ECRI Update: Making Sound Decisions When Evaluating Ultrasound Technologies

By ECRI

Diagnostic ultrasound scanners transmit high frequency sound waves into a patient’s body and then process the returning echoes to generate images (or other data) that clinicians view on a video display. Common clinical applications include the use of ultrasound to assess the unborn fetus, to determine the size and contours of organs, to evaluate the heart for wall and valve abnormalities, and to guide interventional procedures, including needle biopsies, therapeutic injections, and surgical procedures.

Ultrasound scanners are available in a wide variety of sizes and configurations. “This variety, coupled with the wide range of potential applications, can make selection decisions a challenge,” explains Dan Merton, BS, RDMS, FAIUM, FSDMS, diagnostic ultrasound specialist and principal project officer in ECRI’s Device Safety group. Decision-makers need to understand the pros and cons of each configuration, they need to identify the features available on the models under consideration, and they need to assess the performance of those features.

Scanner Configurations
Conventional ultrasound scanners, as ECRI defines the term, are models that are permanently mounted on wheels. Also referred to as cart-based models, these scanners are available in several price points, from basic scanners costing less than $30,000 to premium models that can cost more than $250,000. Conventional scanners typically include a user interface, position-adjustable video display, and the ability to support a variety of transducers to meet different clinical needs. Conventional scanners are most commonly used by imaging specialists in dedicated imaging settings.

Portable ultrasound scanners, by contrast, are not permanently mounted on wheels and can be hand-carried between care settings. Portable scanners are available in a variety of formats including laptop, tablet, and handheld (wired or wireless) models. Portable scanners are primarily, but not exclusively, used for the use of ultrasound at the bedside by the treating clinician, as opposed to referring the patient to an imaging specialist when an ultrasound exam is indicated. POCUS allows clinicians to quickly determine whether an abnormality is present so they can expedite patient management decisions.

ECRI’s Testing
In the past decade, ECRI has tested and rated more than 40 scanner models, covering virtually all available configurations (as outlined below) and a wide range of clinical applications. Factors assessed during these evaluations include: scanner capabilities and design features relevant to the intended application; image resolution, as determined through ECRI’s standardized laboratory testing (see photos); features that impact workflow and user ergonomics; interoperability of the device within a network; cybersecurity concerns; and the ease of cleaning and disinfecting ultrasound systems and transducers.

Through this testing, ECRI has observed continued improvements in image quality and workflow features, along with the steady addition of advanced features designed to aid data acquisition and analysis. Merton explains: Scanners are expected to meet established requirements (based on the type of scanner evaluated), thus “it’s the availability and performance of advanced features that tends to differentiate one model from another.” Other differentiating factors include ease of use, which is affected by the accessibility and layout of controls, battery life, and portability of the device.

• Conventional Scanners: Conventional scanners typically offer multiple transducer ports, allowing several probes to be connected simultaneously, and numerous user-adjustable controls to optimize data acquisition. They also provide the greatest number of ergonomic features, such as height-adjustable control panels and large, high-resolution video displays to reduce eye strain. Some of the latest conventional scanners can be battery operated, which enhances workflow and allows more time-efficient exams. Additionally, premium models support the latest advancements in ultrasound imaging technology (e.g., elastography, 3-D/4-D imaging).
• Laptop-Style Portable Scanners: Laptop models can be placed on a tabletop for use but are most commonly used while mounted on a wheeled cart that has probe holders and storage bins for supplies. These scanners may provide similar capabilities as a conventional scanner, including advanced Doppler modes and transesophageal echocardiography (TEE), but in a smaller form factor that can be transported between facilities, or used where space is limited, such as in an operating room. Laptop scanners can range from approximately $25,000 to $100,000, depending on the configuration and transducers purchased. Merton notes that there has been a gradual shift away from interfaces that include lots of user-adjustable controls (which require advanced expertise) toward simpler, more automated designs that are better suited to POCUS users.
• Tablet-Style Portable Scanners: Tablet models consist of the scanner built into a dedicated video display that is used to view the acquired data and provide a touchscreen user interface. Tablet scanners can be placed on a table, attached to a wall mount, hand carried, or attached to a wheeled stand for transport within a facility. Tablet models typically support the most commonly used imaging and Doppler modes and a variety of transducers, but often do not have the advanced capabilities offered by premium laptop-style scanners. Prices range from approximately $20,000 to $75,000, depending on the configuration and transducers purchased.
• Handheld Scanners: Handheld scanners (also referred to as handheld probes) are a comparatively recent addition to the POCUS landscape. These models are compact enough to be held in one hand during use while the transducer is held in the other hand. Handheld probes are available in several application-specific configurations to allow assessments of either deep or superficial structures; endocavity probes are also available. Some models provide a dual-head transducer or have advanced technologies to expand their clinical applicability.

Typical uses of handheld probes include assessing trauma patients in emergency departments, imaging of the musculoskeletal system by orthopedic specialists, quick assessment of the heart in the ICU, and vascular access guidance. Both wired and wireless designs are available:

Wired models consist of a probe that is either hardwired to a small video display device or is connected via a USB cable to a personal electronic device (PED), such as a smartphone or iPad. In the latter configuration, the probe vendor’s software application is installed on the PED to provide the user interface and the ability to view the image.

Wireless models connect via Wi-Fi to a user-provided PED operating the probe vendor’s software application. Wireless scanners offer several advantages when used for interventional applications (e.g., no transducer cable to contaminate the surgical field, easier manipulation of the transducer due to the cable-free design).

While these low-cost ($2,000 to $10,000) devices typically cannot match the performance of premium cart-based ultrasound scanners, ECRI has found their image quality and other performance factors to be generally adequate for their intended POCUS applications.

To Learn More . . .
ECRI’s evaluations of ultrasound technologies can be accessed by members of ECRI’s Capital Guide, Device Safety, and associated programs. To learn more about membership, visit https://www.ecri.org/solutions/device-evaluations, or contact ECRI by telephone at (610) 825-6000, ext. 5891, or by e-mail at clientservices@ecri.org.