Spectral Doppler refers to the combination of either continuous wave Doppler or pulsed Doppler with a spectral display. Spectral Doppler provides a quantitative analysis of the velocity and direction of blood flow.
The Fourier spectrum analyzer performs a fast Fourier transformation on the Doppler signal. The amplitudes of the resulting spectra are encoded as brightness. In the 2D spectral display, the frequency shift is depicted in the vertical and the time in the horizontal axis. The range of blood velocities in the volume produces a corresponding range of frequency shifts.

See also Acceleration Index and Triplex Exam.

Ultrasound machines, with their various components and types, have revolutionized the field of medical imaging. These devices enable healthcare professionals to visualize internal structures, assess conditions, and guide interventions with real-time imaging capabilities. Today, medical ultrasound systems are complex signal processing machines. Assessing the performance of an ultrasound system requires understanding the relationships between the characteristics of the system, such as the point spread function, temporal resolution, and the quality of images. Image quality aspects include the detail resolution, contrast resolution and penetration. Systems with microbubble scanner modification are particularly suitable for contrast enhanced ultrasound.


In summary, ultrasound machines have diverse performance levels and corresponding price ranges, catering to various medical imaging needs. From low-performance systems with basic imaging capabilities to high-performance and premium systems with advanced features, ultrasound technology continues to advance healthcare imaging capabilities.
See also Ultrasound Physics, Handheld Ultrasound, Environmental Protection, Equipment Preparation.

From Siemens Medical Systems;
'Conventional ultrasound systems are unable to compensate for the unique acoustic signature of individual patients. But there is nothing conventional about the new ACUSON Sequoia™ C512 echocardiography system with Sequoia™ matched response technology.'

From ALOKA Co., Ltd.;
'A Platform for Digital, Pure-Beam Imaging The high-performance, ALOKA ProSound SSD-3500 utilizes advanced ProSound technologies including:
Fully digital beam former A wide dynamic range, 12-bit A/D converter Multi beam processing.
The SSD-3500 also helps you achieve more efficient examinations. Its ergonomic, user-friendly design enables you to customize the system according to your specific application needs.'

From ALOKA Co., Ltd.;
'The ProSound SSD-4000 utilizes the most advanced acoustic technologies available today, and its multidisciplinary technology architecture enables it to offer great versatility and flexibility over a wide range of clinical applications.
With its new-generation, front-end technology including a 12-bit A/D converter, the ProSound SSD-4000 offers superior contrast resolution−especially when compared to 10-bit systems.'