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3D Hyperspectral Light-Field Imaging: a first intraoperative implementation 3D高光谱光场成像:术中首次应用
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1153
Eric L. Wisotzky, Peter Eisert, Anna Hilsmann
Abstract Hyperspectral imaging is an emerging technology that has gained significant attention in the medical field due to its ability to provide precise and accurate imaging of biological tissues. The current methods of hyperspectral imaging, such as filter-wheel, snapshot, line-scanning, and push-broom cameras have limitations such as low spatial and spectral resolution, slow acquisition time. New developments on the field of light field cameras show the potential to overcome these limitations. In this paper, we use a novel hyperspectral lightfield camera and try to combine the capability of hyperspectral and 3D analysis. For this purpose we calibrate our system and test it during two ENT-surgeries to show its potential for improving surgical outcomes. The micro-lenses of the camera map 66 spectral sub-images onto the sensor allowing to reconstruct the spectral behavior of the captured scene in the spectral range of 350-1000nm. In addition, we use the sensor data to apply a 3D camera calibration pipeline to allow 3D surface reconstruction. We captured 26 calibration images and achieved calibration results in accordance to stated company data. The best calibration showed a re-projection error of 0.55 px. Further, we tested the camera during a parotidectomy and a neck-dissection. The extracted reflectance spectra of the selected venal and arterial regions correspond perfectly to the spectrum of oxygenated and deoxygenated hemoglobin. For the first time, up to our knowledge, a hyperspectral lightfield camera has been used during a surgery. We were able to continuously capture images and analyze the reconstructed spectra of specific tissue types. Further, we are able to use the sensor data of the micro-lens projections to calibrate the multilens camera system for later intraoperative measurement tasks.
高光谱成像是一项新兴技术,由于其能够提供精确和准确的生物组织成像,在医学领域受到了极大的关注。目前的高光谱成像方法,如滤波轮、快照、行扫描和推扫帚相机等,存在空间和光谱分辨率低、采集时间慢等局限性。光场相机领域的新发展显示了克服这些限制的潜力。本文采用了一种新型的高光谱光场相机,并尝试将高光谱与三维分析相结合。为此,我们校准了我们的系统,并在两次ent手术中对其进行了测试,以显示其改善手术结果的潜力。相机的微镜头将66个光谱子图像映射到传感器上,从而可以在350-1000nm的光谱范围内重建捕获场景的光谱行为。此外,我们使用传感器数据应用3D相机校准管道,以允许3D表面重建。我们捕获了26张校准图像,并根据所述公司数据获得了校准结果。最佳校准显示重投影误差为0.55 px。此外,我们在腮腺切除术和颈部清扫术中测试了相机。所提取的静脉和动脉区域的反射光谱与氧合血红蛋白和脱氧血红蛋白的光谱完全对应。据我们所知,这是第一次在手术中使用高光谱光场相机。我们能够连续捕获图像并分析特定组织类型的重建光谱。此外,我们能够使用微透镜投影的传感器数据来校准多透镜相机系统,以用于后期的术中测量任务。
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引用次数: 0
Smartphone-Based Videonystagmography Using Artificial Intelligence 使用人工智能的基于智能手机的视频震动成像
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1132
Sophia Reinhardt, Joshua Schmidt, Jonas Schneider, Michael Leuschel, Elena Schulte, Christiane Schüle, Jörg Schipper
Abstract Dizziness is a common symptom in medicine. The anamnesis and detection of a nystagmus is essential to distinguish a vertigo's pathogenesis. The diagnosis is complex, expensive, and not always available across the board. We present a novel location- and time-independent mobile application for videonystagmography (VNG) to support vertigo patients and medical staff. No additional hardware is necessary. The app uses artificial intelligence for eye tracking and to detect a horizontal nystagmus. A feasibility study of the mobile VNG with 13 healthy volunteers was performed. Each participant underwent a caloric vestibular testing to provoke the presence of a vestibular nystagmus. It could be shown that a smartphone-based VNG is possible.
