The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Hubertus Axer - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound of the Peripheral Nerves in systemic vasculitic neuropathies
Journal of the Neurological Sciences, 2014Co-Authors: Alexander Grimm, Bernhard F. Décard, Antje Bischof, Hubertus AxerAbstract:INTRODUCTION: Ultrasound of the Peripheral Nerves (PNUS) can be used to visualize nerve pathologies in polyneuropathies (PNP). The aim of this study was to investigate, whether PNUS provides additional information in patients with proven systemic vasculitic neuropathies (VN). MATERIAL AND METHODS: Systematic ultrasound measurements of several Peripheral Nerves, the vagal nerve and the 6th cervical nerve root were performed in 14 patients and 22 healthy controls. Nerve conduction studies of the corresponding Nerves were undertaken. Finally, the measured results were compared to a study population of demyelinating immune-mediated and axonal neuropathies. RESULTS: Patients with VN displayed significant smaller amplitudes of compound muscle action potentials (CMAP) (p
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ultrasound of the Peripheral Nerves in systemic vasculitic neuropathies
Journal of the Neurological Sciences, 2014Co-Authors: Alexander Grimm, Bernhard F. Décard, Antje Bischof, Hubertus AxerAbstract:INTRODUCTION: Ultrasound of the Peripheral Nerves (PNUS) can be used to visualize nerve pathologies in polyneuropathies (PNP). The aim of this study was to investigate, whether PNUS provides additional information in patients with proven systemic vasculitic neuropathies (VN). MATERIAL AND METHODS: Systematic ultrasound measurements of several Peripheral Nerves, the vagal nerve and the 6th cervical nerve root were performed in 14 patients and 22 healthy controls. Nerve conduction studies of the corresponding Nerves were undertaken. Finally, the measured results were compared to a study population of demyelinating immune-mediated and axonal neuropathies. RESULTS: Patients with VN displayed significant smaller amplitudes of compound muscle action potentials (CMAP) (p<0.05) and sensory nerve action potentials (SNAP) compared to healthy controls, while conduction velocity did not differ between groups. The mean nerve cross-sectional areas (CSA) were increased in several Peripheral Nerves compared to the controls, most prominent in tibial and fibular nerve (p<0.01). PNUS revealed nerve enlargement in most of the clinically and electrophysiologically affected Nerves (22 out of 31) in VN. Nerve enlargement was more often seen in vasculitic neuropathies than in other axonal neuropathies, but significantly rarer than in demyelinating neuropathies. CONCLUSION: Focal CSA enlargement in one or more Nerves in electrophysiologically axonal neuropathies can be a hint for VN and thus facilitate diagnostic and therapeutic procedures.
Stefano Bianchi - One of the best experts on this subject based on the ideXlab platform.
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ultrasound of the Peripheral Nerves
Joint Bone Spine, 2008Co-Authors: Stefano BianchiAbstract:Abstract Peripheral Nerves disorders are common in the rheumatologic practice and can mimic a variety of musculoskeletal diseases. Clinical evaluation remains the mainstay for diagnosing nerve disorders of the extremities. A careful history and an accurate physical examination lead in most patients to a high diagnostic suspicion. Nevertheless several imaging techniques are usually obtained to confirm the clinical data and in the preoperative workup. Although standard radiographs and computed tomography do not visualize the Nerves directly, they can reveal the adjacent anatomic structures such as bones and joints and can add additional information that frequently is essential in the choice of adequate treatment. Magnetic resonance imaging and ultrasound show Peripheral Nerves directly and can reveal their size and internal structure. With the new developments in high resolution, electronic broadband transducers, ultrasound (US) is now considered an optimal imaging technique to evaluate the normal anatomy and disorders of Peripheral Nerves. Well recognized advantages of this technique in this field are: the possibility of realizing a dynamic examination and assessing long Nerves segments in a short time; it is non-invasive and low cost. In addition US is better accepted by the patients. In this article we present a brief description of the normal and US anatomy of the Peripheral Nerves followed by a description of the US appearance of the most frequent disorders: entrapment neuropathies (EN), tumor and cystic lesions.
