86 results match your criteria selective fascicular

Selective Neuromodulation of the Vagus Nerve.

Front Neurosci 2021 24;15:685872. Epub 2021 May 24.

Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.

Vagus nerve stimulation (VNS) is an effective technique for the treatment of refractory epilepsy and shows potential for the treatment of a range of other serious conditions. However, until now stimulation has generally been supramaximal and non-selective, resulting in a range of side effects. Selective VNS (sVNS) aims to mitigate this by targeting specific fiber types within the nerve to produce functionally specific effects. Read More

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His-Purkinje system longitudinal dissociation: From bench to bedside. A case of output-dependent fascicular capture.

J Cardiovasc Electrophysiol 2021 04 8;32(4):1174-1177. Epub 2021 Mar 8.

Department of Cardiology, Immacolata Concezione Hospital, Piove di Sacco, Padua, Italy.

Introduction: Histological studies reported that the His bundle (HB) is partitioned into narrow cords by collagen running in its long axis, providing the anatomical setting necessary for its longitudinal dissociation. Further confirmations came from the demonstration that direct HB pacing normalizes the QRS axis and duration in subjects with proximal HB lesions causing bundle branch block. However, there is no evidence of the possibility of selective HB partitions pacing destined to the composition of branches and fascicles. Read More

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Imaging fascicular organization of rat sciatic nerves with fast neural electrical impedance tomography.

Nat Commun 2020 12 7;11(1):6241. Epub 2020 Dec 7.

Department of Medical Physics and Biomedical Engineering, University College London, London, UK.

Imaging compound action potentials (CAPs) in peripheral nerves could help avoid side effects in neuromodulation by selective stimulation of identified fascicles. Existing methods have low resolution, limited imaging depth, or are invasive. Fast neural electrical impedance tomography (EIT) allows fascicular CAP imaging with a resolution of <200 µm, <1 ms using a non-penetrating flexible nerve cuff electrode array. Read More

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December 2020

Quantified Morphology of the Cervical and Subdiaphragmatic Vagus Nerves of Human, Pig, and Rat.

Front Neurosci 2020 4;14:601479. Epub 2020 Nov 4.

Department of Biomedical Engineering, Duke University, Durham, NC, United States.

It is necessary to understand the morphology of the vagus nerve (VN) to design and deliver effective and selective vagus nerve stimulation (VNS) because nerve morphology influences fiber responses to electrical stimulation. Specifically, nerve diameter (and thus, electrode-fiber distance), fascicle diameter, fascicular organization, and perineurium thickness all significantly affect the responses of nerve fibers to electrical signals delivered through a cuff electrode. We quantified the morphology of cervical and subdiaphragmatic VNs in humans, pigs, and rats: effective nerve diameter, number of fascicles, effective fascicle diameters, proportions of endoneurial, perineurial, and epineurial tissues, and perineurium thickness. Read More

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November 2020

Simulation-Based Optimization of Figure-of-Eight Coil Designs and Orientations for Magnetic Stimulation of Peripheral Nerve.

IEEE Trans Neural Syst Rehabil Eng 2020 12 28;28(12):2901-2913. Epub 2021 Jan 28.

Although magnetic neural stimulation has many advantages over electrical neural stimulation, its main disadvantages are higher energy requirement and poor stimulation selectivity. The orientation and location of the coil with respect to the stimulation site play a critical role in determining the stimulation threshold and stimulation selectivity. Utilizing numerical simulations in this work, we optimized the design parameters, orientation, and positioning of magnetic coils with respect to the peripheral nerve for improved stimulation efficacy. Read More

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December 2020

Evaluating Microelectrode Arrays in Peripheral Nerve Using Micro Computed Tomography

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:3432-3435

Many advances have been made with imaging of implanted neural devices; however, the ability to image whole nerve samples remains limited. Further, few imaging modalities are well suited for visualizing both whole devices in vivo and individual microelectrodes within a nerve. In this study, we used micro-computed tomography (micro-CT) to evaluate Wireless Floating Microelectrode Arrays (WMFAs) implanted in rat sciatic nerve at the level of whole devices and individual electrodes. Read More

