Hoyt R H, Collins S M, Skorton D J, Ericksen E E, Conyers D
Circulation. 1985 Apr;71(4):740-4. doi: 10.1161/01.cir.71.4.740.
In animal hearts, the magnitude of integrated ultrasonic backscatter is increased in fibrotic myocardium. Our purpose in this study was to quantitate the relationship between ultrasonic backscatter and collagen deposition in 10 excised human hearts with old infarcts. A 2.25 MHz, 50% fractional bandwidth transducer was positioned at the transducer focal distance from the epicardium of each specimen. The radio frequency backscatter signal was digitized, squared, and integrated to yield the integrated ultrasonic backscatter, which was referenced to the backscatter from a water/steel interface. The interrogated myocardium was then excised and divided into two portions. One portion was assayed for hydroxyproline, a marker for collagen. A second portion was sectioned, stained with Masson's trichrome, and studied with the use of a computer-assisted image analysis system. There was a linear correlation between the magnitude of integrated backscatter and myocardial collagen content estimated by hydroxyproline assay (r = .78). Quantitative histologic analysis revealed a variable relationship between the transmural distribution of collagen and the corresponding transmural pattern of the backscatter signal. In two specimens exhibiting a discrete layer of subendocardial fibrosis, the backscatter amplitude was also increased in the subendocardial region. In specimens with other patterns of fibrosis, the local backscatter amplitude did not correspond to the transmural pattern of collagen distribution. We conclude that the quantitative analysis of ultrasonic backscatter shows promise for the noninvasive evaluation of myocardial fibrosis after infarction.
在动物心脏中，纤维化心肌的超声背向散射积分幅度会增加。本研究的目的是定量分析10个有陈旧性梗死的离体人心脏中超声背向散射与胶原沉积之间的关系。将一个2.25兆赫、分数带宽为50%的换能器置于距每个标本心外膜的换能器焦距处。对射频背向散射信号进行数字化、平方和积分，以产生超声背向散射积分，该积分以水/钢界面的背向散射为参考。然后切除被检测的心肌并分成两部分。一部分检测羟脯氨酸，它是胶原的标志物。另一部分切片，用马松三色染色法染色，并使用计算机辅助图像分析系统进行研究。超声背向散射积分幅度与通过羟脯氨酸测定法估算的心肌胶原含量之间存在线性相关性（r = 0.78）。定量组织学分析显示，胶原的透壁分布与背向散射信号的相应透壁模式之间存在可变关系。在两个显示心内膜下纤维化离散层的标本中，心内膜下区域的背向散射幅度也增加。在具有其他纤维化模式的标本中，局部背向散射幅度与胶原分布的透壁模式不对应。我们得出结论，超声背向散射的定量分析有望用于梗死心肌纤维化的无创评估。
