Quality control of ultrasound transducers: analysis of evaluation parameters and results of a survey of 116 transducers in a single hospital.

Abstract

The aim of this study was to develop a quality control programme for ultrasound equipment and assess equipment performance at a single hospital.
We tested 116 transducers by means of a phantom; ultrasound quality control tests were done on parameters from B-mode images, and each parameter was rated according to a three-point score as good, sufficient or poor.
Surface transducers showed worse performance in terms of image uniformity, with 7/55 (13%) transducers rated poor, and depth of penetration, with 24/55 (44%) transducers, rated sufficient or poor. The 3.5-MHz transducers showed worse performance in lateral resolution, with 18/48 (38%) rated poor, and particularly in focusing, with 40/48 (83%) classified as poor. In addition, the 3.5-MHz transducers proved less accurate in vertical distance accuracy than in horizontal distance, with 31/48 (64%) considered sufficient. No significant geometric distortions of masses were identified, although 4/116 (3%) transducers failed to visualise two masses.
The first goal of an ultrasound quality control programme is to establish specific parameters to evaluate equipment performance and, should results be below recommended action levels, implement corrective measures.