Uppsala University Hospital: Ultrasound System Clinical Trial Results
CARESTREAM Touch Prime Ultrasound System delivers high resolution image at good frame rate with minimal artefacts.
Note from the editor: “artefacts” is the preferred spelling in Sweden
Ultrasound developments over the last decade have made leaps and bounds in improving the accuracy of diagnoses, particularly in difficult-to-scan conditions. The creation of countless modalities on the backbone of the B-mode image has created a culture where clinicians expect top-quality images, even in suboptimal imaging scenarios.
However, given the complex and intersecting properties of ultrasound, any change must be synchronized with other parameters. For example, the high-quality images achieved today are dependent upon a high density of scan lines that capture an increasing volume of data. Duplex modes, such as color flow (Doppler imaging), increase the quantity of information captured. So it follows that the frame rate – the temporal resolution – must be accelerated to keep pace with the data being captured.
Additionally, the increased speed and the amount of data captured have the potential to create artefacts. These might be difficult to notice but will impair image resolution nonetheless. This occurrence tasks the ultrasonographer to constantly apply knowledge to avoid misdiagnosis of artefacts as pathologies (false positives), and to uncover pathologies that could be hidden by artefacts (false negatives).
Ultrasound system clinical trial
The challenge, therefore, for ultrasound manufacturers is to build a machine that gives a high resolution image at a good frame rate, and can maintain this performance when the patient is difficult to scan and/or we add other modalities like Doppler.
Based on our clinical trial, we believe Carestream Health has met the challenge with its CARESTREAM Touch Prime ultrasound system. In the spring of 2016, we put the system through the paces of a clinical trial for four months, performing about 800 exams during that time.
SynTek architecture is departure from serial line-by-line acquisition
A narrow beam is one of the important factors of B‑mode image quality as many artefacts have their origin in beam thickness (1). This is why many systems have focal zones even though they can produce a narrow beam at one depth only.
The SynTek beamforming architecture in the CARESTREAM Touch Prime is a departure from scanline-by-scanline image acquisition. Instead, SynTek insonates the tissue under examination in multiple directions, using near synchronous, independent ultrasound pulses. It then compensates for the differences in the round trip travel times of the returning echoes before combining the data into a coherent image.
When these multiple transmit events are combined, the result is an ultrasound beam that is uniformly narrow from nearfield to the deeper portions of the image whilst retaining a very high frame rate. The system is not dependent on one scan line being formed before the next acquisition starts. Also, this performance is independent of the use of Doppler, and provides the image quality shown in the example at a high frame rate.
Simplified control for sonographer
Images are enhanced further with Smart System Control (SSC), a real-time optimisation technique. In color, Doppler, and B-modes, the SSC algorithm takes a user’s preference for frame rate or resolution, and continuously optimizes it over 25 other system parameters (including some that are not under user control).
For example, for B-mode this includes the number of focal zones, transmit beams, and compounding angles, as well as the line density. The Smart System Control optimizes the parameters in the background, in real time, and automatically. It provides the necessary adjustments to ensure optimized images without requiring keyboard controls that distract the sonographer.
We found that Smart System Control along with the SynTek architecture helped lighten the load on our ultrasonographers. Instead of addressing factors that can hinder the image resolution, they can concentrate on creating quality images that result in fast and more accurate diagnosis.
Clinical trial conclusion
Smart System Control and the SynTek architecture enable the CARESTREAM Touch Prime Ultrasound System to produce a B-mode image with:
- Good uniform spatial resolution throughout the image
- An improved contrast resolution as artefacts resulting from beam thickness are reduced, and
- A very high frame rate not compromised by the addition of Doppler or other modalities.
Learn more about SynTek architecture. #ultrasound
Dr. Anders Nilsson, MD, PhD, is Head of Ultrasound in the Department of Surgical Sciences, Radiology, at Uppsala University Hospital in Sweden. It is Sweden’s oldest university hospital, with a distinguished history in developing innovative solutions that make the best use of new technology, new scientific findings, and new ways of working.
Reference: Nilsson A., Artefacts in sonography and Doppler. European Radiology, Volume 11, Issue 8, 2001