A control system and method for controlling the depth of hard tissue cutting based on laser

Abstract

The present invention discloses a control system and method for laser-based hard tissue cutting depth. The present invention combines OCT technology and laser ranging technology to identify the osteotomy boundary of tissue during the cutting process and calculate the real-time cutting depth. Then, the operation of the laser cutting module can be controlled by the real-time cutting depth. In this way, the present invention can achieve safe and accurate laser cutting control, thereby improving the cutting accuracy and safety. Therefore, it is very suitable for large-scale application and promotion in the field of hard tissue cutting.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical device control, and in particular relates to a control system and method for controlling the cutting depth of hard tissue based on laser. Background Art

[0002] In surgical treatment in the field of clinical medicine, hard tissue cutting is a very common and important operation. It is widely used in the fields of dentistry, maxillofacial surgery, orthopedics, bone tumors, etc. Traditional hard tissue (bone tissue) cutting is mainly completed by mechanical cutting methods, such as oscillating saws, wire saws, etc.; among them, traditional cutting methods have problems such as large trauma, large thermal damage to bone tissue and low precision. With the advancement of surgical technology, previous osteotomy methods or tools are difficult to meet clinical needs in some cases. Therefore, a hard tissue cutting method with less trauma and high precision is urgently needed.

[0003] At present, the application of non-contact laser osteotomy technology can well solve this clinical problem. Among them, laser cutting is non-contact cutting, and it can significantly improve the accuracy of osteotomy through the navigation system and medical robot technology in mature medical techniques. In addition, due to its unique physical and chemical cutting process, ultrafast laser causes very little damage to the surrounding bone tissue, which can better protect the activity of the surrounding bone tissue, thereby facilitating later bone healing and repair. However, with the application of this technology, how to control the depth of laser osteotomy is a practical problem faced by this technology in its application. Based on this, there is an urgent need to provide a laser-based hard tissue cutting depth control system. Summary of the Invention

[0004] The purpose of the present invention is to provide a control system and method for laser-based hard tissue cutting depth, so as to solve the problem that the existing technology cannot accurately control the laser cutting depth.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, a laser-based hard tissue cutting depth control system is provided, comprising:

[0007] An OCT imaging module, wherein the OCT imaging module is used to emit near-infrared weak coherent light to the target tissue at a preset emission frequency during the tissue cutting process, and receive near-infrared reflected light reflected by the target tissue, so as to generate multiple tissue structure images of the target tissue based on the near-infrared reflected light and send them to the data processing module;

[0008] A laser ranging module is used to emit a measuring laser to the target tissue according to a preset emission frequency during the tissue cutting process to measure multiple initial cutting depths of the target tissue and send the multiple initial cutting depths to the data processing module;

[0009] a data processing module, configured to obtain a real-time cutting depth of the target tissue based on a plurality of tissue structure diagrams and a plurality of initial cutting depths, and send the real-time cutting depth to a control feedback module;

[0010] The control feedback module is used to determine whether the real-time cutting depth reaches the depth threshold, and when it is determined that the real-time cutting depth does not reach the depth threshold, control the laser cutting module to operate according to the set cutting parameters until the obtained real-time cutting depth reaches the depth threshold, and then control the laser cutting module to stop operating.

[0011] Based on the above disclosed content, during the laser cutting process, the present invention first uses the OCT imaging module to emit near-infrared weak coherent light to the target tissue according to a preset emission frequency, thereby generating multiple tissue structure diagrams of the target tissue during the cutting process, and then uses the laser ranging module to continuously measure the tissue cutting depth during the cutting process, thereby obtaining multiple initial cutting depths; then, the multiple tissue structure diagrams and multiple initial cutting depths are used to calculate the real-time cutting depth of the target tissue; finally, the control feedback module can control the operation of the laser cutting module based on the aforementioned real-time cutting depth, that is, when the real-time cutting depth does not reach the depth threshold, the laser cutting module is controlled to operate according to the set cutting parameters, and then the cutting depth is continuously detected until the real-time cutting depth reaches the depth threshold, and the laser cutting module can be controlled to stop running.

[0012] Through the above design, the present invention combines OCT technology and laser ranging technology to identify the real-time cutting depth of tissue during the cutting process, and based on this, to control the operation of the laser cutting module; in this way, safe and accurate laser cutting control can be achieved, thereby improving the cutting accuracy and safety. Therefore, it is very suitable for large-scale application and promotion in the field of hard tissue cutting.

