Search results for: nerve message
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 587

Search results for: nerve message

557 Secure Content Centric Network

Authors: Syed Umair Aziz, Muhammad Faheem, Sameer Hussain, Faraz Idris

Abstract:

Content centric network is the network based on the mechanism of sending and receiving the data based on the interest and data request to the specified node (which has cached data). In this network, the security is bind with the content not with the host hence making it host independent and secure. In this network security is applied by taking content’s MAC (message authentication code) and encrypting it with the public key of the receiver. On the receiver end, the message is first verified and after verification message is saved and decrypted using the receiver's private key.

Keywords: content centric network, client-server, host security threats, message authentication code, named data network, network caching, peer-to-peer

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556 RSU Aggregated Message Delivery for VANET

Authors: Auxeeliya Jesudoss, Ashraph Sulaiman, Ratnakar Kotnana

Abstract:

V2V communication brings up several questions of scalability issues although message sharing in vehicular ad-hoc networks comprises of both Vehicle-to-Vehicle communications (V2V) and Vehicle to Infrastructure communication (V2I). It is not an easy task for a vehicle to verify all signatures of the messages sent by its neighboring vehicles in a timely manner, without resulting in message loss. Moreover, the communication overhead of a vehicle to authenticate another vehicle would increase together with the security of the system. Another issue to be addressed is the continuous mobility of vehicles which requires at least some information on the node’s own position to be revealed to the neighboring vehicles. This may facilitate the attacker to congregate information on a node’s position or its mobility patterns. In order to tackle these issues, this paper introduces a RSU aggregated message deliverance scheme called RAMeD. With RAMeD, roadside units (RSUs) are responsible for verifying the identity of the vehicles entering in its range, collect messages from genuine vehicles and to aggregate similar messages into groups before sending them to all the vehicles in its communication range. This aggregation will tremendously improve the rate of message delivery and reduce the message lose ratio by avoiding similar messages being sent to the vehicles redundantly. The proposed protocol is analyzed extensively to evaluate its merits and efficiency for vehicular communication.

Keywords: vehicular ad-hoc networks, V2V, V2I, VANET communication, scalability, message aggregation

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555 Network Conditioning and Transfer Learning for Peripheral Nerve Segmentation in Ultrasound Images

Authors: Harold Mauricio Díaz-Vargas, Cristian Alfonso Jimenez-Castaño, David Augusto Cárdenas-Peña, Guillermo Alberto Ortiz-Gómez, Alvaro Angel Orozco-Gutierrez

Abstract:

Precise identification of the nerves is a crucial task performed by anesthesiologists for an effective Peripheral Nerve Blocking (PNB). Now, anesthesiologists use ultrasound imaging equipment to guide the PNB and detect nervous structures. However, visual identification of the nerves from ultrasound images is difficult, even for trained specialists, due to artifacts and low contrast. The recent advances in deep learning make neural networks a potential tool for accurate nerve segmentation systems, so addressing the above issues from raw data. The most widely spread U-Net network yields pixel-by-pixel segmentation by encoding the input image and decoding the attained feature vector into a semantic image. This work proposes a conditioning approach and encoder pre-training to enhance the nerve segmentation of traditional U-Nets. Conditioning is achieved by the one-hot encoding of the kind of target nerve a the network input, while the pre-training considers five well-known deep networks for image classification. The proposed approach is tested in a collection of 619 US images, where the best C-UNet architecture yields an 81% Dice coefficient, outperforming the 74% of the best traditional U-Net. Results prove that pre-trained models with the conditional approach outperform their equivalent baseline by supporting learning new features and enriching the discriminant capability of the tested networks.

Keywords: nerve segmentation, U-Net, deep learning, ultrasound imaging, peripheral nerve blocking

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554 Model Estimation and Error Level for Okike’s Merged Irregular Transposition Cipher

Authors: Okike Benjamin, Garba E. J. D.

Abstract:

The researcher has developed a new encryption technique known as Merged Irregular Transposition Cipher. In this cipher method of encryption, a message to be encrypted is split into parts and each part encrypted separately. Before the encrypted message is transmitted to the recipient(s), the positions of the split in the encrypted messages could be swapped to ensure more security. This work seeks to develop a model by considering the split number, S and the average number of characters per split, L as the message under consideration is split from 2 through 10. Again, after developing the model, the error level in the model would be determined.

Keywords: merged irregular transposition, error level, model estimation, message splitting

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553 Tick Induced Facial Nerve Paresis: A Narrative Review

Authors: Jemma Porrett

Abstract:

Background: We present a literature review examining the research surrounding tick paralysis resulting in facial nerve palsy. A case of an intra-aural paralysis tick bite resulting in unilateral facial nerve palsy is also discussed. Methods: A novel case of otoacariasis with associated ipsilateral facial nerve involvement is presented. Additionally, we conducted a review of the literature, and we searched the MEDLINE and EMBASE databases for relevant literature published between 1915 and 2020. Utilising the following keywords; 'Ixodes', 'Facial paralysis', 'Tick bite', and 'Australia', 18 articles were deemed relevant to this study. Results: Eighteen articles included in the review comprised a total of 48 patients. Patients' ages ranged from one year to 84 years of age. Ten studies estimated the possible duration between a tick bite and facial nerve palsy, averaging 8.9 days. Forty-one patients presented with a single tick within the external auditory canal, three had a single tick located on the temple or forehead region, three had post-auricular ticks, and one patient had a remarkable 44 ticks removed from the face, scalp, neck, back, and limbs. A complete ipsilateral facial nerve palsy was present in 45 patients, notably, in 16 patients, this occurred following tick removal. House-Brackmann classification was utilised in 7 patients; four patients with grade 4, one patient with grade three, and two patients with grade 2 facial nerve palsy. Thirty-eight patients had complete recovery of facial palsy. Thirteen studies were analysed for time to recovery, with an average time of 19 days. Six patients had partial recovery at the time of follow-up. One article reported improvement in facial nerve palsy at 24 hours, but no further follow-up was reported. One patient was lost to follow up, and one article failed to mention any resolution of facial nerve palsy. One patient died from respiratory arrest following generalized paralysis. Conclusions: Tick paralysis is a severe but preventable disease. Careful examination of the face, scalp, and external auditory canal should be conducted in patients presenting with otalgia and facial nerve palsy, particularly in tropical areas, to exclude the possibility of tick infestation.

