PDF(Pubmed)
Abstract：
BACKGROUND: In dermatology, inflammatory skin conditions impose a substantial burden worldwide, with existing therapies showing limited efficacy and side effects. This report aims to compare a novel immunological activation induced by hyperthermic 20 MHz high intensity focused ultrasound (HIFU) with conventional cryotherapy. The bioeffects from the two methods are initially investigated by numerical models, and subsequently compared to clinical observations after treatment of a patient with the inflammatory disease granuloma annulare (GA).
METHODS: Clinical responses to moderate energy HIFU and cryotherapy were analysed using numerical models. HIFU-induced pressure and heat transfer were calculated, and a three-layer finite element model simulated temperature distribution and necrotic volume in the skin. Model output was compared to 22 lesions treated with HIFU and 10 with cryotherapy in a patient with GA.
RESULTS: Cryotherapy produced a necrotic volume of 138.5 mm3 at - 92.7 °C. HIFU at 0.3-0.6 J/exposure and focal depths of 0.8 or 1.3 mm generated necrotic volumes up to only 15.99 mm3 at temperatures of 68.3-81.2 °C. HIFU achieved full or partial resolution in all treated areas, confirming its hyperthermic immunological activation effect, while cryotherapy also resolved lesions but led to scarring and dyspigmentation.
CONCLUSIONS: Hyperthermic immunological activation of 20 MHz HIFU shows promise for treating inflammatory skin conditions as exemplified by GA. Numerical models demonstrate minimal skin necrosis compared to cryotherapy. Suggested optimal HIFU parameters are 1.3 mm focal depth, 0.4-0.5 J/exposure, 1 mm spacing, and 1 mm margin. Further studies on GA and other inflammatory diseases are recommended.
METHODS: Clinical responses to moderate energy HIFU and cryotherapy were analysed using numerical models. HIFU-induced pressure and heat transfer were calculated, and a three-layer finite element model simulated temperature distribution and necrotic volume in the skin. Model output was compared to 22 lesions treated with HIFU and 10 with cryotherapy in a patient with GA.
RESULTS: Cryotherapy produced a necrotic volume of 138.5 mm3 at - 92.7 °C. HIFU at 0.3-0.6 J/exposure and focal depths of 0.8 or 1.3 mm generated necrotic volumes up to only 15.99 mm3 at temperatures of 68.3-81.2 °C. HIFU achieved full or partial resolution in all treated areas, confirming its hyperthermic immunological activation effect, while cryotherapy also resolved lesions but led to scarring and dyspigmentation.
CONCLUSIONS: Hyperthermic immunological activation of 20 MHz HIFU shows promise for treating inflammatory skin conditions as exemplified by GA. Numerical models demonstrate minimal skin necrosis compared to cryotherapy. Suggested optimal HIFU parameters are 1.3 mm focal depth, 0.4-0.5 J/exposure, 1 mm spacing, and 1 mm margin. Further studies on GA and other inflammatory diseases are recommended.
摘要：
背景：在皮肤科，炎症性皮肤病在全球范围内造成了沉重负担，现有疗法显示有限的疗效和副作用。本报告旨在比较20MHz高温高强度聚焦超声（HIFU）与常规冷冻疗法引起的新型免疫激活。通过数值模型初步研究了两种方法的生物效应，并随后与患有炎症性疾病环状肉芽肿（GA）的患者治疗后的临床观察结果进行比较。
方法：使用数值模型分析了中等能量HIFU和冷冻疗法的临床反应。计算了HIFU引起的压力和传热，和三层有限元模型模拟皮肤中的温度分布和坏死体积。将模型输出与在患有GA的患者中用HIFU治疗的22个病变和用冷冻疗法治疗的10个病变进行比较。
结果：冷冻疗法在-92.7°C时产生138.5mm3的坏死体积。HIFU在0.3-0.6J/曝光和0.8或1.3mm的焦深下产生的坏死体积在68.3-81.2°C的温度下仅高达15.99mm3。HIFU在所有治疗区域实现了全部或部分分辨率，证实了它的高热免疫激活作用，而冷冻疗法也解决了病变，但导致疤痕和色素沉着。
结论:20MHzHIFU的高热免疫活化显示出治疗炎性皮肤病症的希望,如GA所例示。与冷冻疗法相比，数值模型显示出最小的皮肤坏死。建议的最佳HIFU参数为1.3mm焦深，0.4-0.5J/曝光,1mm间距,和1毫米的边缘。建议对GA和其他炎性疾病进行进一步研究。
方法：使用数值模型分析了中等能量HIFU和冷冻疗法的临床反应。计算了HIFU引起的压力和传热，和三层有限元模型模拟皮肤中的温度分布和坏死体积。将模型输出与在患有GA的患者中用HIFU治疗的22个病变和用冷冻疗法治疗的10个病变进行比较。
结果：冷冻疗法在-92.7°C时产生138.5mm3的坏死体积。HIFU在0.3-0.6J/曝光和0.8或1.3mm的焦深下产生的坏死体积在68.3-81.2°C的温度下仅高达15.99mm3。HIFU在所有治疗区域实现了全部或部分分辨率，证实了它的高热免疫激活作用，而冷冻疗法也解决了病变，但导致疤痕和色素沉着。
结论:20MHzHIFU的高热免疫活化显示出治疗炎性皮肤病症的希望,如GA所例示。与冷冻疗法相比，数值模型显示出最小的皮肤坏死。建议的最佳HIFU参数为1.3mm焦深，0.4-0.5J/曝光,1mm间距,和1毫米的边缘。建议对GA和其他炎性疾病进行进一步研究。
