WO2018014440A1

WO2018014440A1 - Oct-based in situ 3d printing skin repair equipment and implementation method therefor

Info

Publication number: WO2018014440A1
Application number: PCT/CN2016/098505
Authority: WO
Inventors: 王玲; 徐铭恩; 宋江新; 杜显斌
Original assignee: 杭州捷诺飞生物科技有限公司
Priority date: 2016-07-19
Filing date: 2016-09-09
Publication date: 2018-01-25
Also published as: CN106073788B; CN106073788A

Abstract

Equipment used for OCT-based in situ 3D printing skin repair and an implementation method therefor, using OCT technology to scan an area of skin injury, obtaining a high-resolution 3D OCT image of the skin damage; on the basis of the OCT image, designing and modeling a 3D bionic structure of a skin damage site, so as to make sure of the structural requirements of the skin repair relative to the interface with internal tissue layers and vasculature; then sending the modeled skin damage repair model data to a 3D bio-printer (17), and layering and printing the model, so as to realize rapid, precise in situ repair of a skin damage site. The present in situ 3D printing skin repair equipment and the implementation method therefor have the advantage of non-contact, non-damaging real-time imaging, meeting the requirements of high-resolution imaging of internal microstructure for in situ skin printing, obtaining information on blood vessel distribution and density within the dermis, and enabling formation of a 3D model closer to the actual structure and functionality of real skin.

Description

OCT-based in-situ three-dimensional printing skin repairing device and implementation method thereof

Technical field

The invention belongs to the field of biomedical engineering technology, and relates to an optical coherence tomography (OCT)-based three-dimensional printing device for skin repair and an implementation method thereof, in particular to an OCT-based original for skin repair. Bit 3D printing device and its implementation method.

Background technique

Three-dimensional (3D) printing is based on digital imaging technology to create three-dimensional solids through layered processing and superposition molding, while three-dimensional bio-printing (3D Bio-printing) is in 3D. On the basis of printing, using bio-ink (biocompatible materials, cells, growth factors, etc.) to print out the desired structure layer by layer, and then in vitro and in vivo to form a new technology of physiologically functional tissues or organs, It has great application prospects in solving tissue repair and lack of donor organs. At present, 3D bio-printing technology is still in its infancy, and it is developing along the direction of printing simple living organisms to complex life structures. The printable materials are related to stem cells, living cells, hydrogels and biocompatible polymer materials. Exceeding the traditional 3D printing space. 3D bioprinting printing methods include in vitro printing and in-situ printing. The 3D bioprinting research currently reported has adopted the method of in vitro printing. This method has many limitations in clinical application, firstly due to the printing materials involved. To living cells, in the printing process must ensure a high enough cell survival rate and strictly control the microenvironment of cell growth, but also need to consider how to maintain tissue growth and metabolism through vascularization and how to regulate the subsequent differentiation process, etc. The difficulty is very high; secondly, the tissue or organ printed in vitro is rich in mechanical properties due to the fluid-rich biological material, and it is difficult to transplant and fix it to the body tissue under strict aseptic conditions. In addition, the tissue is printed in vitro. Organs take a long time, and the shape of the defect may have changed during implantation, which may cause a mismatch in size during transplantation. In-situ 3D bio-printing can obtain sufficient living cells from the autologous cells of the patient through cell enrichment technology as printing materials, and then directly digitalize the image to repair the defect and customize the shape-fitted print repair. The treatment not only repairs the damaged tissue in time, but also ensures the minimally invasiveness of the repair in the body environment.

In theory, in-situ 3D bioprinting can be used for the repair and reconstruction of different tissues, but it is still in the early stage of research, mainly focusing on dermal tissue repair and bone and cartilage defect repair. Clinical medical research has shown that large areas of skin defects can cause fluid loss, electrolyte imbalance, hypoproteinemia and serious infections. If the skin defect is larger than 4cm, the wound can not heal itself. The traditional treatment method is commercial skin or autologous skin. Transplantation repair, but the source and size of the materials required for this method are limited, and the preparation time is long. In the case of severe patient condition, the treatment timing may be delayed and the life of the patient may be endangered, and the portability of the in-situ 3D bio-printing technology may be , immediacy and mobility can solve the above problems well.