头晕是医学上常见的症状。眼球震颤的记忆和检测对于区分眩晕的发病机制至关重要。诊断是复杂的,昂贵的,而且并不总是全面可用。我们提出了一个新的位置和时间无关的移动应用程序,用于视频震动图(VNG),以支持眩晕患者和医务人员。不需要额外的硬件。该应用程序使用人工智能进行眼球追踪,并检测水平眼球震颤。对13名健康志愿者进行了移动VNG的可行性研究。每个参与者都进行了前庭热量测试,以诱发前庭眼球震颤。这可能表明,基于智能手机的VNG是可能的。
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引用次数: 0
Reduction of Uncertainty in Bolus Transit Time Measurement in Quantitative Fluorescence Angiography 定量荧光血管造影中丸传递时间测量不确定度的降低
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1155
Yang Gao, Miriam Weiß, Werner Nahm
Abstract During cerebral revascularization surgeries, blood flow values help surgeons to monitor the quality of the procedure, e.g., to avoid cerebral hyperperfusion syndrome due to excessively enhanced perfusion. The state-of-the-art technique is the ultrasonic flow probe that has to be placed around the blood vessel. This causes contact between probe and vessel, which, in the worst case, leads to rupture. The recently developed intraoperative indocyanine green (ICG) Quantitative Fluorescence Angiography (QFA) is an alternative technique that overcomes this risk. However, it has been shown by the developer that the calculated flow has deviations. After determining the bolus transit time as the most sensitive parameter in flow calculation, we propose a new two-step uncertainty reduction method for flow calculation. The first step is to generate more data in each measurement that results in functions of the parameters. Noise can then be reduced in a second step. Two methods for this step are compared. The first method fits the model for each parameter function separately and calculates flow from models, while the second one fits multiple parameter functions together. The latter method is proven to perform best by in silico tests. Besides, this method reduces the deviation of flow comparing to original QFA as expected. Our approach can be generally used in all QFA applications using two-point theory. Further development is possible if number of dimensions of the achieved parameter data are broadened that results in even more data for processing in the second step.
在脑血运重建术中,血流量值有助于外科医生监测手术质量,例如避免因过度增强灌注而引起脑高灌注综合征。最先进的技术是超声波流量探头,它必须放置在血管周围。这会导致探头与血管接触,在最坏的情况下,会导致破裂。最近发展的术中吲哚菁绿(ICG)定量荧光血管造影(QFA)是克服这种风险的一种替代技术。然而,开发商已经表明,计算的流量有偏差。在确定了流体流动计算中最敏感的参数是流体通过时间后,提出了一种新的两步不确定性降低方法。第一步是在每次测量中生成更多的数据,从而得到参数的函数。然后在第二步中减少噪音。比较了这一步骤的两种方法。第一种方法是对每个参数函数分别拟合模型,从模型中计算流量;第二种方法是对多个参数函数一起拟合。后一种方法经计算机测试证明效果最好。此外,与原QFA相比,该方法还减少了流量的偏差。我们的方法可以在使用两点理论的所有QFA应用中普遍使用。如果所获得的参数数据的维数得到扩大,则可以进一步开发,从而在第二步中处理更多的数据。
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引用次数: 0
Sobel edge detection for quantifying the effectiveness of focused ultrasound thalamotomy for tremor relief 索贝尔边缘检测量化聚焦超声丘脑切开术缓解震颤的有效性
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1005
Vered Aharonson, Michiel Postema, Robyn Gebbie, Jesse Van Der Merwe, Ilana Schlesinger
Abstract Focused ultrasound on the thalamus is employed to relieve tremor in movement disorders. The treatment efficacy is currently assessed by subjective observation of patient tremor during hand movements. The purpose of this study was to create a simple quantitative method to assess tremor based on traditional pen-and-paper spiral drawing that could be employed during treatment and follow-up visits. Image processing was employed to automatically and rapidly clean scanned spiral and line drawings and to isolate the minimal part of the drawing that could provide sufficient data for tremor detection. Sobel edge detection and easily-interpretable statistics of the distribution of edge-angle orientations in the spirals relative to the spiral centres were used as tremor measures. The method was applied to scanned drawings of 122 tremor patients before treatment and in follow-up visits. Discrimination analysis of the tremor measure between drawings in the session before treatment and the follow-up sessions was carried out. The processing yielded correctly cropped and clean spirals. The tremor measure demonstrated consistent tremor reduction in the treated hand drawings in all five follow-up visits during the first year following treatment date in 76 patients from the study cohort. In this study we developed a computational method that rapidly computed tremor severity estimate in an explainable and clinically useful manner from a traditional pen-and-paper spiral drawing. This rapid quantitative and objective tremor assessment can easily be implemented during focused ultrasound treatment and replace the subjective assessment currently employed.
