Development and implementation of a quality control protocol for B-mode ultrasound equipment.

Purpose: Quality assurance (QA) of ultrasound (US) equipment is currently required in only a few countries around the world. In Greece, no national or other norms exist for regulating the use of US equipment. However, to obtain accreditation for the radiology department of a Greek hospital, the establishment and implementation of a quality control (QC) protocol and a QA programme for US equipment was required.

Materials And Methods: A literature review regarding US QC/QA procedures was performed. The information collected was used as a guide to create a QC/QA protocol and to obtain an appropriate US QC phantom. Drafting and testing of the initial protocol lasted 6 months. Its final version was implemented for 18 months in two US systems and five US transducers.

Results: The QC tests included in the protocol evaluate mechanical and electrical safety, image display, uniformity, penetration depth, distance accuracy, greyscale display, anechoic object imaging, geometric distortion, and axial/lateral resolution. The only QC test that failed was the test for uniformity since intense non-uniformities were observed that led to the replacement of two linear transducers.

Conclusion: US imaging is considered safe and, where appropriate, is preferred over imaging modalities that use ionizing radiation. However, the lack of QC/QA implies that US image quality is not routinely monitored. Therefore, the possibility of malfunctions that may go undetected and lead to wrong diagnosis cannot be excluded. A QC/QΑ programme can contribute to the elimination of such errors and ensure that performance is maintained over time.