Selecting the appropriate imaging technology to obtain the microstructural information inside and outside the skin defect site is essential for constructing the three-dimensional model of the layered interface of the defect site and the internal vascular network, so as to achieve functionalized comprehensive skin repair, which is to implement skin in situ 3D. The premise of biological printing. However, common imaging techniques have the following problems when used for defect skin imaging: X-rays of micro-computed tomography (micro-CT) have large ion radiation to skin tissue, and imaging contrast is limited. Magnetic resonance imaging (MRI) technology takes too long to measure, the device is huge, and the imaging resolution is limited (on the order of mm). It is difficult to scan and measure the skin defect near the operating table; ultrasound imaging can realize real-time skin scanning. However, its imaging resolution is limited (about 0.5mm), the image speckle noise is large, and the fan scanning method is used to bring great challenges to the analysis and modeling of the skin defect after imaging; confocal microscopy and multiphoton microscopy ( Multiphoton microscopy (MPM) and other optical imaging methods have limited imaging depth. For example, confocal microscopy has a depth of about 100 μm for high-scattering samples and a depth of 400-500 μm for MPM. Public reports show that the current digital model based on these imaging techniques can print only 20 layers of cells, only a few hundred microns thick, far from meeting the actual needs; laser three-dimensional scanning technology can non-contact, quickly obtain skin defect parts The outer contours, but the microscopic information of the internal tissue structure of the skin cannot be obtained. Therefore, there is a need to develop a three-dimensional imaging technique that is suitable for penetration depth and capable of high-resolution imaging to cope with 3D bioprinting skin repair. Optical coherence tomography (OCT) technology is one of the most promising solutions to overcome the above various technical defects, because it can non-invasively acquire cross-sectional images of skin defect sites in real time, and the imaging resolution can be It reaches 1 to 15 μm and has an imaging depth of several mm, which provides a three-dimensional high-resolution image of the skin defect site, including both external three-dimensional contours and internal microstructure information.

Therefore, the present invention proposes an in-situ 3D bioprinting skin repair method based on optical coherence tomography (OCT), on the one hand, by scanning the skin lesion area by using the OCT system to obtain a three-dimensional skin with high resolution. OCT image, and based on the acquired OCT image, the three-dimensional biomimetic structure design and modeling of the scanned area defect skin. Since the OCT image has the internal structure information of the damaged skin, the constructed three-dimensional model can ensure the skin repair to the hierarchical interface within the tissue. Reconstruction requirements of the vascular network, and then send the modeled skin defect repair model data to the 3D bioprinting, layering and printing the model to achieve rapid, accurate and in vivo prediction of the damaged skin scanned by the OCT. On the other hand, by using the ability of 3D bioprinter to move in a wide range of three dimensions, it can overcome the limitation of OCT scanning range, realize high-precision and wide-range scanning of damaged skin, and complete the overall repair of damaged skin. In addition, the invention also innovatively adds a real-time imaging function to the scanning module of the OCT system and the printing module of the 3D bio-printer, which not only facilitates rapid recognition of damaged skin areas during scanning, but also implements a printing process. Real-time monitoring facilitates feedback optimization of print parameters.

Summary of the invention

An object of the present invention is to provide an in-situ three-dimensional printing apparatus based on optical coherence tomography (OCT) for skin repair in view of the deficiencies of the prior art.

The device of the invention comprises an OCT system, a 3D biological printing device;

The OCT system module includes a light source, a low coherence interference module, a sample scanning module, an interference signal detecting module, a timing control module, a data acquisition and an image processing analysis module. The light from the light source enters the low-coherence interference module through the optical fiber, and the probe light emitted by the low-coherence interference module enters the sample scanning module through the optical fiber, and then is focused by the scanning objective lens to the skin damage area, and the backscattered light path of the damaged area returns to the low coherence. The interference module, the low-coherence interference module generates an interference spectrum signal and sends the interference signal detection module through the optical fiber, and then completes the scanning and signal acquisition of the damaged area through the timing control module and the data acquisition and image processing analysis module, and finally utilizes the fast Fuli. The leaf transformation and the three-dimensional reconstruction algorithm obtain an image of the scanned area.

