CN112168144B - Optical coherence tomography system for burned skin - Google Patents
Optical coherence tomography system for burned skin Download PDFInfo
- Publication number
- CN112168144B CN112168144B CN202011107625.XA CN202011107625A CN112168144B CN 112168144 B CN112168144 B CN 112168144B CN 202011107625 A CN202011107625 A CN 202011107625A CN 112168144 B CN112168144 B CN 112168144B
- Authority
- CN
- China
- Prior art keywords
- sample
- optical
- oct
- information
- lens
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000012014 optical coherence tomography Methods 0.000 title claims abstract description 60
- 230000003287 optical effect Effects 0.000 claims abstract description 39
- 239000006185 dispersion Substances 0.000 claims abstract description 25
- 238000012545 processing Methods 0.000 claims abstract description 16
- 230000003595 spectral effect Effects 0.000 claims abstract description 6
- 239000000523 sample Substances 0.000 claims description 48
- 238000003384 imaging method Methods 0.000 claims description 37
- 230000017531 blood circulation Effects 0.000 claims description 25
- 239000013307 optical fiber Substances 0.000 claims description 24
- 238000001514 detection method Methods 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 10
- 231100000075 skin burn Toxicity 0.000 claims description 10
- 230000008859 change Effects 0.000 claims description 9
- 238000001228 spectrum Methods 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 7
- 238000005311 autocorrelation function Methods 0.000 claims description 6
- 238000000605 extraction Methods 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 6
- 238000002310 reflectometry Methods 0.000 claims description 5
- 230000035945 sensitivity Effects 0.000 claims description 5
- 239000000284 extract Substances 0.000 claims description 4
- 239000012472 biological sample Substances 0.000 claims description 3
- 238000005286 illumination Methods 0.000 claims description 3
- 238000004088 simulation Methods 0.000 claims description 3
- 206010054786 Skin burning sensation Diseases 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 claims 1
- 238000004364 calculation method Methods 0.000 claims 1
- 238000013480 data collection Methods 0.000 claims 1
- 230000001338 necrotic effect Effects 0.000 abstract description 3
- 238000010191 image analysis Methods 0.000 abstract description 2
- 208000027418 Wounds and injury Diseases 0.000 description 13
- 206010052428 Wound Diseases 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 7
- 238000003745 diagnosis Methods 0.000 description 6
- 230000006378 damage Effects 0.000 description 5
- 230000006870 function Effects 0.000 description 4
- 208000014674 injury Diseases 0.000 description 4
- 238000000701 chemical imaging Methods 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 206010053615 Thermal burn Diseases 0.000 description 2
- 230000001154 acute effect Effects 0.000 description 2
- 238000001574 biopsy Methods 0.000 description 2
- 210000004369 blood Anatomy 0.000 description 2
- 239000008280 blood Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000001917 fluorescence detection Methods 0.000 description 2
- 238000001727 in vivo Methods 0.000 description 2
- 238000000386 microscopy Methods 0.000 description 2
- 230000037311 normal skin Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000001931 thermography Methods 0.000 description 2
- 238000002604 ultrasonography Methods 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- 238000012800 visualization Methods 0.000 description 2
- 102000001554 Hemoglobins Human genes 0.000 description 1
- 108010054147 Hemoglobins Proteins 0.000 description 1
- 206010039580 Scar Diseases 0.000 description 1
- 238000002583 angiography Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 210000000601 blood cell Anatomy 0.000 description 1
- 210000004027 cell Anatomy 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000003759 clinical diagnosis Methods 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000010226 confocal imaging Methods 0.000 description 1
- 238000001218 confocal laser scanning microscopy Methods 0.000 description 1
- 238000004624 confocal microscopy Methods 0.000 description 1
- 238000002316 cosmetic surgery Methods 0.000 description 1
- 238000004925 denaturation Methods 0.000 description 1
- 230000036425 denaturation Effects 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- MOFVSTNWEDAEEK-UHFFFAOYSA-M indocyanine green Chemical compound [Na+].[O-]S(=O)(=O)CCCCN1C2=CC=C3C=CC=CC3=C2C(C)(C)C1=CC=CC=CC=CC1=[N+](CCCCS([O-])(=O)=O)C2=CC=C(C=CC=C3)C3=C2C1(C)C MOFVSTNWEDAEEK-UHFFFAOYSA-M 0.000 description 1
- 229960004657 indocyanine green Drugs 0.000 description 1
- 238000003331 infrared imaging Methods 0.000 description 1
- 238000010253 intravenous injection Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000017074 necrotic cell death Effects 0.000 description 1
- 230000000886 photobiology Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- 238000004393 prognosis Methods 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 238000012306 spectroscopic technique Methods 0.000 description 1
- 230000036575 thermal burns Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 210000005166 vasculature Anatomy 0.000 description 1
- 210000003462 vein Anatomy 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/0059—Measuring for diagnostic purposes; Identification of persons using light, e.g. diagnosis by transillumination, diascopy, fluorescence
- A61B5/0062—Arrangements for scanning
- A61B5/0066—Optical coherence imaging
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/0059—Measuring for diagnostic purposes; Identification of persons using light, e.g. diagnosis by transillumination, diascopy, fluorescence
- A61B5/0073—Measuring for diagnostic purposes; Identification of persons using light, e.g. diagnosis by transillumination, diascopy, fluorescence by tomography, i.e. reconstruction of 3D images from 2D projections
