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Sample records for nerve head blood

  1. Laser Doppler measurement of relative blood velocity in the human optic nerve head

    SciTech Connect

    Riva, C.E.; Grunwald, J.E.; Sinclair, S.H.

    1982-02-01

    The Doppler shift frequency spectrum (DSFS) of laser light scattered from red blood cells (RBCs) moving in the microcirculation of the optic nerve head has been recorded in normal volunteers by means of a fundus camera laser Doppler velocimeter. The width of the DSFS, which varies in proportion to the speed of the RBCs, has been characterized by a parameter alpha. With the use of a model for the scattering of light by tissue and RBCs and for the RBC velocity distribution, values of alpha recorded at normal intraocular pressure (IOP) suggest that the RBCs that contribute to the Doppler signal are flowing in capillaries. The parameter alpha was found to vary markedly with the IOP and with the phase of the ocular pressure pulse at elevated IOP. The return of the speed of RBCs toward normal, which is observed after a step increase of IOP above normal and after a step decrease below normal, has been attributed to an autoregulatory response of the optic nerve circulation.

  2. Breakdown of the normal optic nerve head blood-brain barrier following acute elevation of intraocular pressure in experimental animals.

    PubMed

    Radius, R L; Anderson, D R

    1980-03-01

    Five hours of elevated intraocular pressure produced evidence of an altered blood-brain barrier at the optic nerve head in 27 of 29 monkey eyes. The change in vascular permeability was documented by fluorescein angiography (18 of 21 eyes), by Evans blue fluorescence microscopy (21 of 23 eyes), or by both methods. Leakage occurred from major blood vessels as well as from microvasculature of the nerve head. In 22 eyes, rapid axonal transport was studied after intravitreal injection of tritiated leucine. In 18 of these 22 eyes, autoradiography demonstrated a local interruption of axonal transport. In 15 eyes examined by all three methods, leakage from microvasculature (as opposed to leakage from the major vessels) was loosely associated with severe and widespread blockade of axonal transport at the lamina cribrosa. Although cause-and-effect relationships are not proved, ischemia may be responsible both for the focal endothelial damage with breakdown of the normal blood-brain barrier and for the local abnormalities of axonal transport.

  3. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    NASA Astrophysics Data System (ADS)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  4. Impact of intraocular pressure on changes of blood flow in the retina, choroid, and optic nerve head in rats investigated by optical microangiography.

    PubMed

    Zhi, Zhongwei; Cepurna, William O; Johnson, Elaine C; Morrison, John C; Wang, Ruikang K

    2012-09-01

    In this paper, we demonstrate the use of optical coherence tomography/optical microangiography (OCT/OMAG) to image and measure the effects of acute intraocular pressure (IOP) elevation on retinal, choroidal and optic nerve head (ONH) perfusion in the rat eye. In the experiments, IOP was elevated from 10 to 100 mmHg in 10 mmHg increments. At each IOP level, three-dimensional data volumes were captured using an ultrahigh sensitive (UHS) OMAG scanning protocol for 3D volumetric perfusion imaging, followed by repeated B-scans for Doppler OMAG analysis to determine blood flow velocity. Velocity and vessel diameter measurements were used to calculate blood flow in selected retinal blood vessels. Choroidal perfusion was calculated by determining the peripapillary choroidal filling at each pressure level and calculating this as a percentage of area filling at baseline (10 mmHg). ONH blood perfusion was calculated as the percentage of blood flow area over a segmented ONH area to a depth 150 microns posterior to the choroidal opening. We show that volumetric blood flow reconstructions revealed detailed 3D maps, to the capillary level, of the retinal, choroidal and ONH microvasculature, revealing retinal arterioles, capillaries and veins, the choroidal opening and a consistent presence of the central retinal artery inferior to the ONH. While OCT structural images revealed a reversible compression of the ONH and vasculature with elevated IOP, OMAG successfully documented changes in retinal, choroidal and ONH blood perfusion and allowed quantitative measurements of these changes. Starting from 30 mm Hg, retinal blood flow (RBF) diminished linearly with increasing IOP and was nearly extinguished at 100 mm Hg, with full recovery after return of IOP to baseline. Choroidal filling was unaffected until IOP reached 60 mmHg, then decreased to 20% of baseline at IOP 100 mmHg, and normalized when IOP returned to baseline. A reduction in ONH blood perfusion at higher IOP's was also

  5. Hyperemic responses of the optic nerve head blood flow to chromatic equiluminant flicker are reduced by ocular hypertension and early glaucoma

    NASA Astrophysics Data System (ADS)

    Falsini, Benedetto; Riva, Charles E.; Salgarello, Tommaso; Logean, Eric; Colotto, Alberto; Giudiceandrea, Andrea

    2014-06-01

    We evaluated in ocular hypertension (OHT) and early glaucoma (EOAG) patients the optic nerve head (ONH) blood flow response (RF) to chromatic equiluminant flicker. This stimulus generates neural activity dominated by the parvo-cellular system. Eleven EOAG, 20 OHT patients, and 8 age-matched control subjects were examined. The blood flow (F) at the neuroretinal rim was continuously monitored by laser Doppler flowmetry before, during, and after a 60-s exposure to a 4 Hz, red-green equiluminant flicker stimulus (30 deg field). RF was expressed as percentage F-change during the last 20 s of flicker relative to baseline F. Responses were collected at a number of temporal sites. The highest RF value was used for subsequent analysis. As compared to controls, both OHT and EOAG patients showed a decrease (p<0.01) in mean RF. We conclude that RF elicited by chromatic equiluminant flicker is abnormally reduced in OHT and EOAG patients indicating an impairment of the parvo-cellular-mediated vasoactivity. This decrease of vascular response may occur independently of neural activity loss early in the disease process.