Keywords: facial nerve palsy, tick bite, intra-aural, Australia

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552 An Anatomic Approach to the Lingual Artery in the Carotid Triangle in South Indian Population

Authors: Ashwin Rai, Rajalakshmi Rai, Rajanigandha Vadgoankar

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Lingual artery is the chief artery of the tongue and the neighboring structures pertaining to the oral cavity. At the carotid triangle, this artery arises from the external carotid artery opposite to the tip of greater cornua of hyoid bone, undergoes a tortuous course with its first part being crossed by the hypoglossal nerve and runs beneath the digastric muscle. Then it continues to supply the tongue as the deep lingual artery. The aim of this study is to draw surgeon's attention to the course of lingual artery in this area since it can be accidentally lesioned causing an extensive hemorrhage in certain surgical or dental procedures. The study was conducted on 44 formalin fixed head and neck specimens focusing on the anatomic relations of lingual artery. In this study, we found that the lingual artery is located inferior to the digastric muscle and the hypoglossal nerve contradictory to the classical description. This data would be useful during ligation of lingual artery to avoid injury to the hypoglossal nerve in surgeries related to the anterior triangle of neck.

Keywords: anterior triangle, digastric muscle, hypoglossal nerve, lingual artery

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551 Benign Recurrent Unilateral Abducens (6th) Nerve Palsy in 14 Months Old Girl: A Case Report

Authors: Khaled Alabduljabbar

Abstract:

Background: Benign, isolated, recurrent sixth nerve palsy is very rare in children. Here we report a case of recurrent abducens nerve palsy with no obvious etiology. It is a diagnosis of exclusion. A recurrent benign form of 6th nerve palsy, a rarer still palsy, has been described in the literature, and it is of most likely secondary to inflammatory causes, e.g, following viral and bacterial infections. Purpose: To present a case of 14 months old girl with recurrent attacks of isolated left sixth cranial nerve palsy following upper respiratory tract infection. Observation: The patient presented to opthalmology clinic with sudden onset of inward deviation (esotropia) of the left eye with a compensatory left face turn one week following signs of upper respiratory tract infection. Ophthalmological examination revealed large angle esotropia of the left eye in primary position, with complete limitation of abduction of the left eye, no palpebral fissure changes, and abnormal position of the head (left face turn). Visual acuity was normal, and no significant refractive error on cycloplegic refraction for her age. Fundus examination was normal with no evidence of papilledema. There was no relative afferent pupillary defect (RAPD) and no anisocoria. Past medical history and family history were unremarkable, with no history of convulsion attacks or head trauma. Additional workout include CBC. Erythrocyte sedimentation rate, Urgent magnetic resonance imaging (MRI), and angiography of the brain were performed and demonstrated the absence of intracranial and orbital lesions. Referral to pediatric neurologist was also done and concluded no significant finding. The patient showed improvement of the left sixth cranial nerve palsy and left face turn over a period of two months. Seven months since the first attack, she experienced a recurrent attack of left eye esotropia with left face turn concurrent with URTI. The rest of eye examination was again unremarkable. CT scan and MRI scan of brain and orbit were performed and showed only signs of sinusitis with no intracranial pathology. The palsy resolved spontaneously within two months. A third episode of left 6th nerve palsy occurred 6 months later, whichrecovered over one month. Examination and neuroimagingwere unremarkable. A diagnosis of benign recurrent left 6th cranial nerve palsy was made. Conclusion: Benign sixth cranial nerve palsy is always a diagnosis of exclusion given the more serious and life-threatening alternative causes. It seems to have a good prognosis with only supportive measures. The likelihood of benign 6th cranial nerve palsy to resolve completely and spontaneously is high. Observation for at least 6 months without intervention is advisable.

Keywords: 6th nerve pasy, abducens nerve pasy, recurrent nerve palsy, cranial nerve palsy

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550 Botulinum Toxin a in the Treatment of Late Facial Nerve Palsy Complications

Authors: Akulov M. A., Orlova O. R., Zaharov V. O., Tomskij A. A.

Abstract:

Introduction: One of the common postoperative complications of posterior cranial fossa (PCF) and cerebello-pontine angle tumor treatment is a facial nerve palsy, which leads to multiple and resistant to treatment impairments of mimic muscles structure and functions. After 4-6 months after facial nerve palsy with insufficient therapeutic intervention patients develop a postparalythic syndrome, which includes such symptoms as mimic muscle insufficiency, mimic muscle contractures, synkinesis and spontaneous muscular twitching. A novel method of treatment is the use of a recent local neuromuscular blocking agent– botulinum toxin A (BTA). Experience of BTA treatment enables an assumption that it can be successfully used in late facial nerve palsy complications to significantly increase quality of life of patients. Study aim. To evaluate the efficacy of botulinum toxin A (BTA) (Xeomin) treatment in patients with late facial nerve palsy complications. Patients and Methods: 31 patients aged 27-59 years 6 months after facial nerve palsy development were evaluated. All patients received conventional treatment, including massage, movement therapy etc. Facial nerve palsy developed after acoustic nerve tumor resection in 23 (74,2%) patients, petroclival meningioma resection – in 8 (25,8%) patients. The first group included 17 (54,8%) patients, receiving BT-therapy; the second group – 14 (45,2%) patients continuing conventional treatment. BT-injections were performed in synkinesis or contracture points 1-2 U on injured site and 2-4 U on healthy side (for symmetry). Facial nerve function was evaluated on 2 and 4 months of therapy according to House-Brackman scale. Pain syndrome alleviation was assessed on VAS. Results: At baseline all patients in the first and second groups demonstrated аpostparalytic syndrome. We observed a significant improvement in patients receiving BTA after only one month of treatment. Mean VAS score at baseline was 80,4±18,7 and 77,9±18,2 in the first and second group, respectively. In the first group after one month of treatment we observed a significant decrease of pain syndrome – mean VAS score was 44,7±10,2 (р<0,01), whereas in the second group VAS score was as high as 61,8±9,4 points (p>0,05). By the 3d month of treatment pain syndrome intensity continued to decrease in both groups, but, the first group demonstrated significantly better results; mean score was 8,2±3,1 and 31,8±4,6 in the first and second group, respectively (р<0,01). Total House-Brackman score at baseline was 3,67±0,16 in the first group and 3,74±0,19 in the second group. Treatment resulted in a significant symptom improvement in the first group, with no improvement in the second group. After 4 months of treatment House-Brockman score in the first group was 3,1-fold lower, than in the second group (р<0,05). Conclusion: Botulinum toxin injections decrease postparalytic syndrome symptoms in patients with facial nerve palsy.