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/026—Measuring blood flow
- A61B5/0261—Measuring blood flow using optical means, e.g. infrared light
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/44—Detecting, measuring or recording for evaluating the integumentary system, e.g. skin, hair or nails
- A61B5/441—Skin evaluation, e.g. for skin disorder diagnosis
- A61B5/445—Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
- A61B5/7235—Details of waveform analysis
- A61B5/7253—Details of waveform analysis characterised by using transforms
- A61B5/7257—Details of waveform analysis characterised by using transforms using Fourier transforms
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Surgery (AREA)
- Public Health (AREA)
- Pathology (AREA)
- Veterinary Medicine (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Biophysics (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- Physiology (AREA)
- Dermatology (AREA)
- Mathematical Physics (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Psychiatry (AREA)
- Signal Processing (AREA)
- Hematology (AREA)
- Cardiology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses an optical coherence tomography system for burned skin, which comprises an optical coherence tomography instrument and a computer control system, wherein the optical coherence tomography instrument acquires interference signals of burned skin necrotic tissues in a target area, the computer control system performs image analysis and processing to obtain the burned depth and the burned area of the target area, and a three-dimensional image of the target area is synthesized for display, so that spectral interpolation or calibration is not required in data processing, and the system is simpler and more efficient; at the sample arm, flexible optical focusing is achieved by a variable focus lens. A dispersion compensation lens is added at the reference arm to compensate optical path dispersion and improve axial resolution, dispersion compensation is not needed in data processing, simplicity and high efficiency are achieved, and interference signals in a wave number space can be acquired in a high-fidelity mode in signal acquisition.
Description
Technical Field
The invention relates to the field of optical coherence tomography, in particular to an optical coherence tomography system for burned skin.
Background
Optical Coherence Tomography (OCT) is an emerging non-invasive optical detection technique that can provide high resolution three-dimensional images of skin tissue in the field of burned skin diagnosis. The basic structure of OCT is a low coherence interferometer, i.e., a broadband light source is divided into two parts, reference light and sample light, and when the optical path difference between the reflected reference light and the sample light backscattered through different layers of the sample conforms to the coherence length of the broadband light source, optical interference occurs, thereby obtaining an optical interference image. The coherence length of the OCT system using a light source is usually small, about 10 μm, and thus can provide high-resolution biological tissue information. OCT imaging techniques can be broadly divided into two categories: time Domain OCT (TDOCT) and Fourier Domain OCT (FDOCT). Time-domain OCT is a first generation OCT system, OCT line scanning is realized by moving a reference arm, however, the line imaging rate of the time-domain OCT system is relatively slow; the Fourier domain OCT system has higher imaging rate and sensitivity, can realize the visualization of skin tissue depth information, has the linear scanning speed of dozens of kHz and even MHz magnitude, and has very wide application prospect.
Since the last 60 s, a variety of burn deep diagnosis techniques have emerged in the field of burn wound diagnosis. The fluorescence detection technology is characterized in that a fluorescent substance is injected into veins, and the depth of a wound surface is evaluated according to the fluorescence intensity, the peak value and the time phase characteristics of the wound surface which are generated by excitation under different exciting light irradiation; the infrared thermal imaging technology is used for evaluating the burn depth of a wound surface by detecting the thermal radiation of different burned skins; based on ultrasonic imaging, researchers use B-ultrasonic to evaluate the burn depth, the main principle is to observe the boundary of burn tissues and judge according to the echo maps of normal skin and different burn tissues; the laser Doppler technology detects the blood cell flow condition in the wound tissue microvasculature by using Doppler frequency shift, and distinguishes the burn degree according to the relative flow velocity; the spectroscopic technique utilizes different attenuations of different spectra after being absorbed by blood in the wound surface to evaluate the burn depth; the reflection confocal imaging technology is characterized in that near-infrared light of a diode laser is focused on burned skin under a microscope, and the degree of burning is evaluated according to cell structures with different refractive indexes; photoacoustic microscopy imaging technique determines the depth of an acute thermal burn by imaging the total concentration of hemoglobin accumulated at the boundary of thermal injury to the vasculature in the blood
The prior related art to which this patent relates to the following references:
1、Niazi，Z.，et al.(1993).″New laser Doppler scanner，a valuable adjunct in burn depth assessment.″Burns 19(6)：485-489.
2、Calzavara-Pinton，P.，et al.(2008).″Reflectance confocal microscopy for in vivo skin imaging.″Photochemistry and photobiology 84(6)：1421-1430.
3、Kamolz，L.-P.，et al.(2003).″Indocyanine green video angiographies help to identify burns requiring operation.″Burns 29(8)：785-791.
