Fluorescence lifetime quantification in the ovarian epithelium.

<p>(A) Multiphoton intensity and FLIM images of endogenous fluorescence resulting from excitation at 890 nm of healthy and tumor ovarian tissues. The color map in (A) represents the weighted average of the two-term model components (τ_m = (<i>a</i>₁τ₁+<i>a</i>₂τ₂)/(<i>a</i>₁+<i>a</i>₂)) using the equation shown in the text. Scale bar = 10 µm (B) Quantitative analysis of fluorescent lifetime weighted mean component (τ_m) calculated only in the epithelium (white dotted line). 15 pixels in different epithelial cells from each image (15×3 = 45 measurements) were used to calculate lifetime values for tumor epithelial cells. † indicates comparison with normal tissues. ††, ** indicates a statistically very significant (p<0.01) difference following ANOVA analysis. N.: normal, Ade. : adenoma, Bord.: borderline, Adecar.: Adenocarcioma. (C) C1. Digital camera image of H&E stained ovarian tumor. Adenoma to borderline transformation is indicated. C2. Color maps of the fluorescence lifetime (τ_m), which illustrate the relatively longer lifetime values in malignant cells when compared to benign epithelium. Scale bar = 20 µm. C.3 Histogram plot (pixel frequency vs. τ_m) of the measures for the range of lifetime values of the two ROIs drawn in (C1) reveals the shift to longer lifetimes in malignant (red line) cells compared to benign epithelium (white line). Cells with mucin are indicated with white arrowhead. Ep: epithelium, St: stromal.