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FLIMX: A Software Package to Determine and Analyze the Fluorescence Lifetime in Time-Resolved Fluorescence Data from the Human Eye.

Klemm M, Schweitzer D, Peters S, Sauer L, Hammer M, Haueisen J - PLoS ONE (2015)

Bottom Line: Specifically, we introduce a new adaptive binning approach as an optimal tradeoff between the spatial resolution and the number of photons required per pixel.An overview of the visualization capabilities and a comparison of static and adaptive binning is shown for a patient with macular hole.FLIMX's applicability to fluorescence lifetime imaging microscopy is shown in the ganglion cell layer of a porcine retina sample, obtained by a laser scanning microscope using two-photon excitation.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biomedical Engineering and Informatics, Technische Universität Ilmenau, POB 100565, 98694, Ilmenau, Germany.

ABSTRACT
Fluorescence lifetime imaging ophthalmoscopy (FLIO) is a new technique for measuring the in vivo autofluorescence intensity decays generated by endogenous fluorophores in the ocular fundus. Here, we present a software package called FLIM eXplorer (FLIMX) for analyzing FLIO data. Specifically, we introduce a new adaptive binning approach as an optimal tradeoff between the spatial resolution and the number of photons required per pixel. We also expand existing decay models (multi-exponential, stretched exponential, spectral global analysis, incomplete decay) to account for the layered structure of the eye and present a method to correct for the influence of the crystalline lens fluorescence on the retina fluorescence. Subsequently, the Holm-Bonferroni method is applied to FLIO measurements to allow for group comparisons between patients and controls on the basis of fluorescence lifetime parameters. The performance of the new approaches was evaluated in five experiments. Specifically, we evaluated static and adaptive binning in a diabetes mellitus patient, we compared the different decay models in a healthy volunteer and performed a group comparison between diabetes patients and controls. An overview of the visualization capabilities and a comparison of static and adaptive binning is shown for a patient with macular hole. FLIMX's applicability to fluorescence lifetime imaging microscopy is shown in the ganglion cell layer of a porcine retina sample, obtained by a laser scanning microscope using two-photon excitation.

No MeSH data available.


Related in: MedlinePlus

Comparison of the different fluorescent lifetime modelling approaches in a healthy volunteer.The fluorescence intensity as well as the fluorescence lifetimes τm (A) and τ1 (B) in spectral channel 1 are shown (154 x 154 pixels, 59 x59 μm2/pixel). The color scaling of the fluorescence lifetime plots is identical in each subfigure. The ETDRS grid is drawn on each subplot, and the mean values are given for each subfield of the grid. The fluorescence intensity image is the measured signal before binning.
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pone.0131640.g008: Comparison of the different fluorescent lifetime modelling approaches in a healthy volunteer.The fluorescence intensity as well as the fluorescence lifetimes τm (A) and τ1 (B) in spectral channel 1 are shown (154 x 154 pixels, 59 x59 μm2/pixel). The color scaling of the fluorescence lifetime plots is identical in each subfigure. The ETDRS grid is drawn on each subplot, and the mean values are given for each subfield of the grid. The fluorescence intensity image is the measured signal before binning.

Mentions: Fig 8A depicts the fluorescence intensity as well as the average fluorescence lifetime τm (Eq 13) and fluorescence lifetime τ1 (Fig 8B) in spectral channel 1 for the different fluorescence lifetime approximation models. In the case of the stretched exponentials, only two exponential functions were used, compared to the three exponential functions used in the other cases. Furthermore, the fluorescence lifetime of a stretched exponential is not directly comparable to the other approaches because it must be interpreted in conjunction with the corresponding β.


FLIMX: A Software Package to Determine and Analyze the Fluorescence Lifetime in Time-Resolved Fluorescence Data from the Human Eye.

Klemm M, Schweitzer D, Peters S, Sauer L, Hammer M, Haueisen J - PLoS ONE (2015)

Comparison of the different fluorescent lifetime modelling approaches in a healthy volunteer.The fluorescence intensity as well as the fluorescence lifetimes τm (A) and τ1 (B) in spectral channel 1 are shown (154 x 154 pixels, 59 x59 μm2/pixel). The color scaling of the fluorescence lifetime plots is identical in each subfigure. The ETDRS grid is drawn on each subplot, and the mean values are given for each subfield of the grid. The fluorescence intensity image is the measured signal before binning.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507995&req=5

pone.0131640.g008: Comparison of the different fluorescent lifetime modelling approaches in a healthy volunteer.The fluorescence intensity as well as the fluorescence lifetimes τm (A) and τ1 (B) in spectral channel 1 are shown (154 x 154 pixels, 59 x59 μm2/pixel). The color scaling of the fluorescence lifetime plots is identical in each subfigure. The ETDRS grid is drawn on each subplot, and the mean values are given for each subfield of the grid. The fluorescence intensity image is the measured signal before binning.
Mentions: Fig 8A depicts the fluorescence intensity as well as the average fluorescence lifetime τm (Eq 13) and fluorescence lifetime τ1 (Fig 8B) in spectral channel 1 for the different fluorescence lifetime approximation models. In the case of the stretched exponentials, only two exponential functions were used, compared to the three exponential functions used in the other cases. Furthermore, the fluorescence lifetime of a stretched exponential is not directly comparable to the other approaches because it must be interpreted in conjunction with the corresponding β.

Bottom Line: Specifically, we introduce a new adaptive binning approach as an optimal tradeoff between the spatial resolution and the number of photons required per pixel.An overview of the visualization capabilities and a comparison of static and adaptive binning is shown for a patient with macular hole.FLIMX's applicability to fluorescence lifetime imaging microscopy is shown in the ganglion cell layer of a porcine retina sample, obtained by a laser scanning microscope using two-photon excitation.

View Article: PubMed Central - PubMed

Affiliation: Institute of Biomedical Engineering and Informatics, Technische Universität Ilmenau, POB 100565, 98694, Ilmenau, Germany.

ABSTRACT
Fluorescence lifetime imaging ophthalmoscopy (FLIO) is a new technique for measuring the in vivo autofluorescence intensity decays generated by endogenous fluorophores in the ocular fundus. Here, we present a software package called FLIM eXplorer (FLIMX) for analyzing FLIO data. Specifically, we introduce a new adaptive binning approach as an optimal tradeoff between the spatial resolution and the number of photons required per pixel. We also expand existing decay models (multi-exponential, stretched exponential, spectral global analysis, incomplete decay) to account for the layered structure of the eye and present a method to correct for the influence of the crystalline lens fluorescence on the retina fluorescence. Subsequently, the Holm-Bonferroni method is applied to FLIO measurements to allow for group comparisons between patients and controls on the basis of fluorescence lifetime parameters. The performance of the new approaches was evaluated in five experiments. Specifically, we evaluated static and adaptive binning in a diabetes mellitus patient, we compared the different decay models in a healthy volunteer and performed a group comparison between diabetes patients and controls. An overview of the visualization capabilities and a comparison of static and adaptive binning is shown for a patient with macular hole. FLIMX's applicability to fluorescence lifetime imaging microscopy is shown in the ganglion cell layer of a porcine retina sample, obtained by a laser scanning microscope using two-photon excitation.

No MeSH data available.


Related in: MedlinePlus