  6. Radial head fracture associated with posterior interosseous nerve injury.

    PubMed

    Terra, Bernardo Barcellos; Sassine, Tannus Jorge; Lima, Guilherme de Freitas; Rodrigues, Leandro Marano; Padua, David Victoria Hoffmann; Nadai, Anderson de

    2016-01-01

    Fractures of the radial head and radial neck correspond to 1.7-5.4% of all fractures and approximately 30% may present associated injuries. In the literature, there are few reports of radial head fracture with posterior interosseous nerve injury. This study aimed to report a case of radial head fracture associated with posterior interosseous nerve injury.

  7. Optic nerve head biomechanics in aging and disease.

    PubMed

    Downs, J Crawford

    2015-04-01

    This nontechnical review is focused upon educating the reader on optic nerve head biomechanics in both aging and disease along two main themes: what is known about how mechanical forces and the resulting deformations are distributed in the posterior pole and ONH (biomechanics) and what is known about how the living system responds to those deformations (mechanobiology). We focus on how ONH responds to IOP elevations as a structural system, insofar as the acute mechanical response of the lamina cribrosa is confounded with the responses of the peripapillary sclera, prelaminar neural tissues, and retrolaminar optic nerve. We discuss the biomechanical basis for IOP-driven changes in connective tissues, blood flow, and cellular responses. We use glaucoma as the primary framework to present the important aspects of ONH biomechanics in aging and disease, as ONH biomechanics, aging, and the posterior pole extracellular matrix (ECM) are thought to be centrally involved in glaucoma susceptibility, onset and progression.

  8. Anatomy of the optic nerve head and glaucomatous optic neuropathy.

    PubMed

    Radius, R L

    1987-01-01

    The mechanism of axon damage in eyes with glaucomatous optic neuropathy remains undefined. Interestingly, it has been observed that, although the entire nerve cross-section may be involved by the nerve damage, in many instances, the superior and inferior axon bundles are preferentially affected by the pressure insult. Thus, recent studies by many investigators have stressed a re-examination of the optic nerve head anatomy, including the nerve head microcirculation, the glial and connective tissue elements within the nerve head, and the morphology of the axons themselves. Any correlation between regional differences in this anatomy and the preferential involvement by specific axon bundles within the nerve head by the pressure insult may suggest some further insight into the mechanisms underlying the pressure-induced axon loss in glaucomatous eyes.

  9. Delayed and isolated oculomotor nerve palsy following minor head trauma

    PubMed Central

    Nakagawa, Yu; Toda, Masahiro; Shibao, Shunsuke; Yoshida, Kazunari

    2017-01-01

    Background: The purpose of this study was to consider the mechanism of isolated oculomotor nerve palsy after minor head trauma. Case Description: We report a rare case of delayed and isolated oculomotor nerve palsy following minor head trauma. A 19-year-old boy complained of double vision 1 day after a minor head trauma. Neuro-ophthalmic examination showed isolated left oculomotor nerve palsy. Computed tomography and magnetic resonance imaging examination revealed no abnormal findings and steroid therapy was administered for a week. Three months after the injury, the ptosis and extraocular movements had fully resolved, although the pupillary light reflex was still abnormal. Conclusions: Delayed and isolated oculomotor nerve palsy may be caused by an injury at the point where the oculomotor nerve runs over the posterior petroclinoid ligament. Because edema of the damaged oculomotor nerve might result in constriction at the point where the nerve pierces the dura of the cavernous sinus, symptoms of oculomotor nerve palsy appeared late after trauma. Steroid treatment reducing edema could be effective for delayed and isolated oculomotor nerve palsy following minor head trauma. PMID:28217399

  10. Evaluation of the Optic Nerve Head in Glaucoma.

    PubMed

    Gandhi, Monica; Dubey, Suneeta

    2013-01-01

    Glaucoma is an optic neuropathy leading to changes in the intrapaillary and parapaillary regions of the optic disk. Despite technological advances, clinical identification of optic nerve head characteristics remains the first step in diagnosis. Careful examination of the disk parameters including size, shape, neuroretinal rim shape and pallor; size of the optic cup in relation to the area of the disk; configuration and depth of the optic cup; ratios of cup-to-disk diameter and cup-to-disk area; presence and location of splinter-shaped hemorrhages; occurrence, size, configuration, and location of parapapillary chorioretinal atrophy; and visibility of the retinal nerve fiber layer (RNFL) is important to differentiate between the glaucomatous and nonglaucomatous optic neuropathy. How to cite this article: Gandhi M, Dubey S. Evaluation of the Optic Nerve Head in Glaucoma. J Current Glau Prac 2013;7(3):106-114.

  11. Oxygen saturation changes in the optic nerve head during acute intraocular pressure elevation in monkeys

    NASA Astrophysics Data System (ADS)

    Khoobehi, Bahram; Kawano, Hiroyuki; Ning, Jinfeng; Burgoyne, Claude F.; Rice, David A.; Khan, Fareeha; Thompson, Hilary W.; Beach, James M.