Keywords: botulinum toxin, facial nerve palsy, postparalytic syndrome, synkinesis

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549 The Effect of Six-Weeks of Elastic Exercises with Reactionary Ropes on Nerve Conduction Velocity and Balance in Females with Multiple Sclerosis

Authors: Mostafa Sarabzadeh, Masoumeh Helalizadeh, Seyyed Mahmoud Hejazi

Abstract:

Multiple Sclerosis is considered as diseases related to central nerve system, the chronic and progressive disease impress on sensory and motor function of people. Due to equilibrium problems in this patients that related to disorder of nerve conduction transmission from central nerve system to organs and the nature of elastic bands that can make changes in neuromuscular junctions and momentary actions, the aim of this research is evaluate elastic training effect by reactionary ropes on nerve conduction velocity (in lower and upper limb) and functional balance in female patients with Multiple Sclerosis. The study was a semi-experimental study that was performed based on pre and post-test method, The statistical community consisted of 16 women with MS in the age mean 25-40yrs, at low and intermediate levels of disease EDSS 1-4 (Expanded Disability Status Scale) that were divided randomly into elastic and control groups, so the training program of experimental group lasted six weeks, 3 sessions per week of elastic exercises with reactionary ropes. Electroneurography parameters (nerve conduction velocity- latency) of Upper and lower nerves (Median, Tibial, Sural, Peroneal) along with balance were investigated respectively by the Electroneurography system (ENG) and Timed up and go (TUG) functional test two times in before and after the training period. After that, To analyze the data were used of Dependent and Independent T-test (with sig level p<0.05). The results showed significant increase in nerve conduction velocity of Sural (p=0.001), Peroneal (p=0.01), Median (p=0.03) except Tibial and also development Latency Time of Tibial (p= 0), Peroneal (p=0), Median (p=0) except Sural. The TUG test showed significant decreases in execution time too (p=0.001). Generally, based on what the obtained data can indicate, modern training with elastic bands can contribute to enhanced nerve conduction velocity and balance in neurosis patients (MS) so lead to reduce problems, promotion of mobility and finally more life expectancy in these patients.

Keywords: balance, elastic bands, multiple sclerosis, nerve conduction, velocity

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548 Peripheral Facial Nerve Palsy after Lip Augmentation

Authors: Sana Ilyas, Kishalaya Mukherjee, Suresh Shetty

Abstract:

Lip Augmentation has become more common in recent years. Patients do not expect to experience facial palsy after having lip augmentation. This poster will present the findings of such a presentation and will discuss the possible pathophysiology and management. (This poster has been published as a paper in the dental update, June 2022) Aim: The aim of the study was to explore the link between facial nerve palsy and lip fillers, to explore the literature surrounding facial nerve palsy, and to discuss the case of a patient who presented with facial nerve palsy with seemingly unknown cause. Methodology: There was a thorough assessment of the current literature surrounding the topic. This included published papers in journals through PubMed database searches and printed books on the topic. A case presentation was discussed in detail of a patient presenting with peripheral facial nerve palsy and associating it with lip augmentation that she had a day prior. Results and Conclusion: Even though the pathophysiology may not be clear for this presentation, it is important to highlight uncommon presentations or complications that may occur after treatment. This can help with understanding and managing similar cases, should they arise.It is also important to differentiate cause and association in order to make an accurate diagnosis. This may be difficult if there is little scientific literature. Therefore, further research can help to improve the understanding of the pathophysiology of similar presentations. This poster has been published as a paper in dental update, June 2022, and therefore shares a similar conclusiom.

Keywords: facial palsy, lip augmentation, causation and correlation, dental cosmetics

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547 Intraoperative Inter Pectoral and Sub Serratus Nerve Blocks Reduce Post Operative Opiate Requirements in Breast Augmentation Surgery

Authors: Conor Mccartney, Mark Lee

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Background: An essential component in ambulatory breast augmentation surgery is good analgesia. The demographic undergoing this operation is usually fit, low risk with few comorbidities. These patients do not require long-term hospitalization and do not want to spend excessive time in the hospital for financial reasons. Opiate analgesia can have significant side effects such as nausea, vomiting and sedation. Reducing volumes of postoperative opiates allows faster ambulation and discharge from day surgery. We have developed two targeted nerve blocks that can be applied by the operating surgeon in a matter of seconds under direct vision, not requiring imaging. Anecdotally we found that these targeted nerve blocks reduced opiate requirements and allowed accelerated discharge and faster return to normal activities. This was then tested in a prospective randomized, double-blind trial. Methods: 20 patients were randomized into saline (n = 10) or Ropivicaine adrenaline solution (n = 10). The operating surgeon and anesthetist were blinded to the solution. All patients were closely followed up and morphine equivalents were accurately recorded. Follow-up pain scores were recorded using the Overall Benefit of Analgesia pain questionnaire. Findings: The Ropivicaine nerve blocks significantly reduced opiate requirements postoperatively (p<0.05). Pain scores were significantly decreased in the study group (p<0.05). There were no side effects attributable to the nerve blocks. Conclusions: Intraoperative targeted nerve blocks significantly reduce postoperative opiate requirements in breast augmentation surgery. This results in faster recovery and higher patient satisfaction.

Keywords: breast augmentation, nerve block, postoperative recovery, opiate analgesia, inter pectoral block, sub serratus block

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546 The Effect of Vitamin "E" on the Peripheral Neurotoxicity of Antimony in Adult Male Albino Rat

Authors: Pymaneh Bairami Rad

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The present work was planned with the aim to study the histological changes that might occur in the sciatic nerve of adult male albino rat following antimony trioxide exposure and to throw more light on the protective role of vitamin "E" on the peripheral neurotoxicity induced by this environmental toxin Sixty adult male albino rats, weighing 183 - 235 grams, were utilized in this work. The animals were divided into 3 groups; each of 20 rats: animals of group I served as control, animals of group II received antimony trioxide daily for 12 successive weeks , animals of group III received antimony trioxide and vitamin "E" daily for the same duration. Antimony trioxide was given in a daily dose of 500 mg/ kg body weight which represents 1/40 of the known LD50 and vitamin "E" was administered in a daily dose of 300 mg/kg body weight. Both antimony trioxide and vitamin "E" were given to the animals by gastric intubation. This research revealed many histological changes in the sciatic nerve, following exposure to antimony trioxide, including Wallerian degeneration in most myelinated nerve fibers with pleomorphic destruction, fragmentation, loss of normal lamination and rupture of myelin sheaths. The axoplasms of these nerve fibers were irregular, degenerated and contained myelin fragments with loss of neurofibrils. Obvious increase in endoneurium was also observed. Concomitant administration of vitamin "E" with antimony trioxide resulted in marked improvement in the histological changes observed in the sciatic nerve.

