Raman computed tomography (raman-ct) system and method

Abstract

The invention relates to an optical tomography scanning system ( 1 ) for 3D imaging of an object ( 100 ), for example an experimental rodent or a patient, using Raman scattered light from the object. A laser ( 10 ) and an optical configuration ( 20 ) for fixating the object and arranged for rotation (Θ) is provided, and an optical receiving part ( 30 ) receives Raman scattered light. The optical receiving part has a detector array ( 35 ) for receiving the Raman scattered light in two spatial dimensions (X, Z), and optical guide means ( 37 ) convey Raman scattered light to a spectrometer ( 38 ), where multiple spectra are recorded for the two spatial dimensions for each relative rotational position (Θ) of the object. A 3D image reconstruction of the object based on the multiple spectra at a plurality of relative rotational positions (Θ) of the object enables 3D tomographic imaging of the object, such as an experimental rat.

1 . An optical tomography scanning system for 3D imaging of an associated object using Raman scattered light from said object, said system comprising:
 a monochromatic light source configured to illuminate said object,   an optical configuration for fixating said object and configured to rotate said object to a plurality of relative rotational positions (Θ) between said object and the optical tomography scanning system,   an optical receiving part optically arranged relative to said object for receiving Raman scattered light from said object, the optical receiving part comprising:
 a detector array configured to receive the Raman scattered light in two spatial dimensions (X, Z), and 
 a plurality of optical guides configured to receive and convey said Raman scattered light to a spectrometer configured to record multiple spectra upon acquiring in said two spatial dimensions for each relative rotational position (Θ) of said object, 
   wherein the Raman scattered light from said object detected by said optical receiving part displays an anisotropic polar plot as a function of said relative rotational position (Θ) corresponding to the internal spatial structure of said object, and   a processor configured to generate a 3D image of said object based on said recorded multiple spectra based on a plurality of relative rotational positions (Θ) of said object, thereby using said anisotropic polar plot as a function of said relative rotational position (Θ) corresponding to the internal spatial structure of said object.   
     
     
         2 - 13 . (canceled) 
     
     
         14 . The optical tomography scanning system according to  claim 1 , wherein the scattered light from said object detected by said optical receiving part displays constructive interference near, or at, the detector array. 
     
     
         15 . The optical tomography scanning system according to  claim 14 , wherein said detector array is located approximately at least 5, 10, 15, 20, 25, or 30 cm from said object. 
     
     
         16 . The optical tomography scanning system according to  claim 1 , wherein said optical configuration for fixating said object is further configured to perform a relative longitudinal displacement (Z) of said object, said longitudinal displacement being substantially orthogonal to a rotational plane of said relative rotation (Θ) between said object and the optical tomography scanning system. 
     
     
         17 . The optical tomography scanning system according to  claim 1 , wherein the tomography scanning is simultaneously obtaining corresponding spectral information and spatial information about said object. 
     
     
         18 . The optical tomography scanning system according to  claim 1 , wherein the tomography scanning is based on backward-projection (BP) type measurements of the Raman scattered light in said optical receiving part. 
     
     
         19 . The optical tomography scanning system according to  claim 1 , wherein the Raman scattered light from said object being detected by said optical receiving part is forward scattered. 
     
     
         20 . The optical tomography scanning system according to  claim 16 , wherein said detector array is a line array, wherein the plurality of optical guides are arranged substantially in a rotational plane (Θ) of the object. 
     
     
         21 . The optical tomography scanning system according to  claim 16 , wherein said detector array is a point-like array, wherein an additional scanning (X) in a rotational plane (Θ) of the object is performed for acquiring multiple spectra in said two spatial dimensions. 
     
     
         22 . The optical tomography scanning system according to  claim 1 , wherein said detector array is a two-dimensional detector array, wherein Raman scattered light from said object is detected by said optical receiving part by simultaneous detection in both said rotational plane (Θ) and in an orthogonal (Z) dimension to said rotational plane. 
     
     
         23 . The optical tomography scanning system according to  claim 1 , wherein the detector array and the corresponding optical guides are mutually arranged for conveying a Raman spectrum in each optical guides. 
     
     
         24 . The optical tomography scanning system according to  claim 23 , wherein each optical guide comprises an optical fiber capable of conveying a Raman spectrum from said object. 
     
     
         25 . The optical tomography scanning system according to  claim 1 , wherein the 3D image reconstruction is performed using: a spectral unmixing technique, a spectral Library supervised reconstruction, an information entropy minimization technique, such as BTEM (band target entropy minimization), a multivariate curve resolution (MCR) technique, a vertex component analysis (VCA) technique, N-FINDR, a principal component analysis (PCA) technique, or any combinations thereof. 
     
     
         26 . The optical tomography scanning system according to  claim 1 , wherein the object is an animal body or a patient body, or part thereof, and the 3D image reconstruction is capable of resolving said spectral information and spatial information so as to provide a tissue differentiating resolution in the 3D image construction. 
     
     
         27 . A method for optical tomography scanning for 3D imaging of an object using Raman scattered light from said object, said method comprising:
 providing a monochromatic light source configured to illuminate said object,   fixating in an optical configuration said object, said optical configuration being configured to rotate said object to a plurality of relative rotational positions (Θ) between said object and an optical tomography scanning system,   arranging an optical receiving part optically relative to said object for receiving Raman scattered light from said object, the optical receiving part comprising:
 a detector array configured to receive the Raman scattered light in two spatial dimensions, and 
 a plurality of optical guides configured to receive and convey said Raman scattered light to a spectrometer configured to record multiple spectra upon acquiring in said two spatial dimensions (X, Z) for each relative rotational position (Θ) of said object, and 
   wherein the scattered light from said object detected by said optical receiving part displays an anisotropic polar plot as a function of said relative rotational position (Θ) corresponding to the internal spatial structure of said object, and   providing a processor configured to generate a 3D image reconstruction of said object based on said recorded multiple spectra based on a plurality of relative rotational positions (Θ) of said object, thereby using said anisotropic polar plot as a function of said relative rotational position (Θ) corresponding to the internal spatial structure of said object.