Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Zhunan, Taiwan.
Department of Neurology, National Cheng Kung University Hospital, Tainan, Taiwan.
Br J Anaesth. 2015 May;114(5):840-6. doi: 10.1093/bja/aeu443. Epub 2015 Jan 16.
Nerve conduction block using high-intensity focused ultrasound (HIFU) has been conducted with nerves of mixed fibres in normal animal models. This study tested the feasibility and safety of HIFU for sensory nerve conduction block in diabetic neuropathic nerves to determine its potential for pain relief.
Diabetes was induced in Sprague-Dawley rats using streptozotocin, and HIFU at 2.68 MHz was used for the block. This study consisted of two sections, in vitro and in vivo. For the in vitro experiments, the entire contiguous sciatic-sural nerves were obtained. Compound action potentials and sensory action potentials were recorded in the sciatic and sural nerves, respectively. For the in vivo experiments, compound muscle action potentials (CMAPs) were recorded from the gastrocnemius muscles. All data were expressed as median (range).
The in vitro results showed that HIFU temporarily inhibited sensory action potentials of the control and diabetic rat nerves to 33.9 (8.2) and 14.0 (10.7)% of the baseline values, respectively, whereas the compound action potentials were suppressed to 53.6 (8.4) and 76.2 (7.5)% of baseline, respectively. The in vivo results showed that HIFU acutely blocked CMAPs to 32.9 (12.6) and 19.9 (10.9)% of baseline in control and diabetic rat nerves, respectively. Measurements of CMAPs and histological exanmination were used for indirect assessment of the safety of the HIFU technique.
High-intensity focused ultrasound safely and reversibly suppressed nerve conduction in diabetic rat nerves when the stimulation parameters were appropriate. The results suggest that HIFU may have potential to block sensory nerves reversibly and provide peripheral pain relief.
在正常动物模型中，高强度聚焦超声（HIFU）已用于混合纤维神经的神经传导阻滞。本研究测试了 HIFU 用于糖尿病神经病变神经感觉神经传导阻滞的可行性和安全性，以确定其缓解疼痛的潜力。
链脲佐菌素诱导 Sprague-Dawley 大鼠糖尿病，使用 2.68MHz 的 HIFU 进行阻断。本研究分为体外和体内两部分。在体外实验中，获得了整个连续的坐骨-跗骨神经。分别在坐骨和跗骨神经中记录复合动作电位和感觉动作电位。在体内实验中，从腓肠肌记录复合肌肉动作电位（CMAPs）。所有数据均表示为中位数（范围）。
体外结果显示，HIFU 暂时抑制了对照和糖尿病大鼠神经的感觉动作电位，分别为基础值的 33.9（8.2）%和 14.0（10.7）%，而复合动作电位分别抑制至基础值的 53.6（8.4）%和 76.2（7.5）%。体内结果显示，HIFU 急性阻断 CMAPs，分别为对照和糖尿病大鼠神经基础值的 32.9（12.6）%和 19.9（10.9）%。CMAPs 的测量和组织学检查用于间接评估 HIFU 技术的安全性。
当刺激参数适当时，高强度聚焦超声安全可逆地抑制了糖尿病大鼠神经的神经传导。结果表明，HIFU 可能具有可逆阻断感觉神经并提供外周止痛的潜力。