4、Altintas，M.，et al.(2009).″Differentiation of superficial-partial vs.deep-partial thickness burn injuries in vivo by confocal-laser-scanning microscopy.″Burns 35(1)：80-86.
5、Erba，P.，et al.(2012).″Flux EXPLORER：a new high-speed laser Doppler imaging system for the assessment of burn injuries.″Skin Research and Technology18(4)：456-461.
6、Zhang，H.F.，et al.(2006).″Imaging acute thermal burns by photoacoustic microscopy.″Journal of biomedical optics 11(5)：054033.
7、Wang，X.-Q.，et al.(2010).″Ultrasound assessed thickness of burn scars in association with laser Doppler imaging determined depth of burns in paediatric patients.″Burns 36(8)：1254-1262.
8、Ruminski，J.，et al.(2007).″Thermal parametric imaging in the evaluation of skin burn depth.″IEEE transactions on biomedical engineering 54(2)：303-312.
9、Medina-Preciado，J.D.，et al.(2012).″Noninvasive determination of burn depth in children by digital infrared thermal imaging.″Journal of biomedical optics 18(6)：061204.
10、Brink，J.A.，et al.(1986).″Quantitative assessment of burn injury in porcine skin with high-frequency ultrasonic imaging.″Investigative radiology 21(8)：645-651.
11、Kalus，A.，et al.(1979).″Application of ultrasound in assessing burn depth.″The Lancet 313(8109)：188-189.
12、Goertz，O.，et al.(2010).″Orthogonal polarization spectral imaging：a tool for assessing burn depths？″Annals of plastic surgery 64(2)：217-221.
13、Thatcher，J.E.，et al.(2016).″Imaging techniques for clinical burn assessment with a focus on multispectral imaging.″Advances in wound care 5(8)：360-378。
at present, the 'gold standard' of burn diagnosis is still the histopathological biopsy, but the gold standard can not be practically applied to clinic, and the reasons are as follows: 1. biopsy is invasive to the body and may be unacceptable to the patient; 2. the histopathological changes of burns are dynamic and continuous within a certain time, and the damage degree can not be accurately predicted by performing single slice examination in an early stage; 3. a medical specialist with rich experience is needed, but if medical staff rely on limited experience to carry out initial visual diagnosis, the judgment accuracy of the burn area and the burn degree is only 60% and 51% respectively, the medical staff rely on visual observation to be a very subjective skin diagnosis system with low accuracy limited on the skin surface, and the learning cost and the medical risk are huge. The fluorescence detection technology requires intravenous injection of fluorescent substances; the infrared imaging technology can ensure the objectivity of measurement only under the conditions of constant environmental temperature and strict detection; b ultrasonic scanning has low resolution and needs to contact with a wound surface; the laser doppler technique and the spectral imaging technique can only acquire relatively coarse two-dimensional image information, which makes it difficult to objectively and comprehensively evaluate the burned skin condition. At present, the optical coherence tomography has also been used for skin imaging, and then the optical coherence tomography system based on the conventional spectrum technology has poor spectral linearity and resolution, and large attenuation of axial resolution and signal-to-noise ratio, while the swept-frequency optical coherence tomography system requires expensive light source and photodetector, which has high cost and technical difficulty.
Disclosure of Invention
The present invention is directed to an optical coherence tomography system for burned skin that solves one or more of the problems of the prior art, providing at least one useful alternative or creation.
The invention provides an optical coherence tomography system for burned skin, which comprises an optical coherence tomography instrument and a computer control system, has the advantages of non-invasive, three-dimensional and real-time dynamic imaging, and is simple and compact in system, excellent in performance and low in cost. The optical coherent imager obtains interference signals of burned skin necrotic tissues in a target area, and a computer control system obtains the burn depth and the burn area of the target area through image analysis and processing, and synthesizes a three-dimensional image of the target area for display. The system can indicate the change of the spatial structure of the skin caused by the denaturation of tissue protein before and after the skin burn, thereby providing micron-scale information about the boundary of normal skin tissue and necrotic tissue and the necrosis depth of the burned skin, achieving visualization and supporting clinical diagnosis, treatment and prognosis judgment.
The invention aims to solve the problems and provides an optical coherence tomography system for burn skin, which comprises: the device comprises a light source, an optical fiber coupler, a first collimating lens, a second collimating lens, a dispersion compensation module, a plane reflector, a zoom lens, a scanning galvanometer, a focusing lens, a sample to be detected, an optical detection module and a computer system. The optical fiber coupler is connected with the broadband light source, the reference arm first collimating lens, the sample arm, the second collimating lens and the optical detection module through optical fibers; in the reference arm, the first collimating lens, the dispersion compensation module and the plane mirror share an optical axis; in the sample arm, an included angle exists between the zoom lens and the scanning galvanometer, an included angle exists between the scanning galvanometer and the focusing lens, and the second collimating lens, the zoom lens and the focusing lens share an optical axis.
Further, the light source emits a light beam to enter the optical fiber coupler, and the optical fiber coupler divides the light beam into two beams; one beam enters a reference arm, passes through a first collimating lens and a dispersion compensation module in sequence and then is projected to a plane reflector, the plane reflector can be subjected to three-dimensional adjustment, and the light beam is reflected and returns to the optical fiber coupler along the original optical path; and the other beam enters the sample arm, passes through the second collimating lens and the zoom lens and then is projected to the scanning galvanometer, the scanning galvanometer angularly reflects the beam to the focusing lens, the focusing lens enables the beam to be condensed on the sample to be measured, and the back scattered light of the sample to be measured returns to the optical fiber coupler along the original optical path.
Furthermore, the reference light reflected back from the optical fiber coupler interferes with the back scattering light of the tested sample, the interference light enters the optical detection module, the optical detection module processes the interference light signal for multiple times and finally converts the interference light signal into an electric signal, the electric signal is transmitted to a computer system, and a three-dimensional, structural and blood flow image is obtained through software programming processing.
Furthermore, the light source adopts a broadband light source with the central wavelength of 1300nm and the bandwidth of 80 nm. The dispersion compensation module adopts a dispersion compensator to reduce the possibility of the existing artifacts, wherein the antireflection film wavelength band of the dispersion compensator is 800nm-1400nm, and the light-transmitting diameter is 22.8mm.
Furthermore, the zoom lens adopts a variable-focus liquid lens which is used for focusing fine adjustment before imaging to realize flexible optical focusing, wherein the variable-focus liquid lens has a dynamic range of 20 diopters and a numerical aperture of 1.6 mm.
Further, the light detection module adopts a linear wavenumber spectrometer to perform linear wavenumber sampling of the spectrum in the interference light processing. Before imaging is started, the computer system provides a depth imaging preview in an imaging area through a Labview platform, and the imaging area is scanned through a scanning galvanometer.
Furthermore, the computer system outputs data in a simulation mode through a Labview platform, so that a PCI function generation card controls a driving circuit of the scanning galvanometer to change the scanning angle of the scanning galvanometer and collect different position information of a tested sample, and a PCIe data acquisition card collects signals of each A line. The tested sample is a skin burn sample with unknown burn grade and is fixed on a lifting device with a moving range of 10cm in the depth direction.
Further, the computer system stores a plurality of items of collected information of the tested sample in a file form with a suffix of ". Oct" through a Labview platform to form a file, wherein the file comprises: the scanning range of the galvanometer, the total collection line number, the total collection frame number, the repeated collection times of each line A, the collection frame rate and the collection line rate. After the imaging acquisition, the computer system can play back the imaging process through Labview. And the computer system extracts information from the file with the suffix of the ". OCT" through Matlab software, and finally obtains multi-frame structure and blood flow information of the skin burn sample and a three-dimensional image through background noise processing, fourier transformation, simultaneous extraction of OCT amplitude and phase signals, automatic threshold adjustment and the like, wherein the multi-frame structure and blood flow information are stored in the form of the file with the suffix of the ". Dcm".
Further, the depth scattering information of the sample tissue can be obtained by performing inverse fourier transform on the collected interference light signal, wherein the inverse fourier transform is represented by the following formula:
wherein F -1 { f (a) } (x) denotes the inverse Fourier transform of the function f (a) with respect to the variable x, I OCT (k) Representing the raw spectral signal detected in k-space, r R The reflectivity of the reference arm field is indicated,
representing n simultaneously detected backscatter events, i.e. n scattering cross-sections, r S (z j ) Denotes from depth z j The detected jth backscattered sample arm field reflectivity, γ [2 (z-z) j )]Is a normalized time autocorrelation function, where γ is the normalized autocorrelation function name, exp [ -i2k [ -i 0 (z-z j )]Is due to the depth z j Of the j-th backscatter event of (a) 0 Is the intensity of illumination, z denotes depth, i denotes complex units, k 0 Representing the wave number.
Further, performing inverse Fourier transform on the detected k spectrum, wherein the OCT signal after Fourier transform contains amplitude and phase information,
the amplitude information of the obtained complex OCT information of the depth z-coded complex OCT function can be used for representing a structural OCT image, A (z) represents the amplitude,
indicating the phase.
Further, in the aspect of dynamic extraction of blood flow signals, the OCT complex information of adjacent B-scans is differentially calculated by repeating N times of B-scans at the same position, so as to obtain blood flow signals of a biological sample having dynamic information characteristics, specifically as follows:
wherein S i (z) represents the complex OCT information from the ith B-scan, since repeated B-scans are used and there is a time interval between the repeated B-scans, the time interval between adjacent B-scans should be long enough to observe the dynamic change of tissue blood flow, and the differential algorithm utilizes both the amplitude and phase information of OCT to obtain better blood flow sensitivity.
The invention has the beneficial effects that: the invention discloses an optical coherence tomography system for burned skin, which receives optical signals by using a linear wave number spectrometer and is used for sampling the linear wave number of a spectrum, spectral interpolation or calibration is not needed in data processing, and the system is simpler and more efficient; at the sample arm, flexible optical focusing is achieved by a variable focus lens. A dispersion compensation lens is added at the reference arm to compensate optical path dispersion, improve axial resolution, and is simpler and more efficient without dispersion compensation in data processing; acquiring a structural image and a blood flow image of the burned skin tissue by performing Fourier change and dynamic information extraction on the signal; by adopting a linear wave number spectrometer, higher signal sensitivity and image resolution can be kept in the axial direction; the variable-focus lens of the sample arm can flexibly adjust focusing when detecting the uneven burned wound, improves the focusing efficiency of the system, and can perform larger optical field imaging, thereby obtaining high-definition and high-fidelity skin structure and blood flow images; by adopting a linear wave number spectrometer and adding a dispersion compensator on a reference arm, interference signals in a wave number space can be acquired in high fidelity on signal acquisition, preprocessing such as interpolation or conversion and the like is not needed on data, fourier transform can be directly carried out on the signals, a three-dimensional image of a sample tissue is reconstructed, and the data processing is simpler and more efficient; the imaging system can acquire the three-dimensional structural image and the blood flow image of skin tissues simultaneously, can visually display the structural change of skin burn, can acquire functional blood flow information of the skin burn, and can evaluate the burn grade of the skin more comprehensively and accurately.
Drawings
The above and other features of the present invention will become more apparent by describing in detail embodiments thereof with reference to the attached drawings in which like reference numerals designate the same or similar elements, it being apparent that the drawings in the following description are merely exemplary of the present invention and other drawings can be obtained by those skilled in the art without inventive effort, wherein:
FIG. 1 is a block diagram of an optical coherence tomography system for burn skin.
Detailed Description
The conception, the specific structure and the technical effects of the present invention will be clearly and completely described in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the schemes and the effects of the present invention. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
Fig. 1 is a block diagram of an optical coherence tomography system for burn skin, and the system according to an embodiment of the present invention is described below with reference to fig. 1.
The invention provides an optical coherence tomography system for burnt skin, which specifically comprises: the device comprises a light source 1, an optical fiber coupler 2, a collimating lens 3 and a collimating lens 6, wherein the first collimating lens is the collimating lens 3, the second collimating lens is the collimating lens 6, a dispersion compensation module 4, a plane reflector 5, a zoom lens 7, a scanning galvanometer 8, a focusing lens 9, a sample to be detected 10, an optical detection module 11 and a computer system 12. The optical fiber coupler 2 is connected with the broadband light source 1, the reference arm collimating lens 3, the sample arm collimating lens 6 and the optical detection module 11 through optical fibers; in the reference arm, the collimating lens 3, the dispersion compensation module 4 and the plane mirror 5 share the same optical axis; in the sample arm, an included angle exists between the zoom lens 7 and the scanning galvanometer 8, an included angle exists between the scanning galvanometer 8 and the focusing lens 9, and the collimating lens 6, the zoom lens 7 and the focusing lens 9 share the same optical axis.
The light source 1 emits a light beam into the optical fiber coupler 2, and the optical fiber coupler 2 divides the light beam into two beams. One beam enters a reference arm, passes through a collimating lens 3 and a dispersion compensation module 4 in sequence and then is projected to a plane reflector 5, the plane reflector 5 can be adjusted in a three-dimensional mode, and the beam is reflected and returns to the optical fiber coupler 2 along the original optical path; the other beam enters the sample arm, passes through the collimating lens 6 and the zoom lens 7 and is projected to the scanning galvanometer 8, the scanning galvanometer 8 angularly reflects the beam to the focusing lens 9, the focusing lens 9 focuses the beam on the sample 10 to be measured, and the backward scattered light of the sample 10 to be measured returns to the optical fiber coupler 2 along the original optical path. The reference light reflected back from the optical fiber coupler 2 interferes with the back scattering light of the tested sample 10, the interference light enters the optical detection module 11, the optical detection module 11 processes the interference light signal for multiple times and finally converts the interference light signal into an electric signal, the electric signal is transmitted to the computer system 12, and a three-dimensional, structural and blood flow image is obtained through software programming processing.