The low coherence interference module includes a reference arm and a portion of the sample arm; the light returned by the reference arm and the sample arm merges in a 2x2 coupler (recommended 50/50) to produce an interference spectrum signal.

The sample scanning module comprises a scanning probe, a three-dimensional moving arm of a 3D biological printer and a sample stage; wherein the scanning probe comprises a fiber collimator, a two-dimensional high-speed scanning galvanometer, and a micro A charge-coupled device (CCD) imaging system, a photodetection position calibration system, and a scanning objective lens, the micro CCD system includes a dichroic mirror, a collimating lens, and a CCD. The fiber collimator is located in front of the two-dimensional high-speed scanning galvanometer in the optical path, and the two are horizontally coaxial; the dichroic mirror is placed at an angle of 45 degrees to the horizontal plane, and is located below the two-dimensional high-speed scanning galvanometer and both are in the vertical direction. The axis; the collimating lens and the CCD are located in the direction of the light reflected by the dichroic mirror light path, and the three are horizontally coaxial; the scanning objective lens is located in the direction of the transmitted light of the dichroic mirror, and is coaxial with the dichroic mirror in the vertical direction for the scanning process. Real-time monitoring of samples and machine vision recognition.

The photodetection position calibration system is composed of four photoelectric position detectors mounted on a scanning objective base (for example, four corners), and the photoelectric detection position calibration system is used for position calibration of the scanning probe during scanning, so that Always maintain a fixed value H in the vertical direction.

Preferably, when adjusting the focal length of the collimating lens before the CCD, the imaging range of the CCD is slightly larger than the maximum scanning range of the two-dimensional high-speed scanning galvanometer, and the recommended size is 10% larger.

The interference signal detecting module is configured to collect an interference spectrum signal.

The timing control module is configured to control the triggering of the light source, the scanning timing of the two-dimensional high-speed scanning galvanometer in the sample scanning module, and the timing of the movement of the three-dimensional moving arm.

The data acquisition in the data acquisition and image processing analysis module is to collect OCT interference signal data through a high-speed data acquisition card, and the collected signal is transmitted to the PC end through the PCI bus, and the PC end passes data analysis processing and image reconstruction. , the cross-sectional image of the sample can be displayed in real time.

The printing parameter controllable 3D biological printing device mainly comprises a printing host, a central control module, a printing nozzle, a three-dimensional moving arm, and a printing forming platform. The print host is responsible for configuring print parameters, editing the print model, running the layering algorithm, sending the machining instructions and monitoring the print status. The central control module is responsible for receiving the information and processing instructions of the signal acquisition and image processing module feedback, and performing motion control on the three-dimensional moving arm. And the adjustment/opening and closing of the extrusion air pressure of the printing nozzle.

Further, the device of the present invention employs a swept-frequency OCT imaging system or a spectral domain OCT imaging system, but in either case, the sample scanning module requires scanning probe position calibration and continuous fast scanning.

The swept-frequency OCT imaging system uses a broadband swept source, and the interference signal detection module uses a photo-balance detector. The sweep frequency range of the broadband swept source is required to be between 80 nm and 220 nm, and is recommended to be between 100 nm and 140 nm to ensure a balanced axial imaging resolution and system spectral width matching.

The spectral domain OCT imaging system uses a broadband continuous light source, and the interference signal detection module uses a high-speed linear array spectral detector.

Another object of the present invention is to provide an implementation method of the above apparatus.

