Contrast microbubbles can be destroyed by intense ultrasound and the scattered signal level can increase abruptly for a short time during microbubble destruction, resulting in an acoustical flash (sudden increase in echogenicity).
Intermittent imaging with high acoustic output utilizes the properties of contrast microbubbles to improve blood-to-tissue image contrast by imaging intermittently at very low frame rates.
The frame rate is usually reduced to about one frame per second, or it is synchronized with cardiac cycles so that enough contrast microbubbles can flow into the imaging site where most microbubbles have been destroyed by the previous acoustic pulse. Because bubbles are destroyed by ultrasound, controlling the delay time between frames produces images whose contrast emphasizes regions with rapid blood flow rate or regions with high or low blood volume.

From GE Healthcare.;
'The System of Choice for Shared Service.
The LOGIQ® 7 system provides a full range of clinical applications including abdominal, small parts, surgery, vascular and cardiac imaging and the power of GE's patented TruScan architecture. Just imagine an ultrasound system so versatile and reliable that it can meet the demands of virtually any clinical setting. And an ergonomic design that improves scanning comfort and clinical work flow.'

From GE Healthcare.;
'The System of Choice for General Imaging
Imagine a leading-edge ultrasound system so versatile that it can meet the demands of virtually any clinical setting. With the LOGIQ® 9, you'll have a high-performance system capable of multi-dimensional imaging for a full range of clinical applications - from abdominal to breast to vascular imaging. And an ergonomic design that improves scanning comfort and clinical work flow. Now, imagine what LOGIQ® 9 could do for you and your patients.'

Poiseulles law states that the flow rate in a long, straight tube with laminar flow is proportional to its length and viscosity and inversely proportional to the fourth power of its radius.

See also Proportionality Constant.

Ultrasound technology has evolved significantly, providing sonographers with a wide range of ultrasound machines. As technology has advanced, portable ultrasound equipment, including handheld ultrasound systems, have emerged in the field of medical imaging. However, these devices may have limited imaging capabilities and reduced image quality compared to larger systems.
Types of ultrasound systems compiled according to their portability:

In summary, pros and cons of portable ultrasound machines:

See also Ultrasound Accessories and Supplies, Environmental Protection, Sonographer, Ultrasound Technology and Equipment Preparation.