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The spatial resolution performance of a time-resolved optical imaging system using temporal extrapolation.

J C Hebden·D J Hall·D T Delpy
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Abstract

Optical imaging methods are being explored as a potential means of screening for breast cancer. Previous investigations of time-resolved imaging techniques have suggested that due to the lack of photons with sufficiently small pathlengths, the spatial resolution achievable through a human breast would be unlikely to be better than a centimeter. Experimental results presented here indicate, however, that higher resolution may be achieved by extrapolating the measured temporal distribution of transmitted photons. This is performed using a least-squares fit between data and an analytic model of photon transport. The spatial resolution of a time-resolved imaging system was evaluated by measuring the edge response produced by an opaque mask embedded in the center of a 51-mm-thick, very highly scattering medium. The limiting spatial resolution was improved from about 13 mm to about 5 mm.

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Breast NeoplasmsFemaleHumansLeast-Squares AnalysisMammographyMass ScreeningMathematicsModels, TheoreticalOnline SystemsTime FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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J C Hebden, D J Hall, D T Delpy. 1995. The spatial resolution performance of a time-resolved optical imaging system using temporal extrapolation.. https://doi.org/10.1118/1.597457

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