Validating the minimally invasive balloon removal technique in fetal endoscopic tracheal occlusion for congenital diaphragmatic hernia using high-intensity focused ultrasound

Abstract

The current methods of removing the tracheal occlusion balloon in fetal endoscopic tracheal occlusion （FETO） for congenital diaphragmatic hernia （CDH） are significantly invasive for both the mother and the fetus. This study explores the validity of a novel approach combining high-intensity focused ultrasound （HIFU） and limonene emulsion to achieve noninvasive balloon removal after FETO. A FETO balloon model using natural rubber injected with 0.3ml limonene emulsion was subjected to HIFU irradiation at five output voltages （240, 200, 160, 120, and 80Vpp） across 25 experiments. Using a high-speed camera, the model was observed for balloon rupture or shrinkage. Higher HIFU output power frequently led to rupture patterns. Further regression analysis revealed that higher output power tended to reduce the rupture time; however, it was statistically nonsignificant （p＝0.1361）. Cavitation and emulsion collapse observed using the high-speed camera confirmed that the rupture mechanism was attributable to the interaction between limonene and latex and the physical effects of HIFU. Limonene emulsion with latex subjected to HIFU can be used as a noninvasive method for balloon removal after FETO. Further research is warranted to clinically validate these results and identify the optimal HIFU output power for adequate balloon collapse.