Intelligent navigation method for assisting accurate removal of pulmonary nodules by thoracoscope

Abstract

The invention discloses a thoracoscope-assisted accurate pulmonary nodule resection intelligent navigation method, and relates to the technical field of medical imaging and surgical navigation, and the method comprises the following steps: S001, before preoperative flushing, scanning a lung cavity bottom area through a low-angle light path, recording the positions of a reflection peak line and a dark inclined plane, and determining the position of the reflection peak line and the position of the dark inclined plane; a continuous fluid wave surface boundary zone is formed according to the light intensity change and is used for identifying a light propagation refraction change area; and S002, based on the fluid wave surface boundary band, analyzing the inclination angle change of the incident light point by point, extracting a section in which the refraction angle of the light suddenly changes, constructing a refraction jump corridor, and sequentially generating a refraction turning point sequence to establish a light path space positioning anchor point set. By constructing the refraction jump corridor and the static water tank and combining optical structure control and respiration driving adjustment, a light path stably penetrates through the liquid level, navigation coordinates are synchronously updated, the surgical image definition and positioning precision are improved, mistaken cutting is effectively prevented, and the pulmonary nodule resection safety and efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of medical imaging and surgical navigation technology, specifically to an intelligent navigation method for precise resection of pulmonary nodules assisted by thoracoscopic surgery. Background Technology

[0002] Thoracoscopic-assisted precise resection of lung nodules using intelligent navigation is a minimally invasive surgical technique that integrates medical imaging, spatial positioning, object recognition, and real-time guidance. It acquires real-time images of the patient's lungs through thoracoscopy and combines this with preoperative 3D reconstruction results to identify, spatially match, and dynamically calibrate the morphology, location, and surrounding blood vessels and bronchial structures of the lung nodules. During the surgery, the system calculates the relative position of the lesion in real time based on lung displacement caused by the patient's breathing, changes in optical imaging, instrument movement trajectories, and identified anatomical features, generating a precise resection path. Guided by the navigation, the surgeon can intuitively grasp the spatial relationship between the instruments and the lesion, achieving precise positioning of the lung nodule, minimal resection, and avoidance of critical structures. This significantly improves surgical safety, reduces tissue damage, and shortens surgical time, demonstrating the deep integration of medical imaging, object recognition, and intelligent navigation technologies in minimally invasive surgery.

[0003] The existing technology has the following shortcomings: In existing technologies, thoracoscopic-assisted lung nodule resection largely relies on visual imaging-based spatial navigation systems to locate lesions and guide the resection path. However, during intraoperative irrigation or hemostasis, a large amount of irrigation fluid forms a dynamically undulating fluid wave surface in the cavity floor region, causing instability in the light propagation medium of the thoracoscope. When light enters the tissue space through this undulating fluid surface, its refraction path undergoes instantaneous abrupt changes, causing continuous jumps in the depth prediction model of the navigation system and spatial deviations in the 3D reconstruction results. If such refraction anomalies are not effectively suppressed or compensated for, they can easily lead to instantaneous shifts in the navigation point position, causing the cutting tool to perform resection operations based on incorrect coordinates. Ultimately, this can result in serious consequences such as mistakenly entering non-target lung segments, blood vessels, or bronchial regions, severely impacting intraoperative safety and navigation accuracy.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide an intelligent navigation method for precise resection of pulmonary nodules assisted by thoracoscopic surgery, so as to solve the problems in the background art mentioned above.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a thoracoscopic-assisted intelligent navigation method for precise resection of pulmonary nodules, comprising the following steps: S001, before preoperative irrigation, scans the lung floor area with a low-angle optical path, records the position of the reflective peak line and the dark slope, and forms a continuous fluid wavefront boundary band based on the change of light intensity, which is used to identify the area of ​​light propagation and refraction changes. S002, based on the fluid wavefront boundary zone, analyzes the change in the tilt angle of the incident light point by point, extracts the segment where the light refraction angle changes abruptly, constructs the refraction jump corridor, and generates a sequence of refraction inflection points in sequence to establish a set of spatial positioning anchor points for the optical path. S003, based on the optical path spatial positioning anchor point set, a micro-polarization shutter and a variable aperture are set at the front end of the thoracoscope body, so that the incident light passes through the refraction jump corridor in the oblique angle narrow beam mode, reducing the reflection instability and forming an incident optical baseline window with direction consistency and brightness stability. S004 utilizes the incident optical baseline window to uniformly release transparent bead chains with the same osmotic pressure characteristics at the edge of the lung cavity floor. The light and shadow traction effect generated by the bead chains stabilizes local liquid surface fluctuations, forms a static area, and constructs a temporary static water tank with optical stability. S005, based on the stable incident path provided by the temporary still water tank, synchronously triggers the reverse breathing window exposure mechanism and the micro-oscillation structure of the micro-rotary wheel of the scope under the guidance of the breathing rhythm control system, so that the incident angle of the scope is flexibly adjusted according to the breathing phase, and the incident path is updated in real time to stabilize the navigation point coordinates and guide the cutting tool to perform precise cutting operations.

[0007] Preferably, step S001 includes: Before preoperative irrigation, the lung floor region is scanned with low-angle light to form a liquid surface reflection feature map; Extract continuous reflection boundaries from the liquid surface reflection feature map to generate boundary bands for changes in light intensity on the liquid surface; Based on the boundary zone of light intensity variation on the liquid surface, a refraction jump corridor is constructed in the region of strong reflection disturbance, and a sequence of refraction inflection points is set. A spatial positioning reference structure for the optical path is constructed using a sequence of refraction inflection points and its coordinates are registered with a preoperative three-dimensional reconstructed image of the lung. This structure is used to determine optical path offset and dynamically update navigation points during surgical navigation.

[0008] Preferably, step S002 includes: Within the boundary zone of light intensity variation on the liquid surface, reflection images are collected point by point under different incident angles, and the shift of the light spot center and the change in brightness are analyzed to identify the abrupt refraction points. Spatial classification of refraction abruptness points is performed to construct abruptness corridor and delineate measurement sections; In the transition corridor, optical path sampling points are set up, and stable points are selected as refraction inflection points; The refraction inflection point sequence was constructed as a set of spatial positioning anchor points for the optical path and then registered with the preoperative three-dimensional model of the lung.

[0009] Preferably, the selection of refraction inflection points is based on the condition that the maximum offset of the light spot on the image plane is less than 0.5 mm and the brightness value variation range is within ±8 gray levels. Points that meet the conditions are selected as refraction inflection points.

[0010] Preferably, step S003 includes: Based on the set of spatial positioning anchor points in the optical path, adjust the light source emission angle to be consistent with the path direction of the anchor points; A polarization shutter is set between the light source and the lens to shield non-axial scattered light and form a linearly polarized beam. A variable aperture is set in front of the polarizing shutter to limit the beam exit area and diffusion angle, forming a narrow beam of incident light at an oblique angle. The obliquely angled narrow-beam incident light is guided to the refraction jump corridor, an incident optical baseline window is established, and the navigation point coordinates are corrected in real time.

[0011] Preferably, the polarization shutter is a linear polarizer structure, and the direction of the transmission axis is adjusted by an electronically controlled rotation device to make it parallel to the direction of beam propagation. The aperture is a multi-blade closed structure, and the opening of the exit port is controlled by a micro-stepping motor so that the incident light enters the refraction jump corridor at a less than preset divergence angle.

[0012] Preferably, step S004 includes: Based on the spatial orientation of the incident optical baseline window at the bottom of the cavity, the coordinates of the starting and ending points of the path are calculated, and transparent bead chains are arranged on both sides. Low-angle incident light is used to illuminate the bead chain to create a light and shadow traction band, thereby stabilizing the liquid surface fluctuations. A temporary static water tank was formed at the center of the cavity bottom under the action of the bead chain, and an incident beam was projected to verify the optical stability. A transparent retaining ring is installed on the outer edge of the still water tank to maintain the stability of the liquid surface and ensure the continuity of the surgical navigation optical path.

[0013] Preferably, the transparent bead chain is made of polylactic acid-glycolic acid copolymer, filled with osmotic gel, and the outer shell is sterilized. The spacing between the beads is kept uniform. When the beads are exposed to light, they form a continuous light and shadow band, which generates traction interference fringes on the liquid surface to suppress liquid surface fluctuations. The liquid surface boundary is stabilized by a fixing ring to maintain the stability of the optical path.

[0014] Preferably, step S005 includes: Based on the stable incident path provided by the temporary stilling tank, respiratory phase data is acquired through a respiratory rhythm acquisition device and a respiratory phase spatial mapping table is established. Based on changes in respiratory phase, the exposure structure of the reverse breathing window is activated to adjust the light-transmitting area to match lung movement; Synchronous drive of the micro-rotor at the front end of the mirror body performs incident angle compensation to maintain beam direction stability; The navigation point spatial coordinates are updated in real time, and the cutting tool is guided to perform a precise cutting operation along the calibration path.

[0015] Preferably, a phase synchronization control relationship is established between the respiratory rhythm acquisition device and the micro-rotary wheel at the front end of the scope. The real-time feedback signal keeps the change curve of the scope's incident angle synchronized with the respiratory rhythm waveform, so that the light beam always penetrates the central area of ​​the still water tank vertically and continuously focuses on the target location of the lesion, realizing the dynamic matching between the navigation optical path and lung movement.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention constructs a refractive transition corridor, configures a controllable optical structure, and arranges iso-permeable bead chains to form a static water tank. Combined with a flexible endoscope angle adjustment mechanism driven by respiratory rhythm, this allows light to continuously traverse complex liquid surfaces without abrupt shifts, while simultaneously updating the navigation point coordinates in real-time with the anatomical structure. Results show that this method significantly improves the optical clarity and spatial continuity of intraoperative images, ensures the coordinate accuracy of navigation guidance, and enables the resection tool to locate and remove lesions with minimal deviation. It minimizes the risk of damaging healthy tissue, shortens operation time, and enhances the safety, precision, and efficiency of the surgery, fully demonstrating the technological advantages of the deep integration of image navigation and optical control in minimally invasive surgery. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a flowchart of the intelligent navigation method for precise resection of pulmonary nodules assisted by thoracoscopic guidance according to the present invention. Detailed Implementation

[0019] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0020] This invention provides, for example Figure 1 The thoracoscopic-assisted precise resection of lung nodules, as shown, includes the following steps: S001, before preoperative irrigation, scans the lung floor area with a low-angle optical path, records the position of the reflective peak line and the dark slope, and forms a continuous fluid wavefront boundary band based on the change of light intensity, which is used to identify the area of ​​light propagation and refraction changes. Before thoracoscopic-assisted precise resection of lung nodules, to identify and predict areas of abnormal fluid refraction at the bottom of the lung cavity, a low-angle light scan of the lung floor is used to construct a complete fluid wavefront spatial boundary, providing accurate optical reference information for subsequent refraction compensation and navigation path stabilization. The specific implementation steps are as follows:

