Feasibility of a Robot-Assisted Surgical Navigation System for Mandibular Distraction Osteogenesis in Hemifacial Microsomia: A Model Experiment.

This study aimed to investigate the feasibility and accuracy of osteotomy and distractor placement using a robotic navigation system in a model surgical experiment of mandibular distraction osteogenesis for hemifacial microsomia. Imaging data from 5 patients with Pruzansky-Kaban type II (IIa: 4; IIb: 1) mandibular deformities were used to print 3D models for simulated mandibular distraction osteogenesis. In the experimental group, a robot-assisted surgical navigation system was used to perform the surgery under robotic guidance following registration, according to the preoperative design. Conventional surgery was performed in the control group, in which the operation was based on intraoperative estimations of the preoperative design by experienced surgeons. The accuracies of the osteotomy and distractor placement were assessed based on distance and angular error. Osteotomy accuracy was higher in the experimental group than in the control group, and the distance error ( t =9.311, P <0.001) and angular error ( t =5.385, P =0.001) were significantly reduced. The accuracy of distractor placement was also significantly higher in the experimental group, while the distance error ( t =3.048, P =0.016) and angular error ( t =3.524, P =0.024) were significantly reduced. The present results highlight the feasibility of robot-assisted distraction osteogenesis combined with electromagnetic navigation for improved surgical precision in clinical settings.

[Research on the Application of Electromagnetic Navigation Technology in Surgical Robots].

Due to the need to achieve precise operations during surgery, in order to prevent hand tremors and poor surgical field of view, more and more surgical robots are used in surgical operations combined with navigation technology to meet the requirements for surgical accuracy. Open surgery such as orthopaedics, joint replacement and neurosurgery on the market generally use optical navigation systems to guide robots to achieve precise positioning, but optical navigation systems cannot be used for operations in areas with small surgical space. Therefore, a robotic surgical system based on electromagnetic navigation technology that can be applied to the craniofacial area was proposed. By using this robot, the problems of difficult operation and low precision caused by the narrow craniofacial space can be solved. Key techniques and considerations are studied. The function of the developed prototype is verified through model tests. The test results show that the surgical robot under the electromagnetic navigation technology can achieve precise surgical operations improve the success rate of the doctor's surgery and reduce postoperative complications.

Robot-Assisted Surgery for Mandibular Angle Split Osteotomy Using Augmented Reality: Preliminary Results on Clinical Animal Experiment.

Mandibular angle split osteotomy (MASO) is a procedure widely used for prominent mandibular angles. However, conventional mandibular plastic surgery is invasive and high risk. It may induce postoperative neurosensory disturbance of the inferior alveolar nerve, fractures and infection due to the complexity of the anatomical structure and the narrow surgical field of view. The success rate of MASO surgery usually depends on the clinical experience and skills of the surgeon. To evaluate the performance of inexperienced plastic surgeons conducting this surgery, a self-developed and constructed robot system based on augmented reality is used. This robot system provides for sufficient accuracy and safety within the clinical environment. To evaluate the accuracy and safety of MASO surgery, an animal study using this robot was performed in the clinical room, and the results were then evaluated. Four osteotomy planes were successfully performed on two dogs; that is, twenty tunnels (each dog drilled on bilaterally) were drilled in the dogs' mandible bones. Errors at entrance and target points were 1.04 ± 0.19 and 1.22 ± 0.24 mm, respectively. The angular error between the planned and drilled tunnels was 6.69° ± 1.05°. None of the dogs experienced severe complications. Therefore, this technique can be regarded as a useful approach for training inexperienced plastic surgeons on the various aspects of plastic surgery. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A study of an assisting robot for mandible plastic surgery based on augmented reality.

BACKGROUND: Mandible plastic surgery plays an important role in conventional plastic surgery. However, its success depends on the experience of the surgeons. In order to improve the effectiveness of the surgery and release the burden of surgeons, a mandible plastic surgery assisting robot, based on an augmented reality technique, was developed. MATERIAL AND METHODS: Augmented reality assists surgeons to realize positioning. Fuzzy control theory was used for the control of the motor. During the process of bone drilling, both the drill bit position and the force were measured by a force sensor which was used to estimate the position of the drilling procedure. RESULTS: An animal experiment was performed to verify the effectiveness of the robotic system. The position error was 1.07 ± 0.27 mm and the angle error was 5.59 ± 3.15°. The results show that the system provides a sufficient accuracy with which a precise drilling procedure can be performed. In addition, under the supervision's feedback of the sensor, an adequate safety level can be achieved for the robotic system. CONCLUSION: The system realizes accurate positioning and automatic drilling to solve the problems encountered in the drilling procedure, providing a method for future plastic surgery.

Design and static calibration of a six-dimensional force/torque sensor for minimally invasive surgery.

INTRODUCTION: The use of surgery robotics is getting more and more important worldwide. In the present study, we propose a novel small-size six-dimensional force/torque sensor with the structure of double cross beams. This technology can be applied in robotic tele-operation systems used in minimally invasive surgery (MIS) robotic systems. MATERIAL AND METHODS: The proposed sensor is made of duralumin which totally meets the stiffness requirement. The output voltage of the sensor will alter with the deformation of the elastic body and strain gauges. The feasibility was discussed by finite element analysis (FEA) and the coupling coefficient matrix was established with dimension reduced according to FEA. In addition, we designed a calibration platform and completed static calibration for the sensor. The methods and principles of measurements and data analysis were provided. RESULTS: The calibration curves and coupling coefficient matrix were acquired by using the least squares method (LSM). CONCLUSION: Experimental tests and calibration error analysis showed that the proposed sensor has high accuracy, appropriate range, and played a role in promoting the application of force feedback technology in MIS.

Comparative transcriptome analysis reveals the resistance regulation mechanism and fungicidal activity of the fungicide phenamacril in Fusarium oxysporum.

Fusarium oxysporum (Fo) is an important species complex of soil-borne pathogenic fungi that cause vascular wilt diseases of agricultural crops and some opportunistic diseases of humans. The fungicide phenamacril has been extensively reported to have antifungal activity against Fusarium graminearum and Fusarium fujikuroi. In this study, we found that the amino acid substitutions (V151A and S418T) in Type I myosin FoMyo5 cause natural low resistance to phenamacril in the plant pathogenic Fo isolates. Therefore, we compared the transcriptomes of two phenamacril-resistant Fo isolates FoII5, Fo1st and one phenamacril-sensitive isolate Fo3_a after 1 µg/mL phenamacril treatment. Among the 2728 differentially expressed genes (DEGs), 14 DEGs involved in oxidation-reduction processes and MFS transporters, were significantly up-regulated in phenamacril-resistant isolates. On the other hand, 14 DEGs involved in ATP-dependent RNA helicase and ribosomal biogenesis related proteins, showed significantly down-regulated expression in both phenamacril-resistant and -sensitive isolates. These results indicated that phenamacril not only seriously affected the cytoskeletal protein binding and ATPase activity of sensitive isolate, but also suppressed ribosome biogenesis in all the isolates. Hence, this study helps us better understand resistance regulation mechanism and fungicidal activity of phenamacril and provide reference for the development of new fungicides to control Fo.

Guard cell anion channel PbrSLAC1 regulates stomatal closure through PbrSnRK2.3 protein kinases.

Stomatal pores on the leaf surface are the gateways for gas exchange between plants and the atmosphere, which is regulated mainly by the S-type anion channel SLAC1. However, the gene encoding the main S-type anion channel SLAC1 in pear and its genetic characteristics remain unknown. In this study, Pbr015894.1 was identified as the candidate for PbrSLAC1 in pear, and it was found to be expressed abundantly in leaves, particularly in the guard cells. Virus-induced gene silencing experiments indicated that stomatal closure was achieved by a change in cell turgor instigated by PbrSLAC1 channel transport of NO3- in pear leaves and induced by abscisic acid. Furthermore, the expression of PbrSLAC1 in Arabidopsis slac1-3 and slac1-4 rescued the defective NO3- transport seen in these mutants, pointing to its role in anion transport. Fluorescence microscopy suggested that PbrSLAC1 was localized in the plasma membrane, and a dual-luciferase assay system demonstrated an interaction between PbrSLAC1 and PbrSnRK2.3/2.8. Moreover, anion conductance mediated by PbrSLAC1 was activated by PbrSnRK2.3 in Xenopus laevis oocytes and the channel showed greater permeability for nitrate than chloride, sulfate, or malate ions. Taken together, these results demonstrate that PbrSLAC1, an anion channel regulated by PbrSnRK2.3, is involved in stomatal closure by mediating the efflux of NO3- in pear leaf.

Preliminary clinical experience of robot-assisted surgery in treatment with genioplasty.

Genioplasty is the main way to treat diseases such as chin asymmetry, dysplasia and overdevelopment, which involve the three-dimensional direction abnormalities of the chin. Since this kind of surgery mainly uses intraoral incisions, the narrow surgical field of intraoral incisions and the surrounding important neurovascular tissues make it easy for complications, to occur during the osteotomy process, which results in greater surgical risks. The first craniofacial-plastic surgical robot (CPSR-I) system is developed to complete the precise positioning and improve the surgeon's force perception ability. The Kalman filtering method is adopted to reduce the interference of sensor signal noise. An adaptive fuzzy control system, which has strong robustness and adaptability to the environment, is designed to improve the stability of robot-assisted surgical operations. To solve the problem of the depth perception, we propose an automatic bone drilling control strategy that combines position and force conditions to ensure that the robot can automatically stop when the bone is penetrated. On the basis of model surgery and animal experiments, preliminary experiments were carried out clinically. Based on the early results of 6 patients, the robot-assisted approach appears to be a safe and effective strategy for genioplasty.

Generation of a Movement Scheme for Positive Training.

Rehabilitation robots have been demonstrated to be an efficient tool in the field of rehabilitation training. Meanwhile, there are varieties of tasks designed for motion training. These tasks need to be transmitted to motion data for rehabilitation robots. In this paper, we designed a drinking task and captured the motion data as the ground truth, through sensors of an exoskeleton device named Neo-Arm. To verify the effectiveness of Neo-Arm, we used a Vicon system to capture the same motion task without Neo-Arm for comparison. Eight subjects participated in the experiment. The motion data of the drinking task, including the range of motion (ROM) and the velocity of each joint, are obtained. The result shows that the Neo-Arm can achieve the suitable precision and be fit for other kinds of upper limb motion tasks.

Research of the master-slave robot surgical system with the function of force feedback.

BACKGROUND: Surgical robots lack force feedback, which may lead to operation errors. In order to improve surgical outcomes, this research developed a new master-slave surgical robot, which was designed with an integrated force sensor. METHODS: The new structure designed for the master-slave robot employs a force feedback mechanism. A six-dimensional force sensor was mounted on the tip of the slave robot's actuator. Sliding model control was adopted to control the slave robot. According to the movement of the master system manipulated by the surgeon, the slave's movement and the force feedback function were validated. RESULTS: The motion was completed, the standard deviation was calculated, and the force data were detected. Hence, force feedback was realized in the experiment. CONCLUSIONS: The surgical robot can help surgeons to complete trajectory motions with haptic sensation.

Mandibular angle split osteotomy based on a novel augmented reality navigation using specialized robot-assisted arms--A feasibility study.

PURPOSE: Augmented reality (AR) navigation, is a visible 3-dimensional display technology, that, when combined with robot-assisted surgery (RAS), allows precision and automation in operational procedures. In this study, we used an innovative, minimally invasive, simplified operative method to position the landmarks and specialized robot-assisted arms to apply in a rapid protyping (RP) model. This is the first report of the use of AR and RAS technology in craniomaxillofacial surgery. METHOD: Five patients with prominent mandibular angle were randomly chosen for this feasibility study. We reconstructed the mandibular modules and created preoperational plans as semi-embedded and nail-fixation modules for an easy registration procedure. The left side of the mandibular modules comprised the experimental groups with use of a robot, and the right sides comprised the control groups without a robot. With AR Toolkits program tracking and display system applied, we carried out the operative plans and measured the error. RESULTS: Both groups were successfully treated in this study, but the RAS was more accurate and stable. The average position and angle were significant (p < 0.01) between the 2 groups. CONCLUSIONS: This study reports a novel augmented reality navigation with specialized robot-assisted arms for mandibular angle split osteotomy. AR and RAS can be helpful for patients undergoing craniomaxillofacial surgery.