Foam Fortification: The Effect of Perfluorocarbon Gases on the Stability of Sclerosing Agent Foams.

Purpose: To evaluate the impact of incorporating perfluorocarbons (PFCs), specifically C₃F₈ and C₄F₁₀, on the stability of STS-based foams.

Materials and methods: Tessari's method was employed to generate foams. C₃F₈ and C₄F₁₀ were compared with room air due to their known characteristic as gas vesicle stabilizers. Each trial set encompassed ratios of 1:1.5, 2, 3, and 4 mL of STS-to-gas. Foam decay (1 minus percent foam remaining in syringe) was monitored using a 4K camera over 1 hour, followed by hourly snapshots for 3 hours. All trials were repeated in triplicate. Statistical analysis was carried out via one-way ANOVA and, where appropriate, Student's T-test.

Results: PFC-stabilized foams exhibited greater stability than room air-stabilized foams, with C₄F₁₀ demonstrating the highest stability. Air-stabilized foams fully decayed within 30 minutes, whereas PFCs maintained over 70% foam volume for up to 45 minutes. Notably, a significant decrease in foam stability was observed in the 1:4 ratio of C₃F₈ between 60 to 180 minutes, a decline not seen in C₄F₁₀ foams (p < 0.001). While increasing the STS-to-room air ratio diminished foam stability, it enhanced stability in PFC-stabilized foams. Specifically, the 1:4 STS-to-PFC ratio sustained approximately 15% more foam than the 1:1.5 ratio over 180 minutes, aside from the substantial decrease in C₃F₈ foams. These findings suggest PFCs may improve the stability of sclerosing foams.

Conclusion: C₃F₈ and C₄F₁₀ showed greater stability with STS compared to room air, and C₄F₁₀ exhibited better stability over time than C₃F₈.