Ambient Lighting: Effect of Illumination on Soft-Copy Viewing of Radiographs of the Wrist

Brennan, Patrick C.; McEntee, Mark F.; Evanoff, Michael G.; Phillips, Peter; O’Connor, W.T.; Manning, David J.

doi:10.2214/ajr.05.2048

Cited by 110 publications

(62 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The study results, however, support and advance findings from previous studies that suggested an increase of ambient lighting will not degrade detection performance. Several studies using both simulated images and clinical radiographs have shown that moderate levels of ambient lighting (40-50 lx) should not degrade, and may improve, observer detection performance [5,8,9,25]. In contrast to the current study, however, the previous studies utilized observers who either had no radiology reading experience or were accustomed to reading images under elevated ambient lighting levels.…”

Section: Discussionmentioning

confidence: 72%

“…In contrast to film and CRTs, modern calibration-capable LCDs, with intrinsically low diffuse reflection coefficients and high luminance ratios may permit a moderate increase of ambient lighting without image quality degradation [7]. Following this assumption, theoretical, and psychophysical studies have provided preliminary evidence that radiologist performance should not degrade, and may improve, under a controlled ambient lighting increase [5,8,9].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Effects of Ambient Lighting in Chest Radiology Reading Rooms

et al. 2012

View full text Add to dashboard Cite

Under typical dark chest radiography reading room conditions, a radiologist's pupils contract and dilate as their visual focus intermittently shifts between the high luminance monitor and the darker background wall, resulting in increased visual fatigue and degradation of diagnostic performance. A controlled increase of ambient lighting may minimize these visual adjustments and potentially improve comfort and accuracy. This study was designed to determine the effect of a controlled increase of ambient lighting on chest radiologist nodule detection performance. Four chest radiologists read 100 radiographs (50 normal and 50 containing a subtle nodule) under low (E01 lx) and elevated (E050 lx) ambient lighting levels on a DICOM-calibrated, medicalgrade liquid crystal display. Radiologists were asked to identify nodule locations and rate their detection confidence. A receiver operating characteristic (ROC) analysis of radiologist results was performed and area under ROC curve (AUC) values calculated for each ambient lighting level. Additionally, radiologist selection times under both illuminance conditions were determined. Average AUC values did not significantly differ (p>0.05) between ambient lighting levels (estimated mean difference0−0.03; 95% CI, (−0.08, 0.03)). Average selection times decreased or remained constant with increased illuminance. The most considerable decreases occurred for false positive identification times (35.4±18.8 to 26.2±14.9 s) and true positive identification times (29.7± 18.3 to 24.5±15.5 s). No performance differences were statistically significant. Study findings suggest that a controlled increase of ambient lighting within darkly lit chest radiology reading rooms, to a level more suitable for performance of common radiological tasks, does not appear to have a statistically significant effect on nodule detection performance.

show abstract

Section: Discussionmentioning

confidence: 72%

Section: Introductionmentioning

confidence: 99%

The Effects of Ambient Lighting in Chest Radiology Reading Rooms

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Images were viewed on a dedicated image review station (DS3000, Agfa), which was calibrated for each reading session to DICOM Part 4 Curve standard. Ambient lighting conditions in the viewing room were maintained throughout the study at 25-40 lx [16].…”

Section: Discussionmentioning

confidence: 99%

Optimization of Computed Tomography Protocols: Limitations of a Methodology Employing a Phantom with Location-Known Opacities

et al. 2013

Self Cite

View full text Add to dashboard Cite

This study aimed to determine if phantom-based methodologies for optimization of hepatic lesion detection with computed tomography (CT) require randomization of lesion placement and inclusion of normal images. A phantom containing fixed opacities of varying size (diameters, 2.4, 4.8, and 9.5 mm) was scanned at various exposure and slice thickness settings. Two image sets were compared: All images in the first image set contained opacities with known location; the second image set contained images with opacities in random locations. Following Institutional Review Board approval, nine experienced observers scored opacity visualization using a 4-point confidence scale. Comparisons between image sets were performed using Spearman, Kappa, and Wilcoxon techniques. Observer scores demonstrated strong correlation between both approaches when all opacity sizes were combined (r=0.92, p<0.0001), for the 9.5 mm opacity (r=0.96, p<0.0001) and for the 2.4 mm opacity (r=0.64, p<0.05). There was no significant correlation for the 4.8 mm opacity. A significantly higher sensitivity score for the known compared with the unknown location was found for the 9.5 mm opacity and 4.8 mm opacity for a single slice thickness and exposure condition (p<0.05). Phantom-based optimization of CT hepatic examinations requires randomized lesion location when investigating challenging conditions; however, a standard phantom with fixed lesion location is suitable for the optimization of routine liver protocols. The development of more sophisticated phantoms or methods than those currently available is indicated for the optimization of CT protocols for diagnostic tasks involving the detection of subtle change.

show abstract

“…For other modalities, the FDA does not restrict the use of compression, but it does require manufacturers of devices that use irreversible compression to submit data on the impact of the compression on quantitative metrics of image quality (such as peak signalto-noise ratio) [3]. Since it is known that such simple metrics do not correlate well with human observer assessment of quality or performance for diagnostic tasks [5], the claim of the manufacturer that irreversible compression is satisfactory may not be sufficient and the burden remains on the responsible physician to assure that the image quality is sufficient to achieve a diagnostically acceptable goal.…”

Section: Compressionmentioning

confidence: 99%

“…2. Viewing conditions should be optimized to minimize eye fatigue by controlling reading room lighting to eliminate reflections on the monitor and lowering the ambient lighting level as much as is feasible without turning the lighting off completely (20-40 lx is recommended in the work space environment) [5]. Brighter ambient lighting may be tolerable or even desirable so long as conformance with AAPM Task Group 18 specifications is maintained.…”

Section: Displaymentioning

confidence: 99%