Abstract: A method for detecting fluorescence radiation from a fluorescence agent, includes: emitting light at an excitation wavelength range (72) to cause fluorescence radiation emission in the fluorescence agent, the fluorescence radiation having a fluorescence wavelength profile (73); detecting light at a first fluorescence wavelength range (74) as a first detection signal (S1); detecting light at a second fluorescence wavelength range (81, 91) as a second detection signal (S2); and numerically determining a third detection signal with an improved fluorescence-to-background radiation ratio based on the first detection signal (S1), the second detection signal (S2), and the fluorescence wavelength profile (73).

Abstract: Dynamic colorectal PDT methods, devices and photosensitizer compositions to treat abnormal cell growth in anal tissue such as perianal and intra-anal intraepithelial neoplasia grade III are presented. Dynamic colorectal PDT method comprises the steps of administering topically, intravenously or orally a photosensitizer composition; irradiating; monitoring treatment parameters before, during and/or after irradiation. Photosensitizer composition comprises Temoporfin and excipients/carriers, appropriate for the application method. An applicator is provided for colorectal PDT treatments enhancing irradiation delivery and monitoring treatment parameters. Preferably, applicator is made of a material, used to monitor the fluence rate simultaneously while doing optical spectroscopy. Measurement probe devices are provided for monitoring PDT treatment parameters in-vivo.

Abstract: A nanosensor for detecting an analyte can include a substrate, a photoluminescent nanostructure, and a polymer interacting with the photoluminescent nanostructure. The nanosensor can be used in in vivo for biomedical applications.

Abstract: Described are catheters associated with a hydrogel for release of a molecule of interest. The molecule of interest may be an antibody. Further described are sensors useful for detecting the presence or amount of an analyte, and associated methods. A sensor for use in detecting the presence or amount of an analyte may comprise a catheter having one or more apertures. The sensor may also include means for detecting binding of the analyte to an antibody.

Abstract: The present invention provides curcumin-derived near infrared (NIR) imaging probes. Upon interacting with amyloid ? aggregates, these probes undergo a range of changes, qualifying them as “smart” probes. The inventors have demonstrated that probes of the invention have the capacity to monitor the progression of Alzheimer's disease in an in vivo animal model. In addition, the present invention encompasses probes useful as PET imaging agents, MRI imaging agents and multimodal imaging agents, as well as related methods of detecting and imaging amyloid ? aggregates and plaques.

Abstract: An apparatus detects atherosclerotic plaques. The apparatus includes an electronic processing device that determines a level of fluorescence sensed by a sensor at a second infrared wavelength in response to exposure of at least part of an artery to radiation at a first infrared wavelength and determines a fluorescence indicator using the level of fluorescence. The fluorescence indicator is indicative of the presence, absence or degree of an atherosclerotic plaque.

Abstract: Embodiments of the present invention are directed to an optical sensor capable of measuring two analytes simultaneously with a single indicator system. In preferred embodiments, the sensor comprises a fluorescent dye having acid and base forms that facilitate ratiometric pH sensing, wherein the dye is further associated with a glucose binding moiety and configured to generate a signal that varies in intensity with the concentration of glucose.

Abstract: Systems and methods for imaging are presented. The method includes producing excitation light configured to induce fluorescence in an imaging agent that selectively binds to a target species in a region of interest (ROI) of a subject that also includes a background species. A first and a second spectral region are selected such that a determined difference between fluorescence corresponding to the target and the background species in the first spectral region differs from a corresponding difference in the second spectral region. First and second fluorescence images are generated from the fluorescence corresponding to the first and second spectral regions. Additionally, a fluorescence ratio for the background species in the first and second fluorescence image is determined. The first fluorescence image is then multiplied or divided with the determined ratio to generate an intermediate image that is subtracted from the second fluorescent image to reconstruct a background-subtracted image.

Abstract: Vessel perfusion and myocardial blush are determined by analyzing fluorescence signals obtained in a static region-of-interest (ROI) in a collection of fluorescence images of myocardial tissue. The blush value is determined from the total intensity of the intensity values of image elements located within the smallest contiguous range of image intensity values containing a predefined fraction of a total measured image intensity of all image elements within the ROI. Vessel (arterial) peak intensity is determined from image elements located within the ROI that have the smallest contiguous range of highest measured image intensity values and contain a predefined fraction of a total measured image intensity of all image elements within the ROI. Cardiac function can be established by comparing the time differential between the time of peak intensity in a blood vessel and that in a region of neighboring myocardial tissue both pre and post procedure.

