Objective: Autologous lymph nodes fragmentary transplantation combined with vascular endothelial growth factor-C (VEGF-C) on athymic nude mice to explore the association between regeneration of lymphatic vessel and tumor cell migration. Methods: A total of 45 nude mice were randomly divided into 3 groups: Group A, simple autologous lymph nodes fragmentary transplantation, n=15; Group B, autologous lymph nodes fragmentary transplantation together with VEGF-C, n=15; Group C, without any intervention, n=15. At 1 month, 2 months and 6months after surgeries, the axillary lymph nodes of 5 mice in each group were dynamically examined by in vivo indocyanine green (ICG) fluorescence imaging respectively. The regenerated lymph nodes and relevant skin were evaluated using hematoxylin-eosin (H&E) staining and the skin was quantitatively analyzed via immunofluorescence staining for lymphatic vessel endothelial hyaluronan receptor 1(LYVE-1) as well. Results: One month after surgery, the right regenerated axillary lymph nodes in group B (5/5) were visible by in vivo ICG fluorescence imaging, whereas the same signals were not detected in group A (0/5). The results were the same at 2 and 6 months after surgery. HE staining showed that the cortical, paracortical, and medullary regions of the right axillary lymph nodes of the experimental group B were clear, and the lymphatic vessel structure was present, accompanied by lymphocyte infiltration. Immunofluorescence staining of the right upper limb showed that the expression of LYVE-1 in the lymphatic endothelium of the B group was significantly higher than that in group A (P<0.001) and the control group (both P<0.001). Conclusions Due to the promising consequence of regenerated lymph nodes, the procedure of autologous lymph nodes fragmentary transplantation combined with VEGF-C in athymic nude mice provides a reliable animal model for the next stage research.

As emerging digital technologies, virtual reality and augmented reality technology have been widely and deeply applied in the medical field, especially in plastic surgery. This paper reviewed the development of virtual reality and augmented reality technology, indispensable components in realization process of virtual reality and augmented reality technology in plastic surgery as well as applications in preoperative planning, intraoperative navigation, surgical training of plastic surgery. At last, there is a summary of the applications, deficiencies and the future direction of virtual reality and augmented reality technology in plastic surgery.

Objective:To construct a system HE-01 for the treatment of microtia based on HoloLens and verify the feasibility the application of HE-01 in ear reconstruction.Methods:Six volunteers and six patients with microtia were recruited from Plastic Surgery Hospital of Chinese Academy of Medical Sciences from August to September 2021. Mimics Research and 3-matic research software were used to construct a virtual three-dimensional auricle model. Based on HoloLens and occlusal splint navigation marker device, the virtual-real interactive system HE-01 for the treatment of microtia was constructed. The registration accuracy, tracking delay and display effect of HE-01 were evaluated through repeated experiments of volunteers. The operation process was defined through repeated experiments of patients and the feasibility of applying HE-01 in auricular reconstruction was verified.Results:HE-01 was built successfully and the operation flow was clear. The experiment of volunteers showed that under different angles, the registration accuracy was high (less than 2.7% of the bilateral auricle size difference of normal people), the tracking delay was low (less than 0.1s), and the green and red display effect of virtual auricle guide was the best. Experiments of patients with microtia showed that HE-01 could be applied to auricular reconstruction, and there were no obvious complications in wearing the navigation marker device, which had repeatability and stability.Conclusion:This study has completed the conceptual design of augmented-reality assisted auricular reconstruction based on navigation device, CT data and HoloLens. HE-01 has good registration accuracy, tracking speed and display effect, laying a good foundation for further software development and clinical transformation.

Objective:To construct a virtual-real interactive system HE-01 for the treatment of microtia based on HoloLens and verify the feasibility of applying HE-01 in ear reconstruction.Methods:Six volunteers (3 males and 3 females, average age: 20.5 years old) and six patients with microtia(3 males and 3 females, average age: 7.6 years old) were recruited from Plastic Surgery Hospital of Chinese Academy of Medical Sciences from August to September 2021. The Mimics Research 21.0 software and 3-matic research software were used to construct a virtual three-dimensional auricle model. Based on HoloLens and occlusal splint navigation marker device, the virtual-real interactive system HE-01 for the treatment of microtia was constructed. The registration accuracy, tracking delay and display effect of different colors (red, green, blue and skin color) of HE-01 were evaluated through repeated experiments of volunteers. The operation process was defined through repeated experiments of patients and the feasibility of applying HE-01 in auricular reconstruction was verified.Results:HE-01 was built successfully and the operation flow was clear. The experiment of six volunteers (12 ears) showed a high registration accuracy (average error rate 2.3%-2.4%, less than 2.7% of the bilateral auricle size difference of normal people), low tracking delay (six volunteers were all less than 0.1 s), and best green and red display effect of virtual auricle guide under different angles (-60°, -30°, 0°, 30°, 60°). Experiments of patients with microtia showed that HE-01 could be applied to auricular reconstruction, and there were no obvious complications in wearing the navigation marker device, which had repeatability and stability.Conclusion:This study has completed the conceptual design of augmented-reality assisted auricular reconstruction based on navigation device, CT data and HoloLens. HE-01 has good registration accuracy, tracking speed and display effect, laying a good foundation for further software development and clinical transformation.

Objective:To design a real time dynamic three-dimensional(3D) auricular image guidance based on sensors and make an evaluation of it.Methods:One commercial head model and 3 volunteers (2 men and 1 woman, aged 24-27 years old) recruited from Plastic Surgery Hospital, Chinese Academy of Medical Sciences in August 2019 were studied. Digital models of auricle were made using CT data of three volunteers with ITK-SNAP 3.6.0 and MeshLab (V 2016.12.23). The optimal number of sensors was three and the optimal location of sensors was one side of the eyebrow, the nasal tip and the inferior point of the earlobe. The virtual model was connected with the real auricle based on three sensors. The 3D auricular image was projected to the corresponding real auricle through the projector. The infrared motion-capture device was used to capture the changes of the position of the sensors to realize real-time tracking. The matching accuracy between 3D auricular image and real auricle was evaluated by calculating the coincidence error rate after registration, calculating the coincidence error rate, image deformation and tracking latency during tracking.Results:The average coincidence error rate after registration was 2.5% (the difference between the normal bilateral ears was 2.7%), which showed the registration precision was high. The coincidence error rate was lower than 2.7% in certain rotation angle (30° clockwise) and the image deformation was lower than 2.6% in certain rotation angle (30° clockwise and 15° counterclockwise) during tracking, which demonstrated the precision of tracking head movement was high and image deformation was low in a certain rotation range. The time of image update and motion tracking was less than 0.1 s, which satisfied the requirement of surgery.Conclusions:This study demonstrates that the fabrication of real-time dynamic 3D auricular image guidance based on sensors is feasible and the image guidance has high accuracy of registration and tracking, low image deformation and fast tracking speed, which lays a foundation for its application in clinical auricle reconstruction in the future.

Objective:Facial artery is the main blood supply source of facial soft tissue, which has an important influence on facial plastic surgery and injection procedures. There are many types of facial arteries. They have wide coverage, and travel several layers. In this study, the detailed characteristics of the facial arteries were revealed by cadaver dissection.Methods:In 19 donated fresh cranial (28 sides) specimens, the facial arteries were dissected. And then the type, layer, relationship with nasolabial groove, length, diameter, distance from the oral commissure, branches and submental artery were observed and measured.Results:Facial arteries were found in all cadavers, starting from the external carotid arteries, branching submental arteries below the mandibular margins, ascending to the anterior edge of the masseter muscles, crossing the mandibles and entering the faces. After entering into the faces, the facial arteries branched the submental arteries(100%, 28/28), lower labial arteries (100%, 28/28), upper labial arteries (100%, 28/28), lateral nasal arteries (92.9%, 26/28) and the angular arteries (57.2%, 16/28) throughout the courses. According to the vascular route, the facial artery was classified into four types. In TypesⅠ(8 sides), all branches were included and the angular arteries arose directly from the lower segment of the facial arteries (28.6%). In TypesⅡ(8 sides), all branches were included and the angular arteries were the terminal branches (28.6%). In TypesⅢ(10 sides), angular arteries were absent (35.7%). In Type Ⅳ (2 sides), angular arteries and lateral nasal arteries were absent (7.1%). The lower segment of facial artery coursed under the facial expression muscles, and continued to the middle segment at the point which was (26.0±5.0) mm away from the oral commissure on the lateral side. The layer that the facial artery coursed was varied. It passed through the superficial layer of the facial expression muscles. After passing the horizontal line parallel to the lower margin of nasal sill, the upper segment continued to on the superficial layer of the facial expression muscles. The facial arteries were mostly located medial to the nasolabial fold(24 sides, 85.7%) and occasionally across the nasolabial fold(4 sides, 14.3%). The lengths of the upper, middle and lower segments of facial artery were (26.4±10.9) mm, (29.7±8.4) mm, and(33.5±6.9) mm, respectively. The diameters in starting point of upper, middle and lower sections were(2.45±0.48) mm, (1.85±0.12) mm, and (1.09±0.21) mm, respectively. The facial artery passed lateral to the oral commissure and the distance from the intersection of the horizontal line to the oral commissure was (26.0±5.0) mm. The starting point of the superior labial artery locacted below the horizontal line was (8.0±1.4)mm away from the horizontal line of the oral commissure and(55.0±5.2) mm from the mandibular angle. The starting point of the inferior labial artery located below the horizontal line was (17.1±11.1) mm from the horizontal line of the oral commissure, and the distance from the mandibular angle was (44.2±5.2) mm. The diameter of the submental artery in its starting point was (1.4±0.1) mm. The distance from the starting point of the submental artery to the horizontal line of the oral commissure was (34.9±2.6) mm, and the distance from the mandibular angle was (29.4±5.8) mm. The starting point of the submental artery was (6.4±0.8) mm from the lower margin of the mandible. In the midline of the mandible, the distance between the submental artery and the lower margin of the mandible was (9.0±1.0) mm. In the midsagittal plane, the starting point of the submental artery was(8.4±1.0) mm from the lower margin of the mandible.Conclusions:There were several types of facial arteries and the courses were various, but the way they branched and the layers they coursed had certain rules. Understanding the anatomy of facial arteries is helpful to keep the treatment safe.

Objective:To investigate the clinical effect of reconstructed tragus with hinge-shaped cartilage flap during the third stage reconstructive surgery in patients with microtia.Methods:From January 2018 to January 2019, the data of the patients with unilateral microtia of residual ear Type Ⅲ treated in the Seventh Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences were analyzed retrospectively. The residual ear tissue preserved in the second stage operation was used to reconstruct the tragus during the third stage operation, and the external auditory meatus was simulated with medium-thickness skin grafting. Postoperative changes were observed in the width, height, and symmetry of the tragus.Results:A total of 31 children with microtia were included, including 19 males and 12 females, aged from 6 to 14 years (mean 8 years), right ear ( n=16) and left ear ( n=15). Postoperative blood supply was good, and the incisions healed primarily. The patient’s immediate postoperative tragus width and height were slightly greater than the preoperative design requirements. After follow-up of 3-6 months, the width of the contralateral tragus was (1.05±0.12) cm, while the reconstructed tragus width was (0.98±0.17) cm. The difference was not statistically significant ( P=0.328). The height of the contralateral tragus was (0.53±0.08) cm, while the reconstructed tragus width was (0.55±0.08) cm. The difference was not statistically significant ( P=0.741). The reconstructed tragus had a good three-dimensional structure and stable shape, and the simulated shape of the external auditory meatus was good. Patients can wear earphones to meet the needs of daily life. Conclusions:Using residual ear cartilage to reconstruct the tragus by flapping hinge-cartilage can improve the three-dimensional structure of the auricle and skin grafting to the concha cavity posterior to the tragus can simulate external auditory meatus. The reconstructed ear resembles the healthy one and meets the need of wearing earphones.

Objective:To investigate the clinical effect of auricle reconstruction using an expanded postauricular flap with double pedicle in the ear reconstruction.Methods:From September 2016 to August 2017, the clinical data of all patients with congenital microtia treated in the Department of Plastic Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences were analyzed retrospectively. The surgical procedures: The expander was implanted in the first stage. The ear framework was covered by the retroauricular double-pedicled expanded flap with free skin grafting at the retroauricular superior margin in the second stage, and the helix was wrapped by the retroauricular fascia. The patients were followed up at 1, 6 months after operation and before the third stage operation, and the appearance of the reconstructed auricle was evaluated by two junior doctors before the third stage of the operations. If there were any differences, the final evaluation would be carried out by a senior doctor. The evaluation results were good, medium and poor.Results:A total of 46 patients (49 ears) with congenital microtia were included, including 36 males (39 ears) and 10 females (10 ears), with the age range of 6-23 years. After operation, the blood supply was good, and the skin grafts survived completely. Three ears had postoperative hematomas under the double-pedicled expanded skin flap when the drainage was removed 5 days after operation. The hematomas recovered well after the negative pressure suction and dressing changed. During the follow-up of 6 months and 18 months, 43 cases (46 ears) were evaluated well with symmetrical and clear three-dimensional structure of reconstructed auricles, uniformed color, and hidden scar behind the ear. Three cases (3 ears) were evaluated as medium. There was hematoma when the drainage tube was removed 5 days after operation, which survived completely after negative suction and dressing change. No cartilage framework infection and exposure were found.Conclusions:The double-pedicled expanded flap has many advantages, such as reliable blood supply, natural auricle appearance, concealed scar, and less skin color difference. It is a good choice for soft tissue wrapping and covering during auricle reconstruction.

