Image Browsing in Slow Medical Liquid Crystal Displays1

Rationale and Objectives

Statistics show that radiologists are reading more studies than ever before, creating the challenge of interpreting an increasing number of images without compromising diagnostic performance. Stack-mode image display has the potential to allow radiologists to browse large three-dimensional (3D) datasets at refresh rates as high as 30 images/second. In this framework, the slow temporal response of liquid crystal displays (LCDs) can compromise the image quality when the images are browsed in a fast sequence.

Materials and Methods

In this article, we report on the effect of the LCD response time at different image browsing speeds based on the performance of a contrast-sensitive channelized-hoteling observer. A stack of simulated 3D clustered lumpy background images with a designer nodule to be detected is used. The effect of different browsing speeds is calculated with LCD temporal response measurements from our previous work. The image set is then analyzed by the model observer, which has been shown to predict human detection performance in Gaussian and non-Gaussian lumpy backgrounds. This methodology allows us to quantify the effect of slow temporal response of medical liquid crystal displays on the performance of the anthropomorphic observers.

Results

We find that the slow temporal response of the display device greatly affects lesion contrast and observer performance. A detectability decrease of more than 40% could be caused by the slow response of the display.

Conclusions

After validation with human observers, this methodology can be applied to more realistic background data with the goal of providing recommendations for the browsing speed of large volumetric image datasets (from computed tomography, magnetic resonance, or tomosynthesis) when read in stack-mode.

Key Words: Model observer, display quality, contrast sensitivity, temporal response