The experimental study for sonographic diagnosis and treatment of metastatic lymph nodes using 3D image reconstruction of intranodal vascularity

作为一种诊断转移性淋巴结的方法，超声检查已成为一种选择的方式。近年来有文献报道，结合B型超声内部回声和彩色多普勒超声的血管分布，可提高诊断的准确性。然而，在二维图像上，有时很难区分正常淋巴结的肺门模式和转移性淋巴结的异常模式。因此，为了更准确的诊断，我们进行了这项研究，以建立系统，能够显示结内血管的三维图像。首先，我们制作了大鼠下颌下腺的图像，因为它们的大小与人类颈部淋巴结差不多。然后我们扫描了一名志愿者的慢性淋巴结炎。超声诊断系统采用美国Acuson公司的Sequoia 512型超声诊断仪，探头置于载物台上，以0.5mm的间距沿一个方向移动。我们在每个位置制作了3秒钟的电影图像，其中包括大约70张静态图像。这些数据被传输到带有MO光盘的个人计算机上。三维图像重建采用Perl API，体绘制采用VolVis。与原始超声图像一样，血管和其他软组织分别以暖色和灰度表示。血管密度设为0.8，其他软组织密度视其体积而定，以突出血管分布。改进固定装置，以便适用于每个位置; 2.缩短重建时间，3。更准确的亮度和不透明度设置，4.大鼠下颌下腺和人体淋巴结的轮廓提取;无噪声提取真实的血管。

As a diagnostic method for metastatic lymph nodes, sonography has become a modality of choice. It has been reported these days that the diagnostic accuracy could be improved when not only the internal echoes by B-mode sonography but also the vascularity by color Doppler sonography were evaluated. However, it is sometimes difficult to differ the hilar pattern in normal nodes from the aberrant pattern in metastatic lymph nodes on two-dimensional images. Therefore, in order to make more exact diagnosis, we performed this study to establish the system which enabled to show the intranodal vascularity as three-dimensional images.At first we made images of rat submandibular glands, as they are about the same size as human cervical lymph nodes. Then we scanned human chronic lymphadenitis of a volunteer. As a sonographic diagnostic system we used Sequoia 512 (Acuson, co; USA)The sonograophic probe was set on the stage, it was moved in one direction with 0.5mm intervals. We made cine images for 3 seconds at each position, which included about 70 static images. These data were transferred to a personal computer with a MO disc. The three-dimensional image reconstruction was performed with the Perl API, and the volume rendering was performed with VolVis. The vascularity and the other soft tissue were expressed in warm colors and in gray-scale, respectively, like original sonographic images. The opacity of vascularity was set at 0.8, and that of the other soft tissue was set depending on their volume, in order to emphasize the vascularity.The problems to be solved are; 1. Improvement of the fixation apparatus in order to be applied to every position, 2. Reduction of reconstruction time, 3. More accurate setting of brightness and opacity, 4. Extraction of outline of rat submandibular glands and human lymph nodes, and 5. Extraction of the real vascularity without noises.