Objective:To design a real time dynamic three-dimensional(3D) auricular image guidance based on sensors and make an evaluation of it.Methods:One commercial head model and 3 volunteers (2 men and 1 woman, aged 24-27 years old) recruited from Plastic Surgery Hospital, Chinese Academy of Medical Sciences in August 2019 were studied. Digital models of auricle were made using CT data of three volunteers with ITK-SNAP 3.6.0 and MeshLab (V 2016.12.23). The optimal number of sensors was three and the optimal location of sensors was one side of the eyebrow, the nasal tip and the inferior point of the earlobe. The virtual model was connected with the real auricle based on three sensors. The 3D auricular image was projected to the corresponding real auricle through the projector. The infrared motion-capture device was used to capture the changes of the position of the sensors to realize real-time tracking. The matching accuracy between 3D auricular image and real auricle was evaluated by calculating the coincidence error rate after registration, calculating the coincidence error rate, image deformation and tracking latency during tracking.Results:The average coincidence error rate after registration was 2.5% (the difference between the normal bilateral ears was 2.7%), which showed the registration precision was high. The coincidence error rate was lower than 2.7% in certain rotation angle (30° clockwise) and the image deformation was lower than 2.6% in certain rotation angle (30° clockwise and 15° counterclockwise) during tracking, which demonstrated the precision of tracking head movement was high and image deformation was low in a certain rotation range. The time of image update and motion tracking was less than 0.1 s, which satisfied the requirement of surgery.Conclusions:This study demonstrates that the fabrication of real-time dynamic 3D auricular image guidance based on sensors is feasible and the image guidance has high accuracy of registration and tracking, low image deformation and fast tracking speed, which lays a foundation for its application in clinical auricle reconstruction in the future.

Objective:Facial artery is the main blood supply source of facial soft tissue, which has an important influence on facial plastic surgery and injection procedures. There are many types of facial arteries. They have wide coverage, and travel several layers. In this study, the detailed characteristics of the facial arteries were revealed by cadaver dissection.Methods:In 19 donated fresh cranial (28 sides) specimens, the facial arteries were dissected. And then the type, layer, relationship with nasolabial groove, length, diameter, distance from the oral commissure, branches and submental artery were observed and measured.Results:Facial arteries were found in all cadavers, starting from the external carotid arteries, branching submental arteries below the mandibular margins, ascending to the anterior edge of the masseter muscles, crossing the mandibles and entering the faces. After entering into the faces, the facial arteries branched the submental arteries(100%, 28/28), lower labial arteries (100%, 28/28), upper labial arteries (100%, 28/28), lateral nasal arteries (92.9%, 26/28) and the angular arteries (57.2%, 16/28) throughout the courses. According to the vascular route, the facial artery was classified into four types. In TypesⅠ(8 sides), all branches were included and the angular arteries arose directly from the lower segment of the facial arteries (28.6%). In TypesⅡ(8 sides), all branches were included and the angular arteries were the terminal branches (28.6%). In TypesⅢ(10 sides), angular arteries were absent (35.7%). In Type Ⅳ (2 sides), angular arteries and lateral nasal arteries were absent (7.1%). The lower segment of facial artery coursed under the facial expression muscles, and continued to the middle segment at the point which was (26.0±5.0) mm away from the oral commissure on the lateral side. The layer that the facial artery coursed was varied. It passed through the superficial layer of the facial expression muscles. After passing the horizontal line parallel to the lower margin of nasal sill, the upper segment continued to on the superficial layer of the facial expression muscles. The facial arteries were mostly located medial to the nasolabial fold(24 sides, 85.7%) and occasionally across the nasolabial fold(4 sides, 14.3%). The lengths of the upper, middle and lower segments of facial artery were (26.4±10.9) mm, (29.7±8.4) mm, and(33.5±6.9) mm, respectively. The diameters in starting point of upper, middle and lower sections were(2.45±0.48) mm, (1.85±0.12) mm, and (1.09±0.21) mm, respectively. The facial artery passed lateral to the oral commissure and the distance from the intersection of the horizontal line to the oral commissure was (26.0±5.0) mm. The starting point of the superior labial artery locacted below the horizontal line was (8.0±1.4)mm away from the horizontal line of the oral commissure and(55.0±5.2) mm from the mandibular angle. The starting point of the inferior labial artery located below the horizontal line was (17.1±11.1) mm from the horizontal line of the oral commissure, and the distance from the mandibular angle was (44.2±5.2) mm. The diameter of the submental artery in its starting point was (1.4±0.1) mm. The distance from the starting point of the submental artery to the horizontal line of the oral commissure was (34.9±2.6) mm, and the distance from the mandibular angle was (29.4±5.8) mm. The starting point of the submental artery was (6.4±0.8) mm from the lower margin of the mandible. In the midline of the mandible, the distance between the submental artery and the lower margin of the mandible was (9.0±1.0) mm. In the midsagittal plane, the starting point of the submental artery was(8.4±1.0) mm from the lower margin of the mandible.Conclusions:There were several types of facial arteries and the courses were various, but the way they branched and the layers they coursed had certain rules. Understanding the anatomy of facial arteries is helpful to keep the treatment safe.