A novel method for fast and robust estimation of fluorescence decay dynamics using constrained least-squares deconvolution with Laguerre expansion

Abstract

We report a novel method for estimating fluorescence impulse response function (fIRF) from noise-corrupted time-domain fluorescence measurements of biological tissue. This method is based on the use of higher-order Laguerre basis functions (LBFs) and a constrained least-square (CLS) approach that addresses the problem of overfitting due to increased model complexity. The method was extensively evaluated on fluorescence data from simulation, fluorescent standard dyes, ex vivo tissue samples of atherosclerotic plaques, and in vivo oral carcinoma. Current results demonstrate that this new method allows for rapid and accurate deconvolution of multiple channel fluorescence decays without adaptively adjusting the Laguerre scale parameter. The appropriate choice of the scale parameter is essential for accurate estimation of the fIRF. The method described here is anticipated to play an important role in the development of computational techniques for real-time analysis of time-resolved fluorescence data from biological tissues and to support the advancement of fluorescence lifetime instrumentation for biomedical diagnostics by providing a means for on-line robust analysis of fluorescence decay.

Technique for real-time tissue characterization based on scanning multispectral fluorescence lifetime spectroscopy (ms-TRFS)

“…As shown in Fig. 4(b), the lifetime SD also decreased with higher signal and lower noise (larger averaging factors), which agrees with previously reported simulation results [12].…”

“…The iIRF characterizes the fluorescence pulse overall broadening due to optical dispersion and electronics [10]. For deconvolution we employed a fast algorithm (<1 ms per decay) previously reported by our group [12]. The algorithm is based on a constrained least-squares deconvolution with Laguerre expansion (CLSD-LE) method and has demonstrated robustness against noise.…”

“…As previously demonstrated by simulation, the computation time and lifetimes SD are affected by the additive Gaussian noise [12]. To evaluate the system's data processing performance two types of noises were evaluated: the Gaussian noise that was primarily introduced by the digitizer, and the Poisson noise that was introduced by the MCP-PMT.…”

Time-resolved fluorescence spectroscopy and ultrasound backscatter microscopy for nondestructive evaluation of vascular grafts

“…Fluorescence decay values (average lifetime, τ and second-order Laguerre coefficient, LC-2) were estimated using a constrained leastsquare deconvolution with Laguerre expansion technique. 6 UBM (40 MHz, single-element transducer, resolution -30 μm, axial; 60 μm, lateral) imaging scans were performed across regions containing the graft as well as regions without the graft for comparison. UBM data were analyzed as described in our previous work.…”

Design and evaluation of a device for fast multispectral time-resolved fluorescence spectroscopy and imaging

“…To determine the fluorescence IRF, a non-parametric model based on Laguerre expansion of kernels and a constrained least-squares deconvolution algorithm was employed as previously reported in Ref. 22. In brief, the IRF was decomposed onto an ordered set of discrete time Laguerre functions (LFs),…”