高功率聚焦超声高温破坏肝肿瘤的影像学检测

Imaging Characteristics of Rabbit Liver Tumour Destruction Induced by High Intensity Focused Ultrasound

本文报告彩超、ＣＴ和ＭＲＩ观察高功率聚焦超声（ＨＩＦＵ）破坏兔肝肿瘤前、后影像特征变化，旨在探讨这三种影像学技术检测ＨＩＦＵ疗效的可行性。１０只兔肝肿瘤模型由肝内注射Ｆｒｅｕｎｄ完全佐剂，一周后形成炎性假瘤结节制成。ＨＩＦＵ治疗参数采用频率１．１ＭＨｚ，功率５００Ｗ／ｃｍ２，连续超声波照射时间２０秒。结果显示：彩超能有效检测ＨＩＦＵ破坏肝肿瘤疗效。经ＨＩＦＵ照射后，表现为强回声病灶变为低回声，且Ｄｏｐｐｌｅｒ血流消失，２４ｈ后病灶边缘出现强回声带。这些特征性变化与病理改变相一致。

High intensity focused ultrasound (HIFU) is a new technique which can induce selective tumour destruction in the body without causing damage to the intervening abdominal wall. This study observed colour Doppler Image computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of HIFU ablated liver tumour in an attempt to asesess the possibility of using these imaging methods to monitor the therapeutic results. 10 rabbit liver tumour models were established by injection of Freund's complete adjuvant into the lobe of liver; a well formed inflammatory granuloma was produced one week later. HIFU was applied by single shot of 1.1 MHz at an intensity of 500 W/cm 2 with continuous exposure duration of 20s. The results showed that colour sonography was a useful modality for monitoring sonoablated liver tumour which exhibited hypoechoic lesion with loss of Doppler signal. An echogenic rim appeared 24h later. These sonographic patterns correlated well with the pathologic findings in terms of size and histologic changes of the lesion. However, CT and MRI revealed no characteristic changes after HIFU treatment.