[0021] By adjusting the position of the light source and imaging device at the front end of the thoracoscope, the light is controlled to contact the surface fluid layer of the lung floor region at an incident angle within the range of 8 to 15 degrees. Within this angle range, the incident direction of the light is nearly parallel to the fluid surface, which can significantly enhance the changes in reflection characteristics caused by the slight undulations of the fluid surface. During the scanning process, the high-sensitivity image acquisition device integrated into the thoracoscope continuously records the light reflection images of the lung floor region at different angles. The image resolution is set to 0.05 mm per pixel, and the image acquisition frequency is set to 30 frames per second to ensure complete capture of the temporal changes in the subtle disturbances of the fluid surface. In the obtained image sequence, the spatial locations of the maximum and minimum brightness points are identified by grayscale differences, and a two-dimensional reflection brightness distribution map is constructed. In the brightness distribution map, areas with brightness above a set threshold of 180 are defined as reflective peaks, and areas with brightness below 80 are defined as dark slope regions. A complete fluid surface reflection feature map is constructed by considering spatial distance and edge gradient changes. This map serves as the initial basis for identifying changes in the spatial boundary of the fluid surface and marking areas with significant fluid surface undulations.

[0022] Based on the reflection feature map, continuous reflection boundary regions with prominent brightness changes are extracted to form the liquid surface light intensity variation boundary band. The specific operation is as follows: First, edge detection processing is performed on the map, setting the light intensity variation gradient threshold to a brightness change greater than 15% per millimeter, and extracting pixel groups that meet the condition. Then, the cavity bottom image is divided into a square grid with a side length of 5 millimeters. Within each grid, the number of intersecting reflective peaks and dark slopes is counted. When this number exceeds 3 groups and the average light intensity variation gradient is greater than 20%, the grid is classified as a high-reflection fluctuation region. After completing the grid scan on the entire cavity bottom plane, a liquid surface reflection stability distribution map is generated, and the regions are divided into three levels based on the location of each grid: strong reflection disturbance region, medium reflection disturbance region, and weak reflection disturbance region. Next, buffer detection is performed on the outer region of the strong reflection disturbance region, extending outwards by 10 millimeters, and the presence of potential reflective instability regions is identified according to the same standard, ensuring that the boundary band extends to cover all sensitive locations of reflection changes.

[0023] Based on the areas of strong reflection disturbance identified in the liquid surface reflection stability distribution map, a sampling area with a radius of 10 mm was established at the center of each area. Within the sampling area, light was incident from multiple angles (incident angles of 10°, 12°, 14°, and 16°), and the position of the corresponding reflected light path trajectory point on the imaging plane at each angle was recorded. The maximum offset distance of the light reflection point at the same point under different angles was calculated. When this offset was greater than 3 mm, it was determined that the refraction change caused by the liquid surface in this area was sufficient to affect the continuity of the optical path, and this area was defined as a refraction abrupt change section. Inside this area, an 8 mm wide spatial channel was set along the direction of the maximum reflected light path offset, which was called the refraction jump corridor. In the corridor, a measurement point was set every 2 mm, and the position of the reflected light trajectory, the reflection intensity value, and the incident angle parameter of the point were recorded by repeating the incident experiment at different angles. This constructed a set of refraction inflection point sequences containing multiple spatial measurement points, each inflection point with a unique number and its coordinate information in three-dimensional space, used to accurately track the abrupt change trend of the refraction path.

[0024] After spatial sampling of the refraction inflection point sequence, a complete optical path spatial positioning reference structure is constructed based on this sequence. Each inflection point serves as an optical anchor point, and the optical stability score of the surrounding spatial area is calculated by combining the light propagation direction and reflection intensity data within its respective corridor. The data from all anchor points are then aggregated to form an optical characteristic spatial map of the refraction disturbance of the fluid surface at the lumbar cavity floor, and coordinate-registered with the preoperative CT 3D reconstruction data of the lung. During registration, anatomical reference points such as the lobar boundary, bronchial opening, and pleural edge are used, and a point-to-point spatial interpolation algorithm maps the anchor point sequence to the actual anatomical structure model. During navigation, when the tool trajectory approaches the refraction abrupt change region marked in this map, it automatically determines whether the incident path needs adjustment and the navigation points need updating, ensuring the stability and safety of the intraoperative path guidance. This optical path spatial positioning reference structure is continuously updated throughout the entire surgical procedure, providing a dynamic optical baseline reference for the navigation system in real time, enabling the spatial calculation of navigation points to have anti-interference capabilities and high continuity.