Abstract: A disposable tubular end cap for a dermoscope for examining the skin of an animal. The end cap has one end for receiving light from and transmitting light to the dermoscope, a removable calibration target disposed at the other end having optical characteristics similar to a standard skin type, and an identifier disposed on the end cap. The identifier uniquely identifies the end cap and associates it with both data regarding light emitted from the skin of an animal and calibration data derived from the calibration target. Animal tissue may be examined to identify lesions using a plurality of wavelengths and a plurality of polarizations.

Abstract: The measuring unit computes at least one of an area and a perimetrical length of a polygon, based on three or more measuring points including an indeterminate point of which a position is changed by a move instruction input through an operation unit, wherein the measuring points are designated on the image by an instruction of a user input through the operation unit. The controller updates the position of the indeterminate point, when the move instruction is input through the operation unit after display the computational result, controls the measuring unit to recompute at least one of the area and the perimetrical length of the polygon based on the measuring points including the updated indeterminate point, and controls the display unit to display at least one of the recomputed area and the recomputed perimetrical length of the polygon, as recomputational result after updated the indeterminate point.

Abstract: Method, and the associated device, for examining a biological tissue, in particular dental tissue or tooth enamel of one or several teeth, the method including the steps of taking into account at least the fluorescence of the tissue detected in a first wavelength range and the fluorescence of the tissue detected in a second wavelength range. The device can be a surgery microscope with one or several filters. The filters can be swiveled into or out the Illumination beam path or the optical path of the light source of the device.

Abstract: A method for real-time, high-density physiological data collection includes automatically measuring, by a wearable device, one or more physiological parameters during each of a plurality of measurement periods, and upon conclusion of a measurement period, for each of the plurality of measurement periods, automatically transmitting by the wearable device data representative of the physiological parameters measured during that measurement period, to a server, the server configured to develop a baseline profile based on the data transmitted by the wearable device for the plurality of measurement periods. The measurement periods may extend through a plurality of consecutive days, and each of the consecutive days may include multiple measurement periods. At least some of the physiological parameters are measured by non-invasively detecting one or more analytes in blood circulating in subsurface vasculature proximate to the wearable device.

Abstract: A wearable device includes a detector configured to detect a response signal transmitted from a portion of subsurface vasculature, the response signal being related to binding of a clinically-relevant analyte to functionalized particles present in a lumen of the subsurface vasculature. Program instructions stored in a computer readable medium of the device, and executable by a processor, may cause the device to determine a concentration of the clinically-relevant analyte based on the response signal detected by the detector; determine whether a medical condition is indicated based on at least the concentration of the clinically-relevant analyte; and, in response to a determination that the medical condition is indicated, transmit data representative of the medical condition via the communication interface.

Abstract: Systems and methods of use for continuous analyte measurement of a host's vascular system are provided. In some embodiments, a continuous glucose measurement system includes a vascular access device, a sensor and sensor electronics, the system being configured for insertion into communication with a host's circulatory system.

Abstract: Disclosed is a spectrofluorimetrically detectable luminescent composition consisting essentially of at least one energy transfer acceptor lanthanide(III) complex having an emission spectrum maximum in the range from 300 to 2000 nanometers and a luminescence-enhancing amount of at least one energy transfer donor selected from the group consisting of a fluorophore, a lumiphore, an organic compound, a salt of an organic ion, a metal ion, a metal ion complex, or a combination thereof. Such energy transfer donor enhances the luminescence of at least one energy transfer acceptor lanthanide(III) complex, with the conditions that the emission spectrum of any energy transfer donor differs from that of its energy transfer acceptor lanthanide(III) complex; and such energy transfer donor can be dissolved to form a unitary solution in a solvent having an evaporation rate at least as great as that of water.

