LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 8 of total 8

Search options

  1. Article ; Online: Closing the Gap

    Arne Böcker / Martin Aman / Ulrich Kneser / Leila Harhaus / Frank Siemers / Felix Stang

    Journal of Personalized Medicine, Vol 12, Iss 900, p

    Bridging Peripheral Sensory Nerve Defects with a Chitosan-Based Conduit a Randomized Prospective Clinical Trial

    2022  Volume 900

    Abstract: Introduction: If tensionless nerve coaptation is not possible, bridging the resulting peripheral nerve defect with an autologous nerve graft is still the current gold standard. The concept of conduits as an alternative with different materials and ... ...

    Abstract Introduction: If tensionless nerve coaptation is not possible, bridging the resulting peripheral nerve defect with an autologous nerve graft is still the current gold standard. The concept of conduits as an alternative with different materials and architectures, such as autologous vein conduits or bioartificial nerve conduits, could not replace the nerve graft until today. Chitosan, as a relatively new biomaterial, has recently demonstrated exceptional biocompatibility and material stability with neural lineage cells. The purpose of this prospective randomized clinical experiment was to determine the efficacy of chitosan-based nerve conduits in regenerating sensory nerves in the hand. Materials and methods : Forty-seven patients with peripheral nerve defects up to 26 mm distal to the carpal tunnel were randomized to receive either a chitosan conduit or an autologous nerve graft with the latter serving as the control group. Fifteen patients from the conduit group and seven patients from the control group were available for a 12-month follow-up examination. The primary outcome parameter was tactile gnosis measured with two-point discrimination. The secondary outcome parameters were Semmens Weinstein Monofilament Testing, self-assessed pain, and patient satisfaction. Results: Significant improvement (in static two-point discrimination) was observed six months after trauma (10.7 ± 1.2 mm; p < 0.05) for chitosan-based nerve conduits, but no further improvement was observed after 12 months of regeneration (10.9 ± 1.3 mm). After six months and twelve months, the autologous nerve graft demonstrated comparable results to the nerve conduit, with a static two-point discrimination of 11.0 ± 2.0 mm and 7.9 ± 1.1 mm. Semmes Weinstein Filament Testing in the nerve conduit group showed a continuous improvement over the regeneration period by reaching from 3.1 ± 0.3 after three months up to 3.7 ± 0.4 after twelve months. Autologous nerve grafts presented similar results: 3.3 ± 0.4 after three months and 3.7 ± 0.5 after twelve ...
    Keywords peripheral nerve injuries ; nerve gap ; nerve surgery ; nerve regeneration ; nerve conduit ; chitosan ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  2. Article ; Online: Modern MRI Diagnostics of Upper-Extremity-Related Nerve Injuries—A Prospective Multi-Center Study Protocol for Diagnostics and Follow Up of Peripheral Nerve Injuries

    Martin Aman / Daniel Schwarz / Annette Stolle / Konstantin Davide Bergmeister / Arne H. Boecker / Simeon Daeschler / Martin Bendszus / Ulrich Kneser / Leila Harhaus

    Journal of Personalized Medicine, Vol 12, Iss 1548, p

    2022  Volume 1548

    Abstract: 1) Background: Peripheral nerve injuries are severe injuries with potentially devastating impairment of extremity function. Correct and early diagnosis as well as regular regeneration observation is of utmost importance for individualized reconstruction ...

