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Virtual Journal for Biomedical Optics

Virtual Journal for Biomedical Optics


  • Editor: Gregory W. Faris
  • Vol. 2, Iss. 10 — Oct. 31, 2007

Estimating weak ratiometric signals in imaging data. I. Dual-channel data

Josef Broder, Anirban Majumder, Erika Porter, Ganesh Srinivasamoorthy, Charles Keith, James Lauderdale, and Andrew Sornborger  »View Author Affiliations

JOSA A, Vol. 24, Issue 9, pp. 2921-2931 (2007)

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Ratiometric fluorescent indicators are becoming increasingly prevalent in many areas of biology. They are used for making quantitative measurements of intracellular free calcium both in vitro and in vivo, as well as measuring membrane potentials, pH, and other important physiological variables of interest to researchers in many subfields. Often, functional changes in the fluorescent yield of ratiometric indicators are small, and the signal-to-noise ratio (SNR) is of order unity or less. In particular, variability in the denominator of the ratio can lead to very poor ratio estimates. We present a statistical optimization method for objectively detecting and estimating ratiometric signals in dual-wavelength measurements of fluorescent, ratiometric indicators that improves on standard methods. With the use of an appropriate statistical model for ratiometric signals and by taking the pixel–pixel covariance of an imaging dataset into account, we are able to extract user-independent spatiotemporal information that retains high resolution in both space and time.

© 2007 Optical Society of America

OCIS Codes
(100.3010) Image processing : Image reconstruction techniques
(100.5010) Image processing : Pattern recognition
(170.3880) Medical optics and biotechnology : Medical and biological imaging
(170.6280) Medical optics and biotechnology : Spectroscopy, fluorescence and luminescence

ToC Category:
Medical Optics and Biotechnology

Original Manuscript: November 7, 2006
Revised Manuscript: May 4, 2007
Manuscript Accepted: May 10, 2007
Published: August 23, 2007

Virtual Issues
Vol. 2, Iss. 10 Virtual Journal for Biomedical Optics

Josef Broder, Anirban Majumder, Erika Porter, Ganesh Srinivasamoorthy, Charles Keith, James Lauderdale, and Andrew Sornborger, "Estimating weak ratiometric signals in imaging data. I. Dual-channel data," J. Opt. Soc. Am. A 24, 2921-2931 (2007)

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