Ultrasound System and Transducer Specifications Used in Purchasing Decisions

Tender and Bid Specifications are often used to clarify and describe in detail the performance expectations of the medical devices prior to purchase. Frequently, such specifications include detailed hardware and software requirements for the ultrasound system and probes for screening, diagnosis, therapy or interventional guidance, or therapy. While some specifications are objective, reliable, and useful, for example, number of probe ports, inclusion of a gel warmer, display screen size, scanner weight and size, and operating modes, other technical specifications for an ultrasound system or probe in isolation are not necessarily indicative of the ultrasound diagnostic or therapeutic performance quality that the end-user will experience. Examples of tender specifications that may not directly correlate with imaging performance include the number of digital beam-former channels, frame rate, and dynamic range. Standard metrics that quantify the system-integrated transducer performance are clearly defined and thus more appropriate to use. For diagnostic ultrasound, these industry quality guidelines include but are not limited to spatial resolution and contrast resolution as a function of depth, uniformity, and depth of visualization. Unlike the more ambiguous tender specifications, these metrics are easy to demonstrate and measure across different ultrasound imaging systems and probes using standardized tissue-mimicking phantoms. 

In addition, several technical specifications used to set customer requirements for clinical performance are based on established technologies and historical data that do not consider the rapid advancement of technology in both hardware and software. Such advancements have allowed ultrasound to expand into new applications. Therefore, clinical users might miss opportunities to improve health care if Tender Specifications are not identified properly.

Lastly, technical specifications alone can never fully capture the clinical utility of an ultrasound system.  Ultimately, the ultrasound system must be used in a clinical setting where ease of use may be critically important to get an efficacious, relevant result in a timely manner.  Hence, feedback from the clinical end-users is vital when selecting the best ultrasound machine for a specific clinical need.

The American Institute of Ultrasound in Medicine recommends the following:

1. That tender and bid specifications be based on system-integrated transducer performance metrics that are relevant to the quality of ultrasound system performance, and metrics that are quantified using standardized methods accepted by the ultrasound community.
2. That purchase decisions include consultation with clinical end-users, and experts in ultrasound instrumentation, if available, to identify proper requirements related to clinical applications, ultrasound system performance quality, workflow, and automation.
3. That purchase decisions include consultation with specialists, as needed, to identify proper requirements for connectivity, data storage, data transfer, and data security.
4. That the seller provide access to a machine so clinical end-users and experts in ultrasound instrumentation, if available, can conduct hands-on evaluation of the clinical utility of the machine over a trial period prior to purchase.

This statement is endorsed by the: