Current Directions in Biomedical Engineering最新文献

{"title":"Biomechanical Test Setup for the Investigation of Forehead Suture Techniques","authors":"Carina M. Micheler, Jan J. Lang, Nikolas J. Wilhelm, Victor G. Schaack, Rüdiger von Eisenhart-Rothe, Rainer H. H. Burgkart, Anja Bäumlisberger, Nikolaus Wachtel","doi":"10.1515/cdbme-2023-1133","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1133","url":null,"abstract":"Abstract Wound healing can be delayed if the biomechanical stability of the wound closure is inadequate. Therefore, it is necessary to investigate different suturing techniques for their biomechanical stability. In this study, suturing techniques suitable for the forehead area were investigated. For this application, a special test setup was developed to simulate the curvature of the forehead and the corresponding physiological configuration. The average forehead curvature is 62.24 ± 4.11 mm in radius. To simulate this curvature, the skin specimens are subjected to tensile stress over the spherical surface using a standard uniaxial testing machine. For the evaluation, an automated evaluation tool for MATLAB was also developed. Three different suturing techniques (Straight, Lazy-S, Zigzag) were investigated and tested for their biomechanical stability. Of the three suturing techniques, the Zigzag suture proved to be the most stable with the highest stiffness of 44.23 ± 8.18 % and the highest final failure of 32.60 ± 4.95 % (relative to the control sample without incision). The study has shown that the test setup can be used to investigate different forehead suture techniques.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135394999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Re-evaluation of local anesthesia transtympanic electrical auditory brainstem response in cochlear implant candidacy","authors":"Daniel Polterauer, Giacomo Mandruzzato, Maike Neuling, Marek Polak, Joachim Müller, John Martin Hempel","doi":"10.1515/cdbme-2023-1183","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1183","url":null,"abstract":"Abstract Introduction: The trans-tympanic electrically evoked auditory brainstem response measurement in local anesthesia (= LA-TT-EABR) has been shown as a useful tool in doubtful CI candidacy to objectively evaluate the excitability of the auditory pathway up to the brainstem. Previous studies in this matter were of relatively low subjects number. To update the knowledge of the reliability of LA-TTEABR, we re-evaluated the latest results from a bigger subjects dataset from our clinic and follow up regarding hearing sensation post-operatively. Methods: LA-TT-EABR was performed, as described in previous publications, with a trans-tympanic golf-club electrode in the round window niche for pre-operative stimulation in local anesthesia and with an evoked potential device for EABR recording. Hearing sensations were monitored in the implanted CI subjects. Results: 39 of 40 planned subjects were included in this study. In 22 subjects, a positive LA-TT-EABR was recorded. In 11 subjects, the response was insecure. In 6 subjects, no response was recorded. One subject was excluded because of pain during the paracentesis. Among them, 19 were implanted with a CI, and 18 had hearing sensations with a hearing prosthesis post-operative. The sensitivity and specificity of LA-TTEABR in estimating the excitability of the auditory nerve preoperatively are both 100%. Conclusion: LA-TT-EABR was shown as a reliable pre-operative test to objectively evaluate the auditory brainstem response. In addition to LA-TT-EABR, an analysis of the auditory cortex using LA-TT-EALR may provide correlation and confirmation of LA-TT-EABR results and additional information about cortical reorganization after long deafness.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135735126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prototype of a Coupling Device to Investigate Focused Ultrasound-Induced Inertial Cavitation for Drug Delivery Applications","authors":"Benedikt George, Michel Wittenbrink, Stefan J. Rupitsch, Ula Savšek, Christian Kroh, Dagmar Fischer, Helmut Ermert","doi":"10.1515/cdbme-2023-1041","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1041","url":null,"abstract":"Abstract Focused ultrasound (FUS) can be used as a drug delivery application for localized chemotherapy to treat cancer. The effect of ultrasound-induced inertial cavitation is promising to trigger drug release from nanocarriers. To investigate this effect, usually, a passive cavitation detection setup is employed. However, applying such a setup is challenging for in vivo experiments, as the test object may need to be fixed inside the water tank. Thus, we present a prototype of a coupling device that could significantly simplify experiments. Since this setup favors undesired sound wave interference and their resulting exceedance of the Mechanical Index, we additionally investigated different signal lengths. The occurrence of standing waves at a signal length of 44 cycles can both be derived from a changing cavitation activity and our calculations. The appearing interference also results in a mean increase of the cavitation activity by ≈ 5.1 %, verified by our experiments as well.