Effect of navigation endoscopy combined with threedimensional printing technology in the treatment of orbital blowout fractures

●AIM:To explore the combined application of surgical navigation nasal endoscopy(NNE)and three-dimensional printing technology(3DPT)for the adjunctive treatment of orbital blowout fractures(OBF).●METHODS:Retrospective analysis was conducted on the data of patients with OBF who underwent surgical treatment at the Affiliated Eye Hospital of Nanchang University between July 2012 and November 2022.The control group consisted of patients who received traditional surgical treatment(n=43),while the new surgical group(n=52)consisted of patients who received NNE with 3DPT.The difference in therapeutic effects between the two groups was evaluated by comparing the duration of the operation,best corrected visual acuity(BCVA),enophthalmos difference,recovery rate of eye movement disorder,recovery rate of diplopia,and incidence of postoperative complications.●RESULTS:The study included 95 cases(95 eyes),with 63 men and 32 women.The patients’age ranged from 5 to 67y(35.21±15.75y).The new surgical group and the control group exhibited no statistically significant differences in the duration of the operation,BCVA and enophthalmos difference.The recovery rates of diplopia in the new surgical group were significantly higher than those in the control group at 1mo[OR=0.03,95%CI(0.01–0.15),P<0.0000]and 3mo[OR=0.11,95%CI(0.03–0.36),P<0.0000]postoperation.Additionally,the recovery rates of eye movement disorders at 1 and 3mo after surgery were OR=0.08,95%CI(0.03–0.24),P<0.0000;and OR=0.01,95%CI(0.00–0.18),P<0.0000.The incidence of postoperative complications was lower in the new surgical group compared to the control group[OR=4.86,95%CI(0.95–24.78),P<0.05].●CONCLUSION:The combination of NNE and 3DPT can shorten the recovery time of diplopia and eye movement disorder in patients with OBF.

Current trends in three-dimensional visualization and real-time navigation as well as robot-assisted technologies in hepatobiliary surgery

With the continuous development of digital medicine,minimally invasive precision and safety have become the primary development trends in hepatobiliary surgery.Due to the specificity and complexity of hepatobiliary surgery,traditional preoperative imaging techniques such as computed tomography and magnetic resonance imaging cannot meet the need for identification of fine anatomical regions.Imaging-based three-dimensional(3D)reconstruction,virtual simulation of surgery and 3D printing optimize the surgical plan through preoperative assessment,improving the controllability and safety of intraoperative operations,and in difficult-to-reach areas of the posterior and superior liver,assistive robots reproduce the surgeon’s natural movements with stable cameras,reducing natural vibrations.Electromagnetic navigation in abdominal surgery solves the problem of conventional surgery still relying on direct visual observation or preoperative image assessment.We summarize and compare these recent trends in digital medical solutions for the future development and refinement of digital medicine in hepatobiliary surgery.

Analysis and Design of Surgical Instrument Localization Algorithm

With the help of surgical navigation system,doctors can operate on patients more intuitively and accurately.The positioning accuracy and real-time performance of surgical instruments are very important to the whole system.In this paper,we analyze and design the detection algorithm of surgical instrument location mark,and estimate the posture of surgical instrument.In addition,we optimized the pose by remapping.Finally,the algorithm of location mark detection proposed in this paper and the posture analysis data of surgical instruments are verified and analyzed through experiments.The final result shows a high accuracy.

New Method of Reconstruction from Nonparallel Stereo and Application to Surgical Navigator

A new method to reconstruct 3D scene points from nonparallel stereo is proposed. From a pair of conjugate images in an arbitrarily configured stereo system that has been calibrated, coordinates of 3D scene points can be computed directly using the method, bypassing the process of rectifying images or iterative solution involved in existing methods. Experiment results from both simulated data and real images validate the method. Practical application to surgical navigator shows that the method has advantages to improve efficiency and accuracy of 3D reconstruction from nonparallel stereo system in comparison with the conventional method that employs algorithm for standard parallel axes stereo geometry.

