CN108354651B - Cutting guide for sizing a replacement flap for a soft tissue surface - Google Patents

Abstract

The invention relates to the field of medical treatment, and discloses a method for preparing a cutting guide plate for determining the size of a skin flap substituted on the surface of soft tissue by utilizing digital spatial reconstruction and 3D printing, which comprises the following steps: 1) acquiring thin-layer CT data of a patient through CT scanning, reconstructing the soft tissue model form and the tumor form of a patient area, and acquiring editable three-dimensional model data; 2) editing the three-dimensional model, planning a repair scheme, calibrating a safe excision boundary of lesion tissues, determining an excision lesion area, extracting a repair curved surface, and calculating a curved surface required by conversion; 3) converting the curved surface into a plane through calculation, and thickening the plane to obtain a three-dimensional flat plate model; 4) and 3D printing to obtain the cutting guide plate. The cutting guide plate prepared by the invention can accurately cut and replace a skin flap in a supply area, thereby realizing the most accurate conformal function reconstruction of a receiving area with the minimum damage of the skin flap supply area.

Description

Cutting guide for sizing a replacement flap for a soft tissue surface

Technical Field

The invention relates to the field of medical treatment, in particular to a method for preparing a cutting guide plate for determining the size of a skin flap substituted on the surface of soft tissue by utilizing digital spatial reconstruction and 3D printing.

Background

After tumor resection, the space left by the removed soft tissue needs to be filled and repaired, and the repair of complex soft tissue defects is extremely challenging for the surgeon. The current major means of repairing soft tissue defects include pedicle flaps, free flaps, and artificial substitutes. At present, on the premise of safety of a tumor resection boundary, more functional peripheral soft tissues need to be reserved, and the appearance, the function and the tissue volume of a reconstructed organ are recovered as much as possible. Also, in the face of cases where large-area defects after tumor resection involve multiple soft tissue subregions, there is often a lack of precise preoperative design and intraoperative strain. On the other hand, when repairing soft tissue defects with skin flaps, it is necessary to minimize defects and injuries in the donor area. When cutting and taking the substitute flap, need place the cutting baffle in flap confession district surface, realize the accurate cutting of flap with the help of the profile of cutting the baffle. The dimensional accuracy of the cut-out guide plate determines whether defects and damage to the supply area can be minimized. Although some research attempts to solve these problems, precise consistency between the skin flap receiving area and the skin flap supply area cannot be achieved. To achieve these goals, preoperative planning, intraoperative performance and postoperative assessment are required to be as accurate as possible.

The application of digital medicine can help us solve these problems. At present, the bone tissue repair technology based on digital medical assistance is mature. For example, chinese patent application No. CN201710052022.6 discloses a multi-degree-of-freedom 3D printing method for a skull substitute, which prints out a skull substitute having certain biological and mechanical properties by using a fused deposition modeling technique. The method comprises the following steps: carrying out three-dimensional imaging on the skull to obtain the original data of the geometrical size of the skull; establishing a three-dimensional model of the skull; layering the three-dimensional model according to the shape of the skull, and converting the three-dimensional model into section data; selecting a printing material; setting printing parameters; and performing multi-degree-of-freedom 3D printing. During printing, the printing is performed alternately along the warp and weft directions, and each layer is printed according to the contour direction of the skull. The invention adopts a multi-degree-of-freedom mechanical arm device, can realize 3D printing at any angle and any motion trail, and improves the mechanical property of the skull substitute. The invention can accurately control the shape and printing direction of each layer in the printing process, improve the printing precision and realize the rapid manufacture of the skull substitute with specific mechanical properties.

However, the application of the digital spatial reconstruction and 3D printing technology in the precise repair of soft tissue is slow, and the application of the digital technology in the prior art to the free soft tissue flap is mainly focused on the positioning of the perforator blood vessel of the flap, but the related reports of the main technical indexes provided by the invention are not available, mainly because the spatial form of the soft tissue has the compatibility, and the data acquired before the operation and the operation have uncertainty.

Chinese patent application No. CN201510205200.5 discloses a method for manufacturing an individual precise breast prosthesis based on a three-dimensional printing technology. The method comprises the steps of analyzing and positioning a tumor to be excised before an operation according to medical image data of a breast of a patient, determining the shape, size and position of an excised part, establishing a three-dimensional digital tumor model, comprehensively considering the requirements of radical treatment of the tumor of the patient and personalized integral cosmetology during breast reconstruction, optimally designing a three-dimensional model of a breast prosthesis according to the established tumor model and a breast shaping gold method, selecting a biocompatible material conforming to the hand feeling and texture of the breast, and printing and forming by using a biological three-dimensional printing technology.

However, the patent discloses printing a mammary prosthesis that is intended to be filled in the subcutaneous tissue rather than the soft tissue surface, and the difference between the two is that the 3D printed mammary prosthesis is a three-dimensional model that can be filled directly without the aid of a cutting guide. And the implant is a prosthesis, so that potential rejection risks exist, and a series of serious medical problems such as long-term rupture, absorption, position transfer and the like exist. The adoption of the autologous soft tissue vascularization transplantation has no problems because the defect part is filled with autologous tissues. In addition, although the soft tissue surface is also a three-dimensional model (part of the cortical surface such as the nose, jaw and mouth is uneven), the skin flap supply area for replacement is generally the soft tissue cortex, the cut replacement skin flap is a curved surface which is approximately planar, and the shape and size of the cutting guide plate should be fit with the supply area surface and be approximately planar or plane. Therefore, how to accurately determine the size of the cutting guide plate becomes a technical problem (in the prior art, the cutting guide plate is generally prepared and the flap cutting is performed mainly by the personal experience of a doctor instead of establishing a three-dimensional model, which is high for the personal requirement of an operator and is a challenge for a novice with less experience).

Disclosure of Invention

In order to solve the technical problems, the invention provides a method for preparing a cutting guide plate for determining the size of a substitute flap on the surface of a soft tissue by utilizing digital space reconstruction and 3D printing.

The specific technical scheme of the invention is as follows: a method of preparing a resection guide for determining a soft tissue surface replacement flap size using digital spatial reconstruction and 3D printing, comprising the steps of:

1) and acquiring thin-layer CT data of a patient through CT scanning, reconstructing the soft tissue model form and the tumor form of a patient area, and acquiring editable three-dimensional model data.

2) Editing the three-dimensional model, planning a repair scheme, calibrating a safe excision boundary of lesion tissues, determining an excision lesion area, extracting a repair curved surface, and calculating the curved surface required by conversion.

3) The curved surface is converted into a plane with a specific form through calculation, then the plane is thickened to obtain a three-dimensional flat plate model, and related format data are stored.

4) And (4) adopting a 3D printing technology after importing the data to manufacture a cutting guide plate for determining the size of the substitute flap.

In the prior art in the field, the application of the digital spatial reconstruction and 3D printing technology in the precise repair of soft tissues is slow, mainly because the spatial morphology of the soft tissues has the flexibility, and the data collected before the operation and the uncertainty exist in the operation; meanwhile, since the surface of the affected area is usually an irregular three-dimensional curved surface, and the surface of the donor area is usually a curved surface which is approximately planar (such as the surface of a thigh) or a curved surface which is greatly different from the curved surface of the affected area, it is a difficult problem how to accurately maintain the size consistency of the skin flap and the surface of the affected area, so that the cutting guide plate cannot be prepared and the cutting of the skin flap cannot be assisted by the traditional simple 3D printing technology at present. Currently, the sizing of the cut guide plate can only be determined by the experience of a doctor or rough estimation, and the accuracy is not high. For the sake of insurance, usually, a certain amount of skin flap is cut, and then the skin flap is cut according to the actual situation, which not only increases the damage of the patient supply area, but also increases the operation time and difficulty because the skin flap can not be cut accurately at one time.

Therefore, the team of the invention creatively provides a concept of converting the three-dimensional curved surface of the receiving area surface into a two-dimensional plane firstly through long-term research, and then prepares the flat cutting guide plate by means of a 3D printing technology according to the two-dimensional plane, so that the cutting guide plate can keep high consistency with the size of the receiving area surface, and therefore, the flap cut by the cutting guide plate can also keep high consistency with the size of the receiving area surface, thereby overcoming the difficulty that the soft tissue flap cutting guide plate is difficult to prepare and use for soft tissue flap preparation by using a digitization technology and a 3D printing technology at present.

Preferably, in step 1), the layer thickness of the CT scan is 2mm or less.

Preferably, in step 1), the acquired thin-layer CT data is converted into a DICOM data format and then introduced into six-dimensional DENTAL implant design software (6D-digital Tech Co, Ltd, China) to reconstruct the soft tissue model form and the tumor form of the patient region, and editable stl format model data is acquired.

Preferably, in the step 2), editing the three-dimensional model by combining magics design software and Geomagage Studio design software, planning a repair scheme, calibrating a focus tissue resection boundary by comprehensively considering a tumor resection safety range, and determining a focus resection area; and then extracting the repaired curved surface through Geomagage Studio design software, and calculating and converting the repaired curved surface into a Nurbs curved surface.

Preferably, in step 3), after obtaining the Nurbs curved surface, adjusting the curved surface nodes through Rhino design software, flattening the curved surface towards a specific direction to obtain a plane with a specific form, thickening the plane to obtain a three-dimensional flat plate model, and storing the three-dimensional flat plate model as stl format data.

The biggest problems encountered by the team of the invention in the research process are: how to convert a three-dimensional curved surface into a two-dimensional curved surface simply, conveniently and accurately. In the prior art, no ready and mature software can conveniently and accurately convert a three-dimensional curved surface into a two-dimensional curved surface, and although manual calculation can also achieve the purpose, the manual calculation in the process is too complex and difficult to achieve and is not the expertise of medical workers, so that the requirement on the medical workers is too high, the implementation is difficult, the manual calculation workload is large, the consumed time is long, and errors are easy to occur.

The present team recognizes that the most desirable software should be capable of "one-touch conversion" (capable of converting CT scan acquired data into a digitized model of the cutting guide in one piece of software), and that the present team is also under development in a tight drum. Before the development of this software, the team of the present invention also found an alternative: by widely understanding, various professional software in various industries at present is integrated, and the invention aims are realized by utilizing the mutual cooperation of various kinds of software in different fields. Although the software is ready-made and not a development result of the team of the invention, the creativity of the invention cannot be denied. The team of the present invention pays a lot of efforts in the process of understanding and collecting the above various cross-domain professional software, needs to understand and learn the professional knowledge beyond the domain (the software has strong professional use and operation, and the ordinary skilled person in the art does not master the technology), and usually, the integration of the above various software is difficult because the skilled person in the art has limited knowledge about the software outside the domain, so the integration process pays a lot of creative labor.

Although the learning process of the software is time-consuming and labor-consuming, almost all cases can be dealt with once and for all as long as the method is mastered; the manual calculation method needs a large amount of calculation for each case due to different specific situations of different cases, so that the workload is larger in the long term, and the individual requirements of medical workers are higher.

Preferably, in step 3), when the curved surface is converted into a plane surface, the plane surface is selected from a plurality of conversion schemes according to the principle that the plane surface is obtained to facilitate the cutting of the flap.

In the process of converting a three-dimensional curved surface into a plane, a plurality of parallel conversion schemes may exist, and the team of the invention summarizes after a plurality of tests or practice processes: if the shape of the resulting plane is not regular enough or the edge is very tortuous and not smooth enough, the difficulty of the operation is increased during the flap cutting process, which may cause the shape of the finally cut flap to be inconsistent with the design. Meanwhile, when the skin flap is sutured with the receptor region, the operation difficulty is increased.

Preferably, in the step 4), the material of the cutting guide plate is a medical photosensitive resin material.

Preferably, the photosensitive resin material is a flexible photosensitive resin material.

According to the skin flap cutting device, after the three-dimensional curved surface is converted into the two-dimensional plane, the flat cutting guide plate is manufactured through 3D printing, and finally the cutting guide plate is placed on the surface of the supply area to cut the skin flap, so that the precise cutting of the skin flap is realized. However, since the donor area surface is not a true plane, especially when the area of the flap required is large, the curvature of the donor area surface is more pronounced. The texture of the existing cutting guide plate is hard usually and cannot be bent, so that the cutting guide plate cannot be highly attached to the surface of a supply area under certain conditions, and the accuracy is affected. Therefore, the cutting guide plate is improved, and the cutting guide plate is made of flexible materials, so that the cutting guide plate can be bent to a certain degree and is completely attached to the surface of the supply area.

The invention also provides another alternative, a method for preparing a cutting guide plate for determining the size of a skin flap replacing soft tissue surface by using digital space reconstruction and 3D printing, comprising the following steps of:

1) and acquiring thin-layer CT data of a patient through CT scanning, reconstructing the soft tissue model form and the tumor form of a patient area, and acquiring editable three-dimensional model data.

2) Editing the three-dimensional model, planning a repair scheme, calibrating a safe excision boundary of lesion tissues, determining an excision lesion area, extracting a repair curved surface, calculating a curved surface required by conversion, and storing related format data.

3) And (3) importing the data, and then adopting a 3D printing technology to prepare a curved surface physical model by taking flexible photosensitive resin as a material.

4) And flattening the curved surface physical model in a tiling or/and cutting mode to obtain the planar cutting guide plate.

In the former case, the three-dimensional curved surface is converted into the two-dimensional curved surface, and then the cutting guide plate is printed, while in the latter case, the three-dimensional cutting guide plate is printed by using a material with good flexibility (such as silica gel). Compared with the prior art, the method has the advantages that the complex process of converting the three-dimensional curved surface into the two-dimensional plane is omitted under the condition that no existing mature software exists, the requirement on medical workers is low, and almost all ordinary people can realize the process. Of course, the latter solution has the disadvantage that the simulation operation of the conversion scheme cannot be easily performed (the former can be simulated in software to select the optimal conversion scheme), and if the simulation operation is to be performed in the latter scheme, the simulation operation can be performed only by printing a plurality of cutting guide plates.

Preferably, in step 1), the layer thickness of the CT scan is 2mm or less.

Preferably, in step 1), the acquired thin-layer CT data is converted into a DICOM data format and then imported into six-dimensional dental implant design software to reconstruct the soft tissue model form and the tumor form of the patient area, and editable stl format model data is acquired.

Preferably, in the step 2), editing the three-dimensional model by combining magics design software and Geomagage Studio design software, planning a repair scheme, calibrating a focus tissue resection boundary by comprehensively considering a tumor resection safety range, and determining a focus resection area; and then extracting the repaired curved surface through Geomagage Studio design software, and calculating and converting the repaired curved surface into a Nurbs curved surface.

Preferably, in step 4), the curved physical model is flattened, so that the obtained plane shape is convenient for cutting the flap, and the scheme with the most regular obtained plane shape is selected from a plurality of alternatives.

Preferably, in the step 4), the flexible photosensitive resin material is a relatively soft and easily-cut material such as photosensitive silica gel.

Compared with the prior art, the invention has the beneficial effects that:

1. displaying a safe tumor resection boundary, and performing preoperative virtual surgery;

2. obtaining the excision range and access of the soft tissue surface, accurately excising the tumor in the minimum range, and reserving the adjacent soft tissue with important functions to the maximum extent;

3.3D printing technology is used for manufacturing a soft tissue flap cutting guide plate, and the most accurate conformal function reconstruction of a receiving area is obtained by using the smallest flap for area damage;

4. the operation can be carried out by two groups of personnel (the excision of the soft tissue of the affected area and the excision of the skin flap of the donor area) at the same time, thereby saving the operation time;

5. the requirement on the experience of medical workers is low, the method is suitable for surgeons with insufficient experience, and the learning period is shortened.

Drawings

FIG. 1 is a schematic view of the main flow of the operation of example 1;

FIG. 2 is a CT scan of example 1;

FIG. 3 is a CT scan of example 1;

FIG. 4 is a diagram of the soft tissue model and tumor model reconstruction in the tumor region using the design software in example 1;

FIG. 5 is a CT scan of example 2;

FIG. 6 is a CT scan of example 2;

fig. 7 is a schematic view of the main flow of the operation of example 2.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1

Patients were all, male, 34 years old.

And (4) the ulcer of the right tongue appears after 2 months, the patient is in a local hospital for treatment, and the ulcer of the tongue is considered and is treated in an anti-inflammatory mode. The swelling is obviously enlarged and the pain is aggravated in nearly one month.

Biopsy: "tongue" is consistent with well-differentiated squamous cell carcinoma.

Physical examination: a lump in the right tongue of about 4cm in size, ulcerated, restricted tongue movement, multiple swollen lymph nodes in the right upper neck.

And (3) diagnosis: malignant tumor of tongue

As shown in fig. 1-4, the procedure includes the following steps:

1) thin-layer CT data (the layer thickness is 0.2 mm) of a patient are obtained, the thin-layer CT data are converted into a DICOM data format, six-dimensional DENTAL implant design software (6D-digital Tech Co, Ltd, China) is introduced to reconstruct soft tissue model forms and tumor forms of a patient area, and editable model data in stl format are obtained.

2) Editing The three-dimensional model by combining magics (material Ltd, The Kingdom Of Belgium) design software and Geomagne Studio design software (Geomagne, USA), planning a repair scheme, calibrating a focus tissue excision boundary (as shown in figure 4) by comprehensively considering The tumor excision safety range, and excising a focus area; and then extracting the repaired curved surface through Geomagage Studio design software, and calculating and converting the repaired curved surface into a Nurbs curved surface.

3) After obtaining the Nurbs curved surface, adjusting the curved surface nodes through the design software of Rhino (Robert McNeel Ltd, USA), flattening the curved surface towards a specific direction, obtaining a plane with a specific shape (when the curved surface is converted into the plane, the plane shape is convenient for cutting a flap, and a scheme with the most regular plane shape is selected from a plurality of conversion schemes), then thickening the plane to obtain a three-dimensional flat plate model, and storing the three-dimensional flat plate model as stl format data.

4) The processing adopts a 3D printing mode, in the case, a connexTM 350 printer (stratasys Ltd, USA) is adopted for processing and manufacturing, and a flexible photosensitive resin material (Objet MED 610, Objet Ltd, Israel) is adopted for manufacturing and finishing the 3D printing flap cutting guide plate.

The patients underwent surgery under general anesthesia at 2017-10-10, and the intraoperative exploration shows: the tumor is mainly located in the right tongue body and the bottom of the mouth, the size is about 4 x 3cm, the texture is hard, the boundary is not clear, the root of the right tongue and the side wall of the oropharynx are affected, and the main body of the tumor crosses the median line of the tongue. Multiple enlarged lymph nodes were visible in the bilateral neck, with the larger located in the upper right neck, approximately 2 x 1.5cm in size and medium in texture. A group of surgeons finishes cleaning lymph nodes in the I-V area of the right neck and the I-III area of the left neck, then processes a primary focus, completely removes tumors along the preoperative designed safety boundary, removes the tongue 3/4, retains the residual tongue body at the root of the left tongue, and indicates negative by freezing the incisal margin in the operation. Another group of surgeons simultaneously prepared the left femoral anterolateral flap: making a longitudinal incision along the left thigh, searching a skin flap perforator by a preoperative Doppler ultrasonic probe, positioning the skin flap perforator by using the X, taking a skin flap blood vessel perforator positioning point as a center, and taking a soft tissue guide plate as a skin flap preparation surface range to prepare a free skin flap on the front outer side of the left thigh. Finding out subcutaneous perforator with perforator positioning point, dissecting free posterior femoral artery descending branch and accompanying vein in retrograde motion, cutting skin flap along soft tissue guide plate calibration range, breaking pedicle, washing anticoagulant, placing free skin flap at neck, anastomosing blood vessel (the posterior femoral artery descending branch is anastomosed with right superior thyroid artery, and the two accompanying veins are anastomosed with right side vein and superior thyroid vein respectively), checking blood flow smoothness, providing good skin margin blood, and sewing skin flap at oral cavity and right oropharyngeal defect for shaping. The operation cavity is washed to stop bleeding, a drainage tube is placed, and the incision is sutured. The trachea is cut open and the trachea cannula is inserted to assist ventilation and sputum excretion. After the operation, the patient is sent to ICU for monitoring treatment.

Example 2

The patient is a person, male, age 58.

2016.5 oral cavity: squamous cell carcinoma of the floor of mouth (mesodifferentiation). Esophagus: esophageal hypodifferentiation (squamous) carcinoma with esophageal distance of 29-31cm from incisor.

2016-8-10, go to the field of' 1. enlarged excision of malignant tumor at the bottom of mouth; 2. partial excision of malignant tumor of tongue; 3. cervical lymphadenectomy (bilateral); 4. tracheotomy; 5. partial mandibular resection (titanium plate reconstruction); 6. reconstructing the right pectoralis major; 7. mouth bottom reconstruction.

Postoperative pathology: 1. (bottom of mouth) high-medium-low differentiated squamous cell carcinoma (tumor 4.5X 3.5X 2.7 cm), infiltrates into submucosal and striated muscle tissues, and involves salivary glands, mandible and nerve tissues. 2. (area II and III of left neck) 10 and (area III of right neck) 23 chronic lymphadenitis, and part of submaxillary gland tissue. Remarking: 1. negative in all cases (lingual ventral, left, right, basal margin). 2. No clear aneurysm plugs were visible in the sections.

2016.9 the malignant tumor of esophagus is treated by radiotherapy but the bottom of mouth is not treated by radiotherapy, and the tumor of esophagus does not recur at present.

2017.9.13 Hospital CT finds a lump in the soft tissue of the right mandible area.

2017.9.21 puncture of the right cheek lump in the outer yard: seen in scattered and small nuclei of large and abnormal cells, and considered as malignant tumor cells, biopsy is suggested for definition.

The history of diabetes, oral administration of "Dameikang" treatment, blood sugar control is good.

Physical examination: generally, vital signs are stable, the size of the right submandibular swelling is 6cm, the skin surface is raised, the surface is red and swollen, the local skin is affected by 4 multiplied by 4cm, the tumor corresponds to the affected oral mucosa of 2 multiplied by 2cm, the local mandible is affected, the local mandible is hard and fixed, no pain exists in the operation scar of the neck, and the other two neck parts are not obviously swollen.

Preoperative diagnosis: after operation of malignant tumor at mouth bottom; 2. after esophageal malignant tumor radiotherapy; 3. diabetes mellitus; 4. lung space occupying lesions; 5. hepatitis B minor three positive.

As shown in fig. 5-7, the procedure includes the following steps:

1) CT data of a patient thin layer (0.2 mm) is obtained through CT scanning, then the data is converted into a DICOM data format and then introduced into six-dimensional DENTAL implant design software (6D-DENTAL Tech Co, Ltd, China) to reconstruct the soft tissue model form and the tumor form of a patient region, and editable stl format model data is obtained.

