Study on Quantitative Echography of Ocular Lesions with A Newly Developed Ultrasonic Diagnostic Equipment

在眼眶病变的超声诊断中，评价目标组织的超声反射率是非常重要的。用于此目的的方法被称为定量超声检查。它可以分为两类：一类是根据表面反射率来判断点状或膜状病变的性质，另一类是根据内部反射率来估计占位性病变的组织学特征。在以往的眼部点状或膜状病变，以及眼眶内的点状病变是根据超声对靶组织的反射率来诊断的。我们用Kretztech ik 7200 MA研究了许多眼膜样病变，如视网膜脱离、玻璃体出血和增殖膜形成。从这些结果中，定量超声检查中的两个问题成为研究的主题。其中一个问题是，A型超声束通过Targ…的方向更多的ET组织不能在显示器上显示。现代超声诊断设备的问世解决了这一问题，可以在B超图像上显示A型超声波束的方向。将超声波束垂直于病变表面或中心，是一种简单而精确的方法。第二个问题是，为了确定角蛋白膜样病变的反射率，需要有标准组织的反射率，以与巩膜进行比较。正常情况下，至少应该进行两次反射率判断，一次来自目标组织，另一次来自标准组织。在新开发的设备中，A模式图像可以在屏幕上扩展和放大。各个峰的反射率可以用刻度来表示。因此，可以直接读取以分贝为单位的反射率的值。唯一要询问的是最初应该将增益设置在什么水平上。有几种方法可以确定收益的初始水平。首先，确定了我们用KretzTechnic 7200 MA获得的数据。其次，根据四幅不同增益水平的B超图像进行判断。第三，考虑正常眼巩膜反射率的结果。定量超声检查在眼部病变中最重要的是鉴别脱离的视网膜与其他病变。非常重要的是，在某些情况下，分离的视网膜对超声束没有表现出高反射率。以下是一些案例。1)发病后的时间间隔。随着时间的推移，会发生萎缩性变化。结果，脱离的视网膜失去了特有的高反射率。(2)脱离的视网膜延长。在一些小范围视网膜脱离的病例中，由于反射角度的原因，图形肿胀，超声反射率错误地被认为是低的。在很大程度上，萎缩的过程经常发生。(3)视网膜劈裂。它是与脱离的视网膜相鉴别的病变之一。还应考虑尺寸、体型或厚度等其他特征。(4)炎症。在继发性视网膜脱离中，反射率通常较低。(5)增殖过程。在糖尿病玻璃体视网膜病变等玻璃体增生性病变的情况下，超声反射率会受到很大影响。(6)不同位置反射率的差异。据说，在脱离的视网膜中，周边的反射率与后部的反射率相同或更高。(7)与巩膜前层比较。有时，巩膜前层的反射率有助于区分脱离的视网膜。(8)年龄。在此基础上，对各种视网膜脱离进行了研究，包括新鲜的和陈旧的，简单的和复杂的，特发性的和继发性的。部分成果或意见已在国际和国内会议上公布。较少

In ultrasonic diagnosis of ocular and orbital lesions it is important to evaluate the ultrasonic reflectivity of the target tissue. The method used for the purpose, is termed as quantitative echography. It can be divided into two categories: the one is to estimate the nature of point-like or membrane-like lesions from their surface reflectivity, and the other is to estimate the histologic characteristics of space-occupying lesions from their internal reflectivity. In the former point-like or membrane-like lesions in the eye, and point-like lesions in the orbit are diagnosed on the reflectivity of ultrasound to the target tissue. We have studied many cases of ocular membrane-like lesions such as retinal detachment, vitreous hemorrahge and proliferative membrane formation using Kretztechnik 7200 MA. From those results two problems in doing quantitative echography have become the subject of investigation. One of the problems is that the direction of A-mode ultrasonic beam through the targ … More et tissue could not be displayed on the monitor. The problem has been solved after the advent of the modern ultrasonic diagnostic equipment, in which the direction of A-mode ultrasonic beam can be displayed on the B-mode image. It is easily and precisely to apply the ultrasonic beam perpendicularly to the surface or to the center of the lesion. The second problem is that for determining the reflectivity of a ceratin membrane-like lesion, it is necessary to have the reflectivity from the standard tissue, the sclera to compare with. Ordinarily reflectivity judgment should have been done twice at least, the one from the target tissue and the other from the standard tissue. In the newly developed equipment A-mode image can be extended and enlarged on the screen. Reflectivity of the individual peaks can be shown with the scale. Therefore the value of reflectivity with the unit of dB can be directly read. The only point to be inquired is on what level the gain should be initially set. There are several ways to decide the initial level of the gain. First, it is decided on the data of ours obtained with Kretztechnic 7200 MA. Second, it is judged from four B-mode images of different level of gain. Third, the results of reflectivity of the sclera in the normal eyes would be considered. Further investigation is necessary to decide the best way.The most important thing in quantitative echography in the ocular lesion is to differentiate the detached retina from other lesions. It is extremely important that in some case the detached retina fail to show high reflectivity to the ultrasonic beam. The followings are the cases. 1) The time interval after the onset. As the time passes, atrophic changes develop. As the result, the characteristic high reflectivity of the detached retina become absent. (2) Extension of the detached retina. In some cases of the detached retina of small extent, the figure is bullous, and the ultrasonic reflectivity is erroneously as low, because of the angle of reflection. In the cases of large extent the atrophic processes frequently develop. (3) Retinoschisis. It is one of the lesions to be differentiated from the detached retina. Other characteristics such as size, figure or thickness should be considered. (4) Inflammation. In secondary retinal detachment the reflectivity is often low. (5) Proliferative processes. In cases of proliferative processes in the vitreous such as diabetic vitreoretinopathy the ultrasonic reflectivity is much effected. (6) Difference of the reflectivity in the different localization. It is said that in detached retina the reflectivity in the periphery is the same or higher, compared with that in the posterior. (7) Comparison to the prescleral layer. Sometimes reflectivity of the prescleral layer is useful to differentiate the detached retina. (8) Age. Age is said to be considered to evaluate the reflectivity.Upon those points mentioned above, investigation in many kinds of retinal detachment, fresh and old, simple or complicated, idiopathic or secondary, are going on. A part of the results or opinions have been presented in international and domestic meetings. Less