More About Ultrasound

Ultrasound technology is known by many names such as sonar, echography, sonography, Doppler, or ultra-sonography. Regardless of the terminology, the process is the same. It involves the creation of a fast (ultra) sound wave that is directed toward an object of interest and bounced back to a receiver. Once received, the signal can be analyzed to give information such as size, shape, distance, density, or speed. Depending on the application, the user can gain valuable information for each or any combination of these elements.

Marine mammals are the most prolific users of this technology and utilize it to locate friends, enemies, and food as well as for navigation. Human use was first introduced in the 19th century by naval forces to detect enemy subsurface vessels such as mines and submarines. Since that time, numerous medical applications have been developed that allow physicians to perform a myriad of diagnostic studies.

Probably the most widely used application of ultra-sonography is in prenatal care to visualize the status of fetal development. You may be more familiar with the most common urologic application for visualizing the prostate to detect hypo-echoic areas of the gland that may indicate growth of cancerous tissue.

As previously mentioned, diagnostic ultrasound involves bouncing a sound wave off of an object and analyzing the returning signal to ascertain certain information. The key element is a device (known as a transducer) that can both send a signal of known frequency and receive the returning signal and transmit that to the medium used for analysis, usually a computer.

Another important variable is the angle of incidence of the signal being sent as it is directed toward the desired object. Frequently, inconsistent angles are introduced during an examination that would account for a certain variation in results. With most ultrasound systems, the transducer or probe must be manipulated by the operator that allows for some measure of error with regards to the consistency of the angle of incidence.

The final component for correct ultrasound velocity measurements is the focal length and penetration depth of the ultrasound signal.

To obtain accurate readings, the angle of incidence of the ultrasound transducer must be known and constant throughout the measurement phase. The SureAngle™ probes and Gold Guard™ cradle of the Knoll/MIDUS System hold two ultrasonic transducers in the correct orientation on the penis while cavernosal artery blood velocity is measured.