    Abstract (1) Background: Peripheral nerve injuries are severe injuries with potentially devastating impairment of extremity function. Correct and early diagnosis as well as regular regeneration observation is of utmost importance for individualized reconstruction and the best possible results. Currently, diagnoses and follow-up examinations are based on clinical examinations supported with electroneurography, which often causes delays in treatment and can result in impaired healing. However, there is currently no diagnostic device that can reliably correlate the anatomic–pathological parameters with the functional–pathological changes initially and during therapy. With new technologies such as MR neurography (MRN), precise visualization of potential nerve damage and visualization of the reinnervation processes is assumed to accelerate clinical decision making and accompaniment of individualized treatment. (2) Methods/Design: This prospective clinical study will examine 60 patients after peripheral nerve lesion aged 18–65 years from trauma timepoint onward. Patients should be observed over a period of 18–24 months with regular clinical examinations, electroneurography, and ultrasound to compare the potential of MRN to current gold-standard diagnostic tools. Furthermore, 20 patients with the same inclusion criteria stated above, with an internal fixation and osteosyntheses of humerus fractures, will be examined to determine the visibility of peripheral nerve structures in close proximity to metal. (3) Discussion: Peripheral nerve injuries are often accompanied with severe, expensive, and long-lasting impairment of extremity function. An early and precise diagnosis of the nerve lesion, as well as the healing course, is crucial to indicate the right therapy as soon as possible to save valuable time for nerve regeneration. Here, new technologies such as MRN aim to visualize nerve injuries on fascicular level, providing not only early diagnosis and therapy decisions, but also providing a precise tool for monitoring of ...
    Keywords plastic surgery ; reconstructive surgery ; microsurgery ; nerve damage ; MRI ; neurosonography ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2022-09-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  3. Article ; Online: An Algorithm for Elective Amputation Combined with Targeted Muscle Reinnervation in Complex Regional Pain Syndrome—A Perspective

    Martin Aman / Bahram Biglari / Mirjam Thielen / Arne H. Boecker / Annette Stolle / Daniel Schwarz / Emre Gazyakan / Ulrich Kneser / Leila Harhaus

    Journal of Personalized Medicine, Vol 12, Iss 1169, p

    2022  Volume 1169

    Abstract: Complex regional pain syndrome (CRPS) can result in a devastating condition. For a small number of patients, there is a non-response to any existing multimodal therapies and they ultimately request amputation. Such a drastic and final decision is not ... ...

    Abstract Complex regional pain syndrome (CRPS) can result in a devastating condition. For a small number of patients, there is a non-response to any existing multimodal therapies and they ultimately request amputation. Such a drastic and final decision is not easy to take for both the patient and the surgeon and requires careful and interdisciplinary assessments and considerations. Furthermore, new surgical procedures, such as targeted muscle reinnervation (TMR) and hybrid prosthetic fitting, and multidisciplinary board advice should be included when considering amputation. In order to help other therapeutic teams in decision making for such rare but more than demanding cases, we aimed to propose an advanced algorithm for amputation indications in CRPS patients combining all these new factors. This algorithm consists of extensive pre-operative psychiatric assessment, diagnostic hybrid prosthetic fitting including fMRI analyses, multidisciplinary board advice as well as targeted muscle reinnervation and amputation procedures with final prosthetic fitting and rehabilitation. By involving multiple disciplines, this algorithm should provide optimized and individualized patient treatment on the one hand and a reliable base for decision making for therapists on the other.
    Keywords CRPS ; targeted muscle reinnervation ; TMR ; amputation ; sudeck disease ; nerve transfer ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2022-07-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  4. Article ; Online: Author Correction

    Sarah Hochgeschurz / Konstantin D. Bergmeister / Rickard Brånemark / Martin Aman / Attillio Rocchi / Flavia Restitutti / Michaela Gumpenberger / Matthias E. Sporer / Clemens Gstoettner / Anne-Margarete Kramer / Susanna Lang / Bruno K. Podesser / Oskar C. Aszmann

    Scientific Reports, Vol 11, Iss 1, Pp 1-

    Avian extremity reconstruction via osseointegrated leg-prosthesis for intuitive embodiment

    2021  Volume 1

    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2021-09-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  5. Article ; Online: Avian extremity reconstruction via osseointegrated leg-prosthesis for intuitive embodiment

    Sarah Hochgeschurz / Konstantin D. Bergmeister / Rickard Brånemark / Martin Aman / Attillio Rocchi / Flavia Restitutti / Michaela Gumpenberger / Matthias E. Sporer / Clemens Gstoettner / Anne-Margarete Kramer / Susanna Lang / Bruno K. Podesser / Oskar C. Aszmann

    Scientific Reports, Vol 11, Iss 1, Pp 1-

    2021  Volume 6

    Abstract: Abstract For large avians such as vultures, limb loss leads to loss of ambulation and eventually death from malnutrition. Prosthetic devices may replace the limb, however, conventional prosthetic sockets are not feasible in feathered limbs and the ... ...