The method uses the OCT system to scan the skin lesion area, obtains a three-dimensional OCT image of the skin with high resolution, and designs and models the three-dimensional biomimetic structure of the skin defect part based on the OCT image. Since the OCT image has damaged internal structure information of the skin, Therefore, the constructed 3D model can ensure the reconstruction of the stratified interface and the vascular network in the tissue, and then send the modeled skin defect repair model data to the 3D bioprinter for layering and printing. Rapid, accurate, in-situ repair of damaged skin scanned by OCT;

Further, a linkage application method between OCT and three-dimensional bio-printer is proposed. By utilizing the ability of the three-dimensional moving arm of the 3D bio-printer to move over a wide range of three-dimensional movements, the limitation of the OCT scanning range can be overcome, and the high-precision and large-scale of the damaged skin can be realized. Scan to complete the overall repair of damaged skin;

In addition, the present invention also innovatively proposes a method of adding a real-time imaging function to the scanning module of the OCT system and the printing module of the 3D bio-printer, which not only facilitates the rapid recognition of the damaged skin area during scanning, but also realizes Real-time monitoring of the printing process, after the completion of the printing repair, the OCT scanning module can be selected to scan the repaired area, verify the quality of the repair and optimize the feedback parameters, or drive the 3D moving arm to move to In the next area, the next round of scanning and printing repair process is carried out.

The pre-scanning operation of the skin lesion area by using the OCT system specifically firstly images the skin area to be repaired by scanning the CCD system in front of the objective lens, and then uses the machine vision algorithm (the existing mature algorithm) to image the skin of the image area. To identify, if it is not damaged skin, drive the 3D moving arm to move to the next scanning area, continue imaging recognition; if it is damaged skin, drive the rotating motor and the 3D moving arm first between the scanning probe and the damaged skin Position calibration, then perform OCT scan imaging;

The OCT scan imaging probe light emitted by the low-coherence interference module enters the scanning probe through the optical fiber, and then is focused to the damaged skin region by the scanning objective lens, and performs a fast scanning in the imaging range from the initial point; after the scanning is completed, the scanning is completed. The signal acquisition and image processing module performs A/D conversion and image reconstruction on the acquired interference spectrum signal, and can generate an XZ two-dimensional gray sequence image, and then three-dimensional reconstruction of the obtained XZ two-dimensional gray sequence image by using a three-dimensional reconstruction algorithm. Build a scan The three-dimensional OCT image of the internal structural information of the region (such as sweat glands, blood vessels, etc.), and then based on the three-dimensional image for the three-dimensional biomimetic structure design and modeling of the skin defect site to ensure the skin repair to the internal layered interface and the reconstruction of the vascular network demand.

The layering of the model specifically refers to a certain thickness d along the Z-axis, and the three-dimensional model of the constructed skin defect is layered and sliced, and then printed by layer by layer according to the slice data by a 3D bioprinter to construct a sweat gland and a blood vessel. Structure of the skin tissue.

The thickness d referred to herein is the thickness of the slice, and d is slightly smaller than the diameter of the extruded wire of the printing head (recommended to be 70% to 80% of the diameter of the wire).

Advantageous effects of the present invention include:

(1) The in-situ skin repair system and method integrating skin wound scanning and in-situ printing technology can realize personalized, differentiated and instant skin repair compared with traditional tissue engineering technology.

(2) Proposed an OCT-based skin defect scanning method. The method has the advantages of non-contact and damage-free real-time imaging, and satisfies the requirement of high-resolution imaging of internal microstructures by skin in-situ printing, and can acquire the distribution and density information of hair follicles and blood vessels in the dermis layer of the skin, and is convenient for constructing a structure closer to real skin and A three-dimensional model of functionality. And the OCT device is small in size, which can meet the requirements of in-situ printing for device portability.

(3) Based on OCT and 3D bioprinting, the sub-regional scanning-in-situ printing method can reduce the requirement of cell enrichment speed in direct large-area printing, and make the overall skin in situ repair operation smoother.