Real-time virtual sonography visualization and its clinical application in biliopancreatic disease

AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasound image in real time by merging the ultrasound image with a multiplanar reconstruction computed tomography(CT)image,using pre-scanned CT volume data.The ultrasound used was EUB-8500with a convex probe EUP-C514.The RVS images were evaluated based on 3 levels,namely,excellent,good and poor,by the displacement in position.RESULTS:By combining the objectivity of CT with free scanning using RVS,it was possible to easily interpret the relationship between lesions and the surrounding organs as well as the position of vascular structures.The resulting evaluation levels of the RVS images were12 excellent(pancreatic cancer,bile duct cancer,cholecystolithiasis and cholangiocellular carcinoma)and 3 good(pancreatic cancer and gallbladder cancer).Compared with conventional B-mode ultrasonography and CT,RVS images achieved a rate of 80%superior visualization and 20%better visualization.CONCLUSION:RVS has potential usefulness in objective visualization and diagnosis in the field of biliary and pancreatic diseases.

Precise Point Positioning Technique with IGS Real-Time Service (RTS) for Maritime Applications

The maritime navigation accuracy requirements for radionavigation systems such as GPS are specified by the International Maritime Organization (IMO). Maritime navigation usually consists of three major phases identified as Ocean/Coastal/Port approach/Inland waterway, in port navigation and automatic docking with an accuracy requirement that ranges from 10 m to 0.1 m. With the advancement in autonomous GPS positioning techniques such as Precise Point Positioning (PPP) and with the advent of the new IGS-Real-Time-Service (RTS), it is necessary to assess the possibility of a wider role of the PPP-based positioning technique in maritime applications. This paper investigates the performance of an autonomous real-time PPP-positioning solution by using the IGS- RTS service for maritime applications that require an accurate positioning system. To examine the performance of the real-time IGS-RTS PPP-based technique for maritime applications, kinematic data from a dual frequency GPS receiver is investigated. It is shown that the real-time IGS-RTS PPP-based GPS positioning technique fulfills IMO requirements for maritime applications with an accuracy requirement ranges from 10 m for Ocean/Coastal/Port approach/Inland waterways navigation to 1.0 m for in port navigation but cannot fulfill the automatic docking application with an accuracy requirement of 0.10 m. To further investigate the real-time PPP-based GPS positioning technique, a comparison is made between the real-time IGS-RTS PPP-based positioning technique and the real-time PPP-based positioning by using the predicted part of the IGS Ultra-Rapid products and the real-time GPS positioning technique with the Wide Area Differential GPS service (WADGPS). It is shown that the IGS-RTS PPP-based positioning technique is superior to the IGS-Ultra-Rapid PPP-based and WADGPS-based positioning techniques.

RRVPE:A Robust and Real-Time Visual-Inertial-GNSS Pose Estimator for Aerial Robot Navigation

Self-localization and orientation estimation are the essential capabilities for mobile robot navigation.In this article,a robust and real-time visual-inertial-GNSS(Global Navigation Satellite System)tightly coupled pose estimation(RRVPE)method for aerial robot navigation is presented.The aerial robot carries a front-facing stereo camera for self-localization and an RGB-D camera to generate 3D voxel map.Ulteriorly,a GNSS receiver is used to continuously provide pseudorange,Doppler frequency shift and universal time coordinated(UTC)pulse signals to the pose estimator.The proposed system leverages the Kanade Lucas algorithm to track Shi-Tomasi features in each video frame,and the local factor graph solution process is bounded in a circumscribed container,which can immensely abandon the computational complexity in nonlinear optimization procedure.The proposed robot pose estimator can achieve camera-rate(30 Hz)performance on the aerial robot companion computer.We thoroughly experimented the RRVPE system in both simulated and practical circumstances,and the results demonstrate dramatic advantages over the state-of-the-art robot pose estimators.

Nanomaterials for visualized tumor surgical navigation and postoperative recurrence inhibition

Preoperative localization of the tumor sites and intraoperative real-time monitoring are essential for precise surgery but are meanwhile challenging due to the lack of high-resolution,easy-to-operate,and fast visualization techniques.On the other hand,tumor recurrence and metastasis after surgery greatly reduce the survival rate of patients.Intervening tumor recurrence during surgery is a future direction of tumor treatment.Nanomaterials with external condition responsiveness(light,ultrasound,and magnetic field)can accurately assist intraoperative detection and surgical resection due to their functions such as tumor cell targeting,fluorescence imaging,and real time monitoring,providing a more accurate,shorter duration,and visualization method of surgical resection.Moreover,nanomaterials are versatile and can easily be tailored for application in different tumors.Locally filled or systemically circulating nanomaterials with slow drug release and residual tumor cell-targeting ability have promising applications in inhibiting tumor recurrence.Here,we review surgical navigation and postoperative recurrence interventional nanomaterials and their landscape in guiding tumor treatment.We summarize the classification and characteristics of these nanomaterials and discuss their application in the surgical navigation and recurrence inhibition of different tumors.We also provide an outlook on the challenges and future development of nanomaterials for visualized tumor surgical navigation and postoperative recurrence inhibition.