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ultrasonography of Peripheral Nerves
Seminars in Ultrasound Ct and Mri, 2000Co-Authors: Carlo Martinoli, Stefano Bianchi, Lorenzo E. DerchiAbstract:Abstract With recent improvements in ultrasound (US) imaging equipment and refinements in scanning technique, an increasing number of Peripheral Nerves and related pathologic conditions can be identified. US imaging can support clinical and electrophysiologic testing for detection of nerve abnormalities caused by trauma, tumors, and a variety of nonneoplastic conditions, including entrapment neuropathies. This article addresses the normal US appearance of Peripheral Nerves and discusses the potential role of US nerve imaging in specific clinical settings. A series of US images of diverse pathologic processes involving Peripheral Nerves is presented.
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Ultrasonography of Peripheral Nerves.
Journal of The Peripheral Nervous System, 1996Co-Authors: Carlo Martinoli, Giovanni Serafini, Stefano Bianchi, Bertolotto M, N. Gandolfo, Lorenzo E. DerchiAbstract:: During sonographic examination of the extremities using high frequency "small-parts" equipment, Peripheral Nerves may be identified in virtually all patients. Peripheral Nerves have a typical ultrasonographic pattern that correlates well with histologic structure and facilitates differentiation between Nerves and tendons. The ability of this technique to depict Peripheral Nerves makes it possible, in many instances, to study nerve abnormalities in trauma, entrapment syndromes and tumors. Ultrasound can enable differentiation of an endoneural from an extraneural space-occupying lesion and evaluation of the extent and consistency of the lesion, as well as the integrity and dynamic behavior of the nerve involved at follow-up study. The purpose of this review article is to describe the normal ultrasonographic appearance of Peripheral Nerves and to discuss the potential role of this technique to image nerve lesions noninvasively. A series of paradigmatic ultrasound images of diverse pathologic processes involving Peripheral Nerves is presented. Although the ultrasound study of Peripheral Nerves remains in its infancy, with further refinement of ultrasound technology and a more precise knowledge of the ultrasound appearance of the extremities we may be optimistic to the future impact of this technique on diagnosis, treatment and prognosis in patients clinically suspected to have a nerve lesion.
Jaana Hiltunen - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imaging and tractography of distal Peripheral Nerves at 3 t
Clinical Neurophysiology, 2005Co-Authors: Jaana Hiltunen, Taru Suortti, Sakari Arvela, Mika Seppa, Raimo Joensuu, Riitta HariAbstract:Objective: We studied whether distal Peripheral Nerves could be imaged using quantitative diffusion tensor imaging (DTI) with a 3-T MRI scanner, and visualized using tractography. Methods: Altogether 6 healthy subjects were studied. The diffusion was quantified with apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps, and the direction of main diffusivity was visualized with color-coded orientation maps and tractography. Results: We present the first DTI and tractography results of human distal Peripheral Nerves. The courses of median, ulnar, and radial Nerves in the upper limb and of tibial and peroneal Nerves in the lower limb were first analyzed quantifying ADC and FA, and then visualized in 3D with tractography. Tractography illustrated nicely the 3D courses of both upper and lower limb Nerves which were reliably distinguished from the surrounding muscle tissue and ligaments. Conclusions: Quantitative DTI and tractography can be used to image and visualize distal Peripheral Nerves. Significance: DTI is a quantitative method that could provide useful information for the diagnosis and follow-up of nerve lesions, entrapments, and regeneration. Peripheral Nerves as well-delineated structures also containing abundant branching into bundles of different diameters, could be used as ‘living phantoms’ for testing and validating different tractography methods.
