From the *Department of Anesthesiology and Critical Care Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY; †Department of Anesthesiology, David Geffen School of Medicine at UCLA, Los Angeles, CA; ‡Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY; §Department of Comparative Medicine, Medical University of South Carolina, Charleston, SC; and ∥Center of Comparative Medicine and Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY.
Reg Anesth Pain Med. 2014 Jan-Feb;39(1):26-30. doi: 10.1097/AAP.0000000000000028.
High-intensity focused ultrasound (HIFU) is a noninvasive thermal ablation technique. High-intensity focused ultrasound has been used in small-animal models to lesion neural tissue selectively. This study aimed to evaluate the efficacy of HIFU in a large-animal model for ablation of nerves similar in size to human nerves.
Twelve acute magnetic resonance-guided HIFU ablation lesions were created in intercostal nerves in a swine model. In a second pig, as a control, 4 radiofrequency ablation and 4 alcohol lesions were performed on intercostal nerves under ultrasound guidance. Preprocedural and postprocedural magnetic resonance imaging was then performed to evaluate radiologically the lesion size created by HIFU. Animals were euthanized 1 hour postprocedure, and necropsy was performed to collect tissue samples for histopathologic analysis.
On gross and histological examination of the intercostal nerve, acute HIFU nerve lesions showed evidence of well-demarcated, acute, focally extensive thermal necrosis. Four intercostal nerves ablated with HIFU were sent for histopathologic analysis, with 2 of 4 lesions showing pathologic damage to the intercostal nerve. Similar results were shown with radiofrequency ablation technique, whereas the intercostal nerves appeared histologically intact with alcohol ablation.
High-intensity focused ultrasound may be used as a noninvasive neurolytic technique in swine. High-intensity focused ultrasound may have potential as a neuroablation technique for patients with chronic and cancer pain.
高强度聚焦超声（HIFU）是一种非侵入性的热消融技术。高强度聚焦超声已被用于小动物模型中，以选择性地损伤神经组织。本研究旨在评估高强度聚焦超声在类似人神经大小的大动物模型中用于消融神经的疗效。
在猪模型中，通过磁共振引导的 12 个肋间神经高强度聚焦超声消融病变。在第二头猪中，作为对照，在超声引导下对肋间神经进行 4 次射频消融和 4 次酒精消融。然后进行术前和术后磁共振成像，以评估 HIFU 产生的病变大小的放射学表现。动物在术后 1 小时安乐死，进行尸检以收集组织样本进行组织病理学分析。
在肋间神经的大体和组织学检查中，急性 HIFU 神经病变显示出界限清楚、急性、局灶性广泛热坏死的证据。对 4 根经 HIFU 消融的肋间神经进行了组织病理学分析，其中 2 根显示出肋间神经的病理损伤。射频消融技术也显示出类似的结果，而酒精消融的肋间神经在组织学上似乎完整无损。
高强度聚焦超声可作为猪的非侵入性神经溶解技术。高强度聚焦超声可能成为治疗慢性和癌症疼痛患者的神经消融技术。