Abstract: Methods of measurement of biometric indicators in a mammalian subject are described. Biometric indicators of interest include hematocrit, plasma volume, volume of distribution, and glomerular filtration rate. The methods are especially applicable to subjects with rapid blood loss and to subjects with unstable hematocrits. Hematocrit may be measured by administering an injectate with a dynamic fluorescent marker and a static fluorescent marker, or a single static marker with two fluorescent tags, into the vascular system of the subject, and monitoring the emission intensities of the markers or fluorescent tags over a period of time. Hematocrit may then be calculated using a calibrated spectrometric analyzer by determining the raw ratio of the markers at T0, calculating the apparent hematocrit, and applying a correction factor.

Abstract: A pH detectable coating. The pH detectable coating includes a pH insensitive fluorescent dye and a pH sensitive fluorescent dye. The pH insensitive fluorescent dye and the pH sensitive fluorescent dye are attached to a surface. The ratio of the fluorescent intensity of the pH insensitive fluorescent dye to the fluorescent intensity of the pH sensitive fluorescent dye varies according to the pH of an environment into which the surface is placed.

Abstract: In a laser scanning method for measuring in vivo substances, wavelength of the anti-Stokes line is made greater than wavelength absorption band of the specific substance, the wavelength of the probe light is shifted from the wavelength of the anti-Stokes line by a shift amount of Raman scattering of the specific substance, and the wavelength of the Stokes light is shifted from the wavelength of the probe light by the shift amount of the Raman scattering of the specific substance. According to this, density (concentration and distribution) of lutein in an eye fundus is measured quantitatively and non-invasively from a signal strength level of the anti-Stokes line.

Abstract: A sensor (e.g., an optical sensor) that may be placed within a living animal (e.g., a human) and may be used to measure an analyte (e.g., glucose or oxygen) in a medium (e.g., interstitial fluid) within the animal. The sensor may include a sensor housing and a polymer graft including indicator molecules and covering at least a portion of the sensor housing. The opacity of the polymer graft may remain substantially the same (i.e., may have little or no variation) over time. The sensor may include a photodetector, and variation in the opacity of the polymer graft does not cause a significant change in a measurement signal output by the photodetector. The polymer hydrogel may be made of polymers including acrylic acid and/or polyethylene glycol.

Abstract: The invention provides methods and compositions for determining whether a subject containing a stent immobilized in a blood vessel has asymptomatic stent thrombosis or is at risk of developing clinically symptomatic stent thrombosis. In one approach, the method involves imaging a region of the blood vessel that contains the stent using a probe that contains a fluorochrome, for example, a near-infrared fluorochrome, and a targeting moiety that binds a molecular marker indicative of the presence of asymptomatic stent thrombosis or the development of symptomatic stent thrombosis. To the extent that the subject displays one or more such markers, the probe binds to the markers and increases the local concentration of the probe in the vicinity of the stent. The imaging method identifies those patients that display a higher density of such markers in the vicinity of the stent. As a result, those patients can be monitored for, and/or treated to prevent, symptomatic stent thrombosis.

Abstract: A device for applying a sensor to a measurement site on a patient's skin has a wall arrangement defining an applicator volume above the patient's skin The wall arrangement has a patient's side and a sensor side. At least one gas-permeable membrane separates the applicator volume into a first volume directed to the measuring site at the patient's side of the wall arrangement and a second volume separated from the patient's skin and directed to the sensor side of the wall arrangement.

Abstract: Provided is a biometric device including a light source unit arranged facing a first part on a surface of an organism and configured to irradiate the first part with excitation light, and a light-reception unit arranged facing a second part adjacent to the first part on the surface of the organism and configured to receive fluorescence light which is generated by the excitation light exciting a first body substance of the organism and emitted from the second part.

Abstract: A device (1) is provided that is configured to indicate the presence or absence of one or more biological entities in a biological sample. The device comprises a sampling portion (11), the sampling portion comprising flexible material adjustably conformable to a part of a human or animal body, at least a portion of the sampling portion being absorbent and configured to receive a biological sample directly from the body; and a test portion (12) in fluid engagement with the sampling portion, the test portion comprising one or more test zones (14). The sampling portion and test portion are configured such that at least a portion of the sample received by the sampling portion is transferable to the test portion such as to contact one or more of the test zones, and wherein each test zone is configured to indicate the presence or absence of one or more biological entities in the sample.