    Abstract Abstract For large avians such as vultures, limb loss leads to loss of ambulation and eventually death from malnutrition. Prosthetic devices may replace the limb, however, conventional prosthetic sockets are not feasible in feathered limbs and the extreme stress and strain of unreflected daily use in animals. Osseointegration is a novel technique, where external prosthetic parts are connected directly to a bone anchor to provide a solid skeletal-attachment. This concept provides a high degree of embodiment since osseoperception will provide direct intuitive feedback allowing natural use of the limb in gait and feeding. Here we demonstrate for the first time an osseointegrated bionic reconstruction of a limb in a vulture after a tarsometatarsal amputation with a longterm follow-up.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2021-06-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article ; Online: International Multi-Center Analysis of In-hospital Morbidity and Mortality of Low-Voltage Electrical Injuries

    Alexandra-Maria Warenits / Martin Aman / Clara Zanon / Felix Klimitz / Andreas A. Kammerlander / Anton Laggner / Johannes Horter / Ulrich Kneser / Anna Sophie Bergmeister-Berghoff / Klaus F. Schrögendorfer / Konstantin D. Bergmeister

    Frontiers in Medicine, Vol

    2020  Volume 7

    Abstract: Background : Patients with high- and low-voltage electrical injuries differ in their clinical presentation from minor symptoms to life-threatening conditions. For an adequate diagnosis and treatment strategy a multidisciplinary team is often needed, due ... ...

    Abstract Background : Patients with high- and low-voltage electrical injuries differ in their clinical presentation from minor symptoms to life-threatening conditions. For an adequate diagnosis and treatment strategy a multidisciplinary team is often needed, due to the heterogeneity of the clinical presentation. To minimize costs and medical resources, especially for patients with mild symptoms presenting after low-voltage electrical injuries, risk stratification for the development of further complications is needed.Methods : During 2012–2019 two independent patient cohorts admitted with electrical injuries in two maximum care university hospitals in Germany and Austria were investigated to quantify risk factors for prolonged treatment, the need of surgery and death in low-voltage injuries. High-voltage injuries were used as reference in the analysis of the low-voltage electrical injury.Results : We analyzed 239 admitted patients with low-voltage (75%; 276 ± 118 V), high-voltage (17%; 12.385 ± 28.896 V) or unclear voltage (8%). Overall mortality was 2% (N = 5) associated only with high-voltage injuries. Patients with low-voltage injuries presented with electrocution entry marks (63%), various neurological symptoms (31%), burn injuries (at least second degree) (23%), pain (27%), and cardiac symptoms (9%) including self-limiting thoracic pain and dysrhythmia without any therapeutic need. Seventy three percentage of patients with low-voltage injury were discharged within 24 h. The remaining patients stayed in the hospital (11 ± 10 days) for treatment of entry marks and burns, with an overall need for surgery of 12% in all low-voltage injuries.Conclusions : The only identified risk factors for prolonged hospital stay in patients with low-voltage electrical injuries were the treatment of burns and electric marks. In this multi-center analysis of hospitalized patients, low-voltage electrical injuries were not associated with cardiac arrhythmia or mortality. Therefore, we suggest that asymptomatic patients, without preexisting ...
    Keywords electrical injury ; low-voltage ; high-voltage ; burn trauma ; cardiac arrhythmia ; neurological symptoms ; Medicine (General) ; R5-920
    Subject code 610
    Language English
    Publishing date 2020-11-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  7. Article ; Online: MR Imaging of Peripheral Nerves Using Targeted Application of Contrast Agents

    Vlad Tereshenko / Irena Pashkunova-Martic / Krisztina Manzano-Szalai / Joachim Friske / Konstantin D. Bergmeister / Christopher Festin / Martin Aman / Laura A. Hruby / Johanna Klepetko / Sarah Theiner / Matthias H. M. Klose / Bernhard Keppler / Thomas H. Helbich / Oskar C. Aszmann

    Frontiers in Medicine, Vol

    An Experimental Proof-of-Concept Study

    2020  Volume 7

    Abstract: Introduction: Current imaging modalities for peripheral nerves display the nerve's structure but not its function. Based on a nerve's capacity for axonal transport, it may be visualized by targeted application of a contrast agent and assessing the ... ...