混合现实技术在口腔颌面部肿瘤诊疗中的应用

口腔颌面部肿瘤是口腔颌面外科的常见疾病,以虚拟手术设计、手术导航为代表的数字化外科技术目前已成为口腔颌面部肿瘤外科诊治的主要辅助手段。然而,现有的数字化技术在三维可视化成像、术中手眼配合等方面仍存在提升空间。目前,以混合现实技术为代表的三维可视化技术已经在医学领域迅速发展和应用,通过将三维虚拟图像叠加到真实的手术环境中,可辅助实现医学影像实时立体呈现,已逐步应用于口腔颌面部肿瘤的诊治中。术前可基于影像数据构建肿瘤及其周边重要结构三维模型,在混合现实环境中,进行个性化术前评估和手术方案设计;术中将混合现实技术与手术导航技术相结合,可以在术区真实环境中实时显示三维虚拟模型,克服单纯使用导航技术的手眼协调问题,进一步提高口腔颌面部肿瘤手术的精确性和安全性。混合现实技术与远程互联网医疗技术相结合,还可以提供高质量的教学平台,推动地区口腔颌面外科诊疗水平的发展。混合现实技术的局限性主要在于术区影像遮挡、单纯使用时精度不足、配准时间长等。笔者结合国内外文献报道以及本课题组的临床实践,对混合现实技术在口腔颌面部肿瘤诊疗中的应用进行归纳与总结。

屈光性白内障手术质效优化技术现状与进展

当前白内障手术已经进入屈光性白内障手术时代,精准控制目标屈光度,快速有效提高患者的视觉质量成为白内障医生的共同追求。而飞秒激光辅助的白内障手术、手术导航技术、主动控制液流超声乳化技术、专用的高质量眼内灌注液、无滴眼液手术模式、眼表修复与干眼管理、功能型人工晶状体的应用、术后视功能训练等手术质效优化方面,可以进一步提升患者诊疗体验、加速患者康复、提升术后视觉质量、提升患者满意度等,促进屈光白内障手术发展。

计算机辅助口腔种植手术的临床应用进展

为了提高种植体的植入精度,减轻手术创伤,提高种植治疗的成功率和美学效果,计算机辅助技术被应用于种植手术。计算机辅助的种植手术主要分为两类:静态计算机辅助种植手术与动态计算机辅助种植手术。其中,静态计算机辅助种植手术通过术前设计制作的手术导板引导术者植入种植体;而动态计算机辅助种植手术通过实时定位与追踪技术引导术者,其操作高效、快捷,具有广阔的应用前景。近年来,得益于数字化技术的快速发展,计算机辅助口腔种植手术在临床实践中得到了越来越广泛的应用。本文对计算机辅助口腔种植手术的分类和临床流程、种植体植入精度和影响植入精度的因素、临床效果和患者报告指标进行详细论述。

寰枢椎脱位手术中置钉技术应用进展

近年来,伴随着科学技术的进步,在寰枢椎脱位的手术中置钉的技术也在不断发展。本文整理了寰枢椎脱位近十年常用的重要置钉技术,分为徒手置钉技术和新型机器人置钉技术,并介绍了徒手置钉技术及机器人置钉技术的置钉原理及常用设备,分别阐述其优缺点,最后进行整理比较和总结归纳,并提出目前临床及研究领域置钉技术所面临的局限,以促进置钉技术的未来发展。

可见-近红外二区双通道荧光成像系统

本文基于光学手段,开发出了一套能够兼顾可见光与近红外二区(NIR-Ⅱ)窗口的双通道宏观成像系统,能够实时输出具有NIR-Ⅱ荧光信息的高质量明场图像,解决了常规的NIR-Ⅱ宏观成像系统提供的荧光图像与明场图像割裂较大的问题。实验中利用不同厚度的脂肪组织测试了吲哚菁绿的NIR-Ⅱ窗口荧光信号分别在1 100~1 700 nm长通滤光片与1 300~1 700 nm长通滤光片下的抗散射能力与成像表现。接着利用所搭建的双通道宏观成像系统分别在小鼠以及大鼠模型上实现了淋巴结成像并模拟进行了淋巴结的切除手术,模拟了对腹腔淋巴结清扫的过程。最后,在大鼠模型上添加了不同厚度的生物脂肪组织,模拟实际手术中脂肪组织覆盖在淋巴结上的情况,观察双通道系统的穿透能力。可见近红外二区双通道荧光成像系统通过给操作者提供直观的影像信息,缩减手术时间、提高患者的预后,在临床手术导航中具有较大的应用潜力。