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135393950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication of flexible intracranial aneurysm models using stereolithography 3D printing","authors":"Janneck Stahl, Leheng Kassem, Philipp Berg, Daniel Behme, Stefan Klebingat, Sylvia Saalfeld","doi":"10.1515/cdbme-2023-1099","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1099","url":null,"abstract":"Abstract The use of 3D printing technology for medical applications is becoming increasingly popular. Recent stereolithography (SLA)-based printing methods allow the generation of complex structures with a high surface quality. This is particularly useful for applications in the neurovascular field, where sophisticated structures are involved. In this study patient-specific intracranial aneurysm models are extracted based on medical image data und printed as thin-walled vascular phantom models. For this purpose, two commercially available 3D printers are used to print flexible vascular models with three different silicone-like elastic resins (Ultracur3D FL 300, Prusament Flex80 and Formlabs Elastic 50A) of various Shore hardness. Three aneurysm models of different size and complexity are chosen. To evaluate the geometric accuracy of the flexible models, angiographic measurements are performed for an exemplary case and morphological parameters are extracted from the generated 3D models. The printed results demonstrate a successful generation of hollow aneurysm phantoms. There are dependencies regarding the print quality from the model to platform positioning for two materials. The quantitative geometric accuracy analysis shows notable differences between the materials. The extracted morphological parameter values for all materials show a mean decrease compared to the original reference model of aneurysm volume (4.5 %) and maximum diameter (1.0 %) as well as an increase of ostium area (6.0 %) and maximum height (4.9 %). However, Formlabs Elastic 50A in particular exhibits just slight reductions with respect to the reference model, with a mean decrease for all parameters of 5.7 % as well as no dependence on printing position and resulting artifacts. The study investigates the feasibility of using SLA-based 3D printing to generate realistic flexible aneurysm phantoms. In this context, the Formlabs Elastic 50A could be identified as potentially applicable for phantom creation in terms of reproducible quality and geometric validity.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135394170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wall-less Flow Phantoms with 3D printed Soluble Filament for Ultrasonic Experiments","authors":"Christian Marinus Huber, Stefan Lyer, Helmut Ermert, Christian Heim, Stefan J. Rupitsch, Ingrid Ullmann","doi":"10.1515/cdbme-2023-1025","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1025","url":null,"abstract":"Abstract Tissue-mimicking materials (TMMs) typically used for ultrasound phantoms include gelatin, agarose and polyvinyl alcohol (PVA). These materials have shown sufficient similarity in ultrasound parameters compared to human tissue. Despite their extensive use for years to generate ultrasound phantoms, no simple and easily reproducible way to generate complex, wall-less ultrasound flow phantoms has been introduced. Commercially available ultrasound flow phantoms are limited to simple flow geometries that do not reflect the complex blood flow in humans. Flow phantoms with complex geometries presented in scientific publications either have walls between TMMs and the flow channel, are limited to one material, or are complicated to produce. In this contribution, we present a method using 3D printing and soluble filament that allows for the reliable and consistent production of complex flow geometries with the typical materials used for ultrasound phantoms and without any walls.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135427372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication of polymer-based stents: Impact of test specimen manufacturing protocol","authors":"Daniela Koper, Sebastian Kaule, Klaus-Peter Schmitz, Niels Grabow, Stefan Oschatz","doi":"10.1515/cdbme-2023-1095","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1095","url":null,"abstract":"Abstract Various manufacturing techniques are available for polymer stent fabrication. Polymer semi-finished products can be prepared using solvent based methods, e.g. dip coating, as well as thermal processes, e.g. extrusion. These different methods may lead to an altered polymer crystal structure, resulting in a different deformation mechanism during mechanical stress. For the material property characterization needed for implant development, the test specimens usually are prepared using laser-cut or die-cut methods. Due to these different preparation protocols, a change in polymer microstructure, causing a material property variation, may also result. For this purpose, comparison of laser-cut versus die-cut of PLLA films has been performed. PLLA films have been prepared by dip-coating and were evaluated with respect to structural, thermal, and mechanical properties. In this study, a combination of uniaxial tensile tests, SEM and DSC studies was used. The results of the mechanical tests showed drastic differences in the elongations at break of die-cut specimens compared to laser-cut ones. The results point out formation of complex crystal structures during the manufacturing process. By the use of SEM imaging and DSC measurements, we were able to attribute these changes to the different plastic deformation mechanisms.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135427374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scalable mesh microelectrode arrays for neural spheroids and organoids","authors":"Peter D. Jones, Tom Stumpp, Michael Mierzejewski, Domenic Pascual, Angelika Stumpf","doi":"10.1515/cdbme-2023-1144","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1144","url":null,"abstract":"Abstract Introduction: Neural organoids promise to help understand the human brain and develop treatments for neurological diseases. Electrophysiological recordings are essential in neural models to evaluate the activity of neural circuits. Mesh microelectrode arrays (MEAs) have been demonstrated to be suitable for organoids and spheroids, and there is demand for easy-to-use devices that can be manufactured at scale. Methods: We present a new mesh MEA device with an easyto- use design. We produce mesh MEA chips on 100 mm carrier wafers and connect individual chips to PCBs by wirebonding. The devices are completed by assembly of a twopiece well and a glass cover slip. Results: Each device contains a suspended hammock-like mesh with 64 microelectrodes. The square grid’s pitch of 200 μm makes the mesh suitable for typical organoid sizes while spreading the electrodes across a 1.4 mm region. The well is designed for fluid handling by pipetting or pump systems. Impedance measurements indicate a high yield of functional microelectrodes, although further effort is needed to produce consistent low impedances. The devices are compatible with commercial amplifiers, while adaptation of the PCB to other formats will be straightforward. Conclusions: Using scalable production methods, we have developed a mesh MEA device design that offers improved ease-of-use. Next steps will include biological validation in collaboration with partners.