The light source 1 adopts a broadband light source with the central wavelength of 1300nm and the bandwidth of 80 nm. The dispersion compensation module 4 adopts a dispersion compensator to reduce the possibility of the existing artifacts, wherein the antireflection film wavelength band of the dispersion compensator is 800nm-1400nm, and the light-transmitting diameter is 22.8mm. The variable-focus liquid lens 7 is a variable-focus liquid lens and is used for focusing fine adjustment before imaging to realize flexible optical focusing, wherein the variable-focus liquid lens has a dynamic range of 20 diopters and a numerical aperture of 1.6 mm. The light detection module 11 employs a linear wavenumber spectrometer to perform linear wavenumber sampling of the spectrum in the processing of the interference light. Before imaging begins, the computer system 12 provides a preview of depth imaging within the imaging region, including scanning by the scanning galvanometer 8, via the Labview platform. The computer system 12 outputs data through the Labview platform simulation, so that the PCI function generation card controls a driving circuit of the scanning galvanometer 8 to change the scanning angle of the scanning galvanometer 8 and collect different position information of the tested sample 10, and a PCIe data acquisition card collects signals of each a line. The sample 10 to be measured is a skin burn sample of unknown burn grade, and is fixed to a lifting device having a movement range of 10cm in the depth direction. The computer system 12 stores a plurality of pieces of information collected on the skin burn sample via the Labview platform in the form of a ". Oct" suffixed file comprising: the scanning range of the galvanometer, the total acquisition line number, the total acquisition frame number, the repeated acquisition times of each line A, the acquisition frame rate and the acquisition line rate. After the imaging acquisition, the computer system 12 may review the imaging process via Labview. The computer system 12 extracts information from the file with the suffix of ". OCT" through Matlab software, and finally obtains the multi-frame structure and blood flow information of the skin burn sample and a three-dimensional image through background noise processing, fourier transform, simultaneous extraction of OCT amplitude and phase signals, automatic threshold adjustment, and the like, wherein the multi-frame structure and blood flow information are stored in the form of the file with the suffix of ". Dcm".
Further, the depth scattering information of the sample tissue can be obtained by performing inverse fourier transform on the collected interference light signal, wherein the inverse fourier transform is represented by the following formula:
wherein F -1 { f (a) } (x) denotes the inverse Fourier transform of the function f (a) with respect to the variable x, I OCT (k) Representing the raw spectral signal detected in k-space, r R The reflectivity of the reference arm field is indicated,
representing n simultaneously detected backscatter events, i.e. n scattering cross-sections, r S (z j ) Denotes z from depth j The jth detected back scatterSample arm field reflectance of gamma 2 (z-z) j )]Is a normalized time autocorrelation function, where γ is the normalized autocorrelation function name, exp [ -i2k [ -i 0 (z-z j )]Is due to the depth z j Of the j-th backscatter event of (a) 0 For the intensity of illumination, z represents depth, i represents complex units, k 0 Representing the wave number.
Further, performing inverse Fourier transform on the detected k spectrum, wherein the OCT signal after Fourier transform contains amplitude and phase information,
the amplitude information of the obtained complex OCT information of the depth z-coded complex OCT function can be used for representing a structural OCT image, A (z) represents the amplitude,
indicating the phase.
Further, in the aspect of dynamic extraction of blood flow signals, the OCT complex information of adjacent B-scans is differentially calculated by repeating N times of B-scans at the same position, so as to obtain blood flow signals of a biological sample having dynamic information characteristics, specifically as follows:
wherein S i (z) represents the complex OCT information from the ith B-scan, since repeated B-scans are used and there is a time interval between the repeated B-scans, the time interval between adjacent B-scans should be long enough to observe the dynamic change of tissue blood flow, and the differential algorithm utilizes both the amplitude and phase information of OCT to obtain better blood flow sensitivity.
Although the present invention has been described in considerable detail and with reference to certain illustrated embodiments, it is not intended to be limited to any such details or embodiments or any particular embodiment, so as to effectively encompass the intended scope of the invention. Furthermore, the foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless represent equivalents thereto.
Claims (3)
1. An optical coherence tomography system for burning skin, the system comprising: the device comprises a light source, an optical fiber coupler, a first collimating lens, a second collimating lens, a dispersion compensation module, a plane reflector, a zoom lens, a scanning galvanometer, a focusing lens, a sample to be detected, an optical detection module and a computer system; the optical fiber coupler is connected with the broadband light source, the reference arm, the first collimating lens, the sample arm, the second collimating lens and the optical detection module through optical fibers; in the reference arm, the first collimating lens, the dispersion compensation module and the plane mirror share an optical axis; in the sample arm, an included angle exists between the zoom lens and the scanning galvanometer, an included angle exists between the scanning galvanometer and the focusing lens, and the second collimating lens, the zoom lens and the focusing lens share an optical axis;
