Influence of ultrasound image acquisition setup and region of interest size on the grey-scale echo intensity values of ultrasound images using a muscle phantom
The influence of ultrasound equipment setup and region of interest (ROI) size on the grey-scale brightness values of ultrasound images was investigated using a muscle phantom. The effects of focus, gain, depth, zoom and ROI size were verified. The Echo Intensity (EI) was estimated using ImageJ software. No significant differences were found in average brightness when changes were made to focus and zoom. EI rose linearly with an increase in gain and decreased linearly with increasing depth of penetration selected on the equipment. EI decreased logarithmically with the increase in size of the ROI. We propose dividing EI values by respective gains as an option to limit the influence of gain changes on EI. Other alternatives must still be investigated regarding the influence of depth on EI. This work is intended to help researchers make decisions based on parameters that may be influenced by their EI measurements, such that valid interpretations can be made.