Keywords: neurotoxicity, antimony, vitamin e, anatomy, histology

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545 How Message Framing and Temporal Distance Affect Word of Mouth

Authors: Camille Lacan, Pierre Desmet

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In the crowdfunding model, a campaign succeeds by collecting the funds required over a predefined duration. The success of a CF campaign depends both on the capacity to attract members of the online communities concerned, and on the community members’ involvement in online word-of-mouth recommendations. To maximize the campaign's success probability, project creators (i.e., an organization appealing for financial resources) send messages to contributors to ask them to issue word of mouth. Internet users relay information about projects through Word of Mouth which is defined as “a critical tool for facilitating information diffusion throughout online communities”. The effectiveness of these messages depends on the message framing and the time at which they are sent to contributors (i.e., at the start of the campaign or close to the deadline). This article addresses the following question: What are the effect of message framing and temporal distance on the willingness to share word of mouth? Drawing on Perspectives Theory and Construal Level Theory, this study examines the interplay between message framing (Gains vs. Losses) and temporal distance (message while the deadline is coming vs. far) on intention to share word of mouth. A between-subject experimental design is conducted to test the research model. Results show significant differences between a loss-framed message (lack of benefits if the campaign fails) associated with a short deadline (ending tomorrow) compared to a gain-framed message (benefits if the campaign succeeds) associated with a distant deadline (ending in three months). However, this effect is moderated by the anticipated regret of a campaign failure and the temporal orientation. These moderating effects contribute to specifying the boundary condition of the framing effect. Handling the message framing and the temporal distance are thus the key decisions to influence the willingness to share word of mouth.

Keywords: construal levels, crowdfunding, message framing, word of mouth

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544 An Assessment of Inferior Dental (IDN) and Lingual Nerve (LN) Injuries Following Third Molar Removal Under LA, IVS, and GA - An Audit and Case-Series

Authors: Aamna Tufail, Catherine Anyanwu

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Introduction/Aims: Neurosensory deficits following third molar removal affect the quality of life markedly. The purpose of this audit was to evaluate the incidence of IDN and LN damage and to compare departmental rates to an established standard. A secondary objective was to provide a descriptive summary of identified cases for clinical learning. Materials and Methods: A retrospective audit was conducted by a telephone survey of 101 patients who had third molar extractions performed under LA, IVS, or GA from January 2019 to June 2020 at a District General Hospital. The results were compared to a clinical standard identified as Cheng et al1. Data collection included mode of surgery, mode of anaesthesia, grade of clinician, assessment of difficulty, severity, and duration of symptoms. Results/Statistics: A total of 101 patients had 136 third molars extracted. Age range was 18-84 years. 44% extractions were under LA, 52% under GA, and 4% under IV sedation. 30% were simple extractions, 68% were surgical removals, 2% were unspecified. 89% extractions were performed by an Associate Specialist, 5% by a consultant, and 6% by unspecified grade of clinician. The rate of IDN injuries was 2.9% (n=4), higher than standard (0.3%). The rate of LN injuries was 0.7% (n=1), same as standard (0.7%). The 5 cases of neurosensory deficits are discussed in detail. Conclusions/Clinical Relevance: The rate of ID nerve injuries was higher than the standard. The rate of LN complications was lower than the standard.

Keywords: inferior dental nerve, lingual nerve, nerve injuries, third molars

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543 The Incidence of Inferior Alveolar Nerve Dysfunction Following Bilateral Sagittal Split Osteotomies: A Single Centre Retrospective Audit in the United Kingdom

Authors: Krupali Mukeshkumar, Jinesh Shah

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Background: Bilateral Sagittal Split Osteotomy (BSSO), used for the correction of mandibular deformities, is a common oral and maxillofacial surgical procedure. Inferior alveolar nerve dysfunction is commonly reported post-operatively by patients as paresthesia or anesthesia. The current literature lacks a consensus on the incidence of inferior alveolar nerve dysfunction as patients are not routinely assessed pre and post-operatively with an objective assessment. The range of incidence varies from 9% to 85% of patients, with some authors arguing that 100% of patients experience nerve dysfunction immediately post-surgery. Systematic reviews have shown a difference between incidence rates at different follow-up periods using objective and subjective methods. Aim: To identify the incidence of inferior alveolar nerve dysfunction following BSSO. Gold standard: Nerve dysfunction incidence rates similar or lower than current literature of 83% day one post-operatively and 18.4% at one year follow up. Setting: A retrospective cross-sectional audit of patients treated between 2017-2019 at the Royal Stoke University Hospital, Maxillofacial and Orthodontic departments. Sample: All patients who underwent a BSSO (with or without le fort one osteotomy) between 2017–2019 were identified from the database. Patients with pre-existing neurosensory disturbance, those who had a genioplasty at the same time and those with no follow-up were excluded. The sample consisted of 121 patients, 37 males and 84 females between the ages of 17-50 years at the time of surgery. Methods: Clinical records of 121 cases were reviewed to assess the age, sex, type of mandibular osteotomy, status of the nerve during the surgical procedure, type of bony split and incidence of nerve dysfunction at follow-up appointments. The surgical procedure was carried out by three Maxillo-facial surgeons and follow-up appointments were carried out in the Orthodontic and Oral and Maxillo-facial departments. Results: 120 patients were treated to correct the mandibular facial deformity and 1 patient was treated for sleep apnoea. Seventeen patients had a mandibular setback and 104 patients had mandibular advancement. 68 patients reported inferior alveolar nerve dysfunction at one week following their surgery. Seventy-six patients had temporary paresthesia present between 2 weeks and 12 months post-surgery. 13 patients had persistent nerve dysfunction at 12 months, of which 1 had a bad bony split during the BSSO. The incidence of nerve dysfunction postoperatively was 6.6% after 1 day, 56.1% at 1 week, 62.8% at 2 weeks, 59.5% between 3-6 weeks, 43.0% between 8-16 weeks and 10.7% at 1 year. Conclusions: The results of this audit show a similar incidence rate to the research gold standard at the one-year follow-up. Future Recommendations: No changes to surgical procedure or technique are indicated, but a need for improved documentation and a standardized approach for assessment of post-operative nerve dysfunction would be beneficial.

Keywords: bilateral sagittal split osteotomy, inferior alveolar nerve, mandible, nerve dysfunction

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542 Bio-Functionalized Silk Nanofibers for Peripheral Nerve Regeneration

Authors: Kayla Belanger, Pascale Vigneron, Guy Schlatter, Bernard Devauchelle, Christophe Egles