the light source emits light beams to enter the optical fiber coupler, and the optical fiber coupler divides the light beams into two beams; one beam enters a reference arm, passes through a first collimating lens and a dispersion compensation module in sequence and then is projected to a plane reflector, the plane reflector can be subjected to three-dimensional adjustment, and the light beam is reflected and returns to the optical fiber coupler along the original optical path; the other beam enters a sample arm and is projected to a scanning galvanometer through a second collimating lens and a zoom lens, the scanning galvanometer angularly reflects the beam to a focusing lens, the focusing lens enables the beam to be condensed on a sample to be measured, and backward scattered light of the sample to be measured returns to the optical fiber coupler along an original optical path;
the reference light reflected from the optical fiber coupler interferes with the back scattering light of the tested sample, the interference light enters the optical detection module, the optical detection module processes the interference light signal for multiple times and finally converts the interference light signal into an electric signal, the electric signal is transmitted to a computer system, and a three-dimensional structure and a blood flow image are obtained through software programming processing;
the light source adopts a broadband light source with the central wavelength of 1300nm and the bandwidth of 80 nm; the dispersion compensation module adopts a dispersion compensator, wherein the wave band of an antireflection film of the dispersion compensator is 800nm-1400nm, and the light transmission diameter is 22.8mm;
the zoom lens adopts a variable-focus liquid lens which is used for focusing fine adjustment before imaging and realizing flexible optical focusing, wherein the variable-focus liquid lens has a 20-diopter dynamic range and a numerical aperture of 1.6 mm;
the optical detection module adopts a linear wave number spectrometer to sample the linear wave number of the spectrum in the interference light processing; before imaging is started, a computer system provides depth imaging preview in an imaging area through a Labview platform, and the imaging area is scanned through a scanning galvanometer;
the depth scattering information of the sample tissue can be obtained by performing inverse fourier transform on the collected interference light signal, wherein the inverse fourier transform is represented by the following formula:
wherein F -1 { f (a) } (x) denotes the inverse Fourier transform of the function f (a) with respect to the variable x, I OCT (k) Representing the raw spectral signal detected in k-space, r R The reflectivity of the reference arm field is indicated,
representing n simultaneously detected backscatter events, i.e. scattering cross-sections, r S (z j ) Denotes z from depth j The detected jth backscattered sample arm field reflectivity, γ [2 (z-z) j )]Is a normalized time auto-correlation function of,
wherein γ is a normalized autocorrelation function; exp [ -i2k 0 (z-z j )]Is due to the depth z j Of the j-th backscatter event of (a) 0 Is the intensity of illumination, z denotes depth, i denotes complex units, k 0 Represents the wave number;
performing an inverse Fourier transform on the detected k-spectrum, the Fourier transformed OCT signal containing amplitude and phase information,
and the amplitude information of the obtained complex OCT information of the depth z-coded complex OCT function can be used for representing the structural OCT image, A (z) represents the amplitude,
represents the phase;
in the aspect of dynamic extraction of blood flow signals, the OCT complex information of adjacent B-scans is differentially calculated by repeating N times of B-scans at the same position, so that a biological sample blood flow signal with dynamic information characteristics can be obtained, and the specific calculation is as follows:
wherein S i (z) represents the complex OCT information obtained by the ith B-scan, because the repeated B-scans are used, and the time intervals exist between the repeated B-scans, the time intervals of adjacent B-scans are long enough to observe the dynamic change of the tissue blood flow, and the differential operation simultaneously utilizes the amplitude and phase information of the OCT, so that the better blood flow sensitivity is achieved.
2. The optical coherence tomography system for burned skin as claimed in claim 1, wherein the computer system outputs data by Labview platform simulation, so that the PCI function generation card controls the driving circuit of the scanning galvanometer to change the scanning angle of the scanning galvanometer and collect different position information of the tested sample, and the collection of each A-line signal is collected by PCIe data collection card; the tested sample is a skin burn sample with unknown burn grade and is fixed on a lifting device with a moving range of 10cm in the depth direction.
3. The optical coherence tomography system for burned skin as claimed in claim 1, wherein the computer system stores a plurality of information of the collected tested sample in a file with ". Oct" as suffix by Labview platform to form a file, which comprises: the method comprises the following steps of (1) vibrating mirror scanning range, total collection line number, total collection frame number, repeated collection times of each line A, collection frame rate and collection line rate; after the imaging is collected, the computer system can replay the imaging process through Labview; and a computer system extracts information from the file with the suffix of the ". OCT" through Matlab software, and extracts OCT amplitude and phase signals through background noise processing and Fourier transform at the same time to finally obtain multi-frame structure, blood flow information and a three-dimensional image of the detected sample, wherein the multi-frame structure and the blood flow information are stored in the form of the file with the suffix of the ". Dcm".