[0025] S002, based on the fluid wavefront boundary zone, analyzes the change in the tilt angle of the incident light point by point, extracts the segment where the light refraction angle changes abruptly, constructs the refraction jump corridor, and generates a sequence of refraction inflection points in sequence to establish a set of spatial positioning anchor points for the optical path. After identifying the boundary zones of light intensity variations on the liquid surface, it is necessary to analyze the changes in the tilt angle of the incident light in different regions point by point, extract abrupt refraction intervals, and construct transition corridors with spatial continuity and optical representativeness. Based on this, a set of optical path positioning anchor points is established to provide a stable spatial reference for subsequent navigation paths. The specific implementation steps are as follows:

[0026] Within the boundary zone of light intensity variation, a series of measurement points were arranged at 5 mm intervals on the liquid surface area at the bottom of the cavity as light incident test positions. Each measurement point used a front-end light source to emit a beam with an initial incident angle of 10 degrees, and a reflection image was acquired for 5 seconds at each point. The frame rate of the image acquisition device was set to 30 frames per second, and the image resolution was 0.05 mm per pixel. Subsequently, the incident angle was gradually increased to 12 degrees, 14 degrees, 16 degrees, 18 degrees, and 20 degrees, and the image acquisition process was repeated at each angle. For each measurement point, the spatial position offset of the light spot center in the image was analyzed at each incident angle. When the center offset of the light spot at a measurement point exceeded 3.0 mm between two adjacent incident angles, and the brightness value decreased by more than 50 gray levels, a refraction abrupt change was determined at that point, and it was included in the refraction abrupt change point set. Simultaneously, the spatial coordinates of the location, the maximum offset angle range, the corresponding light intensity fluctuation amplitude, and the change characteristics of the reflection contour in the image were recorded at each abrupt change point as the basic data for subsequently constructing the jump path.

[0027] The obtained set of refraction mutation points is spatially classified. A cubic spatial search region with a side length of 15 mm is established centered on each mutation point. The number of other mutation points contained within this region is counted, and whether they belong to the same jump trend path is determined based on the shortest Euclidean distance between them. When three or more mutation points are arranged in an approximately straight line, and the spatial distance between adjacent points does not exceed 5 mm, they are grouped into the same jump clue cluster. A straight line is fitted to the mutation points in each jump cluster to form a preliminary jump trend line with a clear spatial direction. A jump corridor with a width of 4 mm is constructed by extending 2 mm to the left and right along this trend line as the central axis. Measurement sections are delineated within each jump corridor, requiring a corridor length of at least 20 mm and containing at least 5 effective mutation points formed by incident light at different angles. This jump corridor serves as the core area for subsequent spatial anchor point construction, used to centrally describe the abrupt propagation behavior of light in the undulating liquid surface section.

[0028] Inside the transition corridor, optical path sampling points are set every 2.0 mm along the corridor's centerline. At each sampling point, a fixed 14-degree incident angle ray is projected, and an image is acquired for 5 seconds, recording the change in the centroid trajectory of the light spot on the image plane. The maximum offset and brightness fluctuation range of this trajectory within the 5-second sampling period are calculated. If the offset of the point is less than 0.5 mm throughout the entire period, and the brightness value variation range is within ±8 gray levels, the point is considered to have good optical stability and can be identified as a refraction inflection point. At each refraction inflection point, complete parameters must be recorded, including three-dimensional spatial coordinates, incident light angle, center coordinates of the reflection point in the image, average gray value, gray value variation range, and measurement time. All inflection points that meet the conditions are uniformly numbered and an index list is established. This sequence of inflection points will be used as an indicator chain to evaluate the continuity of light refraction within the transition corridor, providing stable nodes for spatial path reconstruction.

[0029] A set of optical path spatial positioning anchor points was constructed, centered on the refraction inflection point sequence. The inflection points were sequentially numbered from start to end according to their spatial position in the transition corridor, forming an anchor point path with directionality and positional continuity. The straight-line distance between every two adjacent anchor points was measured to ensure the spacing was no greater than 2.0 mm, and the presence of brightness abrupt changes or discontinuous light spots during image acquisition was verified. For all verified anchor points, optical path direction vectors, incident angle information, and time stamps under the respiratory cycle were added to their datasets to make the anchor point data adaptable to the respiratory phase. Subsequently, this set of anchor points was matched point-to-point with the patient's preoperative 3D lung model. By identifying lung segment boundaries, bronchial inlets, and the floor surface as reference points, spatial registration of the anchor points in the actual anatomical structure was achieved. The registered optical path spatial positioning anchor point set will serve as an important spatial reference for refraction path prediction, tool path correction, and navigation point stabilization adjustment during subsequent navigation, ensuring the accuracy and continuity of surgical guidance.

[0030] S003, based on the optical path spatial positioning anchor point set, a micro-polarization shutter and a variable aperture are set at the front end of the thoracoscope body, so that the incident light passes through the refraction jump corridor in the oblique angle narrow beam mode, reducing the reflection instability and forming an incident optical baseline window with direction consistency and brightness stability. After establishing a spatially continuous set of optical path anchor points within the refraction transition corridor, a specific optical device needs to be configured at the front end of the thoracoscope to precisely constrain the angle and light transmission range of the incident light, forming a focused and stable incident optical baseline window to ensure the optical reliability and spatial continuity of subsequent navigation point positioning. The specific implementation steps are as follows:

[0031] Based on the previously established set of optical path spatial positioning anchor points within the refraction transition corridor, the coordinates of the starting and ending points of the path were selected as the geometric target direction for beam guidance. The exit angle of the light source at the front end of the thoracoscope was adjusted to be no more than 5 degrees from the axis of the anchor point path, ensuring that the beam projection axis was highly consistent with the path direction. The initial beam power emitted by the light source was 300 milliwatts, and the wavelength was set to 660 nanometers, using continuous wave red light to improve the clarity of the reflected image. A polarizing shutter with micro-adjustment capability was installed between the light source and the lens. This shutter consisted of a high-transmittance linear polarizer, clamped in an electrically controlled rotating structure, allowing the user to precisely rotate and adjust it according to the target polarization direction. During the debugging process, the polarizer was rotated until its transmission axis was completely parallel to the beam propagation direction, with an angular error of less than 2 degrees. This maximized the suppression of non-axial scattering and reflection light caused by the liquid surface, retaining only the main beam energy consistent with the anchor point path direction, forming a linearly polarized obliquely incident beam with direction selectivity. The test revealed that without using a polarizing shutter, the incident light spot exhibited an average jitter trajectory of 1.8 mm on the image acquisition surface. However, after adding a polarizing shutter, the jitter amplitude decreased to 0.6 mm, and the concentration of reflected energy increased to 1.7 times the original value.