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A severe injury to a peripheral nerve leads to its degeneration and the loss of sensory and motor function. To this day, there still lacks a more effective alternative to the autograft which has long been considered the gold standard for nerve repair. In order to overcome the numerous drawbacks of the autograft, tissue engineered biomaterials may be effective alternatives. Silk fibroin is a favorable biomaterial due to its many advantageous properties such as its biocompatibility, its biodegradability, and its robust mechanical properties. In this study, bio-mimicking multi-channeled nerve guidance conduits made of aligned nanofibers achieved by electrospinning were functionalized with signaling biomolecules and were tested in vitro and in vivo for nerve regeneration support. Silk fibroin (SF) extracted directly from silkworm cocoons was put in solution at a concentration of 10wt%. Poly(ethylene oxide) (PEO) was added to the resulting SF solution to increase solution viscosity and the following three electrospinning solutions were made: (1) SF/PEO solution, (2) SF/PEO solution with nerve growth factor and ciliary neurotrophic factor, and (3) SF/PEO solution with nerve growth factor and neurotrophin-3. Each of these solutions was electrospun into a multi-layer architecture to obtain mechanically optimized aligned nanofibrous mats. For in vitro studies, aligned fibers were treated to induce β-sheet formation and thoroughly rinsed to eliminate presence of PEO. Each material was tested using rat embryo neuron cultures to evaluate neurite extension and the interaction with bio-functionalized or non-functionalized aligned fibers. For in vivo studies, the mats were rolled into 5mm long multi-, micro-channeled conduits then treated and thoroughly rinsed. The conduits were each subsequently implanted between a severed rat sciatic nerve. The effectiveness of nerve repair over a period of 8 months was extensively evaluated by cross-referencing electrophysiological, histological, and movement analysis results to comprehensively evaluate the progression of nerve repair. In vitro results show a more favorable interaction between growing neurons and bio-functionalized silk fibers compared to pure silk fibers. Neurites can also be seen having extended unidirectionally along the alignment of the nanofibers which confirms a guidance factor for the electrospun material. The in vivo study has produced positive results for the regeneration of the sciatic nerve over the length of the study, showing contrasts between the bio-functionalized material and the non-functionalized material along with comparisons to the experimental control. Nerve regeneration has been evaluated not only by histological analysis, but also by electrophysiological assessment and motion analysis of two separate natural movements. By studying these three components in parallel, the most comprehensive evaluation of nerve repair for the conduit designs can be made which can, therefore, more accurately depict their overall effectiveness. This work was supported by La Région Picardie and FEDER.

Keywords: electrospinning, nerve guidance conduit, peripheral nerve regeneration, silk fibroin

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541 Bi-Layer Electro-Conductive Nanofibrous Conduits for Peripheral Nerve Regeneration

Authors: Niloofar Nazeri, Mohammad Ali Derakhshan, Reza Faridi Majidi, Hossein Ghanbari

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Injury of peripheral nervous system (PNS) can lead to loss of sensation or movement. To date, one of the challenges for surgeons is repairing large gaps in PNS. To solve this problem, nerve conduits have been developed. Conduits produced by means of electrospinning can mimic extracellular matrix and provide enough surface for further functionalization. In this research, a conductive bilayer nerve conduit with poly caprolactone (PCL), poly (lactic acid co glycolic acid) (PLGA) and MWCNT for promoting peripheral nerve regeneration was fabricated. The conduit was made of longitudinally aligned PLGA nanofibrous sheets in the lumen to promote nerve regeneration and randomly oriented PCL nanofibers on the outer surface for mechanical support. The intra-luminal guidance channel was made out of conductive aligned nanofibrous rolled sheets which are coated with laminin via dopamine. Different properties of electrospun scaffolds were investigated by using contact angle, mechanical strength, degradation time, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The SEM analysis was shown that size range of nanofibrous mat were about 600-750 nm and MWCNTs deposited between nanofibers. The XPS result was shown that laminin attached to the nanofibers surface successfully. The contact-angle and tensile tests analysis revealed that scaffolds have good hydrophilicity and enough mechanical strength. In vitro studies demonstrated that this conductive surface was able to enhance the attachment and proliferation of PC12 and Schwann cells. We concluded that this bilayer composite conduit has good potential for nerve regeneration.

Keywords: conductive, conduit, laminin, MWCNT

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540 Peripheral Neuropathiy After Locoregional Anesthesia

Authors: Dalila Chaid, Yacine Houmel, Mohamed Lamine Belloulou

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Peripheral neuropathy is a rare but worrying complication of peripheral local anaesthesia. It is caused either by needle contact with the nerve root or by the direct toxicity of local anaesthetics, leading to nerve damage, injury or irritation. Although uncommon, it remains a major concern for anaesthetists. The aim of the study was to assess the prevalence of nerve block-associated neuropathy in knee surgery and to identify the contributing factors in order to minimise the occurrence of this complication. The study also assessed the severity and evolution of lesions, as well as the factors leading to neuropathic pain. Methodology: It is a retrospective observational study on cases of neuropathy related to nerve blocks of the lower limb for knee surgery over a period of seven years (2016-2022). The study included a total of 6,000 patients Analyse the anaesthetic and neuropathic pain-related parameters received from these patients to determine the prevalence and severity of neuropathy. Findings: the prevalence of nerve block-related neuropathy in our study is 5.8‰ for the sciatic nerve and 0.9‰ for the femoral nerve. This was higher compared to the reported rates in the literature, which were between 0.0 to 5‰ for the Sciatic nerve and 0.0 to 3.4‰ for the femoral nerve. These findings highlight the importance of identifying and implementing an ideal anesthesia procedure to reduce the risk of neuropathy associated with nerve blocks. Theoretical Importance: The findings of this study contribute to the existing literature on peripheral neuropathy following locoregional anesthesia. By identifying the prevalence and severity of neuropathy related to nerve blocks, as well as the underlying factors, we provide valuable insights for anesthetists to improve patient safety. This study also emphasizes the need for compliance with technical safety rules to minimize the occurrence of neuropathy. Data Collection and Analysis Procedures: For this study, 25 clinics with retrospective data were collected of neuropathy associated with nerve blocks for knee surgery over a span of seven years. Parameters related to anaesthesia and neuropathic pain were analysed to determine prevalence,severity, and progression of neuropathy. Comparison of our results with the existing literature in order to assess their significance. Questions Addressed: This study aims to define the following points: 1. The prevalence of neuropathy associated with nerve blocks for knee surgery. 2. The factors underlying the development of neuropathy after nerve blocks. 3. Reducing the risk of neuropathy by complying with technical safety rules. 4. Assessing the severity and evolution of neuropathic pain in these cases. Conclusion: this study highlights the need for careful consideration and implementation of anesthesia procedures during nerve blocks for knee surgery. The prevalence of neuropathy linked to these blocks was higher compared to the literature, emphasizing the importance of identifying and minimizing contributing factors. Compliance with technical safety rules is crucial to reduce the risk of peripheral neuropathy. This study provides valuable insights to anesthetists and contributes to improving patient safety in the field of locoregional anesthesia.