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011107625.XA CN112168144B (en) | 2020-10-16 | 2020-10-16 | Optical coherence tomography system for burned skin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011107625.XA CN112168144B (en) | 2020-10-16 | 2020-10-16 | Optical coherence tomography system for burned skin |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112168144A CN112168144A (en) | 2021-01-05 |
| CN112168144B true CN112168144B (en) | 2022-12-20 |
Family
ID=73951222
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011107625.XA Active CN112168144B (en) | 2020-10-16 | 2020-10-16 | Optical coherence tomography system for burned skin |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112168144B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113017569B (en) * | 2021-03-09 | 2022-06-03 | 四川大学华西医院 | Skin wound healing condition inspection system based on spectral sub-band time domain autocorrelation |
| CN113349926B (en) * | 2021-05-31 | 2022-10-28 | 甘肃省人民医院 | Wound digital model construction system |
| CN114322797A (en) * | 2021-12-31 | 2022-04-12 | 浙江大学嘉兴研究院 | Optical detection cutting method and system for biological membrane tissue based on weak coherent interference |
| CN115950890B (en) * | 2023-03-15 | 2023-05-23 | 常州微亿智造科技有限公司 | Spectral domain optical coherence tomography detection method and system for industrial detection |
| CN117347317B (en) * | 2023-12-06 | 2024-03-08 | 常州微亿智造科技有限公司 | Large-depth spectrometer for frequency domain optical coherence tomography system and application thereof |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4265126A (en) * | 1979-06-15 | 1981-05-05 | General Electric Company | Measurement of true blood velocity by an ultrasound system |
| CN101297750B (en) * | 2008-05-09 | 2011-08-17 | 深圳职业技术学院 | Complex spectral domain optical coherence tomography method and system |
| WO2011037980A2 (en) * | 2009-09-22 | 2011-03-31 | Bioptigen, Inc. | Systems for extended depth frequency domain optical coherence tomography (fdoct) and related methods |
| US8921767B2 (en) * | 2010-08-02 | 2014-12-30 | The Johns Hopkins University | Automatic calibration of fourier-domain optical coherence tomography systems |
| US20140063506A1 (en) * | 2011-05-04 | 2014-03-06 | The Johns Hopkins University | Real-time, dispersion-compensated low-coherence interferometry system |
| US20130169971A1 (en) * | 2011-11-23 | 2013-07-04 | Wasatch Photonics, Inc. | Oct imaging system for curved samples |
| CN104523239B (en) * | 2015-01-12 | 2017-02-22 | 南京理工大学 | Full-depth spectral domain optical coherent tomography device and method |
| WO2017119437A1 (en) * | 2016-01-07 | 2017-07-13 | 株式会社ニデック | Oct signal processing device and oct signal processing program |
| CN106073788B (en) * | 2016-07-19 | 2023-03-17 | 杭州捷诺飞生物科技有限公司 | OCT-based in-situ three-dimensional printing skin repair equipment and implementation method thereof |
| EP3652512B1 (en) * | 2017-07-14 | 2021-09-01 | Wavesense Engineering GmbH | Optical apparatus |
| WO2019183838A1 (en) * | 2018-03-28 | 2019-10-03 | 深圳市太赫兹科技创新研究院 | Optical coherence tomography system |
| CN108732133B (en) * | 2018-04-12 | 2020-10-16 | 杭州电子科技大学 | Plant disease in-vivo nondestructive testing system based on optical imaging technology |
| CN110292361B (en) * | 2019-07-30 | 2024-04-30 | 佛山科学技术学院 | Ultra-wide-range skin imaging device and method |
-
2020
- 2020-10-16 CN CN202011107625.XA patent/CN112168144B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112168144A (en) | 2021-01-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112168144B (en) | Optical coherence tomography system for burned skin | |
| Kim et al. | Functional optical coherence tomography: principles and progress | |
| JP4241038B2 (en) | Optical method and system for tissue analysis | |
| US8788003B2 (en) | Monitoring blood constituent levels in biological tissue | |
| JP5579606B2 (en) | Apparatus, system and method for low coherence interferometry (LCI) | |
| Forsea et al. | Clinical application of optical coherence tomography for the imaging of non–melanocytic cutaneous tumors: A pilot multi–modal study | |
| KR101082477B1 (en) | Device for endoscopic functional optical coherent tomography | |
| Barton et al. | Dual modality instrument for simultaneous optical coherence tomography imaging and fluorescence spectroscopy | |
| CN110013212B (en) | Multi-parameter and multi-functional eye measuring instrument based on optical coherence tomography | |
| CN111481171A (en) | Multi-mode monitoring system and method for brain surgery | |
| JP5602363B2 (en) | Optical coherence tomography system | |
| CN112168136A (en) | Scanning-free three-dimensional optical coherence tomography angiography and tissue structure imaging system and method | |
| Zhu et al. | Resolution-matched reflection mode photoacoustic microscopy and optical coherence tomography dual modality system | |
| Ma et al. | Multiscale confocal photoacoustic dermoscopy to evaluate skin health | |
| CN210130811U (en) | Multi-parameter and multi-functional eye measuring instrument based on optical coherence tomography | |
| CN113670827A (en) | Polarization sensitive optical coherence-hyperspectral microimaging device and detection method thereof | |
| CN217310266U (en) | Skin imaging system | |
| US10682053B2 (en) | Ophthalmic photothermal optical coherence tomography apparatus | |
| Yu et al. | High‐Resolution Optical Coherence Tomography (OCT) for Skin Imaging | |
| Zimnyakov et al. | Laser tomography | |
| Kulkarni et al. | Optical coherence tomography: a novel tool for micron-resolution biomedical diagnostics | |
| Wang et al. | Optical microangiography: high-resolution 3-D imaging of blood flow | |
| Varghese et al. | Revolutionizing medical imaging: a comprehensive review of optical coherence tomography (OCT) | |
| Ding et al. | Probe fusion all-optic OCT-PAM dual-mode imaging system for biomedical imaging | |
| JP2022076601A (en) | Cartilage diagnosis device using oct |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |