Computer-based liver volumetry in the liver perfusion simulator.

Area of Science:

• Surgical simulation and medical device development.
• Hepatic imaging and volumetric analysis.
• Physiological modeling of liver function.

Background:

• Accurate preoperative liver volume calculation is critical for liver surgery and transplantation.
• Current CT/MRI methods have significant estimation errors (1.2%-36%) and lack segmental accuracy.
• Limited data exists on the accuracy of liver volumetry at the segmental level.

Purpose of the Study:

• To validate arterial and portal venous flow rates in a liver perfusion simulator.
• To assess liver volumetry, including segmental analysis, using the simulator.
• To compare simulator measurements with in vivo porcine model data.

Main Methods:

• In vivo and ex vivo measurements of liver volume and flow rates in 10 pigs.
• CT scans for liver and lobe volume calculation (water displacement vs. computer-assisted).
• Plastic reconstruction of the right lateral lobe for volume validation.

Main Results:

• Simulator achieved arterial/portal venous flow rates comparable to in vivo measurements.
• Mean liver volume difference between in vivo and ex vivo was 10.3%.
• Simulator showed a 2.8% mean deviation in volume calculation (computer vs. water displacement).
• Heidelberg algorithm achieved 97.7% accuracy for segmental liver volumetry.

Conclusions:

• The liver perfusion simulator is highly effective for liver perfusion and volumetry studies.
• The simulator is a valuable tool for surgical training and intervention practice.
• This technology offers improved accuracy for liver volume assessment, particularly segmentally.