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Light source-induced error in computer-assisted image analysis with a video-based system.

F A Stutz·A F Hefti·C H Gibbs
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Abstract

OBJECTIVE: We tested the hypothesis that two different light sources, an alternating current fluorescent viewbox and a direct current halogen viewbox, do not differ with respect to their ability to illuminate reproducibly a radiograph during image capture. STUDY DESIGN: Two radiographs were taken: one with four hydroxyapatite chips mounted against a dry mandible and one without the chips. They were digitally subtracted with a video-based imaging system. The procedure was repeated at different times. RESULTS: A statistically significant difference among optical density measurements was found when the alternating current fluorescent viewbox (p < 0.001) was used and was related to light intensity variation. Such effect was not observed with the direct current halogen viewbox (p = 0.873). CONCLUSION: Study design efficiency was increased by 212% with the use of the direct current halogen viewbox so that to detect a specified treatment effect with a given level of statistical confidence, the sample size has to be 2.12 times greater if the alternating current fluorescent viewbox is used.

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Absorptiometry, PhotonAnalysis of VarianceArtifactsDiagnostic ErrorsHumansLightLightingMandibleRadiographic Image EnhancementRadiography, DentalReproducibility of ResultsSubtraction TechniqueVideo RecordingComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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F A Stutz, A F Hefti, C H Gibbs. 1996. Light source-induced error in computer-assisted image analysis with a video-based system.. https://doi.org/10.1016/s1079-2104(96)80030-8

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PubMed2000

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