[0013] In one possible design, the data processing module is configured to sort the plurality of organizational charts in ascending order of the time interval between the generation time of the organizational charts and the current moment to obtain a first sorted sequence, and to sort the plurality of initial cutting depths in ascending order of the time interval between the measurement time of the initial cutting depths and the current moment to obtain a second sorted sequence;

[0014] a data processing module, configured to select first n tissue structure charts from the first sorting sequence, and select first n initial cutting depths from the second sorting sequence, where n is an integer greater than 1;

[0015] The data processing module is further configured to calculate the real-time cutting depth of the target tissue based on the first n tissue structure diagrams and the first n initial cutting depths.

[0016] In one possible design, the data processing module is configured to perform boundary cutting detection on each of the first n organizational structure charts to obtain a boundary detection result corresponding to each organizational structure chart, wherein the boundary detection result of any organizational structure chart is whether the cutting point reaches the boundary position between the hard tissue and the soft tissue in the target tissue, or does not reach the boundary position between the hard tissue and the soft tissue in the target tissue;

[0017] A data processing module is used to determine the osteotomy edge recognition constant corresponding to each tissue structure chart based on the boundary detection results of each tissue structure chart;

[0018] The data processing module is further configured to calculate the real-time cutting depth of the target tissue based on the first n initial cutting depths and all osteotomy edge identification constants.

[0019] In a possible design, each of the plurality of organizational charts corresponds to an initial cutting depth;

[0020] Among them, for any of the first n tissue structure diagrams, when the boundary detection result of any of the tissue structure diagrams is that the cutting point reaches the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to the any of the tissue structure diagrams is 1; when the boundary detection result of any of the tissue structure diagrams is that the cutting point does not reach the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to the any of the tissue structure diagrams is 0;

[0021] a data processing module for obtaining the calibrated bone surface distance of the target tissue and selecting, from the multiple initial cutting depths, an initial cutting depth corresponding to the tissue structure diagram with an osteotomy edge recognition constant of 1 as a target depth;

[0022] The data processing module is further used to calculate the real-time cutting depth of the target tissue based on all osteotomy edge identification constants, the first n initial cutting depths, the calibrated bone surface distance and the target depth.

[0023] In one possible design, the data processing module is used to calculate the real-time cutting depth of the target tissue according to the following formula (1);

[0024]

[0025] In the above formula (1), d′ represents the real-time cutting depth of the target tissue, d0 represents the distance to the calibrated bone surface, and d i represents the i-th initial cutting depth among the first n initial cutting depths, represents the osteotomy edge recognition constant corresponding to the i-th tissue structure diagram in the first n tissue structure diagrams, and D is the target depth.

[0026] In one possible design, the laser ranging module includes: a laser, a transmitting telescope, a reflector, a receiving telescope, a filter, a photoelectric element, an amplifying and shaping unit, and a time measurement unit;

[0027] The laser is configured to transmit a measuring laser to the transmitting telescope at a preset transmission frequency, and reflect each emitted measuring laser to the target tissue via a reflector, wherein each reflected laser generated by the target tissue is input to the photoelectric element via the reflector, the receiving telescope, and the filter, and the photoelectric element converts each input reflected laser into an electrical signal and transmits the signal to the amplification and shaping unit;

[0028] The amplifying and shaping unit is used to perform amplifying and shaping processing on each electrical signal to obtain each processed electrical signal, and transmit each processed electrical signal to the time measurement unit;

[0029] The time measurement unit is used to obtain multiple initial cutting depths based on the processed electrical signals.

[0030] In one possible design, the laser cutting module includes: a laser generator, an optical path transmission unit, and a focusing scanning unit;

[0031] The laser generator is used to emit cutting laser to the optical path transmission unit according to the set cutting parameters, wherein the cutting laser is transmitted to the focusing scanning unit through the optical path transmission unit and is focused to the cutting point on the target tissue by the focusing scanning unit.

[0032] In one possible design, the emission light path of the near-infrared weak coherent light of the OCT imaging module is on the same straight line as the emission light path of the cutting laser of the laser cutting module.

[0033] In a possible design, it further includes: a display module, wherein the display module is electrically connected to the OCT imaging module and the data processing module, and is used to visually display each tissue structure diagram and the real-time cutting depth.