    2009-02-01

    Background and Objective: To evaluate the effect of an acute elevated intraocular pressure (IOP) on oxygen saturation of structures of the optic nerve head. Study Design/Materials and Methods: In the cynomolgus monkey eye, IOP was set to 10 mm Hg, and then raised to 30, 45, and 55 mm Hg. The ONH and overlying vessels were imaged using a fundus camera attached to a hyperspectral imaging system (HSI) at 10 and 30 minutes after IOP elevation. Results: Raising IOP from 10 to 30 mm Hg did not significantly (P < 0.0001) change saturation in vessels or ONH tissue structures but at 55 mm Hg, all structures showed significant reduction. Conclusions: Quantitative assay of the blood oxygen saturation in structures on the surface and overlying the optic nerve head is possible using hyperspectral imaging techniques.

  12. Measuring Mean Cup Depth in the Optic Nerve Head

    PubMed Central

    Johnstone, John K.; Rhodes, Lindsay; Fazio, Massimo; Smith, Brandon; Wang, Lan; Downs, J. Crawford; Owsley, Cynthia; Girkin, Christopher A.

    2016-01-01

    Since the deformation of structures in the optic nerve head (ONH) is associated with glaucoma and other diseases of the optic nerve, measurement of this deformation is of current research interest. This paper considers the computation of cup depth, a measurement of the depth of the internal limiting membrane (ILM). The computation of cup depth requires a reference structure against which to measure the ILM, and the construction of two reference structures is discussed, one based on Bruch's membrane opening (BMO) and the other based on the anterior surface of the peripapillary sclera (AS). A main focus of the paper is the robust computation of mean cup depth, which requires a good sampling of a reconstruction of the ILM surface. To evaluate our algorithm, the construction of synthetic datasets is considered. PMID:27942258

  13. Angiogram, fundus, and oxygen saturation optic nerve head image fusion

    NASA Astrophysics Data System (ADS)

    Cao, Hua; Khoobehi, Bahram

    2009-02-01

    A novel multi-modality optic nerve head image fusion approach has been successfully designed. The new approach has been applied on three ophthalmologic modalities: angiogram, fundus, and oxygen saturation retinal optic nerve head images. It has achieved an excellent result by giving the visualization of fundus or oxygen saturation images with a complete angiogram overlay. During this study, two contributions have been made in terms of novelty, efficiency, and accuracy. The first contribution is the automated control point detection algorithm for multi-sensor images. The new method employs retina vasculature and bifurcation features by identifying the initial good-guess of control points using the Adaptive Exploratory Algorithm. The second contribution is the heuristic optimization fusion algorithm. In order to maximize the objective function (Mutual-Pixel-Count), the iteration algorithm adjusts the initial guess of the control points at the sub-pixel level. A refinement of the parameter set is obtained at the end of each loop, and finally an optimal fused image is generated at the end of the iteration. It is the first time that Mutual-Pixel-Count concept has been introduced into biomedical image fusion area. By locking the images in one place, the fused image allows ophthalmologists to match the same eye over time and get a sense of disease progress and pinpoint surgical tools. The new algorithm can be easily expanded to human or animals' 3D eye, brain, or body image registration and fusion.

  14. The connective tissue and glial framework in the optic nerve head of the normal human eye: light and scanning electron microscopic studies.

    PubMed

    Oyama, Tokuhide; Abe, Haruki; Ushiki, Tatsuo

    2006-12-01

    The arrangement of connective tissue components (i.e., collagen, reticular, and elastic fibers) and glial elements in the optic nerve head of the human eye was investigated by the combined use of light microscopy and scanning electron microscopy (SEM). Light-microscopically, the optic nerve head could be subdivided into four parts from the different arrangements of the connective tissue framework: a surface nerve fiber layer, and prelaminar, laminar, and postlaminar regions. The surface nerve fiber layer only possessed connective tissue elements around blood vessels. In the prelaminar region, collagen fibrils, together with delicate elastic fibers, formed thin interrupted sheaths for accommodating small nerve bundles. Immunohistochemistry for the glial fibrillary acidic protein (GFAP) showed that GFAP-positive cells formed columnar structures (i.e., glial columns), with round cell bodies piled up into layers. These glial columns were located in the fibrous sheaths of collagen fibrils and elastic fibers. In the laminar region, collagen fibrils and elastic fibers ran transversely to the optic nerve axis to form a thick membranous layer - the lamina cribrosa - which had numerous round openings for accommodating optic nerve fiber bundles. GFAP-positive cellular processes also ran transversely in association with collagen and elastin components. The postlaminar region had connective tissues which linked the lamina cribrosa with fibrous sheaths for accommodating nerve bundles in the extraocular optic nerve, where GFAP-positive cells acquired characteristics typical of fibrous astrocytes. These findings indicate that collagen fibrils, as a whole, form a continuous network which serves as a skeletal framework of the optic nerve head for protecting optic nerve fibers from mechanical stress as well as for sustaining blood vessels in the optic nerve. The lamina cribrosa containing elastic fibers are considered to be plastic against the mechanical force affected by elevation