应用聚焦超声在丘脑上治疗运动障碍患者的震颤。治疗效果目前是通过主观观察患者手部运动时的震颤来评估的。本研究的目的是建立一种简单的定量方法来评估震颤基于传统的笔和纸螺旋图,可用于治疗和随访期间。采用图像处理技术自动、快速地清洗扫描的螺旋图和线条图,并分离出图中最小的部分,为震颤检测提供足够的数据。采用索贝尔边缘检测和相对于螺旋中心的螺旋边缘角方向分布的易解释统计量作为震颤测量。将该方法应用于122例震颤患者治疗前及随访时的扫描图。对治疗前和治疗后各阶段图间震颤测量进行了判别分析。加工产生了正确剪裁和干净的螺旋。震颤测量显示,76名研究队列患者在治疗后第一年的所有5次随访中,治疗后的手部震颤持续减少。在这项研究中,我们开发了一种计算方法,以一种可解释的和临床有用的方式,从传统的笔和纸螺旋图快速计算震颤严重程度估计。这种快速、定量和客观的震颤评估可以在聚焦超声治疗中轻松实现,并取代目前采用的主观评估。
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引用次数: 0
A fully automated normothermic machine perfusion system for kidney grafts supporting physiological motivated flow profiles 一种全自动恒温机灌注系统,用于支持生理动力血流剖面的肾移植
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1081
Marc Wiartalla, Frederik Berg, Jahn Kühn, Mateusz Buglowski, Stefan Kowalewski, André Stollenwerk, Christian Bleilevens
Abstract Research showed that the normothermic machine perfusion of kidneys can enable prolonged storage and improve conditions compared to traditional cold storage. For research in this area, there is a demand for a long-term in vitro perfusion setup. In this work, we present a fully automated normothermic machine perfusion (NMP) system as an experimental research platform. The perfusion system is intended as a tool for researching the effects of different perfusion strategies on the kidney. To enable the automation, the NMP system consists of a blood pressure control, a circulation volume level control and a pH-regulation component. The setup is realized as a medical cyber-physical system consisting of networked embedded microcontroller nodes.
研究表明,与传统的冷藏相比,恒温机器灌注肾脏可以延长储存时间并改善条件。对于这一领域的研究,需要一个长期的体外灌注装置。在这项工作中,我们提出了一个全自动恒温机器灌注(NMP)系统作为实验研究平台。灌注系统旨在作为研究不同灌注策略对肾脏影响的工具。为了实现自动化,NMP系统由血压控制、循环量水平控制和ph调节组件组成。该装置实现为一个由网络嵌入式微控制器节点组成的医疗信息物理系统。
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引用次数: 0
Accuracy of CT numbers and electron density calibration for mixtures of materials with low and high-atomic number 低原子序数和高原子序数混合材料CT数和电子密度校准的准确性
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1103
Zehra Ese, Daniel Erni, Waldemar Zylka
Abstract In computed tomography (CT) materials with high-atomic number Z cause image artefacts, thus, errors in CT numbers given in Hounsfield Units (HU). Also, the conventional HU scale (CHU) implemented in CT scanners is truncated, i.e., it does not cover high-Z materials. These restrictions lead to incorrect mapping of CT numbers to electron density, which are used in radiotherapy (RT) treatment planning systems (TPS). Even analytical conversion methods are only permissible for tissue-equivalent materials. In terms of HU-to-density conversion in RT TPS, we investigated the CT numbers of material mixtures up to Z<29 at the CHU and an extended-HU (EHU) scale, respectively, and quantify the systematic errors of image artefacts. In [1] the feasibility of a stoichiometric analytical calibration method were analyzed for metals and adapted for higher accurcy, for energies of 80 kV and 120 kV. In this work, we add results for 100 kV and 140 kV to cover the wide diagnostic range. The CT numbers are effected by physical and machine-based properties and depend strongly on the energy, e.g., for Cu a HU difference of 6 171HU at 80 kV and 140 kV occured. The analytical calibration parameters change with energy by a factor between 2 and 10 depending on the physical process. Although for high- Z materials our calibration procedure remains in conflict with rigorous physics [2], it offers an improved and a practical way to predict electron densities from CT numbers.