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Selective Wireless Stimulation of Rat Sciatic Nerve

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:3407-3410

Chronic stability of functional performance is a significant challenge to the success of implantable devices for neural stimulation and recording. Integrating wireless technology with typical microelectrode array designs is one approach that may reduce instances of mechanical failure and improve the long-term performance of neural devices. We have investigated the long-term stability of Wireless Floating Microelectrode Arrays (WMFAs) implanted in rat sciatic nerve, and their ability to selectively recruit muscles in the hind limb via neural stimulation. Read More

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Selective atrophy of the brachialis muscle in neuralgic amyotrophy: ultrasound imaging of fascicular nerve damage.

J Neurol Neurosurg Psychiatry 2020 10 30;91(10):1118-1119. Epub 2020 Jul 30.

Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy

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October 2020

H subtype vascular endothelial cells in human femoral head: an experimental verification.

Ann Palliat Med 2020 Jul 22;9(4):1497-1505. Epub 2020 Jun 22.

Department of Orthopedics, China-Japan Friendship Hospital, National Health and Family Planning Commission of the People's Republic of China, Beijing, China.

Background: Osteonecrosis of the femoral head (ONFH) is difficult to treat, and leads to an impaired microcirculation of the femoral head and activation of a repair response. The type H vessels have been proved to mediate the growth of the bone vasculature and couple angiogenesis to osteogenesis. The aim of the study is to investigate the experimental verification of H subtype vascular endothelial cells (HSVECs) in the human femoral head. Read More

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Selective Fascicular Involvement of the Median Nerve Trunk Causing Pseudo-Anterior Interosseous Nerve Syndrome: Ultrasound and MR Imaging Features.

Yonsei Med J 2020 Jun;61(6):547-552

Department of Radiology, Nowon Eulji Medical Center, Eulji University, Seoul, Korea.

Fascicular involvement of the median nerve trunk in the upper arm is uncommon in cases of peripheral neuropathy, and its symptoms are consistent with those of anterior interosseous nerve (AIN) syndrome. We report three cases of focal anterior interosseous fascicular involvement in the median nerve trunk presenting as AIN palsy. Our report emphasizes the unique ultrasonographic and magnetic resonance imaging (MRI) features of swelling, hourglass-like constriction and torsion, and entwinement of the nerve fascicle of the dorsal region of the median nerve, which were confirmed surgically. Read More

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MicroCT optimisation for imaging fascicular anatomy in peripheral nerves.

J Neurosci Methods 2020 05 13;338:108652. Epub 2020 Mar 13.

EIT and Neurophysiology Lab, Medical Physics and Biomedical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom.

Background: Due to the lack of understanding of the fascicular organisation, vagus nerve stimulation (VNS) leads to unwanted off-target effects. Micro-computed tomography (microCT) can be used to trace fascicles from periphery and image fascicular anatomy.

New Method: In this study, we present a simple and reproducible method for imaging fascicles in peripheral nerves with iodine staining and microCT for the determination of fascicular anatomy and organisation. Read More

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Fascicle specific targeting for selective peripheral nerve stimulation.

J Neural Eng 2019 11 11;16(6):066040. Epub 2019 Nov 11.

Nerves Incorporated, Dallas TX, United States of America.

Objective: Electrical stimulation is a blunt tool for evoking neural activity. Neurons are naturally activated asynchronously and non-uniformly, whereas stimulation drives simultaneous activity within a population of cells. These differences in activation pattern can result in unintended side effects, including muddled sensory percepts and undesirable muscle contractions. Read More

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November 2019

Optimisation of bioimpedance measurements of neuronal activity with an ex vivo preparation of Cancer pagurus peripheral nerves.

J Neurosci Methods 2019 11 13;327:108322. Epub 2019 Aug 13.

EIT Group, Department of Medical Physics & Biomedical Engineering, University College London, WC1E 6BT, UK.

