Optimization of gas injection in CO2 Angiography

The use of programmable gas injectors has demonstrated how it is necessary to adapt the parameters (gas pressure and flow) in the particular diagnostic context to obtain the best imaging result with minimum radiological exposure. Imaging of a big vascular cavity, or medium size artery or small peripheral artery is a completely different game, which requires different regulations and management of the instruments. In this paper the focus will be on small peripheral arteries imaging (BTK), where the required low injection gas flow interferes with the low hydraulic resistance of the catheter and the wide arterial pressure pulsatility, producing an irregular gas injection, with reflow and pain. To overcome this problem, a calibrated adjunctive resistance in series of the catheter is proposed, with theoretical analysis and optical simulation.