  15. Intracranial Pressure Influences the Behavior of the Optic Nerve Head.

    PubMed

    Hua, Yi; Tong, Junfei; Ghate, Deepta; Kedar, Sachin; Gu, Linxia

    2017-03-01

    In this work, the biomechanical responses of the optic nerve head (ONH) to acute elevations in intracranial pressure (ICP) were systematically investigated through numerical modeling. An orthogonal experimental design was developed to quantify the influence of ten input factors that govern the anatomy and material properties of the ONH on the peak maximum principal strain (MPS) in the lamina cribrosa (LC) and postlaminar neural tissue (PLNT). Results showed that the sensitivity of ONH responses to various input factors was region-specific. In the LC, the peak MPS was most strongly dependent on the sclera thickness, LC modulus, and scleral canal size, whereas in the PLNT, the peak MPS was more sensitive to the scleral canal size, neural tissue modulus, and pia mater modulus. The enforcement of clinically relevant ICP in the retro-orbital subarachnoid space influenced the sensitivity analysis. It also induced much larger strains in the PLNT than in the LC. Moreover, acute elevation of ICP leads to dramatic strain distribution changes in the PLNT, but had minimal impact on the LC. This work could help to better understand patient-specific responses, to provide guidance on biomechanical factors resulting in optic nerve diseases, such as glaucoma, papilledema, and ischemic optic neuropathy, and to illuminate the possibilities for exploiting their potential to treat and prevent ONH diseases.

  16. Pit-like changes of the optic nerve head in open-angle glaucoma.

    PubMed Central

    Radius, R. L.; Maumenee, A. E.; Green, W. R.

    1978-01-01

    Six patients with open-angle glaucoma and acquired pit-like changes in the optic nerve head are presented. In 1 patient evolution of the pit-like defect is documented. In all 6 patients progression of associated visual field deficits is described. It is suggested that such pit-like changes in selected patients with glaucoma may not represent congenital lesions but rather local, progressive nerve head disease, occurring particularly in response to raised intraocular pressure. The management of patients with optic nerve head pitting and the pathogenesis of glaucomatous optic neuropathy are discussed with respect to this observation. Images PMID:666988

  17. Clinicopathologic correlation of retinal to choroidal venous collaterals of the optic nerve head.

    PubMed

    Schatz, H; Green, W R; Talamo, J H; Hoyt, W F; Johnson, R N; McDonald, H R

    1991-08-01

    An optic nerve meningioma developed in an elderly woman and was followed for 13 years until her death. The optic nerve was initially normal. Over time it became swollen and then atrophic and developed retinal venous to choroidal venous collaterals. Five hundred serial sections were prepared through the optic nerve and for approximately 1.5 mm superiorly and inferiorly to the optic nerve to trace the course of the collaterals that were seen ophthalmoscopically and angiographically in the optic nerve head. This clinicopathologic study shows clearly that the abnormal channels are, in fact, retinal venous to choroidal venous collaterals (bypass channels). Four collaterals extended around the end of Bruch's membrane at the optic nerve head. Two more collaterals extended through the retinal pigment epithelium to become continuous with a subretinal pigment epithelial neovascular membrane, the vessels of which connected with the choroidal vessels through a defect in Bruch's membrane.

  18. Muscle sympathetic nerve activity in blood pressure control against gravitational stress.

    PubMed

    Mano, T

    2001-10-01

    Muscle sympathetic nerve activity (MSNA) can be directly recorded from human peripheral nerves in situ using microneurography. MSNA plays an essential role to control systemic blood pressure against gravitational stress. MSNA was enhanced by changing posture against terrestrial gravity from lying to sitting, and from sitting to standing. This activity was enhanced by head-up tilt depending on the gravitational input from the head to the leg (+Gz) in the human body. Orthostatic hypotension occurred when MSNA response to gravitational stress was impaired both in high and low responders of this sympathetic outflow. Syncope was preceded and/or associated by a withdrawal of MSNA. MSNA was suppressed by short-term exposure to microgravity but was enhanced after long-term exposure to microgravity. Orthostatic intolerance after exposure to prolonged microgravity was associated with a reduction of increased MSNA response to gravitational stress. Aging influenced gravity-related responses of MSNA.

  19. Astrocytes in the Optic Nerve Head of Glaucomatous Mice Display a Characteristic Reactive Phenotype

    PubMed Central

    Wang, Rui; Seifert, Philip; Jakobs, Tatjana C.

    2017-01-01

    Purpose Optic nerve head astrocytes, a subtype of white-matter astrocytes, become reactive early in the course of glaucoma. It was shown recently that in the DBA/2J mouse model of inherited glaucoma optic nerve astrocytes extend new longitudinal processes into the axon bundles before ganglion cell loss becomes apparent. The present study aims at testing whether this behavior of astrocytes is typical of early glaucomatous damage. Methods Mice expressing green fluorescent protein in individual astrocytes were used to evaluate the early response of astrocytes in the glial lamina of the optic nerve head after increasing the IOP using the microbead occlusion method. Tissue sections from the glial lamina were imaged consecutively by confocal and electron microscopy. Results Confocal and electron microscope images show that astrocytes close to the myelination transition zone in the hypertensive nerve heads extend new processes that follow the longitudinal axis of the optic nerve and invade axon bundles in the nerve head. Ultrastructurally, the longitudinal processes were largely devoid of subcellular organelles except for degenerating mitochondria. Conclusions The longitudinal processes are a common feature of glaucomatous optic nerve astrocytes, whereas they are not observed after traumatic nerve injury. Thus, astrocytes appear to fine-tune their responses to the nature and/or timing of the injury to the neurons that they surround. PMID:28170536

  20. Dr. Henry Head and lessons learned from his self-experiment on radial nerve transection.

    PubMed

    Lenfest, Stephen M; Vaduva-Nemes, Andreea; Okun, Michael S

    2011-02-01

    In this paper the authors aim to review Dr. Henry Head's famous and dramatic nerve sectioning experiment. They discuss the implications of his experimental approach as well as the effect his experiment had on the field of neurology. Henry Head was a prominent British neurologist who contributed greatly to the understanding of the sensory examination through an experiment in which he had his own radial nerve transected. Head carefully documented the sensory changes following the sectioning. He hypothesized the existence of two separate sensory systems: protopathic and epicritic. Head was one of the first scientists to speculate on sensory dissociation, and his writings generated both enthusiasm and controversy. Although the ethical issue of self-experimentation was raised by his bold experiment and many aspects of his investigations and conclusions have been criticized, Head undoubtedly contributed important clinical lessons to neurology. Arguably, Henry Head's greatest contribution was the realization that the neurological portion of the sensory examination was anything but straightforward.