Abstract: Apparatus and methods are disclosed for multi-spectral imaging of tissue to obtain information about the distribution of fluorophores and chromophores in the tissue. Using specific spectral bands for illumination and specific spectral bands for detection, the signal-to-noise ratio and information related to the distribution of specific fluorophores is enhanced as compared to UV photography, which uses a single RGB image. Furthermore, the chromophore distribution information derived from the multi-spectral absorption images can be used to correct the fluorescence measurements. The combined fluorescence, absorption, and broadband reflectance data can be analyzed for disease diagnosis and skin feature detection.

Abstract: Presently described are systems and methods for the continuous, accurate, low cost measurement of the concentration of target molecule(s), e.g., analytes, such as metabolites and ions, using analyte-specific, light-emitting agents, e.g., fluorescent nanosensors.

Abstract: Methods for distinguishing between two interspersed biological tissues, for procedures such as surgical resection, include exposing the tissues to at least two components, a first of which components produces or is capable of producing a detectable signal, and the other of which components either blocks the produced signal of the first component or activates the first component to produce the detectable signal. One of the components is selectively taken up by one of the tissues at a concentration which is greater than the concentration by which it is taken up by the other tissue to provide a distinguishable difference in the detectable signal originating from the two tissues.

Abstract: Methods and systems are disclosed for determining an anaerobic threshold and/or an oxygen consumption rate in a human or animal subject. The methods include exposing a tissue of the subject to illumination radiation, collecting emitted radiation from the tissue, the emitted radiation including a portion of the illumination radiation reflected or transmitted from the tissue, processing the emitted radiation to form a spectrum of the tissue, and determining, based on the spectrum of the tissue, the anaerobic threshold and/or the oxygen consumption rate of the subject.

Abstract: An apparatus and method for noninvasive measurement of a fluorescent analyte concentration in the blood of a patient by exciting the blood and the analyte at two wavelength ranges and measuring the emission spectrum of the fluorescent analyte when (i) the difference of emission intensities at the excitation wavelength ranges of the fluorescent analyte is greater than that of background fluorophores, and (ii) when blood absorbance at the two excitation wavelength ranges is similar. An apparatus and method for measurement of a fluorescent analyte concentration in the blood of a patient is provided.

Abstract: An implantable fluorescent concentrator is configured to be inserted in vivo as a subcutaneous light source for optical absorption spectroscopy of surface-near tissue layers. As a result, certain and reliable results of the optical absorption spectroscopy are achievable. Furthermore, various analytes with different absorption properties are certainly and reliably quantifiable.

Abstract: The invention relates generally to in vivo collection of circulating molecules, tumor cells and other biological markers using a collecting probe. The probe is configured for placement within a living organism for an extended period of time to provide sufficient yield of biological marker for analysis. In some embodiments of the invention, active attraction of biological markers are provided. A partial or complete analytic/detection assembly may also be integrated with the probe.

Abstract: A fluorescence imaging device detects fluorescence in parts of the visible and invisible spectrum, and projects the fluorescence image directly on the human body, as well as on a monitor, with improved sensitivity, video frame rate and depth of focus, and enhanced capabilities of detecting distribution and properties of multiple fluorophores. Direct projection of three-dimensional visible representations of florescence on three-dimensional body areas advantageously permits view of it during surgical procedures, including during cancer removal, reconstructive surgery and wound care, etc. A NIR laser and a human visible laser (HVL) are aligned coaxially and scanned over the operating field of view. When the NIR laser passes over the area where the florescent dye is present, it energizes the dye which emits at a shifted NIR frequency detected by a photo diode. The HVL is turned on when emission is detected, providing visual indication of those positions.

Abstract: Systems and methods for imaging are presented. The method includes producing excitation light configured to induce fluorescence in an imaging agent that selectively binds to a target species in a region of interest (ROI) of a subject that also includes a background species. A first and a second spectral region are selected such that a determined difference between fluorescence corresponding to the target and the background species in the first spectral region differs from a corresponding difference in the second spectral region. First and second fluorescence images are generated from the fluorescence corresponding to the first and second spectral regions. Additionally, a fluorescence ratio for the background species in the first and second fluorescence image is determined. The first fluorescence image is then multiplied or divided with the determined ratio to generate an intermediate image that is subtracted from the second fluorescent image to reconstruct a background-subtracted image.