Keywords: phantom limb, neuropathic pain, lower limb amputee, ultrasound-guided locoreginal anesthesia

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539 The Effect of Ice in Pain Control before Digital Nerve Block

Authors: Fatemeh Rasooli, Behzad Simiari, Pooya Payandemehr, Amir Nejati, Maryam Bahreini, Atefeh Abdollahi

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Introduction: Pain is a complex physiological reaction to tissue injury. In the course of painful procedures such as nerve block, ice has been shown to be a feasible and inexpensive material to control pain. It delays nerve conduction, actives other senses and reduces inflammatory and painful responses. This study assessed the effect of ice in reducing pain caused by needling and infiltration during digital block. Patient satisfaction recorded as a secondary outcome. Methods: This study was designed as a non-blinded randomized clinical trial approved by Tehran University of Medical Sciences Ethical Committee. Informed consent was taken from all the participants who were then randomly divided into two groups. Digital block performed by standard approach in selected patients. Tubes of ice were prepared in gloves and were fragmented at a time of application for circling around the finger. Tubes were applied for 6 minutes before digital nerve block in the site of needling in the case group. Patients in the control group underwent digital nerve block with the conventional method without ice administration. Numeric Rating Scale (NRS) used for grading pain. 0 used for no pain and 10 for the worst pain that patient had experienced until now. Scores were analyzed by Wilcoxon Rank Sum test and compared in case and control groups. Results: 100 patients aged 16-50 years were enrolled. Mean NRS scores with and without ice were 1.5 mm (S.D ± 1.44) and 6.8 mm (S.D ± 1.40) for needling pain and for infiltration pain were 2.7mm ( S.D ±1.65) and 8.5mm ( S.D ± 1.47), respectively (p<0.001). Besides, patients’ satisfactions were significantly higher in the ice group (p<0.001). Conclusion: Application of ice for 6 minutes significantly reduced pain of needling and infiltration in digital nerve block; thus, it seems to be a feasible and inexpensive material which acts effectively to decrease pain and stress before the procedure.

Keywords: digital block, ice, needle, pain

Procedia PDF Downloads 223
538 Electromagnetic-Mechanical Stimulation on PC12 for Enhancement of Nerve Axonal Extension

Authors: E. Nakamachi, K. Matsumoto, K. Yamamoto, Y. Morita, H. Sakamoto

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In recently, electromagnetic and mechanical stimulations have been recognized as the effective extracellular environment stimulation technique to enhance the defected peripheral nerve tissue regeneration. In this study, we developed a new hybrid bioreactor by adopting 50 Hz uniform alternative current (AC) magnetic stimulation and 4% strain mechanical stimulation. The guide tube for nerve regeneration is mesh structured tube made of biodegradable polymer, such as polylatic acid (PLA). However, when neural damage is large, there is a possibility that peripheral nerve undergoes necrosis. So it is quite important to accelerate the nerve tissue regeneration by achieving enhancement of nerve axonal extension rate. Therefore, we try to design and fabricate the system that can simultaneously load the uniform AC magnetic field stimulation and the stretch stimulation to cells for enhancement of nerve axonal extension. Next, we evaluated systems performance and the effectiveness of each stimulation for rat adrenal pheochromocytoma cells (PC12). First, we designed and fabricated the uniform AC magnetic field system and the stretch stimulation system. For the AC magnetic stimulation system, we focused on the use of pole piece structure to carry out in-situ microscopic observation. We designed an optimum pole piece structure using the magnetic field finite element analyses and the response surface methodology. We fabricated the uniform AC magnetic field stimulation system as a bio-reactor by adopting analytically determined design specifications. We measured magnetic flux density that is generated by the uniform AC magnetic field stimulation system. We confirmed that measurement values show good agreement with analytical results, where the uniform magnetic field was observed. Second, we fabricated the cyclic stretch stimulation device under the conditions of particular strains, where the chamber was made of polyoxymethylene (POM). We measured strains in the PC12 cell culture region to confirm the uniform strain. We found slightly different values from the target strain. Finally, we concluded that these differences were allowable in this mechanical stimulation system. We evaluated the effectiveness of each stimulation to enhance the nerve axonal extension using PC12. We confirmed that the average axonal extension length of PC12 under the uniform AC magnetic stimulation was increased by 16 % at 96 h in our bio-reactor. We could not confirm that the axonal extension enhancement under the stretch stimulation condition, where we found the exfoliating of cells. Further, the hybrid stimulation enhanced the axonal extension. Because the magnetic stimulation inhibits the exfoliating of cells. Finally, we concluded that the enhancement of PC12 axonal extension is due to the magnetic stimulation rather than the mechanical stimulation. Finally, we confirmed that the effectiveness of the uniform AC magnetic field stimulation for the nerve axonal extension using PC12 cells.

Keywords: nerve cell PC12, axonal extension, nerve regeneration, electromagnetic-mechanical stimulation, bioreactor

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537 Propagation of the Effects of Certain Types of Military Psychological Operations in a Networked Population

Authors: Colette Faucher

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In modern asymmetric conflicts, the Armed Forces generally have to intervene in countries where the internal peace is in danger. They must make the local population an ally in order to be able to deploy the necessary military actions with its support. For this purpose, psychological operations (PSYOPs) are used to shape people’s behaviors and emotions by the modification of their attitudes in acting on their perceptions. PSYOPs aim at elaborating and spreading a message that must be read, listened to and/or looked at, then understood by the info-targets in order to get from them the desired behavior. A message can generate in the info-targets, reasoned thoughts, spontaneous emotions or reflex behaviors, this effect partly depending on the means of conveyance used to spread this message. In this paper, we focus on psychological operations that generate emotions. We present a method based on the Intergroup Emotion Theory, that determines, from the characteristics of the conveyed message and of the people from the population directly reached by the means of conveyance (direct info-targets), the emotion likely to be triggered in them and we simulate the propagation of the effects of such a message on indirect info-targets that are connected to them through the social networks that structure the population.

Keywords: military psychological operations, social identity, social network, emotion propagation

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536 Designing Stochastic Non-Invasively Applied DC Pulses to Suppress Tremors in Multiple Sclerosis by Computational Modeling

Authors: Aamna Lawrence, Ashutosh Mishra

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Tremors occur in 60% of the patients who have Multiple Sclerosis (MS), the most common demyelinating disease that affects the central and peripheral nervous system, and are the primary cause of disability in young adults. While pharmacological agents provide minimal benefits, surgical interventions like Deep Brain Stimulation and Thalamotomy are riddled with dangerous complications which make non-invasive electrical stimulation an appealing treatment of choice for dealing with tremors. Hence, we hypothesized that if the non-invasive electrical stimulation parameters (mainly frequency) can be computed by mathematically modeling the nerve fibre to take into consideration the minutest details of the axon morphologies, tremors due to demyelination can be optimally alleviated. In this computational study, we have modeled the random demyelination pattern in a nerve fibre that typically manifests in MS using the High-Density Hodgkin-Huxley model with suitable modifications to account for the myelin. The internode of the nerve fibre in our model could have up to ten demyelinated regions each having random length and myelin thickness. The arrival time of action potentials traveling the demyelinated and the normally myelinated nerve fibre between two fixed points in space was noted, and its relationship with the nerve fibre radius ranging from 5µm to 12µm was analyzed. It was interesting to note that there were no overlaps between the arrival time for action potentials traversing the demyelinated and normally myelinated nerve fibres even when a single internode of the nerve fibre was demyelinated. The study gave us an opportunity to design DC pulses whose frequency of application would be a function of the random demyelination pattern to block only the delayed tremor-causing action potentials. The DC pulses could be delivered to the peripheral nervous system non-invasively by an electrode bracelet that would suppress any shakiness beyond it thus paving the way for wearable neuro-rehabilitative technologies.