    Abstract Introduction: Current imaging modalities for peripheral nerves display the nerve's structure but not its function. Based on a nerve's capacity for axonal transport, it may be visualized by targeted application of a contrast agent and assessing the distribution through radiological imaging, thus revealing a nerve's continuity. This concept has not been explored, however, may potentially guide the treatment of peripheral nerve injuries. In this experimental proof-of-concept study, we tested imaging through MRI after administering gadolinium-based contrast agents which were then retrogradely transported.Methods: We synthesized MRI contrast agents consisting of paramagnetic agents and various axonal transport facilitators (HSA-DTPA-Gd, chitosan-DTPA-Gd or PLA/HSA-DTPA-Gd). First, we measured their relaxivity values in vitro to assess their radiological suitability. Subsequently, the sciatic nerve of 24 rats was cut and labeled with one of the contrast agents to achieve retrograde distribution along the nerve. One week after surgery, the spinal cords and sciatic nerves were harvested to visualize the distribution of the respective contrast agent using 7T MRI. In vivo MRI measurements were performed using 9.4 T MRI on the 1st, 3rd, and the 7th day after surgery. Following radiological imaging, the concentration of gadolinium in the harvested samples was analyzed using inductively coupled mass spectrometry (ICP-MS).Results: All contrast agents demonstrated high relaxivity values, varying between 12.1 and 116.0 mM−1s−1. HSA-DTPA-Gd and PLA/HSA-DTPA-Gd application resulted in signal enhancement in the vertebral canal and in the sciatic nerve in ex vivo MRI. In vivo measurements revealed significant signal enhancement in the sciatic nerve on the 3rd and 7th day after HSA-DTPA-Gd and chitosan-DTPA-Gd (p < 0.05) application. Chemical evaluation showed high gadolinium concentration in the sciatic nerve for HSA-DTPA-Gd (5.218 ± 0.860 ng/mg) and chitosan-DTPA-Gd (4.291 ± 1.290 ng/mg).Discussion: In this study a novel ...
    Keywords peripheral nerve ; spinal cord ; axonal transport ; contrast agents ; MRI ; nerve injury ; Medicine (General) ; R5-920
    Subject code 610
    Language English
    Publishing date 2020-12-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  8. Article ; Online: Simulating Surgical Skills in Animals

    Konstantin D. Bergmeister / Martin Aman / Anne Kramer / Thilo L. Schenck / Otto Riedl / Simeon C. Daeschler / Oskar C. Aszmann / Helga Bergmeister / Mohammad Golriz / Arianeb Mehrabi / Gabriel Hundeshagen / Perenlei Enkhbaatar / Michael P. Kinsky / Bruno K. Podesser

    Frontiers in Veterinary Science, Vol

    Systematic Review, Costs & Acceptance Analyses

    2020  Volume 7

    Abstract: Background: Modern surgery demands high-quality and reproducibility. Due to new working directives, resident duty hours have been restricted and evidence exists that pure on-the-job training provides insufficient exposure. We hypothesize that ... ...

    Abstract Background: Modern surgery demands high-quality and reproducibility. Due to new working directives, resident duty hours have been restricted and evidence exists that pure on-the-job training provides insufficient exposure. We hypothesize that supplemental simulations in animal models provide a realistic training to augment clinical experiences. This study reviews surgical training models, their costs and survey results illustrating academic acceptance.Methods: Animal models were identified by literature research. Costs were analyzed from multiple German and Austrian training programs. A survey on their acceptance was conducted among faculty and medical students.Results: 915 articles were analyzed, thereof 91 studies described in-vivo animal training models, predominantly for laparoscopy (30%) and microsurgery (24%). Cost-analysis revealed single-training costs between 307€ and 5,861€ depending on model and discipline. Survey results illustrated that 69% of the participants had no experience, but 66% would attend training under experienced supervision. Perceived public acceptance was rated intermediate by medical staff and students (4.26; 1–low, 10 high).Conclusion: Training in animals is well-established and was rated worth attending in a majority of a representative cohort to acquire key surgical skills, in light of reduced clinical exposure. Animal models may therefore supplement the training of tomorrow's surgeons to overcome limited hands-on experience until virtual simulations can provide such educational tools.
    Keywords surgical education ; survey ; cost analysis ; surgical training ; animal model ; Veterinary medicine ; SF600-1100
    Subject code 370 ; 331
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top