Entity

Time filter

Source Type

Orsay, France

Abi Haidar D.,Laboratoire IMNC | Abi Haidar D.,University Paris Diderot | Leh B.,Laboratoire IMNC | Zanello M.,Laboratoire IMNC | And 2 more authors.
Biomedical Optics Express | Year: 2015

During glioblastoma surgery, delineation of the brain tumor margins is difficult because the infiltrated and normal tissues have the same visual appearance. We use a fiber-optical fluorescence probe for spectroscopic and time domain measurements to assist surgeon in differentiating the healthy and the infiltrated tissues. First study was performed on rats that were previously injected with tumorous cells. Measurements of endogenous tissue fluorescence were performed on freshand fixed rat tumor brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analyzed. The study aimed at defining an optical index that can act as an indicator for discriminating healthy from tumorous tissue. © 2015 Optical Society of America.


Abi Haidar D.,Laboratoire IMNC | Abi Haidar D.,University Paris Diderot | Leh B.,Laboratoire IMNC | Allaoua K.,Laboratoire IMNC | And 14 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2012

During glioblastoma surgery, delineation of the brain tumour margins remains difficult especially since infiltrated and normal tissues have the same visual appearance. This problematic constitutes our research interest. We developed a fibre-optical fluorescence probe for spectroscopic and time domain measurements. First measurements of endogenous tissue fluorescence were performed on fresh and fixed rat tumour brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analysed. Fluorescence information collected from both, lifetime and spectroscopic experiments, appeared promising for tumour tissue discrimination. Two photon measurements were performed on the same fixed tissue. Different wavelengths are used to acquire two-photon excitation-fluorescence of tumorous and healthy sites. © 2012 SPIE.


Siebert R.,Laboratoire IMNC | Leh B.,Laboratoire IMNC | Charon Y.,Laboratoire IMNC | Charon Y.,University Paris Diderot | And 7 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2010

The complete resection of the brain tumour is crucial to the patient life quality and prognosis. An autofluorescence probe aiming at helping the surgeon to improve the completeness of the removal is being developed. Autofluorescence spectroscopy is a promising approach to define whether the tissue is cancerous or not. First ex vivo measurements have been realised on an animal model. After tumorous cell injection in rat brain, autofluorescence intensity is revealed from the extracted brain. These autofluorescence data are compared to results from a histological analysis of same brains. First indicators are identified that may have the ability to differentiate tumorous and healthy tissues. © 2010 Copyright SPIE - The International Society for Optical Engineering.


Leh B.,Laboratoire IMNC | Charon Y.,Laboratoire IMNC | Charon Y.,University Paris Diderot | Duval M.-A.,Laboratoire IMNC | And 6 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2010

Glioblastoma are brain tumors currently incurable, however, optimized treatment gives better prognosis and quality of life. In case of surgical treatment, there is still need to help surgeons to determine whether a tissue is tumorous or not. Within the framework of the design of a new autofluorescence probe for this issue, optically calibrated gel phantoms have been developed using "tumorous" inclusions in a "healthy" environment. Depending on "tumor" shape, size and localization, the sensitivity of the probe is evaluated. The probe sensitivity for fluorescence spectroscopy will be presented. The probe configuration is also taken into account and compared to simulated results. © 2010 Copyright SPIE - The International Society for Optical Engineering.


Leh B.,Laboratoire IMNC | Siebert R.,Laboratoire IMNC | Hamzeh H.,Laboratoire IMNC | Menard L.,Laboratoire IMNC | And 5 more authors.
Journal of Biomedical Optics | Year: 2012

Growing interest in optical instruments for biomedical applications has increased the use of optically calibrated phantoms. Often associated with tissue modeling, phantoms allow the characterization of optical devices for clinical purposes. Fluorescent gel phantoms have been developed, mimicking optical properties of healthy and tumorous brain tissues. Specific geometries of dedicated molds offer multiple-layer phantoms with variable thicknesses and monolayer phantoms with cylindrical inclusions at various depths and diameters. Organic chromophores are added to allow fluorescence spectroscopy. These phantoms are designed to be used with 405 nm as the excitation wavelength. This wavelength is then adapted to excite large endogenous molecules. The benefits of these phantoms in understanding fluorescence tissue analysis are then demonstrated. In particular, detectability aspects as a function of geometrical and optical parameters are presented and discussed. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE).

Discover hidden collaborations