Keywords: demyelination, Hodgkin-Huxley model, non-invasive electrical stimulation, tremor

Procedia PDF Downloads 115
535 Prosody of Text Communication: Inducing Synchronization and Coherence in Chat Conversations

Authors: Karolina Ziembowicz, Andrzej Nowak

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In the current study, we examined the consequences of adding prosodic cues to text communication by allowing users to observe the process of message creation while engaged in dyadic conversations. In the first condition, users interacted through a traditional chat that requires pressing ‘enter’ to make a message visible to an interlocutor. In another, text appeared on the screen simultaneously as the sender was writing it, letter after letter (Synchat condition), so that users could observe the varying rhythm of message production, precise timing of message appearance, typos and their corrections. The results show that the ability to observe the dynamics of message production had a twofold effect on the social interaction process. First, it enhanced the relational aspect of communication – interlocutors synchronized their emotional states during the interaction, their communication included more statements on relationship building, and they evaluated the Synchat medium as more personal and emotionally engaging. Second, it increased the coherence of communication, reflected in greater continuity of the topics raised in Synchat conversations. The results are discussed from the interaction design (IxD) perspective.

Keywords: chat communication, online conversation, prosody, social synchronization, interaction incoherence, relationship building

Procedia PDF Downloads 133
534 Islam, Tolerance and Anti-Terrorism: A Critical Assessment with Reference to the Royal 'Amman Message'

Authors: Adnan M. Al Assaf

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This research project aims to assess the methods of enhancing tolerant thinking and behavior among Muslim societies. This is in addition to spreading the anti-terrorist approach in their communities. The critical assessment for the Islamic major texts in question is the selected way for convincing, as Muslims adopt these sources as the authentic references for their lives and cultures. Moreover, this research devotes a special room to the analysis of the royal ‘Amman Message’ as a contemporary Islamic approach for enhancing tolerance and anti-terrorism from an Islamic perspective. The paper includes the study of the related concepts, texts, practical applications, with some reference to the history of Islam in human interaction, accepting the others, mercy with minorities, protecting human rights. Furthermore, it assesses the methods of enhancing tolerance and minimizing the terrorist thinking and behavior practically, in the view of Amman message, as well.

Keywords: Islam, tolerance, anti-terrorism, coexistence, Amman Message

Procedia PDF Downloads 447
533 Secure Message Transmission Using Meaningful Shares

Authors: Ajish Sreedharan

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Visual cryptography encodes a secret image into shares of random binary patterns. If the shares are exerted onto transparencies, the secret image can be visually decoded by superimposing a qualified subset of transparencies, but no secret information can be obtained from the superposition of a forbidden subset. The binary patterns of the shares, however, have no visual meaning and hinder the objectives of visual cryptography. In the Secret Message Transmission through Meaningful Shares a secret message to be transmitted is converted to grey scale image. Then (2,2) visual cryptographic shares are generated from this converted gray scale image. The shares are encrypted using A Chaos-Based Image Encryption Algorithm Using Wavelet Transform. Two separate color images which are of the same size of the shares, taken as cover image of the respective shares to hide the shares into them. The encrypted shares which are covered by meaningful images so that a potential eavesdropper wont know there is a message to be read. The meaningful shares are transmitted through two different transmission medium. During decoding shares are fetched from received meaningful images and decrypted using A Chaos-Based Image Encryption Algorithm Using Wavelet Transform. The shares are combined to regenerate the grey scale image from where the secret message is obtained.

Keywords: visual cryptography, wavelet transform, meaningful shares, grey scale image

Procedia PDF Downloads 440
532 Comparative Study of Analgesic Efficacy of Ultrasound Guided Femoral Nerve Block Versus Intravenous Fentanyl Injection in Fracture Femur Patients at Emergency Department

Authors: Asmaa Hamdy, Israa Nassar, Tarek Aly

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Introduction: Femoral fractures are the most common presentation in the Emergency Department (ED), and they can present as isolated injuries or as part of a polytrauma situation. To provide optimum pain management care to these patients, practitioners must be well prepared and current with utilizing modern evidence-based knowledge and practices. Management of pain associated with fracture femur in the emergency department has a critical role in the satisfaction of patients and preventing further complications. This study aimed to evaluate the analgesic efficacy of ultrasound-guided femoral nerve block compared with intravenous fentanyl in fractures of the femur in patients presented to the Emergency Department. Patients and Methods: Fifty patients with femur fractures were divided into two groups: Group A: In this group (twenty-five patients) were given intravenous fentanyl 2 micro-grams/kg and re-assessed for pain by Visual Analogue Score (VAS). Group B: In this group (twenty-five patients) underwent ultrasonography-guided femoral nerve block and were re-assessed for pain by VAS. Results: VAS score on the movement of the fractured limb between group A and group B at a 10-minute post-intervention period shows P= 0.043, and hence the difference is significant. VAS score on the movement of the fractured limb between group A and group B during a 10-minute post-intervention period showed a significant difference. Seventeen patients in group A had major PID with a percentage of 63% VS 10 patients in group B with a percentage of 37%. conclusion: both femoral nerve block and intravenous fentanyl are effective in relieving pain in patients with femur fractures. But femoral nerve block provides better and more intense analgesia and major pain intensity difference in less time. Moreover, the use of FNB had fewer side effects and more Hemodynamics stability compared to opioids.

Keywords: femur fracture, nerve block, fentanyl, ultrasound guided

Procedia PDF Downloads 87
531 Development of Three-Dimensional Bio-Reactor Using Magnetic Field Stimulation to Enhance PC12 Cell Axonal Extension

Authors: Eiji Nakamachi, Ryota Sakiyama, Koji Yamamoto, Yusuke Morita, Hidetoshi Sakamoto

