When pigs fly
Justine Cadet, Executive Editor
When researchers undertake porcine studies in the preclinical setting, it typically indicates a final step in the research process, which may soon after result in a new treatment method for patients.

This potential next step to human treatment was on the minds of Dutch researchers, who recently undertook a clinical study involving six pigs with normal livers.

The researchers noted that they aimed to “make the method as simple as possible with the prospect of future application to clinical studies.” To this end, they examined the possibility of using a three-minute data acquisition and a model-derived dual input calculated from measurements of radioactivity concentrations in a peripheral artery.

The subjects underwent dynamic PET of the liver with three different PET tracers—18F-FDG, 11C-MG or 18F-FDGal. Simultaneous measurements of time also were assessed; activity curves in blood were sampled from a femoral artery and the portal vein; and blood flow rates were measured in the hepatic artery and portal vein by transit-time flow meters.

The researchers developed this simplified method for quantification of hepatic blood perfusion using three-minute dynamic 18F-FDG PET or 11C-MG PET with blood sampling from only a peripheral artery.

Keiding et al compared this method with a 60-minute acquisition scan, and computed two input functions: a measured dual input and a model-derived dual input, the latter with the PV time-activity curve estimated from the measured arterial time-activity curve and a previously validated one-parametric portal vein model.

Based on their results, Keiding and colleagues concluded that they had developed and validated a simplified method to quantify and image blood perfusion in normal pig livers using a three-minute dynamic PET acquisition after intravenous injection of 11C-MG or 18F-FDG.

Also, the “similarity between the splanchnic circulation in humans and pigs indicates promise for transfer to humans, and moreover, the three-minute perfusion measurement can become an integrated part of a routine clinical 18F-FDG PET/CT examination without additional tracer administration and radiation burden to the patient,” they concluded.

Please let us know about any end-stage preclinical research that you or your colleagues are conducting.

Justine Cadet