在计算机断层扫描(CT)中,具有高原子序数Z的材料会引起图像伪影,因此,在Hounsfield单位(HU)中给出的CT数会出现错误。此外,CT扫描仪中实现的传统HU尺度(CHU)被截断,即它不覆盖高z材料。这些限制导致在放疗(RT)治疗计划系统(TPS)中使用的CT数与电子密度的不正确映射。即使是分析转换方法也只允许用于组织等效材料。在RT TPS中的HU-to-density转换方面,我们分别研究了在CHU和扩展hu (EHU)尺度下高达Z<29的材料混合物的CT数,并量化了图像伪像的系统误差。在[1]中,分析了一种化学计量分析校准方法对金属的可行性,并适应于更高的精度,能量为80千伏和120千伏。在这项工作中,我们增加了100千伏和140千伏的结果,以覆盖较宽的诊断范围。电流互感器数受物理性质和机械性质的影响,并强烈依赖于能量,例如,对于Cu,在80 kV和140 kV时出现了6 171HU的差异。根据物理过程的不同,分析校准参数随能量变化的系数在2到10之间。尽管对于高Z材料,我们的校准程序仍然与严格的物理学相冲突[2],但它提供了一种改进的、实用的方法,可以从CT数预测电子密度。
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引用次数: 0
Core-Shell-Nanoparticles with Superparamagnetic Properties for Novel Applications as Biomaterials 具有超顺磁性的核壳纳米颗粒在生物材料中的新应用
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1167
Valentin Hagemann, Florian Klodwig, Timo Herrmann, Nina Ehlert, Laura Finck, Henning Menzel
Abstract Due to the increasing average age of the population, the number of implants is also increasing and with it the number of explantations. Therefore, facilitated implant removal is of great interest. A nanocomposite consisting of superparamagnetic core-shell nanoparticles (CSNPs) and a synthetic polymer is supposed to be used as implant coating, aiming for a stimulus-inducible modification of the composite’s rheological properties by hyperthermia. Here, the first steps following this concept, the synthesis and modification of the CSNP are reported. In this work magnetite nanoparticles build the core and are surrounded by a periodic mesoporous organisilica (PMO) shell. For this reason, the CSNP are referred to as magnetic PMO (mPMO) particles in the following.
由于人口平均年龄的增长,植入物的数量也在增加,解释的数量也在增加。因此,方便的种植体移除引起了极大的兴趣。一种由超顺磁核壳纳米粒子(csnp)和合成聚合物组成的纳米复合材料被用作植入物涂层,旨在通过热疗刺激诱导改变复合材料的流变特性。本文报道了这一概念的第一步,即CSNP的合成和修饰。在这项工作中,磁铁矿纳米颗粒构建核心,并被周期性介孔有机物(PMO)壳包围。因此,CSNP在下文中被称为磁性PMO (mPMO)颗粒。
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引用次数: 0
Simulation study of the effect of the geometrical parameters on the performance of a beta probe 几何参数对探针性能影响的仿真研究
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1075
Ali Pashazadeh, Christoph Hoeschen
Abstract An intraoperative probe is a small tool used to identify, locate, and dissect pathological lesions during surgery and confirm their removal. The most common type of probe is the gamma probe, which detects gamma-emitting sources. Despite the successful use of gamma probes in clinics, their application can be limited when the background radiation from healthy tissue nearby or the injection site is high. In these cases, the use of beta probes that detect beta-emitting radiotracers would be beneficial. The shorter range of beta radiation compared to gamma radiation would result in improved detection efficacy when background radiation is significant. In this simulation study, we examined how geometrical parameters may impact the performance of a beta probe. Our results showed that the source depth inside the phantom and detector size affected the performance of the beta probe. We also proposed and evaluated two designs of beta probes capable of adjusting their performance.