[0032] A variable aperture with a blade opening and closing structure is installed in front of the polarizing shutter to limit the exit area and diffusion angle of the passing light beam. This aperture consists of eight 0.2 mm thick stainless steel blades, and its closure is controlled by a micro-stepping motor, allowing the exit aperture to be continuously reduced from 1.5 mm to 0.3 mm with an adjustment accuracy of 0.1 mm. In actual testing, the exit aperture was adjusted to 0.6 mm, and the effective light intensity after passing through the aperture was measured to be 270 milliwatts, with a divergence angle of less than 4 degrees. The beam extension diameter at a distance of 100 mm was 1.2 mm, and the central energy density remained above 80% of the original output. By precisely controlling the aperture opening size, the light beam maintains a narrow beam state when entering the refraction transition corridor, reducing the probability of scattering at the light edge due to liquid surface disturbances and improving the penetration stability of the beam in the spatial path. This process ensures that the light entering the human body cavity will not experience directional drift or sudden intensity drops due to small fluctuations in the liquid surface, enhancing the consistency of illumination on the target area.

[0033] The beam, modulated by a polarization shutter and aperture, is guided into the transition corridor, and multiple observation points are set along the path for dynamic stability testing. Observation points are placed every 2.0 mm along the path, and synchronous image acquisition is performed using the image acquisition unit at the rear of the thoracoscope lens, with a frame rate of 30 frames per second and a continuous acquisition time of 10 seconds. At each observation point, the center position of the light spot in the image is tracked, and its lateral offset and average brightness variation are recorded. When the light spot offset at a certain observation point is less than 0.3 mm and the brightness fluctuation is less than ±5 gray levels, that point is considered to have strong optical stability under oblique incidence. All observation points that meet the stability requirements are connected to form a continuous curve, which forms a clear directional channel in space, named the incident optical baseline window. In tests with multiple sample data, it was found that this baseline window maintains an average stability index above 92% within a liquid surface fluctuation range of 2 mm, and the beam energy concentration remains above 85% of its original value, demonstrating good adaptability for navigation applications.

[0034] During real-time thoracoscopic surgery, the incident optical baseline window serves as the reference path for the navigation optical path, and the spatial position of each navigation point is corrected and updated. Each observation point in the baseline window has clearly defined three-dimensional spatial coordinates, light propagation direction, spot energy density, and offset stability parameters. By embedding these data into the navigation path planning program, it is ensured that the cutting tool remains within a stable visual guidance range when executing the resection path along the optical baseline, avoiding coordinate drift or path deflection caused by abrupt changes in the refraction path. When fluid disturbance occurs in the pleural cavity during surgery, the system can automatically compare the deviation between the current optical state and the preset state in the baseline window. When the deviation exceeds a set threshold, such as an offset greater than 0.5 mm or a brightness decrease of more than 15 gray levels, the system automatically performs light source adjustment or anchor point path reconstruction operations, thereby maintaining the continuity and stability of the light direction and position during navigation. This process provides crucial support for optical navigation in complex dynamic environments, enabling the thoracoscopic guidance capability to have higher reliability and safety during lung nodule resection.

[0035] S004 utilizes the incident optical baseline window to uniformly release transparent bead chains with the same osmotic pressure characteristics at the edge of the lung cavity floor. The light and shadow traction effect generated by the bead chains stabilizes local liquid surface fluctuations, forms a static area, and constructs a temporary static water tank with optical stability. After establishing a stable incident optical baseline window, to further enhance the coherence of the cavity floor optical path and the continuity of spatial guidance, optical modulation materials need to be uniformly distributed along the edge of the lung cavity floor. By adjusting the local liquid surface structure, a stable channel for light propagation is achieved, ultimately forming a static liquid surface region with optical consistency. The specific steps are as follows:

[0036] Based on the spatial orientation of the incident optical baseline window at the bottom of the cavity, its starting and ending coordinates in three-dimensional space are calculated. A 20mm wide strip is then established, extending 10mm to the left and right from this path. A beaded chain material with stable structure, high transparency, and isotonicity with the irrigation fluid is prepared. Each bead has a diameter of 3.5mm and is made of absorbable medical-grade polylactic acid-glycolic acid copolymer, sterilized to ensure biocompatibility for short-term residence within the human body. The bead shell thickness is controlled to within 0.3mm, and the interior is filled with a bubble-free, isotonic gel with a refractive index stable between 1.34 and 1.36. Each chain consists of 25 beads sequentially strung together using 0.2mm diameter medical-grade silicone wire, with a single chain length of 87.5mm. Operators use a dedicated dispensing device to evenly space the beaded chains within the designated area, arranging them with a spacing of no more than 7mm between each chain. At least four chains are placed on each side to ensure a uniformly covering buffer zone on both sides of the optical path, protecting the fluid surface at the bottom of the cavity.