  1. [Blood circulation of cauda equina and nerve root].

    PubMed

    Kobayashi, Shigeru; Baba, Hisatoshi; Uchida, Kenzo; Kokubo, Yasuo; Yayama, Takafumi; Takeno, Kenichi; Negoro, Kohei

    2005-03-01

    It is generally considered that the genesis of radiculopathy associated with pathologic conditions of the spine, such as lumbar disc herniaton and lumbarl canal stenosis, may result from both mechanical compression and vascular problems. In this article, we have reviewed about the blood circulation of cauda equina and nerve root under normal and pathologic conditions.

  2. Optic nerve head and fibre layer imaging for diagnosing glaucoma

    PubMed Central

    Michelessi, Manuele; Lucenteforte, Ersilia; Oddone, Francesco; Brazzelli, Miriam; Parravano, Mariacristina; Franchi, Sara; Ng, Sueko M; Virgili, Gianni

    2016-01-01

    Background The diagnosis of glaucoma is traditionally based on the finding of optic nerve head (ONH) damage assessed subjectively by ophthalmoscopy or photography or by corresponding damage to the visual field assessed by automated perimetry, or both. Diagnostic assessments are usually required when ophthalmologists or primary eye care professionals find elevated intraocular pressure (IOP) or a suspect appearance of the ONH. Imaging tests such as confocal scanning laser ophthalmoscopy (HRT), optical coherence tomography (OCT) and scanning laser polarimetry (SLP, as used by the GDx instrument), provide an objective measure of the structural changes of retinal nerve fibre layer (RNFL) thickness and ONH parameters occurring in glaucoma. Objectives To determine the diagnostic accuracy of HRT, OCT and GDx for diagnosing manifest glaucoma by detecting ONH and RNFL damage. Search methods We searched several databases for this review. The most recent searches were on 19 February 2015. Selection criteria We included prospective and retrospective cohort studies and case-control studies that evaluated the accuracy of OCT, HRT or the GDx for diagnosing glaucoma. We excluded population-based screening studies, since we planned to consider studies on self-referred people or participants in whom a risk factor for glaucoma had already been identified in primary care, such as elevated IOP or a family history of glaucoma. We only considered recent commercial versions of the tests: spectral domain OCT, HRT III and GDx VCC or ECC. Data collection and analysis We adopted standard Cochrane methods. We fitted a hierarchical summary ROC (HSROC) model using the METADAS macro in SAS software. After studies were selected, we decided to use 2 × 2 data at 0.95 specificity or closer in meta-analyses, since this was the most commonly-reported level. Main results We included 106 studies in this review, which analysed 16,260 eyes (8353 cases, 7907 controls) in total. Forty studies (5574

  3. Motor nerves of the head and neck that are susceptible to damage during dermatological surgery.

    PubMed

    Brown, S M; Oliphant, T; Langtry, J

    2014-08-01

    As the incidence of non melanoma skin cancer rises, dermatologists will increasingly be called upon to perform excisions in the head and neck region. Damage to the motor nerves of the head and neck represents an important adverse event for patients, and a source of litigation for surgeons. Understanding the anatomy of this region is key to counselling patients about the possibility of motor nerve injury associated with particular skin surgical procedures. We describe the anatomy of the motor nerves of the head and neck that are most vulnerable to injury during dermatological surgery. The consequences of injury are outlined, and the surface anatomy and anatomical landmarks that may be used to identify the relevant danger zones are described.

  4. Digitizing stereoscopic optic nerve head photographs for storage and viewing using a personal computer.

    PubMed

    Nesher, Ronit; Zacharopoulos, Ioannis; Assia, Ehud I; Schuman, Joel S

    2005-01-01

    Careful examination and monitoring of optic nerve head changes is essential in the treatment of patients with glaucoma. This often results in accumulation of numerous photographs and required appropriate storage space. A simple, inexpensive, and efficient means of storing and viewing stereoscopic optic nerve head photographs is described. Images were acquired with a fundus camera, on a color slide film. Slides were then scanned and digitized. A handheld stereoscope was used for stereoscopic viewing on a computer monitor. A scanning resolution of 300 dpi appeared optimal. At this resolution, the storage utilization was 16 kilobytes and the scanning time was 160 seconds per patient.

