title: Laser line illumination scheme allowing the reduction of background signal and the correction of absorption heterogeneities effects for fluorescence reflectance imaging.
abstract: Intraoperative fluorescence imaging in reflectance geometry is an attractive imaging modality as it allows to noninvasively monitor the fluorescence targeted tumors located below the tissue surface. Some drawbacks of this technique are the background fluorescence decreasing the contrast and absorption heterogeneities leading to misinterpretations concerning fluorescence concentrations. We propose a correction technique based on a laser line scanning illumination scheme. We scan the medium with the laser line and acquire, at each position of the line, both fluorescence and excitation images. We then use the finding that there is a relationship between the excitation intensity profile and the background fluorescence one to predict the amount of signal to subtract from the fluorescence images to get a better contrast. As the light absorption information is contained both in fluorescence and excitation images, this method also permits us to correct the effects of absorption heterogeneities. This technique has been validated on simulations and experimentally. Fluorescent inclusions are observed in several configurations at depths ranging from 1 mm to 1 cm. Results obtained with this technique are compared with those obtained with a classical wide-field detection scheme for contrast enhancement and with the fluorescence by an excitation ratio approach for absorption correction.
authors.affiliation: University Grenoble Alpes, F-38000 Grenoble, France CEA, LETI, MINATEC Campus, 17 rue des Martyrs, Grenoble 38054, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Fantoni
authors.affiliation: University Grenoble Alpes, F-38000 Grenoble, France CEA, LETI, MINATEC Campus, 17 rue des Martyrs, Grenoble 38054, France.
authors.forename: Lionel
authors.initials: L
authors.lastname: Hervé
authors.affiliation: University Grenoble Alpes, F-38000 Grenoble, France CEA, LETI, MINATEC Campus, 17 rue des Martyrs, Grenoble 38054, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Poher
authors.affiliation: Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, ES-200 Boston, Massachusetts 02215, United States.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Gioux
authors.affiliation: University Grenoble Alpes, France CNRS, Gipsa-Lab, 11 Rue des Mathématiques, Saint-Martin-d'Hères 38400, France.
authors.forename: Jérôme I
authors.initials: JI
authors.lastname: Mars
authors.affiliation: University Grenoble Alpes, F-38000 Grenoble, France CEA, LETI, MINATEC Campus, 17 rue des Martyrs, Grenoble 38054, France.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Dinten
mesh_terms: D065638:Absorption, Radiation; D016477:Artifacts; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D007834:Lasers; D008029:Lighting / Q000295:instrumentation*; D008856:Microscopy, Fluorescence / Q000295:instrumentation*; D010783:Photometry / Q000295:instrumentation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D059629:Signal-To-Noise Ratio; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*