Evaluation of a new test pattern for daily quality assurance of medical display monitors

Abstract

Introduction In the visual evaluation of daily quality assurance (QA) of medical display monitors, some well-established test patterns are available; however, the same pattern is always used. Therefore, it is difficult to detect luminance deterioration. Purpose We developed the new software for the daily QA of monitors (mdQA), in which randomized object (RO) patterns were generated. The RO patterns had a low-contrast object consisting of a randomly located sphere. In the present study, we evaluated whether these RO patterns can detect luminance deterioration. Materials and methods The mdQA was developed using Microsoft Visual Basic 2010 Express. The digital driving level (DDL) and the standard deviation (SD) of the RO pattern background, as well as the size and contrast of the object, were adjustable. In this study, the DDL and SD were set at 130 and 20, respectively. The object diameter was determined at 30 pixels. Contrast values varied from 4 to 8 pixels. We produced 40 patterns with and without the object using the mdQA. A receiver operating characteristic analysis was performed for the two different display luminance (400 and 320 cd/m 2 ) using a 2-megapixel color liquid crystal display (LCD) monitor. Ten radiation therapists observed the patterns and scored the confidence rate using a continuous scale. Results There was a statistically significant difference between the two LCD monitor conditions ( p Conclusion The developed mdQA enables the creation of RO patterns for the daily QA of medical display monitors; these RO patterns are useful in detecting luminance deterioration. Disclosure None.