Gupta V N, Bhagat P K, Ott C E, Fried A M
Ultrasound Med Biol. 1982;8(3):249-61. doi: 10.1016/0301-5629(82)90031-x.
The attenuation coefficient, propagation velocity and backscattering coefficient were measured in vitro, on freshly excised and functionally impaired rabbit kidneys. subcutaneous glycerol treatment was used to introduce acute renal failure. Elevated plasma creatinine levels, measured prior to the excision of kidneys, were used as an index of the degree of renal functional impairment. Propagation velocity for the ten kidneys ranged between 1538-1575 m/s with that for the normals being 1540 +/- 4 m/s. Velocity was found to increase with increasing renal damage. The attenuation coefficient for all ten kidneys exhibited a linear frequency dependence over the range 3.5-6.5 MHz. The slope of the attenuation coefficient for the glycerol treated kidneys (0.723 dB/cm/MHz) was found to be higher than the slope for the normals (0.499 dB/cm/MHz). The frequency dependence of the backscattering coefficient was not altered by glycerol treatment leading to the postulate that modification of frequency dependent behavior of the attenuation coefficient in this experimental model is primarily due to absorption.
在体外对新鲜切除且功能受损的兔肾进行了衰减系数、传播速度和背向散射系数的测量。采用皮下甘油注射法诱导急性肾衰竭。在切除肾脏之前测量的血浆肌酐水平升高，用作肾功能损害程度的指标。十个肾脏的传播速度在1538 - 1575米/秒之间，正常肾脏的传播速度为1540±4米/秒。发现速度随肾损伤程度的增加而增加。所有十个肾脏的衰减系数在3.5 - 6.5兆赫范围内呈现线性频率依赖性。发现甘油处理过的肾脏的衰减系数斜率（0.723分贝/厘米/兆赫）高于正常肾脏的斜率（0.499分贝/厘米/兆赫）。甘油处理并未改变背向散射系数的频率依赖性，由此推测在该实验模型中衰减系数频率依赖性行为的改变主要是由于吸收。
