@inproceedings{62cc1bdff8f84fc781da0bb029f5610f,
title = "Single-photon spatial and energy resolution enhancement of a columnar CsI(Tl) / EMCCD gamma-camera using maximum-likelihood estimation",
abstract = "We examined the spatial resolution of a columnar CsI(Tl), single-photon imaging system using an approach that estimates the interaction position to better than the spread of the light distribution. A columnar scintillator was directly coupled to a 512×512 electron multiplying CCD (EMCCD) camera (16 μm pixels) binned at 2×2 to sample at 32 μm pixels. Optical photons from gamma-ray/scintillator interactions are sampled over multiple pixels. Resultant images show clusters of signal at the original interaction site, clusters from Cs & I K x-rays up to several hundred microns away, and clusters from collimator K x-rays. Also evident are depth-of-interaction effects which result in a broadening of the light distribution. These effects result in a degradation of spatial and energy resolution. Cluster pixel data was processed to better estimate the interaction position within the initial interaction cluster. Anger (centroid) estimation of individual gamma-ray events yielded spatial resolutions better than 100 μm; a result previously achievable only with pixellated semiconductor detector arrays. After proper calibration, depth-of-interaction (DOI) effects are corrected by performing maximum-likelihood 3D position and energy estimation of individual gamma-ray interactions.",
keywords = "CCD, Columnar CsI(Tl) scintillator, EMCCD, Gamma camera, Molecular imaging, Photon-Counting, SPECT",
author = "Miller, {Brian W.} and Barber, {H. Bradford} and Barrett, {Harrison H.} and Irina Shestakova and Bipin Singh and Nagarkar, {Vivek V.}",
year = "2006",
month = jun
day = "30",
doi = "10.1117/12.652650",
language = "English (US)",
isbn = "0819461857",
series = "Progress in Biomedical Optics and Imaging - Proceedings of SPIE",
booktitle = "Medical Imaging 2006",
note = "Medical Imaging 2006: Physics of Medical Imaging ; Conference date: 12-02-2006 Through 16-02-2006",
}