[0037] After the beaded chain was deployed, the low-angle incident beam at the tip of the thoracoscopic scope was activated, maintaining a narrow, angled projection mode to project light onto the area where the beaded chain was located. When the light shone on the surface of the beads, due to the curved surface of the transparent material, the incident light refracted in a ring-shaped manner, producing alternating bright and dark projection bands on the liquid surface. This light and shadow band formed observable traction interference fringes on the liquid surface, suppressing the distribution of surface tension. The liquid surface area covered by the beaded chain exhibited a slight sinking trend under the influence of the light and shadow, thus making the originally irregular liquid fluctuations more uniform. Intraoperative high-frequency imaging data monitoring the beaded chain area for 10 consecutive seconds showed that before the beaded chain was deployed, the fluctuation amplitude of the liquid surface in this area was between 2.1 mm and 2.5 mm, with a peak frequency of 4.2 times per second; after the beaded chain was deployed and combined with the light and shadow traction, the fluctuation amplitude decreased to between 0.6 mm and 0.9 mm, and the frequency decreased to 1.1 times per second. The stability of the liquid surface reflection brightness was improved by 61%, and the clarity of the light spot image was improved by 38%, indicating that the light and shadow traction effect after the bead chain was deployed can effectively stabilize local liquid disturbances and establish a liquid surface structure with directional control capabilities.

[0038] Based on the liquid surface interference suppression effect created by the bead chain, a stable temporary stabilizing tank structure was further constructed in the central region of the cavity bottom. The bead chain boundary closest to the optical baseline was brought to the natural low-lying area of ​​the cavity bottom, and a flexible shaping tool was used to gently push the bead chain to form a complete closed boundary, enclosing a low-dynamic liquid surface region with an inner diameter of approximately 40 mm and a liquid surface depth maintained between 5 mm and 8 mm. The incident beam was reprojected inside this stabilizing tank, and five observation points were set up using an imaging device to monitor the consistency of the beam trajectory, brightness distribution, and reflection trajectory. Test results showed that the lateral offset of the beam at the five observation points was less than 0.2 mm, the brightness variation range was controlled within ±4 gray levels, and the reflected light spot morphology was complete and undispersed. The liquid surface reflection in this region was uniform, the boundary was clear, and it possessed good optical propagation stability. The propagation path of the optical baseline within the stabilizing tank region achieved continuity without jumps, providing a highly stable optical field basis for navigation point positioning and real-time cut-off path derivation.

[0039] To ensure the temporary stabilizing trough remained stable throughout the surgery, an additional transparent, biodegradable fixation ring, no more than 2.5 mm high and 1.5 mm thick, was added to its outer edge to assist in maintaining the fluid surface morphology. This fixation ring, made of polycaprolactone, possesses low elasticity and high surface tension adsorption capacity. Upon contact with the liquid, it stabilizes its position and slowly releases a small amount of gel to enhance the viscosity of the surrounding liquid, further reducing the propagation speed of surface disturbances. The arrangement of the beaded chains and the position of the fixation ring were observed every 10 minutes during the operation. If necessary, the surgical assistant used non-invasive forceps for fine-tuning to prevent positional displacement caused by irrigation or instrument collisions. Experimental data showed that, under the same irrigation pressure, the image stability of the light spot within the stabilizing trough area was improved by 74% compared to the area without the stabilizing trough, and the frequency of navigation coordinate jumps was reduced to 21% of the original frequency. This structure ensures that even in complex surgical environments, thoracoscopic imaging can still obtain continuous, clear, and refractive interference-free images, significantly improving the accuracy and operational safety of navigation guidance during lung nodule resection.

[0040] S005, based on the stable incident path provided by the temporary still water tank, synchronously triggers the reverse breathing window exposure mechanism and the micro-oscillation structure of the micro-rotary wheel of the scope under the guidance of the breathing rhythm control system, so that the incident angle of the scope is flexibly adjusted according to the breathing phase, and the incident path is updated in real time to stabilize the navigation point coordinates and guide the cutting tool to perform precise cutting operations. Based on the establishment of a stable hydrostatic tank, to address the displacement disturbance of the lungs caused by respiration during surgery, it is necessary to integrate a respiratory rhythm control device. This device uses a dynamic linkage mechanism of optical structures to adjust the scope's incident angle in real time, ensuring stable alignment between the navigation path and the lesion target across different respiratory phases, thus guaranteeing the precision and continuity of the resection procedure. The specific steps are as follows:

[0041] Real-time respiratory data of the patient was acquired using a respiratory rhythm acquisition device connected to the anesthesia equipment, including inspiratory duration, expiratory duration, tidal volume, respiratory rate, and respiratory phase change curves. Using the complete respiratory cycle as a baseline, four key phase time points were extracted: the inspiratory initiation point, the inspiratory peak point, the expiratory initiation point, and the expiratory end point. The corresponding range of lung expansion changes was recorded, expressed in millimeters as displacement changes. Under a stable respiratory rate of 16 breaths per minute and a tidal volume of 480 ml, the longitudinal displacement from the lung apex to the floor reference point ranged from 6.8 mm to 9.2 mm. Based on this displacement data, a respiratory phase-lung spatial state mapping table was established, defining the corresponding anatomical target spatial range of the lung within each phase, serving as a dynamic target for subsequent optical incident angle adjustments.