Abstract: Mobile clinicians conduct in-home patient visits utilizing on-site diagnostic and treatment equipment, where service is enhanced by the use of portable computing and communications equipment. A mobile care entity provides mobile clinicians preprogrammed portable computers. Each portable computer updates patient data in the local storage utilizing a wireless communications device to download updates from a central storage facility. The entity selects a mobile clinician and dispatches him/her to the patient's premises. The clinician visits the patient's premises accompanied by an assortment of electronic diagnostic and treatment devices. The mobile clinician utilizes various diagnostic devices to prepare machine-readable reports of related aspects of the patient's condition.

Abstract: A device for in vivo analysis includes: a reaction chamber to store a detecting reagent able to react with a sample collected in vivo; and optionally a labeled-substance chamber to store a labeled substance able to bind to at least a portion of a compound resulting from a reaction of the detecting reagent and the sample. The in-vivo imaging device, typically an autonomous capsule, may have a housing, the housing comprising a window; an illumination source located within the housing to illuminate a body lumen through the window; an imager to receive light reflected from the body lumen through the window; and a transmitter to transmit image data to a receiving system. The window is coated with liposomes containing a marker such that the imager may acquire images which include the marking.

Abstract: Embodiments of the present invention relates to analyte sensors. In particular, the preferred embodiments of the present invention relate to non-consuming intravascular glucose sensors based on fluorescence chemistry.

Abstract: The invention provides methods for visualizing renal tumors and for staging cysts during an operation by use of a fluorescent dye.

Abstract: A system for providing monitored radiation therapy has a high energy radiation source, apparatus for excluding uncontrolled ambient light, and apparatus for collecting light emitted from a subject. The system has apparatus for spectrally analyzing the collected light, and a processor for determining oxygenation or other metabolic function of tissue within the subject from spectral analysis of the collected light. The system monitors radiation therapy by providing a beam of high energy radiation; collecting Cherenkov and/or photoluminescent light from the subject, the light generated along the beam; spectrally analyzing the light; and determining oxygenation or metabolic function of tissue from the spectral analysis. Beam profile of the system is calibrated by imaging from multiple angles Cherenkov and/or photoluminescent light emitted by a phantom placed in the beam in lieu of a subject, captured images are analyzed to determine beam profile.

Abstract: A fluorescent endoscope apparatus includes an excitation light irradiation system for irradiating a living body with excitation light, a wavelength-selective transmission member which transmits light from the living body in a wavelength-selective manner, a photodetector which photoelectrically converts the selected and transmitted light, a wavelength selection control section which controls the wavelength-selective transmission member, to make it select and transmit light in a plurality of fluorescence detection wavelength regions and light in spectrum acquisition wavelength regions in a predetermined wavelength range that includes at least one of the fluorescence detection wavelength regions, a fluorescence image synthesizer for synthesizing images in the fluorescence detection wavelength regions, a display device for displaying the synthesized image, and an intensity distribution acquisition section which acquires the intensity distribution of light in the predetermined wavelength range.

Abstract: A system for detecting tumor margins includes a topical protease-specific, fluorescence imaging probe that is activatable by enzymatic activation to produce a visually differentiated signal upon topical application to a targeted cancer cell that secretes an enzyme that activates the protease-specific, fluorescence imaging probe, means for topically administering the imaging probe to the cancer cell; and an imaging device to detect activation of the imaging probe administered to the cancer cell.

Abstract: 2,5-Bis(benzoxazol-2?-yl)benzene-1,4-diol derivatives (Zinhbo derivatives) are used to detect zinc ions and have particular application in vivo and in vitro. Zinhbo derivatives upon excitation give a florescence response emission that can be used to determine the presence of zinc cation in solution. Zinhbo derivatives complexed with zinc cations upon excitation can produce a florescence response emission in the visible and near infrared range. Zinhbo derivatives complexed with zinc cations exhibit a large stoke shift between the excitation and emission wavelengths.

Abstract: A medical imaging system provides simultaneous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remain in a subject's blood stream for several minutes, allowing real-time imaging of the subject's circulatory system superimposed upon a conventional, visible light image of the subject. The system may provide an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide used to capture images. The system may be configured for use in open surgical procedures by providing an operating area that is closed to ambient light. The systems described herein provide two or more diagnostic imaging channels for capture of multiple, concurrent diagnostic images and may be used where a visible light image may be usefully supplemented by two or more images that are independently marked for functional interest.