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The regeneration of injured central nerve network caused by the cerebrovascular accidents is difficult, because of poor regeneration capability of central nerve system composed of the brain and the spinal cord. Recently, new regeneration methods such as transplant of nerve cells and supply of nerve nutritional factor were proposed and examined. However, there still remain many problems with the canceration of engrafted cells and so on and it is strongly required to establish an efficacious treating method of a central nerve system. Blackman proposed the electromagnetic stimulation method to enhance the axonal nerve extension. In this study, we try to design and fabricate a new three-dimensional (3D) bio-reactor, which can load a uniform AC magnetic field stimulation on PC12 cells in the extracellular environment for enhancement of an axonal nerve extension and 3D nerve network generation. Simultaneously, we measure the morphology of PC12 cell bodies, axons, and dendrites by the multiphoton excitation fluorescence microscope (MPM) and evaluate the effectiveness of the uniform AC magnetic stimulation to enhance the axonal nerve extension. Firstly, we designed and fabricated the uniform AC magnetic field stimulation bio-reactor. For the AC magnetic stimulation system, we used the laminated silicon steel sheets for a yoke structure of 3D chamber, which had a high magnetic permeability. Next, we adopted the pole piece structure and installed similar specification coils on both sides of the yoke. We searched an optimum pole piece structure using the magnetic field finite element (FE) analyses and the response surface methodology. We confirmed that the optimum 3D chamber structure showed a uniform magnetic flux density in the PC12 cell culture area by using FE analysis. Then, we fabricated the uniform AC magnetic field stimulation bio-reactor by adopting analytically determined specifications, such as the size of chamber and electromagnetic conditions. We confirmed that measurement results of magnetic field in the chamber showed a good agreement with FE results. Secondly, we fabricated a dish, which set inside the uniform AC magnetic field stimulation of bio-reactor. PC12 cells were disseminated with collagen gel and could be 3D cultured in the dish. The collagen gel were poured in the dish. The collagen gel, which had a disk shape of 6 mm diameter and 3mm height, was set on the membrane filter, which was located at 4 mm height from the bottom of dish. The disk was full filled with the culture medium inside the dish. Finally, we evaluated the effectiveness of the uniform AC magnetic field stimulation to enhance the nurve axonal extension. We confirmed that a 6.8 increase in the average axonal extension length of PC12 under the uniform AC magnetic field stimulation at 7 days culture in our bio-reactor, and a 24.7 increase in the maximum axonal extension length. Further, we confirmed that a 60 increase in the number of dendrites of PC12 under the uniform AC magnetic field stimulation. Finally, we confirm the availability of our uniform AC magnetic stimulation bio-reactor for the nerve axonal extension and the nerve network generation.

Keywords: nerve regeneration, axonal extension , PC12 cell, magnetic field, three-dimensional bio-reactor

Procedia PDF Downloads 160
530 The Rupture Potential of Nerve Tissue Constrained Intracranial Saccular Aneurysm

Authors: M. Alam, P. Seshaiyer

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The rupture predictability of intracranial aneurysm is one of the most important parameters for physicians in surgical treatment. As most of the intracranial aneurysms are asymptomatic, still the rupture potential of both symptomatic and asymptomatic lesions is relatively unknown. Moreover, an intracranial aneurysm constrained by a nerve tissue might be a common scenario for a physician to deal with during the treatment process. Here, we perform a computational modeling of nerve tissue constrained intracranial saccular aneurysm to show a protective role of constrained tissue on the aneurysm. A comparative parametric study of the model also performs taking long constraint, medium constraint, short constraint, point contact, narrow neck aneurysm, wide neck aneurysm as parameters for the analysis. Results show that contact constraint aneurysm generates less stress near the fundus compared to no constraint aneurysm, hence works as a protective wall for the aneurysm not to be ruptured.

Keywords: rupture potential, intracranial saccular aneurysm, anisotropic hyper-elastic material, finite element analysis

Procedia PDF Downloads 201
529 Biocompatibility Tests for Chronic Application of Sieve-Type Neural Electrodes in Rats

Authors: Jeong-Hyun Hong, Wonsuk Choi, Hyungdal Park, Jinseok Kim, Junesun Kim

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Identifying the chronic functions of an implanted neural electrode is an important factor in acquiring neural signals through the electrode or restoring the nerve functions after peripheral nerve injury. The purpose of this study was to investigate the biocompatibility of the chronic implanted neural electrode into the sciatic nerve. To do this, a sieve-type neural electrode was implanted at proximal and distal ends of a transected sciatic nerve as an experimental group (Sieve group, n=6), and the end-to-end epineural repair was operated with the cut sciatic nerve as a control group (reconstruction group, n=6). All surgeries were performed on the sciatic nerve of the right leg in Sprague Dawley rats. Behavioral tests were performed before and 1, 4, 7, 10, 14, and weekly days until 5 months following surgery. Changes in sensory function were assessed by measuring paw withdrawal responses to mechanical and cold stimuli. Motor function was assessed by motion analysis using a Qualisys program, which showed a range of motion (ROM) related to the joints. Neurofilament-heavy chain and fibronectin expression were detected 5 months after surgery. In both groups, the paw withdrawal response to mechanical stimuli was slightly decreased from 3 weeks after surgery and then significantly decreased at 6 weeks after surgery. The paw withdrawal response to cold stimuli was increased from 4 days following surgery in both groups and began to decrease from 6 weeks after surgery. The ROM of the ankle joint was showed a similar pattern in both groups. There was significantly increased from 1 day after surgery and then decreased from 4 days after surgery. Neurofilament-heavy chain expression was observed throughout the entire sciatic nerve tissues in both groups. Especially, the sieve group was showed several neurofilaments that passed through the channels of the sieve-type neural electrode. In the reconstruction group, however, a suture line was seen through neurofilament-heavy chain expression up to 5 months following surgery. In the reconstruction group, fibronectin was detected throughout the sciatic nerve. However, in the sieve group, the fibronectin was observed only in the surrounding nervous tissues of an implanted neural electrode. The present results demonstrated that the implanted sieve-type neural electrode induced a focal inflammatory response. However, the chronic implanted sieve-type neural electrodes did not cause any further inflammatory response following peripheral nerve injury, suggesting the possibility of the chronic application of the sieve-type neural electrodes. This work was supported by the Basic Science Research Program funded by the Ministry of Science (2016R1D1A1B03933986), and by the convergence technology development program for bionic arm (2017M3C1B2085303).

Keywords: biocompatibility, motor functions, neural electrodes, peripheral nerve injury, sensory functions

Procedia PDF Downloads 135
528 A Rare Case of Popliteal Artery Aneurysm Presenting with Foot Drop

Authors: John Yahng, Riteesh Bookun

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Popliteal artery aneurysms (PAAs) are the most common arterial aneurysm of the periphery. It is defined as focal dilation of the artery more than 50% of the normal vessel diameter which usually varies between 7 mm to 11 mm. The most common presentation for PAAs is claudication due to luminal stenmosis secondary to mural thrombus or acute limb ischaemia due to occlusive thrombosis or distal thromboembolism. It is less common for patients to present with non-ischaemic symptoms secondary to mass effect and compression of adjacent structures, and of these, presentation with common peroneal nerve compression is particularly uncommon. We present a rare case of a 92-year-old female patient presenting with 4-month history of left foot drop with radiological evidence of common peroneal nerve compression secondary to PAA of 22 mm by21mm in size. To the best of our knowledge, this is the smallest reported popliteal aneurysm presenting with foot drop. We also present the endovascular treatment option taken in our case.

Keywords: aneurysm, foot drop, peroneal nerve, popliteal

Procedia PDF Downloads 286