(4) It is proposed to add real-time imaging function to the scanning module of OCT system and the printing module of 3D bio-printer, which not only facilitates the rapid recognition of damaged skin area during scanning, but also realizes real-time monitoring of printing process. It is conducive to the timely feedback optimization of printing parameters. It saves the time of scanning and printing, and guarantees the quality of print repair.

DRAWINGS

1 is a schematic block diagram of an in situ three-dimensional bioprinting skin repair system based on optical coherence tomography;

Figure 2 (a) is a detailed illustration of an in-situ three-dimensional bioprinting skin repair system based on swept-frequency source coherence tomography (SS-OCT);

Figure 2(b) is a detailed illustration of a in-situ three-dimensional bioprinting skin repair system based on spectral domain coherence tomography (SD-OCT);

Figure 3 is a device diagram of 3D bioprinting;

Figure 4 (a) is a print module device diagram;

Figure 4 (b) is a front elevational view showing the positional distribution of the function modules of the printing module;

Figure 5 is a flow chart of the in-situ scan print repair operation of the damaged skin;

Fig. 6 is a three-dimensional reconstruction image of a skin OCT grayscale image (Fig. 6(a)) containing blood vessels and a blood vessel internal distribution (Fig. 6(b)).

detailed description

The present invention will be further described below with reference to the accompanying drawings.

The in-situ three-microbial printing system includes a three-dimensional biological printing device based on optical coherence tomography scanning and a biological three-dimensional printing device with controllable printing parameters, and a block diagram thereof is shown in FIG. 1 .

Figure 2(a) is a detailed view of an in-situ three-dimensional bioprinting system based on swept-frequency source coherence tomography (SS-OCT), and Figure 2(b) is based on spectral-domain coherence tomography (SD-OCT). A detailed view of the in-situ 3D bioprint skin repair system. The working principle is: the light emitted by the light source 1 (in which FIG. 2(a) is a swept frequency source, and FIG. 2(b) is a broadband light source) is divided into two paths by a 1×2 fiber coupler 2, one of which is a reference arm, and the light passes through The fiber circulator 3, the fiber polarization controller 4 and the collimating lens 5 are directly incident on the plane mirror 6 and then returned to the original path, and the other path is the sample arm, and the light passes through the fiber circulator 3, the fiber polarization controller 4, the collimator lens 5 and the X. The galvanometer 7, the Y galvanometer 8, the dichroic mirror 9 (full penetration of the probe light, and the light of the ring LED 10 are all inverted), the scanning objective lens 11 with the illumination of the ring LED 10 is incident on the sample 12, and the sample 12 is placed. On the sample stage 13 where the limb can be fixed, the backscattered and reflected light of the sample is divided into two paths when passing through the dichroic mirror 9, and the light emitted by the LED is reflected and then enters the micro through the collimator lens 5. In the CCD 14, the real-time imaging of the sample can be realized, and the other light is the OCT detection light, and after the sample is scattered and reflected, the light returning through the circulator 3 and reflected by the reference arm is passed through a 2×1 fiber coupling. After the device, the interference signal is detected by the detector 15 (where Fig. 2(a) is the photodetector, and Fig. 2(b) is the light. Instrument) and then converted into electrical signals collected by the data acquisition and image processing module 16, the processing. The processed data information is sent to the 3D bioprint 17.

3 is a device diagram of 3D bio-printing, mainly including a print host 18, a central control mode Block 19, printing module 20, rotating electrical machine 21, X/Y/Z moving arm 22, printing platform 23, and independent temperature control system 24. The print host 18 is responsible for configuring print parameters, editing the print model, running the layering algorithm, sending the machining instructions, and monitoring the print status. The center control module 19 is responsible for receiving the machining instructions and moving the rotary motor 21, the X/Y/Z moving arm 22 Control, and adjustment/opening and closing of the extrusion air pressure to the printing module 20, the independent temperature control system 24 is responsible for regulating the temperature of the printing module 20.

