Relationship between aneurysm occlusion and flow diverting device oversizing in a rabbit model

Area of Science:

• Endovascular therapy
• Cerebrovascular disease
• Medical device engineering

Background:

• Flow diverter pore density is believed to depend on device-artery size matching.
• Understanding this relationship is crucial for effective aneurysm treatment.

Purpose of the Study:

• To investigate the correlation between flow diverter device sizing, metal coverage, and aneurysm occlusion.
• To evaluate these factors in a rabbit aneurysm model.

Main Methods:

• Rabbit saccular aneurysms were treated with flow diverters (iso-sized, 0.5mm oversized, 1.0mm oversized).
• Aneurysm occlusion was assessed angiographically after 8 weeks.
• Metal coverage and pore density at the aneurysm ostium were calculated and correlated with occlusion.

Main Results:

• No significant differences in aneurysm occlusion were observed among the different device sizing groups.
• Neither metal coverage nor pore density varied significantly between groups.
• Aneurysm occlusion showed an inverse correlation with the ostium diameter, independent of device size.

Conclusions:

• Flow diverter device sizing alone does not reliably predict pore density or metal coverage in this model.
• Aneurysm occlusion is primarily influenced by the ostium diameter, not by metal coverage or pore density.
• These findings suggest ostium diameter is a key factor in flow diverter treatment outcomes.