Background: In mammals, fast neural Electrical Impedance Tomography (EIT) can image the myelinated component of the compound action potentials (CAP) using a nerve cuff. If applied to unmyelinated fibres this has great potential to improve selective neuromodulation ("electroceuticals") to avoid off-target effects. Previously, bioimpedance recordings were averaged from unmyelinated crab leg nerve fibres, but the signal to noise ratio (SNR) needs improving. Read More

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November 2019

Avoiding off-target effects in electrical stimulation of the cervical vagus nerve: Neuroanatomical tracing techniques to study fascicular anatomy of the vagus nerve.

J Neurosci Methods 2019 09 28;325:108325. Epub 2019 Jun 28.

Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.

Vagus nerve stimulation (VNS) is a promising therapy for treatment of various conditions that are resistant to standard medication, such as heart failure, epilepsy, and depression. The vagus nerve is a complex nerve providing afferent and efferent innervation of the pharynx, larynx, heart, tracheobronchial tree and lungs, oesophagus, stomach, liver, pancreas, small intestine and proximal colon. It is therefore a prime target for intervention for VNS. Read More

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September 2019

The histologic spectrum of soft tissue spindle cell tumors with NTRK3 gene rearrangements.

Genes Chromosomes Cancer 2019 11 4;58(11):739-746. Epub 2019 Jun 4.

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.

NTRK3-rearranged tumors other than infantile fibrosarcomas (IFSs) harboring the canonical ETV6-NTRK3 fusions are uncommon, and include mainly inflammatory myofibroblastic tumors and gastrointestinal stromal tumors. Herein, we describe an additional subset of seven tumors sharing NTRK3 gene rearrangements. The cohort included five females and two males (age range 1-67 years). Read More

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November 2019

Bilateral idiopathic neuralgic amyotrophy involving selective branches of peripheral nerves with a stepwise progression: A case report.

Medicine (Baltimore) 2019 May;98(19):e15549

Department of Rehabilitation Medicine.

Rationale: This is a report about a rare case of idiopathic neuralgic amyotrophy (INA) involving selective peripheral nerve branches of bilateral upper extremities, which exhibited a stepwise progression.

Patient Concern: A 66-year-old woman presented with paresis of selective branches of bilateral median nerves, followed by paresis of bilateral posterior interosseous nerve (PIN) 8 weeks later.

Diagnoses: We diagnosed it as INA involving the selective motor branches of bilateral median nerves and bilateral PINs. Read More

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End-to-side Somatic-to-autonomic Nerve Grafting to Restore Erectile Function and Improve Quality of Life After Radical Prostatectomy.

Eur Urol 2019 08 5;76(2):189-196. Epub 2019 Apr 5.

Department of Surgery, The University of Melbourne, Parkville, Victoria, Australia; Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia; Southern Plastic Surgery, Brighton, Victoria, Australia. Electronic address:

Background: Radical prostatectomy (RP) is recommended for the treatment of men with clinically localised prostate cancer. However, RP is associated with a high incidence of erectile dysfunction (ED), which can impact the quality of life (QoL) significantly.

Objective: To evaluate the effectiveness of end-to-side nerve grafting surgery to restore erectile function and improve sexual QoL in men with ED after RP. Read More

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Reconstruction of the spinal accessory nerve with selective fascicular nerve transfer of the upper trunk.

J Neurosurg Spine 2019 04;31(1):133-138

1Christian Doppler Laboratory for Restoration of Extremity Function, Department of Surgery, Medical University of Vienna.

Objective: Spinal accessory nerve palsy is frequently caused by iatrogenic damage during neck surgery in the posterior triangle of the neck. Due to late presentation, treatment regularly necessitates nerve grafts, which often results in a poor outcome of trapezius function due to long regeneration distances. Here, the authors report a distal nerve transfer using fascicles of the upper trunk related to axillary nerve function for reinnervation of the trapezius muscle. Read More

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Hourglass-like constriction neuropathy of the suprascapular nerve detected by high-resolution magnetic resonance neurography: report of three patients.

Skeletal Radiol 2019 Sep 12;48(9):1451-1456. Epub 2019 Feb 12.

Department of Physical and Rehabilitation Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-Ro, Gangnam-gu, Seoul, 06351, South Korea.