  5. Short-term changes in the optic nerve head and visual field after trabeculectomy

    PubMed Central

    Figus, M; Lazzeri, S; Nardi, M; Bartolomei, M P; Ferreras, A; Fogagnolo, P

    2011-01-01

    Aims or Purpose To evaluate short-term changes in optic nerve head topography and visual field induced by surgical reduction of intraocular pressure. Methods A prospective study was performed on 56 eyes of 56 patients with uncontrolled primary open-angle glaucoma despite maximum medical therapy, which underwent trabeculectomy. Optic nerve head evaluations by means of Heidelberg Retina Tomograph, and visual field tests were performed pre-operatively, and at 3 and 6 months after surgery. Differences in intraocular pressure, visual field indices, and Heidelberg Retina Tomograph parameters were evaluated with the t-test for paired data. A linear regression model was calculated to analyze the relationship between intraocular pressure reduction and visual field changes, and optic nerve head changes. Results Mean intraocular pressure decreased from 24.4±5.0 mm Hg to 12.1±3.1 mm Hg (month 3, P<0.001), and 10.6±2.8 mm Hg (month 6, P<0.001) after trabeculectomy. Mean retinal nerve fiber layer thickness (baseline, 0.19±0.034; month 3, 0.24±0.039, P=0.05; month 6, 0.21±0.037, P=0.05) showed a statistical significant change compared with baseline values. Conclusions In this 6-months study, a significant increase in retinal nerve fiber layer thickness was detected after glaucoma filtration surgery. PMID:21617695

  6. Repeatability and reproducibility of optic nerve head perfusion measurements using optical coherence tomography angiography

    NASA Astrophysics Data System (ADS)

    Chen, Chieh-Li; Bojikian, Karine D.; Xin, Chen; Wen, Joanne C.; Gupta, Divakar; Zhang, Qinqin; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.; Wang, Ruikang K.

    2016-06-01

    Optical coherence tomography angiography (OCTA) has increasingly become a clinically useful technique in ophthalmic imaging. We evaluate the repeatability and reproducibility of blood perfusion in the optic nerve head (ONH) measured using optical microangiography (OMAG)-based OCTA. Ten eyes from 10 healthy volunteers are recruited and scanned three times with a 68-kHz Cirrus HD-OCT 5000-based OMAG prototype system (Carl Zeiss Meditec Inc., Dublin, California) centered at the ONH involving two separate visits within six weeks. Vascular images are generated with OMAG processing by detecting the differences in OCT signals between consecutive B-scans acquired at the same retina location. ONH perfusion is quantified as flux, vessel area density, and normalized flux within the ONH for the prelaminar, lamina cribrosa, and the full ONH. Coefficient of variation (CV) and intraclass correlation coefficient (ICC) are used to evaluate intravisit and intervisit repeatability, and interobserver reproducibility. ONH perfusion measurements show high repeatability [CV≤3.7% (intravisit) and ≤5.2% (intervisit)] and interobserver reproducibility (ICC≤0.966) in all three layers by three metrics. OCTA provides a noninvasive method to visualize and quantify ONH perfusion in human eyes with excellent repeatability and reproducibility, which may add additional insight into ONH perfusion in clinical practice.

  7. Natural motion of the optic nerve head revealed by high speed phase-sensitive OCT

    NASA Astrophysics Data System (ADS)

    OHara, Keith; Schmoll, Tilman; Vass, Clemens; Leitgeb, Rainer A.

    2013-03-01

    We use phase-sensitive optical coherence tomography (OCT) to measure the deformation of the optic nerve head during the pulse cycle, motivated by the possibility that these deformations might be indicative of the progression of glaucoma. A spectral-domain OCT system acquired 100k A-scans per second, with measurements from a pulse-oximeter recorded simultaneously, correlating OCT data to the subject's pulse. Data acquisition lasted for 2 seconds, to cover at least two pulse cycles. A frame-rate of 200-400 B-scans per second results in a sufficient degree of correlated speckle between successive frames that the phase-differences between fames can be extracted. Bulk motion of the entire eye changes the phase by several full cycles between frames, but this does not severely hinder extracting the smaller phase-changes due to differential motion within a frame. The central cup moves about 5 μm/s relative to the retinal-pigment-epithelium edge, with tissue adjacent to blood vessels showing larger motion.

  8. Unilateral compression neuropathy of the hypoglossal nerve due to head suspension orthosis in mitochondriopathy.

    PubMed

    Finsterer, Josef; Hess, Barbara

    2004-12-01

    An 85-year-old woman with multisystem mitochondriopathy experienced tension headache, cervical pain, torque head-posture, and vertigo since 1980 for which she was continuously wearing a head-suspension-orthosis- since 1990. Since 1996 she developed severe left-sided weakness and wasting of the tongue. Needle-EMG of the left genioglossus muscle revealed abnormal spontaneous activity and reduced interference-pattern. No morphological alterations in the anatomical course of the hypoglossal nerve were found. Severe, unilateral weakness and wasting of the tongue was interpreted due to chronic compression of the hypoglossal nerve by long-standing use of a head-suspension-orthosis for cervical pain from cervical muscle weakness and resulting spinal degeneration.

  9. The course of axons through the retina and optic nerve head.

    PubMed

    Radius, R L; Anderson, D R

    1979-06-01

    By identifying degenerating axons in tissue specimens from 22 primate eyes, it was possible to demonstrate the normal course of axon fibers. Nerve fiber bundles from a group of retinal ganglion cells travel together with little tendency to disperse laterally. In addition, axons are stratified such that processes from more central ganglion cells are successfully added to the inner strata of the retinal nerve fiber layer. Within and behind the lamina cribrosa, areas of degeneration following retinal photocoagulation were well circumscribed and confined to a group of adjacent axon bundles. This degree of retinotopic organization of axons within the nerve head and retinal fiber layer is believed to be consistent with the premise that isolated lesions within the lamina cribrosa could cause well-organized paracentral scotomas such as those characteristic of early glaucoma.