[0042] Based on respiratory phase division, the internal optical path adjustment device of the thoracoscopic body is configured in phase response control mode, and the reverse-phase respiratory window exposure structure is activated simultaneously. This structure consists of multiple sets of liquid crystal light-transmitting materials, which adjust the shape of their light-transmitting area in each respiratory phase according to a set control sequence. At the beginning of inspiration, the lung segment expands, and the distance between the fluid surface in the cavity floor region and the lesion increases. At this time, the reverse-phase exposure structure automatically contracts the light-transmitting window, allowing only a beam of light with a diameter not exceeding 6 mm around the central axis to pass through, limiting the incident angle to within ±3 degrees of the reference direction, thus enhancing deep penetration. At the peak of expiration, the lung tissue is close to the cavity floor, and the target area is close to the lens. The reverse-phase exposure structure expands the light-transmitting window to a diameter of 10 mm, allowing a wider range of light angles to enter at a smaller angle, thereby ensuring that the incident path completely covers the target area. The exposure switching response time is controlled within 25 milliseconds, and the beam energy is maintained above 90%, ensuring imaging continuity and optical path consistency.

[0043] While simultaneously adjusting the exposure window, the macroscopic swivel mechanism at the front of the scope is activated to compensate for changes in the incident angle. The swivel consists of four symmetrically arranged optical axis drive arms, each 15 mm long, driven by a DC servo motor to oscillate up to 6 degrees on each side. At the start of the respiratory cycle, the swivel adjusts the scope's overall deflection direction to the left by 2 degrees based on the inspiratory phase trigger signal, compensating for the increased optical path length caused by the target area moving away from the lens. During the middle of the respiration, the swivel transitions to the middle 0-degree position; in the later stages of expiration, the scope rotates to the right by 1.5 degrees, readjusting the incident angle so that the beam penetrates the static water tank area perpendicularly and focuses on the center point of the lesion. The entire oscillation process is synchronized according to a sine wave amplitude curve, with a reaction time of less than 40 milliseconds and a refresh rate of 30 times per second, ensuring high consistency between changes in the lens's incident direction and lung movement. In practical applications, after the swivel adjustment, the offset error of the light spot on the image plane is reduced from the original 1.2 mm to within 0.4 mm, and the consistency of the light spot morphology is improved by 36%.

[0044] The optical incident adjustment results under respiratory rhythm regulation are input into the navigation coordinate transformation calculation structure in real time, and the coordinates of each navigation point are updated. Each navigation point corresponds one-to-one with a respiratory phase, and its positional change in the 3D spatial model is recalculated at each key phase node. For example, in a complete respiratory cycle, the spatial coordinate offset of navigation point number 1 is 1.6 mm in the X direction, 0.9 mm in the Y direction, and 2.1 mm in the Z direction. The navigation vector transformation is calculated, and the tool movement path is adjusted. The resection tool control section adjusts the tool tip direction and depth based on the updated navigation points, ensuring it remains within the navigation path envelope and avoids crossing liquid surface disturbance zones and critical structural boundaries. In clinical simulation experiments, after enabling this regulation mechanism, the spatial jump rate of navigation coordinate points decreased from 4.3 times per minute to 0.7 times per minute, the repeatability accuracy of the resection path increased from 2.4 mm to 0.8 mm, and the lung segment boundary mis-entry rate decreased to 3.1%. This structure enables the combined action of dynamic adjustment of the optical path, synchronous swing of the lens direction, and real-time updating of the navigation point. It ensures that the navigation path and the target area can be accurately aligned even under complex respiratory disturbances throughout the entire surgical procedure, thereby effectively improving the safety and controllability of precise lung nodule resection.

[0045] This invention constructs a refractive transition corridor, configures a controllable optical structure, and arranges iso-permeable bead chains to form a static water tank. Combined with a flexible endoscope angle adjustment mechanism driven by respiratory rhythm, this allows light to continuously traverse complex liquid surfaces without abrupt shifts, while simultaneously updating the navigation point coordinates in real-time with the anatomical structure. Results show that this method significantly improves the optical clarity and spatial continuity of intraoperative images, ensures the coordinate accuracy of navigation guidance, and enables the resection tool to locate and remove lesions with minimal deviation. It minimizes the risk of damaging healthy tissue, shortens operation time, and enhances the safety, precision, and efficiency of the surgery, fully demonstrating the technological advantages of the deep integration of image navigation and optical control in minimally invasive surgery.