Hourglass-like constriction neuropathy is a neurological condition caused by non-traumatic, non-compressive fascicular constrictions of one or more individual peripheral nerves. Based on clinical manifestations, it is very difficult to differentiate hourglass-like constriction neuropathy from idiopathic neuralgic amyotrophy. Focal hourglass-like constriction neuropathy may be erroneously diagnosed as idiopathic neuralgic amyotrophy. Read More

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September 2019

Decoding motor neuron activity from epimysial thin-film electrode recordings following targeted muscle reinnervation.

J Neural Eng 2019 02 1;16(1):016010. Epub 2018 Nov 1.

Department of Bioengineering, Imperial College London, London, United Kingdom.

Objective: Surface electromyography (EMG) is currently used as a control signal for active prostheses in amputees who underwent targeted muscle reinnervation (TMR) surgery. Recent research has shown that it is possible to access the spiking activity of spinal motor neurons from multi-channel surface EMG. In this study, we propose the use of multi-channel epimysial EMG electrodes as an interface for decoding motor neurons activity following TMR. Read More

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February 2019

Thin Film Multi-Electrode Softening Cuffs for Selective Neuromodulation.

Sci Rep 2018 11 6;8(1):16390. Epub 2018 Nov 6.

Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA.

Silicone nerve cuff electrodes are commonly implanted on relatively large and accessible somatic nerves as peripheral neural interfaces. While these cuff electrodes are soft (1-50 MPa), their self-closing mechanism requires of thick walls (200-600 µm), which in turn contribute to fibrotic tissue growth around and inside the device, compromising the neural interface. We report the use of thiol-ene/acrylate shape memory polymer (SMP) for the fabrication of thin film multi-electrode softening cuffs (MSC). Read More

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November 2018

Elimination of Purkinje Fibers by Electroporation Reduces Ventricular Fibrillation Vulnerability.

J Am Heart Assoc 2018 08;7(15):e009070

2 Division of Heart Rhythm Services Department of Cardiovascular Diseases Mayo Clinic Rochester MN.

Background The Purkinje network appears to play a pivotal role in the triggering as well as maintenance of ventricular fibrillation. Irreversible electroporation ( IRE ) using direct current has shown promise as a nonthermal ablation modality in the heart, but its ability to target and ablate the Purkinje tissue is undefined. Our aim was to investigate the potential for selective ablation of Purkinje/fascicular fibers using IRE . Read More

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Imaging fast neural traffic at fascicular level with electrical impedance tomography: proof of principle in rat sciatic nerve.

J Neural Eng 2018 10 2;15(5):056025. Epub 2018 Aug 2.

Department of Medical Physics, University College London, Gower Street, London WC1E 6BT, United Kingdom.

Objective: Understanding the coding of neural activity in nerve fascicles is a high priority in computational neuroscience, electroceutical autonomic nerve stimulation and functional electrical stimulation for treatment of paraplegia. Unfortunately, it has been little studied as no technique has yet been available to permit imaging of neuronal depolarization within fascicles in peripheral nerve.

Approach: We report a novel method for achieving this, using a flexible cylindrical multi-electrode cuff placed around nerve and the new medical imaging technique of fast neural electrical impedance tomography (EIT). Read More

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October 2018

The Role of Selective Peripheral Neurectomy in the Treatment of Upper Limb Spasticity.

J Hand Surg Asian Pac Vol 2018 Jun;23(2):181-191

* Departments of Plastic Surgery, Royal Hospital for Sick Children, Edinburgh, UK.

Background: Management of upper limb spasticity remains challenging. Selective peripheral neurectomy (SPN) is a relatively recent intervention for cases refractory to medical therapy. The aim of this study was to conduct a systematic review looking at the efficacy and outcomes of SPN, in order to clarify the patient selection criteria and surgical technique. Read More

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Left anterior descending coronary artery dissection during ventricular tachycardia ablation - case report.

Rom J Intern Med 2018 Mar;56(1):63-66

University Hospital Center Sisters of Charity, Department of Cardiology, Zagreb, Croatia.

Fascicular left ventricular tachycardia (VT) is the second most frequent idiopathic left VT in the setting of a structurally normal heart. Catheter ablation is curative in most patients with low complication rates. We report a case of ostial left anterior descending coronary artery (LAD) occlusion during fascicular ventricular tachycardia ablation. Read More

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Anatomical Ablation Strategy for Noninducible Fascicular Tachycardia.

