IS FlowMap, a novel tool to examine blood flow changes induced by flow diverter stent treatment: initial experiences with pipeline cases.

BACKGROUND

Intracranial aneurysm flow diverting stents are a new endovascular treatment option for wide neck and large/giant aneurysms. Since August 2011, our center has integrated flow diverting stents into aneurysm treatment management. To further understand the effects of flow diverting stents, we developed the intracranial stent flow mapping program, which allows detailed, case by case, examination and comparison of blood flow changes within an aneurysm before and after stent treatment.

METHODS

The Intracranial Stent Flow Mapping program (IS FlowMap) utilizes algorithms detecting movement changes between consecutive images. Sequences of catheter angiograms capturing the movement of injected contrast were used to map flow patterns and examine aneurysmal flow before and after stent implantation.

RESULTS

A pilot study of this new technique in flow diverter (FD) stent treated aneurysms was performed. Four clinical aneurysms (two wide neck and two giant aneurysms) were analyzed by IS FlowMap. The characteristics of redirected flow in cases treated with one stent or two overlapping stents in the reconstructed vessels are presented. Distinct differences in flow impingement on the aneurysm wall, aneurysmal inflow, and flow circulation before and after FD stent treatment were found.

CONCLUSIONS

We present a novel approach to map blood flow motion within aneurysms and have shown the feasibility of the technique in clinical aneurysms. This new technology can help monitor flow changes induced by stents and study the relationship between the modified flow and treatment outcome.