  10. Isolation of intact astrocytes from the optic nerve head of adult mice.

    PubMed

    Choi, Hee Joo; Sun, Daniel; Jakobs, Tatjana C

    2015-08-01

    The astrocytes of the optic nerve head are a specialized subtype of white matter astrocytes that form the direct cellular environment of the unmyelinated ganglion cell axons. Due to their potential involvement in glaucoma, these astrocytes have become a target of research. Due to the heterogeneity of the optic nerve tissue, which also contains other cell types, in some cases it may be desirable to conduct gene expression studies on small numbers of well-characterized astrocytes or even individual cells. Here, we describe a simple method to isolate individual astrocytes. This method permits obtaining astrocytes with intact morphology from the adult mouse optic nerve and reduces contamination of the isolated astrocytes by other cell types. Individual astrocytes can be recognized by their morphology and collected under microscopic control. The whole procedure can be completed in 2-3 h. We also discuss downstream applications like multiplex single-cell PCR and quantitative PCR (qPCR).

  11. Isolated Oculomotor Nerve Palsy Following Minor Head Trauma; a Case report

    PubMed Central

    GoliKhatir, Iraj; Aminiahidashti, Hamed; Motamed Motlagh, Hasan; Heidari, Seyed Farshad

    2017-01-01

    Isolated third nerve palsy develops in numerous intracranial pathologies such as closed head trauma, tumor, and aneurysm. This report describes a 61 years old female with an abrasion on the left forehead and ptosis of the left eye. Initial computed tomography did not reveal any causative cerebral and vascular lesions or orbital and cranial fractures. High-resolution and multi-axial enhanced Magnetic resonance imaging (MRI) can be helpful in diagnosis and monitoring of patients with this rare phenomenon. PMID:28286849

  12. Optical nerve identification in head and neck surgery after Er:YAG laser ablation.

    PubMed

    Stelzle, Florian; Knipfer, Christian; Bergauer, Bastian; Rohde, Maximilian; Adler, Werner; Tangermann-Gerk, Katja; Nkenke, Emeka; Schmidt, Michael

    2014-09-01

    Facial nerve function may be hampered by iatrogenic damage during head and neck laser surgery procedures. Optical techniques can serve as a basis for feedback-controlled tissue-specific laser surgery on the jaw bone and the parotid gland. In order to preserve nerve tissue during laser surgery, the alteration of optical tissue properties through laser-tissue interactions have to be taken into account. It was the aim of this study to evaluate the viability of optical tissue differentiation through diffuse reflectance spectroscopy after exposure to laser light as a basis for a feedback system for tissue-specific laser surgery. Spectra of diffuse reflectance (wavelength, 350-650 nm) of nerves, salivary glands, and cortical and cancellous bone of the midfacial region (ex vivo domestic pig heads) were acquired before/after Er:YAG laser (wavelength, 2.94 μm) ablation (each 16,800 spectra). Principal component analysis was computed followed by quadratic discriminant analysis. The tissue classification performance as well as area under the curve (AUC) sensitivity and specificity for tissue differentiation was assessed before and after laser-tissue exposure. A high classification performance was observed before laser ablation (total error, 7.74%). Nerve tissue was differentiated from bone and salivary glands with results greater than 0.96 in AUC, sensitivity and specificity. After laser exposure, a total classification error of 18.61% was observed. The differentiation of nerve tissue was reduced with an AUC of >0.94, sensitivity of >0.95, and specificity >0.87. Er:YAG laser ablation only slightly reduces the differentiation performance through diffuse reflectance in the investigated tissue types. The results show the general viability of diffuse reflectance spectroscopy in identifying neural structures in the vicinity of salivary glands and bone as a basis for nerve preservation during feedback-controlled laser surgery.

  13. Effect of head tilt on repeatability of optic nerve head parameters using cirrus spectral-domain optical coherence tomography

    PubMed Central

    Koh, Lilian Hui Li; Ismail, Muhammad Amir; Yap, Sae Cheong; Wong, Elizabeth Poh Ying; Yip, Leonard Wei Leon

    2016-01-01

    AIM To assess the repeatability of measuring optic nerve head (ONH) parameters using the Cirrus optical coherence tomography (OCT), as well as to assess the effect of head tilt on these measurements. METHODS Thirty healthy participants with no evidence of glaucoma were recruited for the study. Visual acuity, intraocular pressure, standard automated perimetry and ocular examination were performed for each participant. One eye was then randomly selected and scanned undilated with the Cirrus OCT in 3 positions (neutral, 30° right tilt and 30° left tilt). RESULTS Data collected from 29 eyes were used for analysis. One patient was omitted due to poor scan quality. The repeatability of the ONH parameters was analyzed using analysis of variance, coefficient of variation (COV) and intraclass correlation coefficient (ICC). Analysis of variance showed no statistically significant difference between 3 scans in a single position. There was good agreement between measurements (ICC 0.919-0.996, COV 1.94%-5.48%). Even with the presence of head tilt, repeated scans in the 3 positions showed good agreement as well (ICC 0.888-0.996, COV 2.04%-5.39%). CONCLUSION Serial measurements of ONH parameters using the Cirrus OCT are found to have good repeatability. The ONH parameters with Cirrus OCT also maintain good repeatability despite head tilt. PMID:27585788