4(a) is a device diagram of the printing module 20, including two parts of an OCT scanning probe 25 and a printing head 26, wherein the scanning probe 25 is composed of a collimating lens 5, an X galvanometer 7, a Y galvanometer 8, a micro CCD 14, and two The color mirror 9 is provided with an objective lens 11 illuminated by the annular LED 10 and four photoelectric position detectors 27 fixed on the objective lens mounting base; the printing head is composed of a ring-shaped LED 10, a printing cylinder and a needle 28, and two symmetrically distributed The micro imaging module 29 is constructed. The size of the scanning probe 25 is the same as the size of the printing head 26, and the two can be integrated and fixed on the rotary electric machine 21 side by side, and then integrally fixed on the X/Y/Z moving arm 22 of the three-dimensional printer. During operation, the OCT scanning probe 25 is operated. After the scan is completed and the print host 18 receives the processed data information and completes the print settings, it first sends an instruction to the central control module 19, instructing the X/Y/Z shift arm to move the print head 26 to the beginning of the OCT scan probe 25. The position is then sent to the central control module 19 to control the X/Y/Z moving arm 22 and the print head 26 to complete the in-situ print repair of the current OCT scan area. In addition, in order to facilitate real-time monitoring of the printing situation, two symmetrically distributed miniature imaging modules 29 with circular LED 10 illumination can be integrated under the print head 26 and processed by the PID control algorithm to eliminate optical jitter.

Figure 4(b) is a front elevational view showing the positional distribution of the functional modules of the printing module.

Figure 5 is a flow chart of the damaged skin in situ scan print repair. In the repair of damaged skin by the system, the skin is first imaged by scanning the CCD system in front of the objective lens, and then the two-dimensional gray scale of the skin of the imaging area is identified by machine vision to determine whether the imaged area is a damaged skin area, if If the skin is not damaged, the three-dimensional moving arm is driven to move to the next scanning area to continue imaging recognition; if it is damaged skin, the rotating motor and the three-dimensional moving arm are first calibrated to the position between the scanning probe and the damaged skin, so that The relative position between the two remains vertical and the distance is a fixed value H. Then the OCT scan imaging is performed, and after the signal acquisition and image processing, the in-situ print repair process is triggered. After the repair is completed, the OCT scan module can be selected to be triggered. Repair area scan imaging, verify the quality of the repair and optimize the feedback of the print parameters, if the printed area partially collapses or Problems such as uneven material distribution, the printing parameters can be modified until the problem is solved. It is also possible to drive the 3D moving arm to move to the next area for the next round of scanning and printing repair process.

Figure 6 is a two-dimensional cross-sectional image of a skin OCT containing blood vessels and a three-dimensional skin vascular reconstruction image (field of view: 3 mm x 3 mm).

work process:

The scanning probe is fixed on the rotatable motor, and then fixed together with the rotating motor on the three-dimensional moving arm of the 3D biological printer. Before scanning imaging, a micro CCD imaging system can be constructed in front of the scanning objective for the convenience of the operator. Imaging the damaged area. In addition, by selecting the focal length of the collimating lens placed in front of the CCD, the imaging range of the CCD is slightly larger than the maximum scanning range of the two-dimensional scanning galvanometer (recommended 10mm × 10mm). 10%, then discriminate whether the imaged area is a damaged skin area according to the two-dimensional gray scale of the skin of the imaged area by machine vision. If it is not the damaged skin area, the scanning probe is moved in the X or Y direction to the bottom by driving the three-dimensional moving arm. A scanning area continues imaging recognition, and the moving distance is the maximum scanning range of the two-dimensional scanning galvanometer in the X or Y direction (recommended 10 mm). In the case of damaged skin, the computer sends an instruction to the OCT scan control system to calibrate the position between the scanning probe and the damaged skin site so that the position between the two remains vertical and is a fixed value H, calibrated The position parameters are detected in real time by four photoelectric position detectors installed around the scanning module, and the measured data is transmitted to the programmable controller. After calculation, the controller sends a command to the rotating motor of the fixed scanning probe, and the rotating motor performs corresponding Rotating, thereby rotating the scanning probe until it is perpendicular to the scanned position, and then moving the scanning probe by driving the three-dimensional moving arm to ensure that the scanning probe is perpendicular to the surface of the sample and the distance from the surface of the sample is equal to H, so that subsequent damage is caused. The rest of the skin and the scanning probe are kept at H to ensure that the scanned image is clear and stable.