基于柔顺控制的智能神经导航手术机器人系统设计

机器人辅助微创手术,因其低侵袭性而变得越来越普遍。然而,因定向障碍和缺乏导航信息限制了其在经自然腔道手术的进一步应用。自然腔道解剖结构复杂,机器人末端的手术器械易损伤周围血管和神经。本研究设计了一种智能控制导航手术机器人系统,使用可靠和安全的定位技术、7自由度机械臂以及避免关节角度限制的逆运动学控制策略,以实现高灵活度的机械臂控制。基于患者术前影像进行手术导航与手术规划,并通过阻抗柔顺控制将患者与手术器械的接触力限制在一定范围内,实现保护患者的正常组织。为了提高手术精度并缓解医生的手术强度,智能语音控制实现术中手术器械位置和姿态的微小调整。基于体模和尸头实验进行系统的有效性验证。结果显示,本系统的定位误差小于1 mm,轨迹追踪角度误差小于2.5°,术中导航可进行实时手术靶点与器械跟踪,阻抗柔顺控制可将手术器械与患者之间的接触力降低在1.2 N以下,基于语音识别的精细调控可以满足术中对手术器械运动控制的要求。本研究的结果初步表明,所设计的手术机器人系统在机器人辅助微创手术中具有潜在的应用前景。

计算机辅助在关节镜手术诊疗中的应用进展

关节镜是一种临床常用的微创检查和治疗方法,但其视野易受关节内组织遮挡,常需要配合其他影像检查应用。随着医疗设备及计算机图像处理技术的不断发展,基于计算机辅助的手术方式在普外科、骨科等的应用已相对成熟,能在术中提供精确的导航。因此,基于计算机辅助的手术方式在关节镜外科手术中的应用逐渐受到重视。本研究对计算机辅助骨科手术的原理和技术进行分析,从术前成像、术中导航、机械臂操作等方面分析计算机辅助关节镜手术的诊疗应用进展以及技术可行性,发掘其潜在的临床应用价值,讨论存在的问题,进一步提升我国关节镜手术诊疗可行性。

基于主动光源阵列的骨科机器人末端示踪装置

为减少机械臂导航过程中示踪装置视线遮挡问题对手术的影响,研究一种多角度主动光源阵列的末端示踪装置,采用非支架式的机械结构,配合双目相机,实现对手术机械臂位置的感知。通过大小两个棱柱相互配合,组成多角度的光源阵列,实现对机械臂工具中心点的计算。通过COMSOL软件搭建简易模型,验证示踪装置信号使用范围;通过覆盖范围实验和静态定位实验证明装置的有效性和稳定性,可以满足手术机器人的任务要求。

一种基于结构光的高效手术导航空间注册方法

空间注册是手术导航系统获得手术空间与图像空间转换关系的关键步骤。针对现有手术导航系统存在的空间注册过程操作复杂、耗时长问题,本研究提出了一种基于编码散斑结构光的空间注册方法,设计了一种包含不同半径的圆形点阵光斑的散斑模板用于重建手术空间点云,通过与图像空间进行由粗到精的点云配准完成空间注册。实验表明,该方法在提升整体注册效率的同时,保证了较高的空间注册精度,整体注册时间小于10 s,所有靶点的平均注册精度为(0.89±0.08) mm,可满足在手术导航中的应用要求。

