Optical monitoring of ultrasound-induced bioeffects in glass catfish
Optical monitoring of ultrasound-induced bioeffects in glass catfish
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DOI：
10.1016/j.ultrasmedbio.2003.08.005
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发表时间：
2004-01-01
影响因子：
2.9
通讯作者：
Hynynen, K
中科院分区：
文献类型：
--
作者：
Maruvada, S;Hynynen, K
本研究是研究治疗性超声（US）对光学透明鱼血管的体内作用。尽管许多研究人员利用遥感方法（即测量气泡振荡引起的声发射）在体内描述了空化现象，但很少有人对空化引起的损伤进行直接观察。麻醉后的玻璃鲶鱼呈光学透明，注射造影剂Optison(R)，然后在0.5-10 MPa（峰值负压）的压力下进行失音。实验中使用了两个聚焦换能器，覆盖0.7-3.3 MHz的频率范围。脉冲时间分别为100、10、1、0.1和0.01 ms，脉冲重复频率（PRF）为1 Hz。在特定压力水平下，一次超声的总长度为20秒。倒置显微镜结合数码相机和视频监视器，在200倍放大镜下光学监测和记录US与麻醉鱼尾部血管的相互作用。在各个压力水平下，对爆破超声效果进行了可视化分析。对于1.091 mhz的超声波，由于US相互作用而发生的第一类损伤是对构成鱼尾的软骨杆的结构性损伤，其特征是杆的衬里解体。在100毫秒、10毫秒、1毫秒和100毫秒的声波中，杆状细胞分别从3.5 MPa、3.1 MPa、4.1 MPa和5.5 MPa开始受到损伤。在100毫秒、10毫秒和1毫秒的超声阈值分别为3.8 MPa、3.8 MPa和5.3 MPa时，在鱼的血管中观察到大气泡的形成。在100 μ s超声期间未观察到气泡形成或出血。气泡的形成总是伴随着气泡周围区域棒损伤的增加。在1.091 MHz时，三种脉冲持续时间分别在4.1 MPa、4.1 MPa和6.1 MPa处观察到点状出血阈值。损伤阈值在0.747-MHz时最低：棒损伤阈值为2.6 MPa，气泡形成阈值为3.7 MPa，出血阈值为2.4 MPa。(C) 2004年世界超声医学生物学联合会。
This study is an investigation of the therapeutic ultrasound (US) effects on the blood vessels of optically transparent fish in vivo. Although many investigators have characterized cavitation in vivo using remote-sensing methods (i.e., measuring the acoustic emissions caused by oscillating bubbles) very few have made direct observations of cavitation-induced damage. Anesthetized glass catfish, which are optically transparent, was injected with the contrast agent, Optison(R), and then insonified at pressures that ranged from 0.5-10 MPa (peak negative pressures). Two focused transducers were used in these experiments to cover a frequency range of 0.7-3.3 MHz. Sonications were pulsed with pulse durations of 100, 10, 1, 0.1 and 0.01 ms and a pulse repetition frequency (PRF) of 1 Hz. The entire length of one sonication at a specific pressure level was 20 s. An inverted microscope combined with a digital camera and video monitor were used optically to monitor and record US interaction with the blood vessels in the tail of the anesthetized fish at 200 X magnification. The effects of the burst sonication were analyzed visually at each pressure level. For the 1.091-MHz sonications, the first type of damage that occurred due to the US interaction was structural damage to the cartilage rods that comprise the tail of the fish, and was characterized by a disintegration of the lining of the rod. Damage to the rods occurred, starting at 3.5 MPa, 3.1 MPa, 4.1 MPa and 5.5 MPa for the 100-ms, 10-ms, 1-ms and 100-mus sonications, respectively. The formation of large gas bubbles was observed in the blood vessels of the fish at threshold values of 3.8 MPa, 3.8 MPa and 5.3 MPa, for the 100-ms, 10-ms and 1-ms sonications, respectively. Neither gas bubble formation nor hemorrhaging was observed during 100-mus sonications. Bubble formation was always accompanied by an increase of damage to the rods at the area surrounding the bubble. At 1.091 MHz, petechial hemorrhage thresholds were observed at 4.1 MPa, 4.1 MPa and 6.1 MPa, respectively, for the three pulse durations. The thresholds for damage were the lowest for the 0.747-MHz sonications: they were 2.6 MPa for damage to the rods, 3.7 MPa for gas bubble formation and 2.4 MPa for hemorrhaging. (C) 2004 World Federation for Ultrasound in Medicine Biology.