术中探针是一种小型工具,用于在手术中识别、定位和解剖病理病变并确认其切除。最常见的探针类型是伽马探针,它检测伽马发射源。尽管伽玛探针在诊所成功使用,但当附近健康组织或注射部位的本底辐射很高时,它们的应用可能受到限制。在这些情况下,使用探测发射放射性示踪剂的探针将是有益的。与伽马辐射相比,β辐射的范围更短,当本底辐射显著时,可以提高探测效率。在这个模拟研究中,我们研究了几何参数如何影响β探针的性能。我们的研究结果表明,源深度和探测器的尺寸影响了探针的性能。我们还提出并评估了两种能够调整其性能的β探针设计。
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引用次数: 0
Training and education of young physicians and engineers in the field of endoscopy and laparoscopy – a review of Germany-wide joint cooperation and training possibilities 内窥镜和腹腔镜领域年轻医生和工程师的培训和教育-对全德国联合合作和培训可能性的审查
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1136
Dörte Wichmann, Benedikt Duckwort-Mothes, Bernhard Hirt, Dirk Wilhelm, Jana Steger, Martin Zweimüller, Armin Küllmer, Martin Raithel, Jürgen Maiss, Peter Pott, Thomas Wittenberg
Abstract Introduction: Application-related (hands-on) training and instruction is an essential component in the advanced education of physicians in residency. To teach and train required endoscopic examinations and interventions in a standardized manner, courses are offered by various societies. Within these courses the assistant endoscopists learn and train how to use the technical equipment and how to perform the examinations and related interventions. Similarly, for graduate biomedical engineering students with a job- or research-related interest in the field of endoand laparoscopy, an early involvement and practical introduction to the instrumentation and techniques - if possible already during their studies - can generate a fundamental understanding of the technical requirements as well needs of the physicians. Objective: As various such (hands-on) training-courses for flexible and rigid endoscopy specifically addressing young physicians, surgeons as well as engineers are offered by numerous institutes, this contribution tries do provide a structured overview on/over these possibilities. Material: Known cross-institutional courses in the field of endo- and laparoscopy currently offered in Germany in cooperation of physicians and engineers are listed and briefly described. Results: A total of n = 4 crossinstitutional courses for the introduction and training in flexible and rigid endoscopy have been identified. Discussion: The cross-institutional courses for physicians and technicians in the field of endo- and laparoscopy presented serve to provide a better understanding of the subject matter and the field of either discipline. Questions that arise in the field of endoscopy from physicians can be addressed at an early stage and, if necessary, worked on with little effort. Ideas for new instruments and even new interventions can arise and be pursued through an intensive exchange between technicians and physicians. Collaborations are established on a local basis which will foster national activities in this field and which allow to develop competencies relevant for the industrial sector of medical engineering.
摘要简介:应用相关(动手)培训和指导是住院医师高级教育的重要组成部分。为了以标准化的方式教授和培训所需的内窥镜检查和干预措施,各种协会提供了课程。在这些课程中,内窥镜助理医师学习和培训如何使用技术设备以及如何进行检查和相关干预。同样,对于在内窥镜领域有工作或研究兴趣的生物医学工程研究生来说,早期参与并实际介绍仪器和技术(如果可能的话,已经在学习期间)可以产生对技术要求和医生需求的基本理解。目的:由于许多机构专门为年轻的内科医生、外科医生和工程师提供了各种灵活和严格的内窥镜(实践)培训课程,本文试图对这些可能性提供一个结构化的概述。材料:列出并简要描述了目前在德国由医生和工程师合作提供的内窥镜和腹腔镜领域已知的跨机构课程。结果:共确定了n = 4个跨机构课程,用于介绍和培训柔性和刚性内窥镜。讨论:为内窥镜和腹腔镜领域的医生和技术人员提供的跨机构课程有助于更好地理解这两个学科的主题和领域。在内窥镜检查领域,医生提出的问题可以在早期阶段解决,如果有必要,可以毫不费力地解决。通过技术人员和医生之间的密集交流,可以产生和实现新仪器甚至新干预措施的想法。在地方基础上建立了合作,这将促进这一领域的国家活动,并允许发展与医学工程工业部门相关的能力。
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引用次数: 0
Fabrication of biomimetic antibacterial titanium surfaces by hydrothermal oxidation 水热氧化法制备仿生抗菌钛表面
Q4 Engineering Pub Date : 2023-09-01 DOI: 10.1515/cdbme-2023-1178
Patrick Doll, Lea Kremer, Ralf Ahrens, Litsy Hüschelrath
Abstract Within this paper we demonstrate a novel approach to create antibacterial nanostructures on the implant material titanium grade 23 by a high-pressure oxidation method. Titanium samples were oxidized and resulting nanostructures were characterized using scanning electron microscopy and contact angle measurements. Antibacterial properties were tested using Escherichia coli and Bacillus subtilis as common lab strains. In addition, cytotoxicity was determined according to ISO 10993-5 standards. Results reveal that the fabricated nanostructures have similar antibacterial properties known from different insect wings like dragonflies or cicadas and have no cytotoxic effect.
摘要在本文中,我们展示了一种利用高压氧化法在植入材料钛级23上制备抗菌纳米结构的新方法。利用扫描电镜和接触角测量对钛样品进行氧化和纳米结构表征。以大肠杆菌和枯草芽孢杆菌为常用实验菌株,对其抑菌性能进行了测试。此外,根据ISO 10993-5标准测定细胞毒性。结果表明,制备的纳米结构具有与蜻蜓或蝉等不同昆虫翅膀相似的抗菌性能,且无细胞毒性作用。
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引用次数: 0
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Current Directions in Biomedical Engineering
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