After the calibration is completed, the scanning controller drives the two-dimensional galvanometer to start scanning. At this time, the detection light emitted by the low-coherence interference module enters the scanning probe through the optical fiber, and then is focused by the scanning objective lens into the damaged skin area, starting from the initial point. In the imaging range (recommended 10mm×10mm) for fast scanning, after the scanning of one area module is completed, the obtained interference spectrum signal is A/D converted and image reconstructed by the signal acquisition and image processing module, and XZ two-dimensional can be generated. The gray scale sequence diagram, and then the three-dimensional reconstruction algorithm can be used to construct a three-dimensional OCT image containing the internal structure information of the scan area, and then the XY plane slice processing is performed on the constructed three-dimensional OCT image, and the processed image data is processed. The information feedback is sent to the printing host to complete the printing parameter setting. Finally, the printing host sends a command to control the printing nozzle, and the damaged skin area is repaired layer by layer according to the slice data. After the repair is completed, the printing module returns to the starting position of the scanning and printing. At the same time, you can choose to use the OCT to scan the repaired area again to verify the quality of the repair and optimize the feedback. You can also choose to trigger the 3D moving arm to drive the scanning probe to move to the adjacent area in the X or Y direction. The moving distance is The maximum scanning range of the 2D scanning galvanometer in the X or Y direction (recommended 10mm), enters the next micro CCD imaging recognition, scanning probe calibration, scanning and print repair process. The in-situ three-dimensional bioprinting repair of damaged skin can be achieved by following the scanning-repairing process of the continuous area described above.

The above embodiments are not intended to limit the present invention, and the present invention is not limited to the above embodiments, and it is within the scope of the present invention as long as it meets the requirements of the present invention.

Claims

OCT-based in-situ three-dimensional printing skin repair equipment, including OCT system, 3D biological printing equipment;

The OCT system module comprises a light source, a low coherence interference module, a sample scanning module, an interference signal detecting module, a timing control module, a data acquisition and an image processing analysis module; the light emitted by the light source enters the low coherence interference module through the optical fiber, and the low coherence interference The probe light emitted by the module enters the sample scanning module through the optical fiber, and then is focused to the skin damage area by the scanning objective lens. The backscattered light path of the damaged area returns to the low coherence interference module, and the low coherence interference module generates the interference spectrum signal to be sent through the optical fiber. The interference signal detecting module then completes the scanning and signal acquisition of the damaged area through the timing control module and the data acquisition and image processing analysis module, and finally obtains the image of the scanned area by using the fast Fourier transform and the three-dimensional reconstruction algorithm;