[0034] In a second aspect, a method for controlling the depth of laser-based hard tissue cutting is provided, which is performed by a data processing module in the laser-based hard tissue cutting depth control system according to the first aspect or any possible design of the first aspect, and the method comprises:

[0035] Acquiring multiple histological diagrams and multiple initial cutting depths of the target tissue, wherein the multiple histological diagrams are generated by an OCT imaging module in the control system emitting near-infrared weak coherent light at a preset emission frequency toward the target tissue during a tissue cutting process, and based on near-infrared reflected light reflected by the target tissue, and the multiple initial cutting depths are measured by a laser ranging module in the control system emitting a measuring laser at a preset emission frequency toward the target tissue during a tissue cutting process;

[0036] Based on multiple tissue structure diagrams and multiple initial cutting depths, the real-time cutting depth of the target tissue is obtained, and the real-time cutting depth is sent to the control feedback module, so that the control feedback module determines whether the real-time cutting depth reaches the depth threshold. When it is determined that the real-time cutting depth does not reach the depth threshold, the laser cutting module is controlled to operate according to the set cutting parameters until the obtained real-time cutting depth reaches the depth threshold, and the laser cutting module is controlled to stop operating.

[0037] In the third aspect, an electronic device is provided as an example, comprising a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the laser-based hard tissue cutting depth control method as designed in the second aspect or any one of the two aspects.

[0038] In a fourth aspect, a storage medium is provided, on which instructions are stored. When the instructions are run on a computer, the laser-based hard tissue cutting depth control method as described in the second aspect or any possible design of the second aspect is executed.

[0039] In a fifth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, causes the computer to execute the laser-based hard tissue cutting depth control method as described in the second aspect or any possible design of the second aspect.

[0040] Beneficial effects:

[0041] (1) The present invention combines OCT technology and laser ranging technology to identify the osteotomy boundary of tissue during the cutting process and calculate the real-time cutting depth. Then, the real-time cutting depth can be used to control the operation of the laser cutting module. In this way, the present invention can achieve safe and accurate laser cutting control, thereby improving the cutting accuracy and safety. Therefore, it is very suitable for large-scale application and promotion in the field of hard tissue cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A schematic diagram of the architecture of a laser-based hard tissue cutting depth control system provided in an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of the laser ranging principle provided by an embodiment of the present invention;

[0044] Figure 3 A schematic structural diagram of a laser ranging module provided in an embodiment of the present invention;

[0045] Figure 4 A schematic diagram of optical path coupling of a control system provided by an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of the laser depth control sequence and decision-making process provided by an embodiment of the present invention;

[0047] Figure 6 A schematic diagram of cutting boundary detection provided by an embodiment of the present invention;

[0048] Figure 7 This is a flowchart of the steps of the laser-based hard tissue cutting depth control method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly introduced below in conjunction with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0050] It should be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element without departing from the scope of the exemplary embodiments of the present invention.

[0051] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may indicate three situations: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" that may appear in this document describes another type of association object relationship, indicating that two relationships may exist. For example, A / and B may indicate two situations: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this document generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0052] Example:

[0053] See also Figures 1 to 6 As shown, the laser-based hard tissue cutting depth control system provided in this embodiment may include, but is not limited to: an OCT imaging module, a laser ranging module, a data processing module, a control feedback module and a laser cutting module; wherein the laser cutting module is used to generate a laser beam (i.e., a cutting laser) with adjustable wavelength and power for cutting the target tissue (such as cutting bone tissue), while the OCT imaging module and the laser ranging module are used to generate a tissue structure diagram of the target tissue and detect the cutting depth during the cutting process, respectively; and the data processing module calculates the real-time cutting depth of the target tissue based on the data transmitted by the aforementioned OCT imaging module and the laser ranging module, and finally, the control feedback module can control the laser cutting module based on the real-time cutting depth, thereby achieving precise laser cutting.

[0054] Furthermore, the following embodiment discloses the specific working process of each of the aforementioned modules:

[0055] In a specific implementation, the OCT imaging module is used to emit near-infrared weak coherent light (such as 1300-1700nm, 100-110kHz near-infrared weak coherent light) to the target tissue according to a preset emission frequency during the tissue cutting process, and receive the near-infrared reflected light reflected by the target tissue, so as to generate multiple tissue structure diagrams of the target tissue based on the near-infrared reflected light and send them to the data processing module; wherein, the OCT (Optical Coherence Tomography) imaging module uses the basic principle of weak coherent light interferometer to detect the back reflection or several scattered signals of the incident weak coherent light at different depth levels of biological tissue, and then obtain a two-dimensional or three-dimensional structural image of the biological tissue by scanning; in this embodiment, the aforementioned preset emission frequency is a preset time interval, that is, the near-infrared weak coherent light is emitted to the target tissue at the preset time interval, so that different tissue structure diagrams of the target tissue are continuously obtained during the laser cutting process, and then each tissue structure diagram can be sent to the data processing module to realize the detection of the cutting boundary.

