Weaver Stephanie L, Demchak Timothy J, Stone Marcus B, Brucker Jody B, Burr Phillip O
Marketing Representative, OrthoIndy, Indianapolis, IN 47809, USA.
J Orthop Sports Phys Ther. 2006 May;36(5):320-5. doi: 10.2519/jospt.2006.2157.
A 3 x 2 repeated-measures design was used. The independent variables were transducer velocity (2-3 cm/s, 4-5 cm/s, and 7-8 cm/s) and time (pretreatment and posttreatment).
To determine if transducer velocity of a 1-MHz ultrasound treatment affects intramuscular tissue temperature.
Most authors advocate ultrasound transducer velocities of 2 to 4 cm/s within an area of 2 to 3 times the effective radiating area or 2 times the size of the transducer head. However, a much faster rate of application (approximately 7-8 cm/s) is often observed in clinical settings.
Eleven healthy screened volunteers (9 males, 2 females; mean +/- SD age, 22.6 +/- 1.7 years; mean +/- SD height, 175.7 +/- 13.7 cm; mean +/- SD body mass, 82.5 +/- 19.5 kg) were randomly assigned to a treatment order with all conditions administered during a single testing session. Each transducer velocity condition was administered for 10 minutes, using 1-MHz ultrasound with a 100% continuous duty cycle at an intensity of 1.5 W/cm2 over an area twice the size of the transducer head. After the first treatment, the 2 remaining subsequent velocity conditions were administered after the intramuscular temperature returned to within +/- 0.3 degrees C of the initial pretreatment temperature for 5 minutes. The dependent variable was left triceps surae muscle temperature measured at 3 cm below one half the measured skinfold thickness.
Temperature increase across the 3 velocities was within 0.4 degrees C (F2.20 = 0.07, P = .93). Posttreatment values (mean +/- SD) ranged from 42.7 degrees C +/- 2.3 degrees C for the slowest velocity to 43.1 degrees C +/- 1.4 degrees C for the fastest velocity. Temperature increase was significant for time (F1.01 = 155.68, P<.00001), increasing from 37.8 degrees C +/- 0.8 degrees C pretreatment to 42.9 degrees C +/- 1.9 degrees C after treatment.
Very similar intramuscular temperature increases can be observed among ultrasound treatments (10-minute duration, 1-MHz frequency, 100% continuous duty cycle, 1.5 W/cm2 intensity, within an area twice the size of the transducer head), with transducer velocities of 2 to 3, 4 to 5, and 7 to 8 cm/s.
采用3×2重复测量设计。自变量为换能器速度（2 - 3厘米/秒、4 - 5厘米/秒和7 - 8厘米/秒）和时间（治疗前和治疗后）。
确定1兆赫超声治疗的换能器速度是否会影响肌肉组织温度。
大多数作者主张在有效辐射面积的2至3倍或换能器头部尺寸的2倍范围内，超声换能器速度为2至4厘米/秒。然而，在临床环境中经常观察到更快的应用速度（约7 - 8厘米/秒）。
11名经过健康筛查的志愿者（9名男性，2名女性；平均±标准差年龄，22.6±1.7岁；平均±标准差身高，175.7±13.7厘米；平均±标准差体重，82.5±19.5千克）被随机分配到治疗顺序，所有条件在单次测试期间进行。每个换能器速度条件持续10分钟，使用1兆赫超声，100%连续占空比，强度为1.5瓦/平方厘米，作用于换能器头部尺寸两倍的区域。第一次治疗后，在肌肉温度恢复到初始治疗前温度±0.3摄氏度并保持5分钟后，再进行其余两个速度条件的治疗。因变量是在测量皮褶厚度一半以下3厘米处测量的左小腿三头肌肌肉温度。
三种速度下的温度升高在0.4摄氏度以内（F2,20 = 0.07，P = 0.93）。治疗后的值（平均±标准差）范围从最慢速度时的42.7摄氏度±2.3摄氏度到最快速度时的43.1摄氏度±1.4摄氏度。时间对温度升高有显著影响（F1,10 = 155.68，P < 0.00001），从治疗前的37.8摄氏度±0.8摄氏度升高到治疗后的42.9摄氏度±1.9摄氏度。
在超声治疗（持续10分钟，1兆赫频率，100%连续占空比，1.5瓦/平方厘米强度，作用于换能器头部尺寸两倍的区域）中，换能器速度为2至3厘米/秒、4至5厘米/秒和7至8厘米/秒时，可观察到非常相似的肌肉温度升高。