Navigated liver surgery:State of the art and future perspectives

Background:In recent years,the development of digital imaging technology has had a significant influence in liver surgery.The ability to obtain a 3-dimensional(3D)visualization of the liver anatomy has provided surgery with virtual reality of simulation 3D computer models,3D printing models and more recently holograms and augmented reality(when virtual reality knowledge is superimposed onto reality).In addition,the utilization of real-time fluorescent imaging techniques based on indocyanine green(ICG)uptake allows clinicians to precisely delineate the liver anatomy and/or tumors within the parenchyma,applying the knowledge obtained preoperatively through digital imaging.The combination of both has transformed the abstract thinking until now based on 2D imaging into a 3D preoperative conception(virtual reality),enhanced with real-time visualization of the fluorescent liver structures,effectively facilitating intraoperative navigated liver surgery(augmented reality).Data sources:A literature search was performed from inception until January 2021 in MEDLINE(Pub Med),Embase,Cochrane library and database for systematic reviews(CDSR),Google Scholar,and National Institute for Health and Clinical Excellence(NICE)databases.Results:Fifty-one pertinent articles were retrieved and included.The different types of digital imaging technologies and the real-time navigated liver surgery were estimated and compared.Conclusions:ICG fluorescent imaging techniques can contribute essentially to the real-time definition of liver segments;as a result,precise hepatic resection can be guided by the presence of fluorescence.Furthermore,3D models can help essentially to further advancing of precision in hepatic surgery by permitting estimation of liver volume and functional liver remnant,delineation of resection lines along the liver segments and evaluation of tumor margins.In liver transplantation and especially in living donor liver transplantation(LDLT),3D printed models of the donor’s liver and models of the recipient’s hilar anatomy can contribute further to improving the results.In particular,pediatric LDLT abdominal cavity models can help to manage the largest challenge of this procedure,namely large-for-size syndrome.

A retrospective study to compare the treatment outcomes with and without surgical navigation for fracture of the orbital wall

Purpose To evaluate the outcomes with and without aid of a computer-assisted surgical navigation system(CASNS)for treatment of unilateral orbital wall fracture(OWF).Methods Patients who came to our hospital for repairing unilateral traumatic OWF from 2014 to 2017 were included in this study.The patients were divided into the navigation group who accepted orbital wall reconstruction aided by CASNS and the conventional group.We evaluated the surgical precision in the navigation group by analyzing the difference between actual postoperative computed tomography data and preoperative virtual surgical plan through color order ratios.We also compared the duration of surgery,enophthalmos correction,restoration of orbital volumes,and improvement of clinical symptoms in both groups systemically.Quantitative data were presented as mean±SD.Significance was determined by the two-sample t-test using SPSS Version 19.0 A p<0.05 was considered statistically significant.Results Seventy patients with unilateral OWF were included in the study cohort.The mean difference between preoperative virtual planning and actual reconstruction outcome was(0.869±0.472)mm,which means the reconstruction result could match the navigation planning accurately.The mean duration of surgery in the navigation group was shorter than it is in the control group,but not significantly.Discrepancies between the reconstructed and unaffected orbital-cavity volume and eyeball projection in the navigation group were significantly less than that in the conventional group.One patient had remnant diplopia and two patients had enophthalmos after surgery in the navigation group;two patients had postoperative diplopia and four patients had postoperative enophthalmos in the conventional group.Conclusion Compare with the conventional treatment for OWF,the use of CASNS can provide a significantly better surgical precision,greater improvements in orbital-cavity volume and eyeball projection,and better clinical results,without increasing the duration of surgery.

基于HoloLens的增强现实手术导航系统精准融合显示方法

传统手术导航系统中医生需要频繁切换视野,存在手眼协同问题,且无法实时获取患者病灶区域的全局视野。近年来Holo-Lens被逐步应用于新兴的增强现实手术导航系统中,但是现有的HoloLens全息空间标定方法多数依赖于用户的主观感受,显示过程中也没有考虑用户行为和周围环境变化带来的误差。对此,提出了一种基于HoloLens的增强现实手术导航系统精准融合显示方法。使用双目相机和视觉标记物完成对现实空间中目标物体的实时追踪。基于手眼标定原理提出了一种稳定的HoloLens离线标定方法,通过多次采集HoloLens全息空间和现实空间中的坐标系转换关系,可以准确求解全息空间与现实空间之间的映射关系。建立融合显示过程的位姿矩阵传递关系后,用户可以快速地进行在线校正,实现虚拟影像与患者病灶区域的精准融合显示。Holo-Lens离线标定过程的平均耗时为4 min,用户在线校正的平均耗时为6.0 s。多个志愿者穿戴HoloLens设备进行融合显示精度验证实验,实验结果表明,校正前HoloLens融合显示的平均角度误差和平均距离误差分别为1.01°和3.95 mm,校正后融合显示的平均距离误差为1.46 mm。所提出的增强现实手术导航系统精准融合显示方法可以准确地标定HoloLens全息空间,经过用户在线校正后可以将虚拟影像与患者病灶区域融合显示,为医生提供准确完整的手术指导信息。实验结果表明该融合显示方法基本满足手术导航系统的精度和时间要求,具有临床应用的潜力。