[0056] Optionally, for example, the emission path of the near-infrared weak coherent light of the OCT imaging module is on the same straight line as the emission path of the cutting laser of the laser cutting module. In this way, a real-time cutting tissue structure diagram of the target tissue can be generated during the cutting process, thereby realizing real-time cutting boundary detection during the cutting process.

[0057] At the same time, in this embodiment, the laser ranging module is used to emit a measuring laser to the target tissue according to a preset emission frequency during the tissue cutting process, so as to measure multiple initial cutting depths of the target tissue and send the multiple initial cutting depths to the data processing module; wherein, this embodiment emits red light with a wavelength of 655nm to the target tissue, thereby irradiating the surface of the target tissue for diffuse reflection, and then, by capturing the reflected light of the target tissue and calculating the time difference between the emitted measuring laser and the corresponding reflected laser, the laser transmission distance is calculated. In this way, each time a measuring laser is emitted, an initial cutting depth can be obtained, and the emission frequency of the measuring laser is the same as the transmission frequency of the near-infrared weak coherent light. Therefore, each of the multiple tissue structure diagrams corresponds to an initial cutting depth. Based on this, the real-time cutting depth of the target tissue can be calculated based on the aforementioned multiple tissue structure diagrams and multiple initial cutting depths, and the process is shown below.

[0058] That is, the data processing module is used to calculate the real-time depth of the target tissue based on the data transmitted by the aforementioned OCT imaging module and the laser ranging module, that is, the data processing module is used to obtain the real-time cutting depth of the target tissue based on multiple tissue structure diagrams and multiple initial cutting depths, and send the real-time cutting depth to the control feedback module; and the control feedback module is used to determine whether the real-time cutting depth reaches the depth threshold, and when it is determined that the real-time cutting depth does not reach the depth threshold, control the laser cutting module to operate according to the set cutting parameters until the obtained real-time cutting depth reaches the depth threshold, and control the laser cutting module to stop running; thus, through the aforementioned design, this embodiment uses OCT imaging technology and laser ranging technology to detect the real-time cutting depth during the target tissue cutting process, and based on this, performs real-time control of laser cutting, thereby achieving the purpose of precise laser cutting control.

[0059] Among them, for example, the aforementioned setting of cutting parameters may include, but are not limited to, parameters such as laser cutting path, laser power, and cutting speed; at the same time, when it is detected that the real-time cutting depth reaches the depth threshold, the power of the cutting laser may be reduced, and the measurement may be continued until the target tissue cutting is completed; specifically, reducing the power of the cutting laser means: adjusting the laser power to the lowest power, and this embodiment also uses laser ranging to determine whether the target tissue cutting is completed, that is, the distance obtained by laser ranging is equal to the maximum cutting depth of the target tissue, then it can be determined that the target tissue cutting is completed; of course, the aforementioned depth threshold is usually less than the maximum cutting depth, and when the real-time cutting depth reaches the depth threshold, it can also be determined that the cutting is completed. The aforementioned two implementation plans can be selected either one, and are not specifically limited here.

[0060] Therefore, through the above design, this embodiment combines OCT technology and laser ranging technology to calculate the real-time cutting depth, and based on this, to control the operation of the laser cutting module; in this way, safe and accurate laser cutting control can be achieved, thereby improving the cutting accuracy and safety. Therefore, it is very suitable for large-scale application and promotion in the field of hard tissue cutting.

[0061] In a possible design, the second aspect of this embodiment provides one of the calculation processes of the real-time cutting depth in the first aspect of the embodiment, as shown below.

[0062] In this embodiment, the data processing module is first used to sort multiple organizational charts in the order of the time interval between the generation time of the organizational chart and the current moment from small to large to obtain a first sorting sequence, and to sort multiple initial cutting depths in the order of the time interval between the measurement time of the initial cutting depth and the current moment from small to large to obtain a second sorting sequence; wherein, this embodiment is equivalent to sorting each organizational chart and each initial cutting depth in the order of the time interval from the current moment from small to large, that is, the organizational chart that is ranked higher, the closer its generation time is to the current moment, and of course, the initial cutting depth that is ranked higher, the closer its measurement time is to the current moment.

[0063] Secondly, this embodiment selects the first several organizational structure diagrams and initial cutting depths from the aforementioned two sorting sequences to calculate the real-time cutting depth. The calculation process is shown below.

[0064] A data processing module is used to filter out the first n tissue structure diagrams from the first sorting sequence and the first n initial cutting depths from the second sorting sequence, and calculate the real-time cutting depth of the target tissue based on the first n tissue structure diagrams and the first n initial cutting depths; wherein, for example, n is an integer greater than 1, and in this embodiment, it is preferably 10, that is, the first 10 tissue structure diagrams and the first 10 initial cutting depths are selected to calculate the real-time cutting depth of the target tissue.

[0065] Furthermore, the data processing module actually performs boundary cutting detection on each of the first n organizational charts to obtain the boundary detection results corresponding to each organizational chart, that is, by identifying the organizational chart, the osteotomy boundary recognition result is obtained, so that the real-time cutting depth of the target tissue can be calculated based on the osteotomy boundary recognition result and the first 10 initial cutting depths.

[0066] In this embodiment, for example, the boundary detection result of any tissue structure diagram is that the cutting point reaches the boundary position between the hard tissue and the soft tissue in the target tissue, or does not reach the boundary position between the hard tissue and the soft tissue in the target tissue; wherein the aforementioned hard tissue may be bone tissue, and the soft tissue is all tissues except bone, as shown in FIG. Figure 6 As shown, Figure 6 The medullary cavity is hard tissue, while the bone cortex is soft tissue, and the boundary area between the two is the boundary position. Figure 6 Whether the cutting measurement point (ie, the cutting point) reaches the boundary area between the two, if so, it reaches the boundary position, otherwise, it does not reach the boundary position.

[0067] Optionally, this embodiment uses a trained boundary cutting detection model to perform boundary cutting detection, wherein the boundary cutting detection model is trained with several historical organizational structure charts as input and the boundary detection results of each historical organizational structure chart as output, and the boundary cutting detection model can be, but is not limited to, a CNN neural network model and a YOLOV3 neural network model. Of course, different image recognition models can be selected for training according to actual needs to obtain the aforementioned trained boundary cutting detection model.

[0068] Specifically, after obtaining the boundary detection results of each tissue structure chart, the data processing module can be used to determine the osteotomy edge recognition constant corresponding to each tissue structure chart based on the boundary detection results of each tissue structure chart. Then, the real-time cutting depth of the target tissue can be calculated based on the aforementioned first n initial cutting depths and all the osteotomy edge recognition constants.

[0069] Furthermore, in this embodiment, for any of the first n tissue structure charts, when the boundary detection result of any of the tissue structure charts is that the cutting point reaches the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to any of the tissue structure charts is 1; when the boundary detection result of any of the tissue structure charts is that the cutting point does not reach the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to any of the tissue structure charts is 0.

[0070] In this way, the data processing module is specifically used to obtain the calibrated bone surface distance of the target tissue (which is obtained through preoperative imaging CT, MR and other information, and then pre-stored in the control system), and from the multiple initial cutting depths, screen out the initial cutting depth corresponding to the tissue structure diagram with an osteotomy edge recognition constant of 1 as the target depth (that is, the last initial cutting depth recorded by the system when the osteotomy edge recognition constant becomes 1); finally, the real-time cutting depth of the target tissue can be calculated based on all osteotomy edge recognition constants, the first n initial cutting depths, the calibrated bone surface distance and the target depth.

[0071] Specifically, the specific calculation formula for the real-time cutting depth is disclosed below, as shown in the following formula (1).

[0072]

[0073] In the above formula (1), d′ represents the real-time cutting depth of the target tissue, d0 represents the distance to the calibrated bone surface, and d i represents the i-th initial cutting depth among the first n initial cutting depths, represents the osteotomy edge identification constant corresponding to the i-th tissue structure chart among the first n tissue structure charts, and D is the target depth. In this embodiment, when there is no tissue structure chart with an osteotomy edge identification constant of 1, the target depth does not exist and is taken as 0.

[0074] In this way, the real-time cutting depth of the target tissue at the current moment can be calculated by the aforementioned formula (1), and then transmitted to the control feedback module. The control feedback module can control the laser cutting module to stop running when it reaches the depth threshold; of course, when it does not reach the depth threshold, it can continue to control the laser cutting module to run according to the set cutting parameters; in this way, accurate laser cutting depth control can be achieved in a closed-loop control manner.

[0075] In one possible design, the third aspect of this embodiment provides the specific structure of the laser cutting module and the laser ranging module in the first aspect of the embodiment.

[0076] First, for example, a laser cutting module may include, but is not limited to: a laser generator, an optical path transmission unit, and a focusing scanning unit; wherein the laser generator is used to generate a cutting laser according to set cutting parameters (i.e., generate a cutting laser with adjustable wavelength and power), such as Er:YAG laser, CO2 laser, femtosecond laser, and other types of lasers that can be used for hard tissue cutting, and then, the cutting laser is transmitted to the focusing scanning unit through the optical path transmission unit, and is converged by the focusing scanning unit to the cutting point on the target tissue to complete the laser cutting of the target tissue; in this embodiment, the laser cutting module also includes a matching optical shutter, a galvanometer, and a robotic arm, etc., that is, the opening of the laser cutting module and the optical shutter is controlled to cut the target tissue.

[0077] Secondly, this embodiment discloses one structure of a laser ranging module:

[0078] In this embodiment, the laser ranging module may include, but is not limited to: a laser, a transmitting telescope, a reflector, a receiving telescope, a filter, a photoelectric element, an amplifying and shaping unit, and a time measurement unit.

[0079] For specific applications, see Figure 3 As shown, the laser is used to transmit a measuring laser to the transmitting telescope at a preset emission frequency, and reflect the emitted measuring laser to the target tissue through a reflector, wherein the reflected laser generated by the target tissue each time is input to the photoelectric element through the reflector, the receiving telescope and the filter, and the photoelectric element converts each input reflected laser into an electrical signal and transmits it to the amplification and shaping unit.

[0080] The amplifying and shaping unit is used to amplify and shape each electrical signal to obtain each processed electrical signal, and transmit each processed electrical signal to the time measurement unit; finally, the time measurement unit can be used to obtain multiple initial cutting depths based on each processed electrical signal; in this embodiment, the amplifying and shaping unit is implemented using an operational amplifier and a filtering circuit, which is a commonly used processing circuit for electrical signals, and its principle will not be repeated here.

[0081] Optionally, the following discloses the working principle of laser ranging:

[0082] In this embodiment, the laser ranging module calculates the distance, that is, the initial cutting depth, by calculating the time difference between the laser emission and reception. When it is working, the laser emits a light pulse to the target tissue, and then the system receives the light pulse reflected by the target, and calculates the distance to the target by measuring the round-trip time of the light pulse. In a specific implementation, the time difference is calculated by determining the number of clock pulses between the emission time and the reception time, and combining the time interval. The schematic diagram can be seen in Figure 2 shown.

[0083] in, Figure 2 Where △T is the time interval, and N is the number of clock pulses counted. Therefore, the product of the two is the time difference between the emission time and the reception time. In this way, the formula: ct / 2 can be used to calculate the initial cutting depth corresponding to each emission of the measuring laser. In the above formula, c represents the speed of light.

[0084] Finally, in this embodiment, the system is further provided with a display module, wherein the display module is electrically connected to the OCT imaging module and the data processing module, and is used to visualize each tissue structure diagram and the real-time cutting depth. In this way, the doctor can observe the cutting progress and depth changes through the real-time display interface provided on the operating table.

[0085] Based on the above description, the following discloses the optical coupling diagram of the control system provided by this embodiment. Figure 4 As shown, Figure 4 C1 and C2 are collimators, A1 and A2 are aspheric lenses with a vertex angle of 2°, L1 and L2 are achromatic lenses, L3 is an achromatic lens pair, OS is an optical shutter, DM1 is a reflector that can reflect 655nm red light and pass >90% of the specific wavelength laser scanned by OCT. Similarly, DM2 is a dichroic mirror that can pass >95% of the specific wavelength laser scanned by OCT according to the specific OCT and cutting laser parameters.

[0086] Thus, through the aforementioned optical coupling schematic diagram and combined with the aforementioned description of the working process of each module, the following discloses the detailed process of the aforementioned control system for laser depth control and decision-making:

[0087] See also Figure 5 As shown, before the system works, the osteotomy path and depth are planned through the control system software based on preoperative imaging CT, MR and other information, and planning and control system instructions are generated. Then, the laser cutting generator (i.e., laser switching module) is controlled to start, and the OCT and laser measurement modules are turned on to scan the cutting area. Then, the real-time cutting speed is calculated using the above method, and it is determined whether the set value (i.e., depth threshold) is obtained; if not, the OS is turned on, and the galvanometer and the robotic arm are controlled to perform hard tissue cutting in the target area according to the plan (i.e., cutting of the target tissue); then, continuous monitoring is performed, and when the real-time cutting depth reaches the set value, the OS is turned off, and the depth is confirmed again; among them, if the real-time cutting depth reaches the set value, the feedback module is controlled to turn off the laser cutting generator; of course, if it does not reach the set value, the cutting continues until it stops when the set value is reached.

[0088] Therefore, through the above detailed explanation of the control system of laser-based hard tissue cutting depth, the present invention combines OCT technology and laser ranging technology to identify the osteotomy boundary of the tissue during the cutting process and calculate the real-time cutting depth. Then, the real-time cutting depth can be used to control the operation of the laser cutting module; in this way, safe and accurate laser cutting control can be achieved, thereby improving the cutting accuracy and safety.

[0089] In one possible design, see Figure 7 As shown, the fourth aspect of this embodiment provides a method for controlling the cutting depth of hard tissue based on laser, wherein the method is executed based on the data processing module in the first to third aspects of the embodiments; wherein the operating steps of the method can be but are not limited to the following steps S1 and S2.

[0090] S1. Acquire multiple tissue structure diagrams and multiple initial cutting depths of the target tissue, wherein the multiple tissue structure diagrams are generated by the OCT imaging module in the control system emitting near-infrared weak coherent light to the target tissue according to a preset emission frequency during the tissue cutting process, and based on the near-infrared reflected light reflected by the target tissue, and the multiple initial cutting depths are measured by the laser ranging module in the control system emitting a measuring laser to the target tissue according to a preset emission frequency during the tissue cutting process.

[0091] S2. Based on multiple tissue structure diagrams and multiple initial cutting depths, the real-time cutting depth of the target tissue is obtained, and the real-time cutting depth is sent to the control feedback module, so that the control feedback module determines whether the real-time cutting depth reaches the depth threshold, and when it is determined that the real-time cutting depth does not reach the depth threshold, the laser cutting module is controlled to operate according to the set cutting parameters until the obtained real-time cutting depth reaches the depth threshold, and the laser cutting module is controlled to stop running.

[0092] The working process, working details and technical effects of the fourth aspect of this embodiment can be found in the first aspect of the embodiment and will not be repeated here.

[0093] The fifth aspect of this embodiment provides an electronic device, comprising: a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the laser-based hard tissue cutting depth control method as described in the fourth aspect of the embodiment.

[0094] For example, the memory may include, but is not limited to, random access memory (RAM), read-only memory (ROM), flash memory, first-in-first-out memory (FIFO), and / or first-in-last-out memory (FILO). Specifically, the processor may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor may be implemented in at least one hardware form selected from the group consisting of a DSP (Digital Signal Processing), an FPGA (Field-Programmable Gate Array), and a PLA (Programmable Logic Array). Furthermore, the processor may include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); and the coprocessor is a low-power processor for processing data in a standby state.

[0095] In some embodiments, the processor may be integrated with a GPU (Graphics Processing Unit, image processor), which is responsible for rendering and drawing the content required to be displayed on the display screen. For example, the processor may be limited to a microprocessor of the STM32F105 series, a reduced instruction set computer (RISC) microprocessor, an X86 architecture processor, or an integrated embedded neural network processor (NPU); the transceiver may be, but is not limited to, a wireless fidelity (WIFI) wireless transceiver, a Bluetooth wireless transceiver, a general packet radio service technology (GPRS) wireless transceiver, a ZigBee protocol (a low-power local area network protocol based on the IEEE 802.15.4 standard, ZigBee) wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver. In addition, the device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0096] The working process, working details and technical effects of the electronic device provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0097] The sixth aspect of this embodiment provides a storage medium storing instructions for the laser-based hard tissue cutting depth control method described in the fourth aspect of the embodiment, that is, the storage medium stores instructions, and when the instructions are run on a computer, the laser-based hard tissue cutting depth control method described in the fourth aspect of the embodiment is executed.

[0098] The storage medium refers to a carrier for storing data, which may include but is not limited to a floppy disk, an optical disk, a hard disk, a flash memory, a USB flash drive and / or a memory stick, and the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0099] The working process, working details and technical effects of the storage medium provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0100] A seventh aspect of this embodiment provides a computer program product comprising instructions, which, when executed on a computer, causes the computer to execute the laser-based hard tissue cutting depth control method as described in the fourth aspect of the embodiment, wherein the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0101] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A laser-based hard tissue cutting depth control system, characterized in that: include: An OCT imaging module, wherein the OCT imaging module is used to emit near-infrared weak coherent light to the target tissue at a preset emission frequency during the tissue cutting process, and receive near-infrared reflected light reflected by the target tissue, so as to generate multiple tissue structure images of the target tissue based on the near-infrared reflected light and send them to the data processing module; A laser ranging module is used to emit a measuring laser to the target tissue according to a preset emission frequency during the tissue cutting process to measure multiple initial cutting depths of the target tissue and send the multiple initial cutting depths to the data processing module; A data processing module is configured to obtain a real-time cutting depth of the target tissue based on a plurality of tissue structure charts and a plurality of initial cutting depths, and send the real-time cutting depth to a control feedback module, wherein obtaining the real-time cutting depth of the target tissue based on the plurality of tissue structure charts and the plurality of initial cutting depths comprises: sorting the plurality of tissue structure charts in ascending order of the time interval between the generation time of the tissue structure charts and the current moment to obtain a first sorting sequence, and sorting the plurality of initial cutting depths in ascending order of the time interval between the measurement time of the initial cutting depths and the current moment to obtain a second sorting sequence, screening out the first n tissue structure charts from the first sorting sequence, and screening out the first n tissue structure charts from the second sorting sequence. the first n initial cutting depths, where n is an integer greater than 1; calculating the real-time cutting depth of the target tissue based on the first n tissue structure diagrams and the first n initial cutting depths; performing boundary cutting detection on each of the first n tissue structure diagrams to obtain a boundary detection result corresponding to each tissue structure diagram; wherein the boundary detection result of any tissue structure diagram is whether the cutting point reaches the boundary position between the hard tissue and the soft tissue in the target tissue, or does not reach the boundary position between the hard tissue and the soft tissue in the target tissue; determining the osteotomy edge recognition constant corresponding to each tissue structure diagram based on the boundary detection results of each tissue structure diagram; and calculating the real-time cutting depth of the target tissue based on the first n initial cutting depths and all the osteotomy edge recognition constants; The control feedback module is used to determine whether the real-time cutting depth reaches the depth threshold, and when it is determined that the real-time cutting depth does not reach the depth threshold, control the laser cutting module to operate according to the set cutting parameters until the obtained real-time cutting depth reaches the depth threshold, and then control the laser cutting module to stop operating.

2. The laser-based hard tissue cutting depth control system according to claim 1, characterized in that: Each of the plurality of organizational charts corresponds to an initial cutting depth; Among them, for any of the first n tissue structure diagrams, when the boundary detection result of any of the tissue structure diagrams is that the cutting point reaches the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to the any of the tissue structure diagrams is 1; when the boundary detection result of any of the tissue structure diagrams is that the cutting point does not reach the boundary position between the hard tissue and the soft tissue, the osteotomy edge recognition constant corresponding to the any of the tissue structure diagrams is 0; a data processing module for obtaining the calibrated bone surface distance of the target tissue and selecting, from the multiple initial cutting depths, an initial cutting depth corresponding to the tissue structure diagram with an osteotomy edge recognition constant of 1 as a target depth; The data processing module is further used to calculate the real-time cutting depth of the target tissue based on all osteotomy edge identification constants, the first n initial cutting depths, the calibrated bone surface distance and the target depth.

3. The laser-based hard tissue cutting depth control system according to claim 2, characterized in that: A data processing module is used to calculate the real-time cutting depth of the target tissue according to the following formula (1); （1） In the above formula (1), Indicates the real-time cutting depth of the target tissue, represents the calibrated bone surface distance, represents the i-th initial cutting depth among the first n initial cutting depths, represents the osteotomy edge identification constant corresponding to the i-th tissue structure diagram in the first n tissue structure diagrams, is the target depth.

4. The laser-based hard tissue cutting depth control system according to claim 1, characterized in that: The laser ranging module includes: a laser, a transmitting telescope, a reflector, a receiving telescope, a filter, a photoelectric element, an amplifying and shaping unit, and a time measurement unit; The laser is configured to transmit a measuring laser to the transmitting telescope at a preset transmission frequency, and reflect each emitted measuring laser to the target tissue via a reflector, wherein each reflected laser generated by the target tissue is input to the photoelectric element via the reflector, the receiving telescope, and the filter, and the photoelectric element converts each input reflected laser into an electrical signal and transmits the signal to the amplification and shaping unit; The amplifying and shaping unit is used to perform amplifying and shaping processing on each electrical signal to obtain each processed electrical signal, and transmit each processed electrical signal to the time measurement unit; The time measurement unit is used to obtain multiple initial cutting depths based on the processed electrical signals.

5. The laser-based hard tissue cutting depth control system according to claim 1, characterized in that: The laser cutting module includes: a laser generator, an optical path transmission unit and a focusing scanning unit; The laser generator is used to emit cutting laser to the optical path transmission unit according to the set cutting parameters, wherein the cutting laser is transmitted to the focusing scanning unit through the optical path transmission unit and is focused to the cutting point on the target tissue by the focusing scanning unit.

6. The laser-based hard tissue cutting depth control system according to claim 1, characterized in that: The emission light path of the near-infrared weak coherent light of the OCT imaging module is on the same straight line as the emission light path of the cutting laser of the laser cutting module.

7. The laser-based hard tissue cutting depth control system according to claim 1, characterized in that: Also includes: A display module, wherein the display module is electrically connected to the OCT imaging module and the data processing module, and is used to visually display each tissue structure diagram and the real-time cutting depth.

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