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"372 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135428646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conception of a Native Connection of Data Gloves with Haptic Feedback to an Augmented Reality-Headset with a planned evaluation in a medical use case","authors":"Christian Gießer, Johannes Schmitt, Vanessa Schmücker, Tanja Joan Eiler, Rainer Brück, Veit Braun","doi":"10.1515/cdbme-2023-1018","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1018","url":null,"abstract":"Abstract The integration of data gloves into Augmented Reality (AR) applications for medical training increases immersion and realism. By using devices with haptic feedback, better and more intuitive control can be achieved. This has implications for learning and exam preparation, but also enables new home-based learning and independence from physical models and presence. Smooth integration and connection of devices is essential for this purpose. This work aims to demonstrate native integration between an augmented reality headset, and a pair of data gloves. In the future, the use of AR and data gloves in medicine will continue to grow and technological advances will create even more realistic and immersive learning opportunities. The study will evaluate if the SkillsLab+ AR application and haptic feedback provide value to medical training and if they can be used effectively in medical education. The implementation shows promise, and the technology may have a future in other areas as well.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135428651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micro-computed tomography shows silent bubbles in squeaky mozzarella","authors":"Craig S. Carlson, Elina Nurkkala, Markus Hannula, Jari Hyttinen, Anu Hopia, Michiel Postema","doi":"10.1515/cdbme-2023-1002","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1002","url":null,"abstract":"Abstract The sound of food is of influence on how its flavour is perceived. Although rarely studied in psychoacoustics, cheese may have a resonating internal structure in the audible spectrum. It has been speculated that this structure or small bubbles that are formed as a result of fermentation are responsible for creating audible acoustic responses. The purpose of this study was to design a mechanical methodology to create audible acoustics from cheese samples and to quantify bubble presence in a sample. One hundred and two samples of mozzarella cheese with 1.5±0.4-cm 3 volumes were subjected to shear from a wetted steel blade, whilst orthogonal force, blade acceleration, and acoustic response were continuously monitored. In addition, micro-computed tomography was performed. It was found that under our measurement conditions, mozzarella was forced to squeak in 10% of the experiments, at fundamental squeak frequencies up to 2 kHz, which indicates that the acoustics come from a resonating porous structure, rather than from resonating bubbles. The micro-computed tomography showed a bubble density of 51 cm −3 . This low bubble density may account for the absence of a high-frequency component in the spectra analysed. Our results confirm the presence of small bubbles in squeaky mozzarella, but these generate frequencies much higher than those recorded.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135428910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A practical example of an integrated interoperable neuromonitoring system based on IEEE 11073 SDC and HL7","authors":"Lea Weßbecher, Kornelius Lente, Thilo B. Krüger, Johann Berger, Juliane Neumann","doi":"10.1515/cdbme-2023-1019","DOIUrl":"https://doi.org/10.1515/cdbme-2023-1019","url":null,"abstract":"Abstract Purpose: With the ongoing work on the Health Level Seven (HL7) standards and the IEEE 11073 Serviceoriented Device Connectivity (SDC) family, the demand for open integration of medical devices in the operating room (OR) has become clear. Nevertheless, there are very few interoperable medical devices available to date. This work describes a practical example of connecting an intraoperative neuromonitoring (IONM) device with a radiofrequency (RF) surgical device based on SDC and with the hospital information system (HIS) based on HL7. Methods: Before starting the surgery, patient-related data must be entered into the neuromonitoring system. To minimize manual input, we integrated an automized patient data query based on HL7, which completes all other necessary data provided by the HIS after entering the patient identification number. During the surgery, while mapping neural structures in the situs using IONM, the parallel operation of RF devices for coagulation generates artifacts in the neuromonitoring signals, which makes a reliable interpretation of the IONM signals impossible. Therefore, we developed an IEEE 11073 SDC interface for the neuromonitoring device and implemented an SDC-based OR control panel. While placing the hand probe for mapping neural structures in the situs, the OR control panel suppresses the coagulation of the electrosurgical instrument and only reenables it, after the mapping has been terminated. After the surgery, the generated IONM report can be uploaded into the HIS using HL7. Therewith it is assigned automatically to the previously selected patient. Result: With the SDC- and HL7-enabled neuromonitoring system, we showed a practical use case of interoperable medical devices to optimize surgical workflow.","PeriodicalId":10739,"journal":{"name":"Current Directions in Biomedical Engineering","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135427376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}