Abstract: Provided are a transmissive suction mechanism (1), a suction hole (5), provided in the suction mechanism (1), through which skin is pulled into the suction mechanism (1), and an exhaust hole (4), provided in the suction mechanism (1), through which air in the suction mechanism (1) is removed so as to reduce the pressure in the suction mechanism (1).

Abstract: The present invention pertains to Method for monitoring a dialysis treatment of a patient, preferably for monitoring a haemodialysis, haemodiafiltration and/or peritoneal dialysis treatment of a patient, the method including the steps of: irradiating a sample of a dialysis fluid used in the dialysis treatment with linearly polarized irradiation light; detecting the intensity of the fluorescence light emitted by the dialysis fluid in a first polarization plane; detecting the intensity of the fluorescence light emitted by the dialysis fluid in a second polarization plane which is different from the first polarization plane; determining the anisotropy of the fluorescence light emitted by the dialysis fluid; and determining the concentration of at least one fluorophore in the dialysis fluid on the basis of both, the determined anisotropy and the intensity of the fluorescence light emitted by the dialysis fluid.

Abstract: The present invention generally provides methods and systems for performing in vivo flow cytometry by using blood vessels as flow chambers through which flowing cells can be monitored in a live subject in vivo without the need for withdrawing a blood sample. In some embodiments, one or more blood vessels are illuminated with radiation so as to cause a multi-photon excitation of an exogenous fluorophore that was previously introduced into the subject to label one or more cell types of interest. In some other embodiments, rather than utilizing an exogenous fluorophore, endogenous (intrinsic) cellular fluorescence can be employed for in vivo flow cytometry. The emission of fluorescence radiation from such fluorophores in response to the excitation can be detected and analyzed to obtain information regarding a cell type of interest.

Abstract: This invention relates to a method and apparatus for detecting a biological molecule associated with enzyme activity in a sample. The invention is applicable to detecting a microorganism associated with an enzyme in a sample such as water, food, soil, or a biological sample. According to a preferred embodiment of the method of the invention, a sample containing an enzyme of interest or a microorganism associated with the enzyme is combined with a suitable substrate, and a fluorescent product of the enzyme-substrate reaction is selectively detected. The fluorescent product is detected with a partitioning element or optical probe/partitioning element of the invention. In one embodiment the partitioning element provides for partitioning of only the fluorescent product molecule into the probe. The invention also provides an automated system for monitoring for biological contamination of water or other samples.

Abstract: Disease may be detected, monitored, etc. by detecting metabolic dysfunction in a patient's eyes. In one embodiment of an apparatus, an excitation light is generated by an excitation light source to induce autofluorescence in an ocular tissue (e.g., retinal tissue), wherein the excitation light excites flavoprotein autofluorescence (FA) and minimizes the excitation of non-flavoprotein autofluorescence. At least a single image representing the induced ocular tissue autofluorescence is captured. The at least single image is intensified to increase the signal strength of the ocular tissue autofluorescence. The at least single image is analyzed to generate an indicator of whether a patient has one or more of eye damage, a disease that causes eye damage, or to generate an indicator of the progression of a disease, an indicator of the effectiveness of a treatment, a personalized treatment for a subject, etc.

Abstract: A system of analysis with the naked eye and by fluorescence of a field in an illuminated area comprising a periodically-excited first low-remanence white light illumination source; a second light source for exciting fluorescent elements located in said field, active at least during part of the time periods when the first source is off; and a fluorescence analysis device active during time periods when the first source is off and the second source is on.

Abstract: The diagnosability of diseased parts is improved by precisely correcting fluorescence images without being affected by specular reflection and without being affected by thick blood vessels.

Abstract: A method for determining a ratio of hemoglobin absorption within a biological tissue using a handheld device is provided. The method includes focusing at least one light pulse into a predetermined area inside an object using at least one excitation wavelength, wherein a fluorescence signal is based on at least a local excitation optical fluence and properties of fluorophores in the predetermined area. The method further includes receiving a photoacoustic signal emitted by the object in response to the at least one light pulse, the photoacoustic signal being a product of the local excitation optical fluence, an optical absorption coefficient of hemoglobin, and an acoustic detection sensitivity. The method further includes determining the ratio of hemoglobin absorption based on a hemoglobin absorption coefficient that is based at least partially on the fluorescence signal and the photoacoustic signal.