Quality assurance testing of transoesophageal echocardiography probes

Investigation of the Impact of Defective Ultrasound Transducers on Clinical Image Quality in Grayscale 2-D Still Images

OBJECTIVE

There are several studies that show high defect rates of transducers in clinical use. The purpose of the present study was to investigate whether image quality and the risk for misdiagnosis is affected by using defective transducers.

METHODS

Four defective transducers with varying degrees of defect severity, still in clinical use, were selected. Forty artifact-affected clinical images from each transducer were compared with images acquired from fully functional transducers, of the same model, in an observer study where four experienced radiologists rated each of the 320 images. The rating tasks included if the artifacts were detectable, if the possible artifacts might affect the diagnosis, how well structural details were reproduced and, finally, an assessment of overall image quality.

RESULTS

The artifacts in the images were detectable for three of the four transducers (p < 0.05), and in 121 of 640 assessments of the images from the defective transducers the observers were confident that the artifacts could affect the diagnosis. All four faulty transducers were assessed to have decreased ability to resolve structural details (p < 0.05), and three of the four transducers were assessed to have worse overall image quality (p < 0.05).

CONCLUSION

The present study shows that image quality and the risk of misdiagnosis can be affected by using defective transducers. This highlights the importance of frequent quality control of the transducers to avoid decreased image quality and even misdiagnosis.

A Sticky Situation: The Unfortunate Consequence of Chewing Gum

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Foreign substances can interfere with the TEE probe, causing poor image quality.

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Operators should be aware of the reasons for diffusely anechoic TEE images.

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Poor identification of echocardiographic artifacts may lead to adverse outcomes.

Structural and Electrical Integrity of Transesophageal Echocardiography Probes: Importance and Key Concepts

The clinical utility of transesophageal echocardiography (TEE) is well-established for patients undergoing cardiac surgery. With the increase in percutaneous structural heart disease procedures that rely on TEE for procedural guidance, the use of TEE probes is expanding. Although there are well-established protocols for routine cleaning and decontaminating TEE probes between patient use, there is a lack of awareness and misconceptions about maintaining TEE probes' structural and electrical integrity. The electrical leakage test (ELT) is routinely performed between patient use. From a patient safety standpoint, the ELT is necessary to ensure the longevity of this expensive equipment and prevent disruptions to the workflow in a busy department caused by TEE probes being decommissioned due to probe damage. This technical communication aims to highlight the importance of maintaining TEE probes' structural and electrical integrity. The article also highlights and discusses probe handling techniques between patient use, emphasizing the ELT to ensure patient safety and compliance with national and international standards.

Image Analysis for Ultrasound Quality Assurance

The quality assurance (QA) of ultrasound transducers is often identified as an area requiring continuous development in terms of the tools available to users. Periodic evaluation of the transducers as part of the QA protocol is important, since the quality of the diagnostics. Some of the key criteria determining the process of developing a QA protocol include the complexity of setup, the time required, accuracy, and potential automation to achieve scale. For the current study, a total of eight different ultrasound machines (12 transducers) with linear transducers were obtained separately. The results from these 12 transducers were used to validate the protocol. WAD-QC was used as part of this study to assess in-air reverberation patterns obtained from ultrasound transducers. Initially, three in-air reverberation images obtained from normal transducers and three obtained from defective transducers were used to calculate the uniformity parameters. The results were applied to 12 other images obtained from independent sources. Image processing results with WAD-QC were verified with imageJ. A comparison of raw data for uniformity showed consistency, and using controls based on mean absolute deviation yielded identical results. WAD-QC can be considered as a powerful mechanism for quick, efficient, and accurate analysis of in-air reverberation patterns obtained from ultrasound transducers.

Making a Molehill out of a Mountain: A Case of Transesophageal Echocardiographic Probe Malfunction

• Probe malfunction during TEE is an underrecognized problem. • MR severity assessment: host (e.g., BP), technical (e.g., gain), probe malfunction. • Clues for malfunction 1: disparity between TTE and TEE; CW and color Doppler. • Clues for malfunction 2: unexplained poor image quality; need for high gain. • Transducer temperature can affect image quality.