Image Display SystemsImage Display SystemsOptimizing the Optimizing the EnvironmentEnvironment

Stephen G DaviesStephen G Davies

Consultant RadiologistConsultant Radiologist

Royal Glamorgan HospitalRoyal Glamorgan Hospital

PACS Image viewingPACS Image viewing

Radiologist reporting roomRadiologist reporting room Radiographer quality control stationRadiographer quality control station Clinic viewing in wards and clinicsClinic viewing in wards and clinics

Radiologist reportingRadiologist reporting

Heat Heat DeskingDesking SeatingSeating NoiseNoise LightLight

Perception factorsPerception factors

Spatial and contrast resolution of the Spatial and contrast resolution of the display devicedisplay device

Brightness and luminance of the Brightness and luminance of the monitormonitor

Extraneous light in the reading roomExtraneous light in the reading room Displayed field size; magnification and Displayed field size; magnification and

zoomzoom Signal to noise of the displayed imageSignal to noise of the displayed image

Extraneous lightExtraneous light

Significant effect on performance of viewersSignificant effect on performance of viewers Decreases the perceived object contrast – Decreases the perceived object contrast –

reducing the detection of the objectreducing the detection of the object More significant in a PACS environmentMore significant in a PACS environment

Low luminance levels of monitors compared with Low luminance levels of monitors compared with viewboxes (6:1)viewboxes (6:1)

Increasing luminance increases contrast Increasing luminance increases contrast sensitivity sensitivity

Effect more marked in the low luminance rangeEffect more marked in the low luminance range

Radiologist reportingRadiologist reporting

Lighting conditionsLighting conditions No standardsNo standards General principlesGeneral principles

ControlControl Ambient light levelsAmbient light levels Consider all tasks e.g. readingConsider all tasks e.g. reading Reflected lightReflected light

Radiographer quality controlRadiographer quality control

Lighting conditionsLighting conditions Just as important as for radiologist Just as important as for radiologist

reporting quality control of imagesreporting quality control of images Also need to read clinical request for Also need to read clinical request for

verificationverification

Radiographer viewingRadiographer viewing

Heat outputHeat output Room layoutRoom layout

Clinical viewingClinical viewing Significant challengeSignificant challenge Lighting a key issueLighting a key issue

Bright for clinical examinationBright for clinical examination Dim for image viewingDim for image viewing

Clinical ViewingClinical Viewing

Desk space is at a premiumDesk space is at a premium Theatres a special caseTheatres a special case Flat screen monitorsFlat screen monitors

Summary Summary

Ambient lighting conditions pose the Ambient lighting conditions pose the greatest challenge to display greatest challenge to display systems at presentsystems at present

Heat and desk space are becoming Heat and desk space are becoming less importantless important