Observer Performance Using Virtual Pathology Slides: Impact of LCD Color Reproduction Accuracy

Abstract

The use of color LCDs in medical imaging is growing as more clinical specialties use digital images as a resource in diagnosis and treatment decisions. Telemedicine applications such as telepathology, teledermatology, and teleophthalmology rely heavily on color images. However, standard methods for calibrating, characterizing, and profiling color displays do not exist, resulting in inconsistent presentation. To address this, we developed a calibration, characterization, and profiling protocol for color-critical medical imaging applications. Physical characterization of displays calibrated with and without the protocol revealed high color reproduction accuracy with the protocol. The present study assessed the impact of this protocol on observer performance. A set of 250 breast biopsy virtual slide regions of interest (half malignant, half benign) were shown to six pathologists, once using the calibration protocol and once using the same display in its "native" off-the-shelf uncalibrated state. Diagnostic accuracy and time to render a decision were measured. In terms of ROC performance, Az (area under the curve) calibrated = 0.8570 and Az uncalibrated = 0.8488. No statistically significant difference (p = 0.4112) was observed. In terms of interpretation speed, mean calibrated = 4.895 s; mean uncalibrated = 6.304 s which is statistically significant (p = 0.0460). Early results suggest a slight advantage diagnostically for a properly calibrated and color-managed display and a significant potential advantage in terms of improved workflow. Future work should be conducted using different types of color images that may be more dependent on accurate color rendering and a wider range of LCDs with varying characteristics.

Evaluation environment for digital and analog pathology: a platform for validation studies

“…8 However some groups, including the International Color Consortium, are filling the void and addressing the challenging issue of display and color calibration. [16][17][18] • Slide preparation.…”

Digital pathology in clinical use: where are we now and what is holding us back?

“…Two issues arise when considering the performance of displays: colour calibration and screen resolution. Krupinski et al . showed no change in diagnostic accuracy when pathologists viewed snapshots of breast cores on calibrated versus uncalibrated displays, but noted a faster time to diagnosis.…”

26.4: Display Color Error in the Medical Digital Image Workflow

“…Since the quality of the color information can have an impact on the eventual accuracy or speed of the diagnosis, it is important that the colors are rendered correctly. [2] Achieving and maintaining accurate color reproduction is already challenging for desktop monitors, and will be even more so as more users start viewing medical color images on mobile displays in uncontrolled lighting environments.…”