Card Electrophysiol Clin 2016 Mar 8;8(1):115-20. Epub 2016 Jan 8.

Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan. Electronic address:

The presence of structural heart disease does not exclude fascicular ventricular tachycardia (VT), especially if the VT is verapamil sensitive. An empirical anatomic approach is effective when fascicular VT is noninducible or if diastolic Purkinje potential (P1) cannot be recorded during VT mapping. Pace mapping at the successful ablation site is usually not effective because selective pacing of P1 is difficult and there is an antidromic activation of the proximal P1 potential. Read More

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Fascicular Phrenic Nerve Neurotization for Restoring Physiological Motion in a Congenital Diaphragmatic Hernia Reconstruction With a Reverse Innervated Latissimus Dorsi Muscle Flap.

Ann Plast Surg 2015 Aug;75(2):193-6

From the *Department of Plastic, Reconstructive and Maxillo-Facial Surgery, and Burn Unit, and †Department of Pedriatics and Pedriatic Surgery, Centro Hospitalar de São João, Porto, Portugal.

Congenital diaphragmatic hernia is a severe developmental anomaly characterized by the malformation of the diaphragm. An innervated reversed latissimus dorsi flap reconstruction for recurrent congenital diaphragmatic hernia has been described as an alternative to prosthetic patch repair to achieve pleuroperitoneal separation. However, there is very little supporting scientific data; therefore, there is no real basic understanding of the condition of the phrenic nerve in the absence of diaphragmatic muscle or even the neurotization options for restoring neodiaphragmatic muscle motion. Read More

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Spatial and Functional Selectivity of Peripheral Nerve Signal Recording With the Transversal Intrafascicular Multichannel Electrode (TIME).

IEEE Trans Neural Syst Rehabil Eng 2016 Jan 15;24(1):20-7. Epub 2015 Jun 15.

The selection of suitable peripheral nerve electrodes for biomedical applications implies a trade-off between invasiveness and selectivity. The optimal design should provide the highest selectivity for targeting a large number of nerve fascicles with the least invasiveness and potential damage to the nerve. The transverse intrafascicular multichannel electrode (TIME), transversally inserted in the peripheral nerve, has been shown to be useful for the selective activation of subsets of axons, both at inter- and intra-fascicular levels, in the small sciatic nerve of the rat. Read More

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January 2016

Neuralgic amyotrophy manifested by severe axillary mononeuropathy limited only to the anterior branch.

Muscle Nerve 2015 Jul 5;52(1):143-5. Epub 2015 Mar 5.

Department Neurology, Walter Reed National Military Medical Center, 8901 Wisconsin Avenue, Bethesda, Maryland, 20815, USA.

Introduction: In this study we describe a case demonstrating clinical, radiographic, electrophysiologic, and surgical evidence of a restricted but severe anterior branch axillary nerve mononeuropathy due to neuralgic amyotrophy (NA).

Methods: On each diagnostic modality there was severe involvement of the anterior and lateral deltoid muscle with sparing of the posterior deltoid and teres minor muscles and cutaneous innervation to the skin overlying the lateral shoulder.

Results: No structural etiologies were discovered during surgical exploration. Read More

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Immunohistochemical, ultrastructural and functional analysis of axonal regeneration through peripheral nerve grafts containing Schwann cells expressing BDNF, CNTF or NT3.

PLoS One 2013 9;8(8):e69987. Epub 2013 Aug 9.

School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia.

We used morphological, immunohistochemical and functional assessments to determine the impact of genetically-modified peripheral nerve (PN) grafts on axonal regeneration after injury. Grafts were assembled from acellular nerve sheaths repopulated ex vivo with Schwann cells (SCs) modified to express brain-derived neurotrophic factor (BDNF), a secretable form of ciliary neurotrophic factor (CNTF), or neurotrophin-3 (NT3). Grafts were used to repair unilateral 1 cm defects in rat peroneal nerves and 10 weeks later outcomes were compared to normal nerves and various controls: autografts, acellular grafts and grafts with unmodified SCs. Read More

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