Imaging of glioma tumor with endogenous fluorescence tomography

Abstract

Abstract. Tomographic imaging of a glioma tumor with endogenous fluorescence is demonstrated using a noncontact single-photon counting fan-beam acquisition system interfaced with microCT imaging. The fluorescence from protoporphyrin IX ͑PpIX͒ was found to be detectable, and allowed imaging of the tumor from within the cranium, even though the tumor presence was not visible in the microCT image. The combination of single-photon counting detection and normalized fluorescence to transmission detection at each channel allowed robust imaging of the signal. This demonstrated use of endogenous fluorescence stimulation from aminolevulinic acid ͑ALA͒ and provides the first in vivo demonstration of deep tissue tomographic imaging with protoporphyrin IX.

In vivo micro-CT imaging of untreated and irradiated orthotopic glioblastoma xenografts in mice: capabilities, limitations and a comparison with bioluminescence imaging

“…In the second line (d-f), growth of U87MG tumor cells in the basal ganglia of a untreated mouse without central tumor necrosis and normal contrast enhancement is shown micro-CT-derived tumor volumes and histological analyses in a rat glioma model [5]. Micro-CT imaging of brain tumor growth in live mice has been reported sporadically [9][10][11][12] and most notably in combination with other modalities (e.g. PET) [9][10][11]24].…”

“…Thus few studies describe the use of micro-CT for in vivo imaging of orthotopic glioma xenografts in rats [5][6][7][8] as a stand alone technique or in combination with other techniques. Likewise, only few studies report the use of this method in live mice [9][10][11][12] and there is a lack of data regarding the diagnostic accuracy of micro-CT imaging of orthotopic glioma in live mice.…”

Quantification of in vivo fluorescence decoupled from the effects of tissue optical properties using fiber-optic spectroscopy measurements

“…The fluorescence measurements were also calibrated using an Intralipid liquid phantom with known μ a,x , μ s,x , and [PpIX]. The published 17 fluorescence quantum yield of 0.5% for PpIX was used to scale the quantitative fluorescence measurements to units of nm − 1 cm −1 . Repeatability performance tests were carried out as follows.…”

Imaging a photodynamic therapy photosensitizerin vivowith a time-gated fluorescence tomography system

“…For example, FDOT has been utilized as quantitative imaging for the localization of fluorophores in deeply seated tumors, as well as for therapy monitoring. [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] Among FDOT modalities, the time-domain (TD) modality provides superior sensitivity over continuous-wave FDOT and frequency-domain FDOT for detecting weak fluorescence signals. [33][34][35] It can quantify absolute concentration and depth of a fluorophore by analyzing time-of-flight measurements.…”