Development of real-time three-dimensional ultrasound system without reconstruction and its clinical application in cardiac surgery.

使用连续的2-D回波图像重建心脏的三维(3-D)与几个问题有关。从数据采集到三维显示的过程通常很耗时。这些问题限制了三维超声心动图在心血管外科领域的临床应用。本研究的目的是开发一种新的三维超声系统，实时地在空间上描绘心内结构的边界，并评估其在主要心脏瓣膜疾病中的临床可行性。本研究开发的实时三维超声系统可以通过对相控阵换能器(3.5 Mhz)的机械扫描获得体积数据，并在不存储图像数据和重建过程的情况下显示体绘制图像。该系统不仅可以进行实时数据采集，还可以进行三维显示。在第一个研究年(1998年)，包括左心室和二尖瓣在内的心内结构的3-D图像是清晰的…在20名患者中，有16名患者获得了更多和正确的信息(分)通过经胸入路使用新系统。在本系列的4例中，由于探头尺寸太大，超声波束的穿透受到胸壁的干扰，导致成像效果不佳。在第二个研究年中(1999)，利用数字并行处理将三维成像的帧速率提高到8f/s。该装置提高了经胸入路实时三维成像的图像质量。24分。其中10例为正常心脏，14例为二尖瓣病变。10例正常心脏均清晰显示左室腔及二尖瓣结构。在14例二尖瓣病变中，11例二尖瓣病变实时成像正确。在这一系列的3TS中，超声穿透不足导致三维成像不佳。总之，新研制的无重建过程的实时三维超声系统对二尖瓣、瓣膜和左室腔的空间解剖进行实时成像在临床上是可行的。随着技术的进一步改进，这种通过心外膜直接入路使用的新系统在提高心脏手术修复程序的准确性方面具有潜在的用途。较少

Three-dimensional (3-D) reconstruction of the heart using consecutive 2-D echo images is associated with several problems. The processing from data acquisition to 3-D display is generally time consuming. These problems limits clinical use of 3-D Echocardiography in cardiovascular surgical fields. The purpose of this research was to develop a new 3-D ultrasound system which delineates spatially the boundaries of intracardiac structure in real time and to evaluate its clinical feasibility in mainly valvular heart diseases. The newly developed real-time 3-D ultrasound system by the present research can acquire volumetric data from mechanical scanning of the phased array transducer (3.5MHz) and display the volume rendered images without storage of the image data and reconstruction process. This system allows not only real-time data acquisition but 3-D display. In the first research year (1998), 3-D images of the intracardiac structure intcluding left ventricle and mitral valve were clearly … More and correctly obtained in 16 of 20 patients (pts.) using the new system by transthoracic approach. In 4 pts.of this series, the penetration of ultrasound beam was disturbed by the chest wall resulting in suboptimal imaging caused by the large size of a probe. In the 2nd research year (1999), the frame rate of 3-D imaging was increased up to 8 f/sec using digital parallel processing. This device offered the improved image quality of real-time 3-D imaging by transthoracic approach. 24 pts. (10 ; normal heart, 14 ; mitral heart disease) were examined using the improved system by transthoracic approach. In all 10 normal hearts, the cavity of left ventricle and mitral valve structure was clearly visualized. In 11 of 14 pts.with mitral disease, pathologies of mitral valve were imaged correctly in real-time. In 3ts.of this series, penetration of ultrasound was insufficient causing poor 3-D imaging. In conclusion, the newly developed real-time 3-D ultrasound system without reconstruction process was shown to be clinically feasible for imaging of spatial anatomy of the mitral, valve and the cavity of the left ventricle in real time. With further technological improvement, this new system, used by direct epicardial approach, has the potential usefulness in increasing the accuracy of repairing procedures in cardiac surgery. Less