title: Acoustic Cavitation Enhances Focused Ultrasound Ablation with Phase-Shift Inorganic Perfluorohexane Nanoemulsions: An In Vitro Study Using a Clinical Device.
abstract: Purpose. To investigate whether acoustic cavitation could increase the evaporation of a phase-shift inorganic perfluorohexane (PFH) nanoemulsion and enhance high intensity focused ultrasound (HIFU) ablation. Materials and Methods. PFH was encapsulated by mesoporous silica nanocapsule (MSNC) to form a nanometer-sized droplet (MSNC-PFH). It was added to a tissue-mimicking phantom, whereas phosphate buffered saline (PBS) was added as a control (PBS-control). HIFU (P ac = 150 W, t = 5/10 s) exposures were performed in both phantoms with various duty cycles (DC). US images, temperature, and cavitation emissions were recorded during HIFU exposure. HIFU-induced lesions were measured and calculated. Results. Compared to PBS-control, MSNC-PFH nanoemulsion could significantly increase the volume of HIFU-induced lesion (P < 0.01). Peak temperatures were 78.16 ± 5.64°C at a DC of 100%, 70.17 ± 6.43°C at 10%, 53.17 ± 4.54°C at 5%, and 42.00 ± 5.55°C at 2%, respectively. Inertial cavitation was much stronger in the pulsed-HIFU than that in the continuous-wave HIFU exposure. Compared to 100%-DC exposure, the mean volume of lesion induced by 5 s exposure at 10%-DC was significantly larger, but smaller at 2%-DC. Conclusions. MSNC-PFH nanoemulsion can significantly enhance HIFU ablation. Appropriate pulsed-HIFU exposure could significantly increase the volume of lesion and reduce total US energy required for HIFU ablation.
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Lu-Yan
authors.initials: LY
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Jian-Zhong
authors.initials: JZ
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Zong-Gui
authors.initials: ZG
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China.
authors.forename: Jiao
authors.initials: J
authors.lastname: Jiao
authors.affiliation: State Key Laboratory of Ultrasound Engineering in Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, China; HIFU Unit, The Churchill Hospital, Oxford University Hospitals, Headington, Oxford OX3 7LE, UK.
authors.forename: Feng
authors.initials: F
authors.lastname: Wu
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005466:Fluorocarbons / Q000737:chemistry* / Q000528:radiation effects / Q000627:therapeutic use; D005740:Gases / Q000138:chemical synthesis / Q000528:radiation effects; D019220:High-Energy Shock Waves; D057086:High-Intensity Focused Ultrasound Ablation / Q000295:instrumentation* / Q000379:methods*; D066298:In Vitro Techniques; D007287:Inorganic Chemicals / Q000737:chemistry / Q000528:radiation effects / Q000627:therapeutic use; D008422:Materials Testing; D053769:Nanocapsules / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure; D010316:Particle Size; D016896:Treatment Outcome
chemical_list: D005466:Fluorocarbons; D005740:Gases; D007287:Inorganic Chemicals; D053769:Nanocapsules; C078626:perflexane