The control parameter controllable 3D biological printing device mainly comprises a printing host, a central control module, a printing nozzle, a three-dimensional moving arm, a printing forming platform; wherein the three-dimensional moving arm can have a large-scale three-dimensional moving capability, and the OCT scanning range is overcome. Limitation, high-precision and wide-range scanning of damaged skin, and complete restoration of damaged skin.
The OCT-based in-situ three-dimensional printed skin repair apparatus according to claim 1, wherein the scanning probe of the sample scanning module comprises a fiber collimator, a two-dimensional high-speed scanning galvanometer, a micro CCD imaging system, and photodetection. Position calibration system, scanning objective lens, micro CCD system includes dichroic mirror, collimating lens, CCD; fiber collimator is located in front of the two-dimensional high-speed scanning galvanometer in the optical path, the two are horizontally coaxial; dichroic mirror and horizontal plane Placed at a 45 degree angle, located under the two-dimensional high-speed scanning galvanometer and the two are coaxial in the vertical direction; the collimating lens and the CCD are located in the direction of the dichroic mirror light path, the three are horizontally coaxial; the scanning objective is located in the two directions The color mirror transmits light direction and is coaxial with the dichroic mirror in the vertical direction for real-time monitoring of samples and machine vision recognition during scanning.
The OCT-based in-situ three-dimensional printed skin repair apparatus according to claim 1, wherein said photodetection position calibration system is composed of a plurality of photoelectric position detectors mounted on a scanning objective lens base, and said photoelectric detection position calibration system It is used to align the position of the scanning probe during scanning so that it maintains a fixed value H in the vertical direction for optimal focus imaging.
The OCT-based in-situ three-dimensional printed skin repair apparatus according to claim 1, wherein when the focal length of the collimating lens before the CCD is adjusted, the imaging range of the CCD is made smaller than the maximum scanning range of the two-dimensional high-speed scanning galvanometer. Big.
The OCT-based in-situ three-dimensional printed skin repair device of claim 1 , wherein the micro-imaging module with annular LED illumination is integrated under the printing nozzle to realize real-time monitoring during printing.
The method for implementing an OCT-based in-situ three-dimensional printed skin repair device according to claim 1, wherein the method obtains a three-dimensional OCT image of the skin with high resolution by scanning the skin lesion region by using the OCT system, and is based on The OCT image is used to design and model the three-dimensional biomimetic structure of the skin defect site to ensure the skin remodeling requirements for the stratified interface and vascular network in the tissue, and then send the modeled skin defect repair model data to the 3D bioprinter. Model stratification and printing to achieve fast, accurate, in-situ repair of the injury site.
The method for implementing an OCT-based in-situ three-dimensional printed skin repair device according to claim 6, wherein the method simultaneously utilizes a micro-CCD imaging system of the OCT system sample scanning module and a micro imaging module of a 3D bioprinter print head. The real-time imaging function not only facilitates the rapid identification of damaged skin areas during scanning, but also enables real-time monitoring of the printing process.
The method for implementing an OCT-based in-situ three-dimensional printing skin repair device according to claim 6, wherein after the repair is completed, the OCT scanning module can be selected to scan the repaired area, and the quality of the repair and the feedback parameter optimization are verified. Or choose to drive the 3D moving arm to move to the next area for the next round of scanning and printing repair process.
The method for implementing an OCT-based in-situ three-dimensional printed skin repair device according to claim 6, wherein the pre-scanning operation of the skin lesion area by using the OCT system is specifically to first repair the CCD system before scanning the objective lens. The skin area is imaged, and then the machine vision algorithm is used to identify the two-level gray scale of the imaged area skin; if it is not damaged skin, the three-dimensional moving arm is driven to move to the next scan area to continue imaging recognition; if it is damaged skin, The rotating motor and the three-dimensional moving arm are first calibrated to the position between the scanning probe and the damaged skin, and then subjected to OCT scanning imaging;

The OCT scan imaging is performed by the low-coherence interference module to transmit the probe light through the optical fiber. The probe is then focused by the scanning objective lens into the damaged skin area, and the scanning is performed in the imaging range from the initial point; after the scanning is completed, the acquired interference spectrum signal is subjected to A/D conversion and image through the signal acquisition and image processing module. Reconstruction can generate XZ two-dimensional gray sequence map, then use the 3D reconstruction algorithm to reconstruct the XZ two-dimensional gray sequence image in three dimensions, construct a three-dimensional OCT image containing the internal structure information of the scan area, and then based on the three-dimensional image. The three-dimensional biomimetic structure design and modeling of the skin defect site is performed to ensure the skin remodeling needs for the stratified interface and the vascular network in the tissue.
The method for implementing an OCT-based in-situ three-dimensional printed skin repair device according to claim 6, wherein the layering of the model refers to a certain thickness d along the Z-axis, and the three-dimensional model of the constructed skin defect is performed. The slice was sliced and then printed layer by layer according to the slice data by a 3D bioprinter to construct a skin tissue containing structures such as sweat glands and blood vessels; wherein the slice thickness d was slightly smaller than the diameter of the extrusion line of the print head.