphasic examination is an important tool in liver investigation. Dynamic scan are very useful liver scanning, it involves multiple repeat scans of the same level or several selected levels to see enhancement patterns.

The liver With multislice CT very thin slices are produced 2.5 mm, which allow better detection of liver lesions. CT is as accurate as U/S in demonstrating intra hepatic and extra hepatic bile ducts in jaundiced patients.

The spleen CT is the best method for screening for splenic injury after abdominal trauma. It is useful in detecting neoplasm.

Retro peritoneum Pancreas: CT is the best method in imaging the whole pancreas. CT is useful in detecting in doubt pancreatitis. Useful in chronic pancreatitis to detect pancreatic calcification and pancreatic ductal dilatation.

Kidneys Investigation of renal colic. Detecting stones, size and location CT is capable of distinguishing a cystic from a solid mass. Useful in staging tumours.

Adrenal gland CT can easily confirm a normal adrenal gland It is the best method to investigate tiny hyperfunction. Useful in detecting tumors. Useful in detecting any metastasis.

Others CT is very useful in detecting any lymphoma or metastaic lymph nodes. CT is the abdominal imaging method of choice because of the bowel gas, fat and bony structures that can obstruct a sonogram. CT is most useful in sizing and following up on abdominal aortic aneurysms, it is also useful to detect any complications such as rupture of an aneurysm. CT is very useful in detecting the extent of a tumor and its relationship with normal structure.

Protocols Patient is scanned supine and may be scanned prone for biopsy. Some images are obtained without contrast medium: Calcific masses or renal calculi. To localize hepatic lesions before rapid contrast enhancement.

Contrast medium enhancement of the liver There are several factors which are important in diagnosing the liver: The liver has a dual blood supply, from the hepatic artery and the portal vein. Arterial flow occurs earlier than portal inflow. Most neoplasm's receive their blood primarily from the hepatic artery and normal hepatocytes primarily receive their blood from the portal vein.

Biphasic examination of the liver 1. Arterial phase: 20-30 seconds Best visualize highly vascular lesions, both benign and malignant such as hepatocellular carcinoma, hypervascular metastases. Venous phase: 60-80 seconds Best suited for studying hypovascular lesions such as colonic metastasis.

Biphasic examination of the pancreas Arterial phase: 5 second Optimally enhances the arteries and pancreatic parynchyma allowing visualization of small hypodense or hyperdence masses and in demonstrating any vascular masses. Venous phase: 60 seconds

Liver metastases from colon cancer

Infracted kidney Renal cell carcinoma

Hepatitis C w/cirrhosis

Splenic infarction

Splenic calcification

Normal colon

Normal colon

Cancer Cancer in cecum