Meola Mario, Petrucci Ilaria
Dipartimento di Medicina Interna, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
G Ital Nefrol. 2012 Jan-Feb;29(1):81-91.
Sonography is an imaging technique that generates tomographic images using ultrasound. The sound constitutes mechanical energy transmitted in a medium by pressure waves. Sound waves with frequencies greater than 20 kHz are called ultrasounds. Diagnostic ultrasounds use frequencies from 1 to 20 MHz. Ultrasound equipment is composed of a scanner, an image monitor, and different transducers that transform acoustic energy into electrical signals and electrical energy into acoustic energy (piezoelectric effect). The spatial resolution defines the minimum distance between two reflectors or echogenic regions that can be imaged as separate reflectors. The spatial resolution is mainly determined by the array design (linear, curved and sectorial) and by the operative system of the transducer. Modern ultrasound machines are very sophisticated medical devices that often support many transducers, imaging modes and display devices. The scan converter memory is the device in which images are formed and then presented to the monitor and to the hard copy devices.
超声检查是一种利用超声波生成断层图像的成像技术。声音是通过压力波在介质中传播的机械能。频率大于20千赫的声波称为超声波。诊断超声使用1至20兆赫的频率。超声设备由扫描仪、图像监视器和不同的换能器组成，这些换能器将声能转换为电信号，将电能转换为声能（压电效应）。空间分辨率定义了两个反射器或回声区域之间的最小距离，这两个反射器或回声区域可被成像为单独的反射器。空间分辨率主要由阵列设计（线性、弯曲和扇形）以及换能器的操作系统决定。现代超声机器是非常精密的医疗设备，通常支持多种换能器、成像模式和显示设备。扫描转换器存储器是形成图像然后呈现给监视器和硬拷贝设备的装置。