2) Editing The three-dimensional model by combining magics design software (Materialise Ltd, The Kingdom Of Belgium) and Geomagnee Studio design software (Geomagnee, USA), planning a repair scheme, calibrating a focus tissue resection boundary by comprehensively considering a tumor resection safety range, and determining a focus resection area; and then extracting the repaired curved surface through Geomagage Studio design software, and calculating and converting the repaired curved surface into a Nurbs curved surface.

3) After obtaining the Nurbs curved surface, adjusting the curved surface nodes through Rhino design software (Robert McNeel Ltd, USA), flattening the curved surface towards a specific direction, obtaining a plane with a specific shape (when the curved surface is converted into the plane, the plane shape is convenient for cutting a flap, and a scheme with the most regular plane shape is selected from a plurality of conversion schemes), then thickening the plane to obtain a three-dimensional flat plate model, and storing the three-dimensional flat plate model as stl format data.

4) And importing the data, processing the data in a 3D printing mode, and manufacturing a cutting guide plate for determining the size of the substitute flap. This case used a connex model 350 printer (stratasys Ltd, USA) and the material used was a flexible photosensitive resin material (Objet MED 610, Objet Ltd, Israel).

5) Tumor resection and flap excision.

6) And (5) suturing the skin flap.

Example 3

The difference between this embodiment and embodiment 1 is that the three-dimensional model is printed as a curved surface physical model, and the method specifically includes the following steps:

1) CT data of a patient thin layer (0.2 mm) is obtained through CT scanning, then the data is converted into a DICOM data format and then introduced into six-dimensional DENTAL implant design software (6D-DENTAL Tech Co, Ltd, China) to reconstruct the soft tissue model form and the tumor form of a patient region, and editable stl format model data is obtained.

2) Editing The three-dimensional model by combining magics design software (Materialise Ltd, The Kingdom Of Belgium) and Geomagnee Studio design software (Geomagnee, USA), planning a repair scheme, calibrating a focus tissue resection boundary by comprehensively considering a tumor resection safety range, and determining a focus resection area; and then extracting the repaired curved surface through Geomagage Studio design software, calculating and converting the repaired curved surface into a Nurbs curved surface, and storing the Nurbs curved surface as related format data.

3) And importing the data, and then adopting a 3D printing technology and taking photosensitive silica gel as a material to prepare the curved surface physical model.

4) The curved physical model is flattened by way of tiling and cutting (when the curved physical model is flattened, the obtained plane shape is convenient for cutting the skin flap as a principle, and a scheme with the most regular obtained plane shape is selected from a plurality of alternatives. ) Thus, a planar cutting guide plate is obtained.

The raw materials and equipment used in the invention are common raw materials and equipment in the field if not specified; the methods used in the present invention are conventional in the art unless otherwise specified.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, alterations and equivalents of the above embodiments according to the technical spirit of the present invention are still within the protection scope of the technical solution of the present invention.

Claims (3)

1. A cutting guide for sizing a replacement flap of a soft tissue surface, the method comprising the steps of:

1) acquiring patient thin-layer CT data through CT scanning, converting the acquired thin-layer CT data into a DICOM data format, introducing the DICOM data into six-dimensional dental implant design software to reconstruct the soft tissue model form and the tumor form of a patient area, and acquiring editable stl format model data;

2) editing the three-dimensional model by combining magics design software and Geomagage Studio design software, planning a repair scheme, calibrating a focus tissue resection boundary by comprehensively considering a tumor resection safety range, and determining a focus resection region; then extracting the repaired curved surface through Geomagage Studio design software, and calculating and converting the repaired curved surface into a Nurbs curved surface;

3) after data are imported, a 3D printing technology is adopted, and flexible photosensitive resin is used as a material to prepare a curved surface physical model;

4) and flattening the curved surface physical model in a tiling or/and cutting mode to obtain the planar cutting guide plate.

2. The cutting guide of claim 1, wherein in step 1), the layer thickness of the CT scan is 2mm or less.

3. The cutting guide of claim 1, wherein in step 4), the flat surface shape is flattened to facilitate cutting of the flap, and the most regular flat surface shape is selected from several alternatives.

Images