Alexander Grimm - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound of the Peripheral Nerves in systemic vasculitic neuropathies
Journal of the Neurological Sciences, 2014Co-Authors: Alexander Grimm, Bernhard F. Décard, Antje Bischof, Hubertus AxerAbstract:INTRODUCTION: Ultrasound of the Peripheral Nerves (PNUS) can be used to visualize nerve pathologies in polyneuropathies (PNP). The aim of this study was to investigate, whether PNUS provides additional information in patients with proven systemic vasculitic neuropathies (VN). MATERIAL AND METHODS: Systematic ultrasound measurements of several Peripheral Nerves, the vagal nerve and the 6th cervical nerve root were performed in 14 patients and 22 healthy controls. Nerve conduction studies of the corresponding Nerves were undertaken. Finally, the measured results were compared to a study population of demyelinating immune-mediated and axonal neuropathies. RESULTS: Patients with VN displayed significant smaller amplitudes of compound muscle action potentials (CMAP) (p
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ultrasound of the Peripheral Nerves in systemic vasculitic neuropathies
Journal of the Neurological Sciences, 2014Co-Authors: Alexander Grimm, Bernhard F. Décard, Antje Bischof, Hubertus AxerAbstract:INTRODUCTION: Ultrasound of the Peripheral Nerves (PNUS) can be used to visualize nerve pathologies in polyneuropathies (PNP). The aim of this study was to investigate, whether PNUS provides additional information in patients with proven systemic vasculitic neuropathies (VN). MATERIAL AND METHODS: Systematic ultrasound measurements of several Peripheral Nerves, the vagal nerve and the 6th cervical nerve root were performed in 14 patients and 22 healthy controls. Nerve conduction studies of the corresponding Nerves were undertaken. Finally, the measured results were compared to a study population of demyelinating immune-mediated and axonal neuropathies. RESULTS: Patients with VN displayed significant smaller amplitudes of compound muscle action potentials (CMAP) (p<0.05) and sensory nerve action potentials (SNAP) compared to healthy controls, while conduction velocity did not differ between groups. The mean nerve cross-sectional areas (CSA) were increased in several Peripheral Nerves compared to the controls, most prominent in tibial and fibular nerve (p<0.01). PNUS revealed nerve enlargement in most of the clinically and electrophysiologically affected Nerves (22 out of 31) in VN. Nerve enlargement was more often seen in vasculitic neuropathies than in other axonal neuropathies, but significantly rarer than in demyelinating neuropathies. CONCLUSION: Focal CSA enlargement in one or more Nerves in electrophysiologically axonal neuropathies can be a hint for VN and thus facilitate diagnostic and therapeutic procedures.
Riitta Hari - One of the best experts on this subject based on the ideXlab platform.
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diffusion tensor imaging and tractography of distal Peripheral Nerves at 3 t
Clinical Neurophysiology, 2005Co-Authors: Jaana Hiltunen, Taru Suortti, Sakari Arvela, Mika Seppa, Raimo Joensuu, Riitta HariAbstract:Objective: We studied whether distal Peripheral Nerves could be imaged using quantitative diffusion tensor imaging (DTI) with a 3-T MRI scanner, and visualized using tractography. Methods: Altogether 6 healthy subjects were studied. The diffusion was quantified with apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps, and the direction of main diffusivity was visualized with color-coded orientation maps and tractography. Results: We present the first DTI and tractography results of human distal Peripheral Nerves. The courses of median, ulnar, and radial Nerves in the upper limb and of tibial and peroneal Nerves in the lower limb were first analyzed quantifying ADC and FA, and then visualized in 3D with tractography. Tractography illustrated nicely the 3D courses of both upper and lower limb Nerves which were reliably distinguished from the surrounding muscle tissue and ligaments. Conclusions: Quantitative DTI and tractography can be used to image and visualize distal Peripheral Nerves. Significance: DTI is a quantitative method that could provide useful information for the diagnosis and follow-up of nerve lesions, entrapments, and regeneration. Peripheral Nerves as well-delineated structures also containing abundant branching into bundles of different diameters, could be used as ‘living phantoms’ for testing and validating different tractography methods.
