Liver Scan

Indications

• Assessment of liver disease.
• Assessment of liver/spleen shape, size and position
• Detection of focal leisions
• Detection of space occupying leisions.
• Evaluate hepatobiliary ducts

Principle  

The hepatic polygonal cells rapidly remove the radiopharmaceutical from the bloodstream and adds it to the bile that normally flows through the network of small tubes (bile ducts) then releases the tracer into the beginning of the small intestine (duodenum).

Patient Preparation

Mild sedation as needed

Equipment

Large field of view gamma camera  with low energy all purpose collimator and a 25% window.

Radiopharmaceutical

99mTc disofenin or other Tc-IDA  iminodiacetic acid derivatives.

Acquisition Protocol

• Initial sequential dynamic images are acquired at 5 seconds per frame for two minutes. These can be viewed as individual frames or a single composite image.
• Acquire 500,000 counts per image, motion corrected if available
• Dorsal ventral views are acquired at 5, 10, 15, 30 and 60 minutes post injection.
• Additional lateral views are acquired periodically throughout the scan.
• Delayed images are to be acquired at 2-4 hours.
• If the intestinal tract is not visualized by 4 hours further imaging at 24 hours should be obtained

Interpretation

Normally there is swift and homogeneous liver uptake and  excretion into the small bowel with visualization of the biliary duct system within 60 minutes.

If bowel is not visualized within 60 min, return the horse to the stall and allow him to eat. Acquire images later 2, 4, and 8 hours.  An image at 24 hours may be helpful if the bowel is still not visible at 8 hours, however, count statistics may not be adequate to acquire an image in a timely manner.