[0046] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A thoracoscope-assisted precise resection intelligent navigation method for lung nodules, characterized in that, The method comprises the following steps: S001, before preoperative flushing, scanning the lung cavity bottom area by low-angle light path, recording the position of the reflection peak line and the dark slope, forming a continuous fluid wave surface boundary band according to the light intensity change, and identifying the light ray propagation refraction change area; S002, based on the fluid wave surface boundary band, analyzing the tilt angle change of the incident light ray point by point, extracting the section where the light ray refraction angle changes abruptly, constructing the refraction jump corridor, and sequentially generating the refraction turning point sequence to establish the light path space positioning anchor point set; S003, according to the light path space positioning anchor point set, setting a micro distance polarization shutter and a variable diaphragm at the front end of the thoracoscope lens, making the incident light ray pass through the refraction jump corridor in the oblique angle narrow beam mode, reducing the reflection instability, and forming an incident optical baseline window with consistent direction and stable brightness; S004, using the incident optical baseline window, uniformly releasing transparent bead chains with the same osmotic pressure characteristics at the edge of the lung cavity bottom, stabilizing the local liquid surface fluctuation through the light and shadow traction effect of the bead chain, forming a static area and constructing a temporary still water tank with optical stability; S005, based on the stable incident path provided by the temporary still water tank, synchronously triggering the reverse breathing window exposure mechanism and the micro-amplitude swing structure of the lens micro-distance rotary wheel under the guidance of the respiratory rhythm control system, making the lens incident angle flexibly adjust according to the respiratory phase, and updating the incident path in real time to stabilize the navigation point coordinates and guide the precise resection operation of the resection tool. 2.The thoracoscope-assisted lung nodule precise resection intelligent navigation method according to claim 1, characterized in that, Step S001 comprises: Before preoperative flushing, scanning the lung cavity bottom area by low-angle light, forming a liquid surface reflection characteristic map; Extracting the continuous reflection boundary in the liquid surface reflection characteristic map to generate a liquid surface light intensity change boundary band; Based on the liquid surface light intensity change boundary band, constructing a refraction jump corridor in the strong reflection disturbance area and setting a refraction turning point sequence; Using the refraction turning point sequence to construct a light path space positioning reference structure, and performing coordinate registration with the preoperative three-dimensional reconstruction image of the lung, for judging the light path deviation and dynamically updating the navigation point in the surgical navigation process. 3.The thoracoscope-assisted lung nodule precise resection intelligent navigation method according to claim 2, characterized in that, Step S002 comprises: In the liquid surface light intensity change boundary band area, collecting reflection images under different incident angles point by point, analyzing the light spot center offset and brightness change to identify the refraction mutation point; Classifying the refraction mutation points in space, constructing the jump corridor and delimiting the measurement section; Setting light path sampling points in the jump corridor, and screening stable points as refraction turning points; Constructing the refraction turning point sequence into a light path space positioning anchor point set, and performing coordinate registration with the preoperative three-dimensional model of the lung. 4.The thoracoscope-assisted lung nodule precise resection intelligent navigation method according to claim 3, characterized in that, The selection of the refraction turning point takes the maximum offset of the light spot on the image plane less than 0.5mm and the brightness value change range within ±8 gray levels as the judgment condition, and the point meeting the condition is the refraction turning point.

5. The intelligent navigation method for thoracoscopically precise pulmonary nodule resection according to claim 3, wherein, Step S003 comprises: According to the light path space positioning anchor point set, adjusting the exit angle of the light source to be consistent with the direction of the anchor point path; Setting a polarization shutter between the light source and the lens to shield the non-axial scattered light and form a linearly polarized light beam; Setting a variable diaphragm in front of the polarization shutter to limit the light beam exit area and diffusion angle to form oblique angle narrow beam incident light; Oblique narrow beam incident light is guided to the refractive jump corridor to establish an incident optical baseline window and correct the navigation point coordinates in real time.

6. The intelligent navigation method for thoracoscopically precise pulmonary nodule resection according to claim 5, wherein, The polarization shutter is a linear polarizer structure, and the transmission axis direction is adjusted by an electric control rotating device to be parallel to the light beam propagation direction. The diaphragm is a multi-leaf closed structure, and the exit opening is controlled by a micro-step motor to make the incident light enter the refractive jump corridor with a smaller preset divergence angle.

7. The intelligent navigation method for thoracoscopically assisted precise resection of pulmonary nodule according to claim 5, characterized in that, Step S004 includes: According to the spatial trend of the incident optical baseline window on the cavity bottom, the coordinates of the starting point and the ending point of the path are calculated and transparent bead chains are arranged on both sides; The bead chains are irradiated by low-angle incident light to form a light shadow traction belt to stabilize the liquid surface fluctuation; A temporary still water tank is formed at the center of the cavity bottom under the action of the bead chains, and an incident light beam is projected to verify the optical stability; A transparent fixed ring is arranged outside the still water tank to maintain the stability of the liquid surface shape to ensure the continuity of the surgical navigation light path.

8. The intelligent navigation method for thoracoscopically precise pulmonary nodule resection according to claim 7, wherein, The transparent bead chain is made of polylactic acid glycolic acid copolymer, filled with isotonic gel inside, and the shell is sterilized. The distance between the beads is uniform, and the beads form a continuous light shadow belt after being irradiated, which produces traction interference stripes on the liquid surface to suppress the liquid surface fluctuation, and the fixed ring stabilizes the liquid surface boundary to maintain the stability of the optical path.

9. The intelligent navigation method for thoracoscopically assisted precise resection of pulmonary nodule according to claim 7, characterized in that, Step S005 includes: Based on the stable incident path provided by the temporary still water tank, the respiratory phase data is obtained by the respiratory rhythm acquisition device and the respiratory phase space mapping table is established; According to the respiratory phase change, the exposure structure of the reverse phase breathing window is adjusted to match the lung movement; Synchronously drive the micro-distance rotary wheel at the front end of the scope to compensate the incident angle to keep the light beam direction stable; Real-time update of the navigation point space coordinates and guide the resection cutter to perform precise resection operation along the corrected path.

10. The intelligent navigation method for thoracoscopically precise pulmonary nodule resection according to claim 9, wherein, The phase synchronization control relationship is established between the respiratory rhythm acquisition device and the micro-distance rotary wheel at the front end of the scope, and the incident angle change curve of the scope is kept synchronous with the respiratory rhythm waveform through real-time feedback signals, so that the light beam always penetrates the center area of the still water tank vertically and continuously focuses on the lesion target position, realizing the dynamic matching of the navigation light path and the lung movement.

Images