  14. The morphology and spatial arrangement of astrocytes in the optic nerve head of the mouse.

    PubMed

    Sun, Daniel; Lye-Barthel, Ming; Masland, Richard H; Jakobs, Tatjana C

    2009-09-01

    We evaluated the shapes, numbers, and spatial distribution of astrocytes within the glial lamina, an astrocyte-rich region at the junction of the retina and optic nerve. A primary aim was to determine how the population of astrocytes, collectively, partitions the axonal space in this region. Astrocyte processes labeled with glial fibrillary acidic protein (GFAP) compartmentalize ganglion cell axons into bundles, forming "glial tubes," and giving the glial architecture of the optic nerve head in transverse section a honeycomb appearance. The shapes of individual astrocytes were studied by using transgenic mice that express enhanced green fluorescent protein in isolated astrocytes (hGFAPpr-EGFP). Within the glial lamina the astrocytes were transverse in orientation, with thick, smooth primary processes emanating from a cytoplasmic expansion of the soma. Spaces between the processes of neighboring astrocytes were spatially aligned, to form the apertures through which the bundles of optic axons pass. The processes of individual astrocytes were far-reaching-they could span most of the width of the nerve-and overlapped the anatomical domains of other near and distant astrocytes. Thus, astrocytes in the glial lamina do not tile: each astrocyte participates in ensheathing approximately one-quarter of all of the axon bundles in the nerve, and each glial tube contains the processes of about nine astrocytes. This raises the mechanistic question of how, in glaucoma or other cases of nerve damage, the glial response can be confined to a circumscribed region where damage to axons has occurred.

  15. Effect of the consumption of ethanol on the microcirculation of the human optic nerve head in the acute phase

    PubMed

    Kojima; Sugiyama; Kojima; Azuma; Ito

    2000-05-01

    Purpose: The effect of the consumption of ethanol on the circulation of the optic nerve head (ONH) in the human eye in the acute phase and its mechanism were studied.Methods: Eleven volunteers drank a bottle of beer (633 mL) with or without ethanol (29.5 g). Normalized blur (NB), a quantitative index of blood flow velocity, was measured in the temporal site of the ONH. NB, blood pressure (BP) and pulse rate (PR) were measured before, immediately after, and every 15 minutes for 90 minutes after consumption. Intraocular pressure (IOP) and plasma ethanol concentration were measured before, and 30 and 90 minutes after consumption. Genotyping of the aldehyde dehydrogenase (ALDH) 2 gene was also performed.Results: NB in the ONH increased significantly from 15 to 45 minutes after consumption of ethanol and the maximum increase was 14% at 15 minutes. IOP was lowered at 90 minutes after consumption, but it was not significant. Mean BP was lowered significantly after 60 minutes. PR and ocular perfusion pressure did not change. A significant correlation was found between plasma ethanol concentration at 30 minutes and maximum NB. NB in the ALDH 2-deficient group was significantly larger from 15 to 45 minutes after consumption than in the proficient group.Conclusions: It appeared that the consumption of ethanol can increase the blood flow in the human ONH in the acute phase through decreased resistance in blood vessels induced by acetaldehyde, a metabolite of ethanol.

  16. Radiation-induced lower cranial nerve palsy in patients with head and neck carcinoma

    PubMed Central

    JANSSEN, STEFAN; GLANZMANN, CHRISTOPH; YOUSEFI, BITA; LOEWENICH, KARL; HUBER, GERHARD; SCHMID, STEPHAN; STUDER, GABRIELA

    2015-01-01

    Radiation-induced cranial nerve palsy (RICNP) is a severe long-term complication in patients with head and neck cancer following high-dose radiation therapy (RT). We present the case report of a patient with bilateral RICNP of the hypoglossal and vagus cranial nerves (XII/X) following postoperative RT in the era prior to the introduction of intensity-modulated RT (IMRT), and an analysis of our IMRT patient cohort at risk including the case of a XII RICNP. A total of 201 patients whose glosso-pharyngeal (IX), X and XII cranial nerves had been exposed to >65 Gy definitive IMRT in our institution between January, 2002 and December, 2012 with or without systemic therapy, were retrospectively identified. A total of 151 patients out of 201 fulfilling the following criteria were included in the analysis: Locoregionally controlled disease, with a follow-up (FU) of >24 months and >65 Gy exposure of the nerves of interest. So far, one of the assessed 151 IMRT patients at risk exhibited symptoms of RICNP after 6 years. The mean/median FU of the entire cohort was 71/68 months (range, 27–145). The results were compared with literature reports. In conclusion, RICNP appears to be a rare complication. However, a longer FU and a larger sample size are required to draw reliable conclusions on the incidence of RICNP in the era of IMRT. PMID:26171186

  17. Aminoguanidine effects on nerve blood flow, vascular permeability, electrophysiology, and oxygen free radicals

    SciTech Connect

    Kihara, Mikihiro; Schmelzer, J.D.; Poduslo, J.F.; Curran, G.L.; Nickander, K.K.; Low, P.A. )

    1991-07-15

    Since advanced glycosylation end products have been suggested to mediate hyperglycemia-induced microvascular atherogenesis and because aminoguanidine (AG) prevents their generation, the authors examined whether AG could prevent or ameliorate the physiologic and biochemical indices of streptozotocin (STZ)-induced experimental diabetic neuropathy. Four groups of adult Sprague-Dawley rats were studied: group I received STZ plus AG, group II received STZ plus AG, group III received STZ alone, and group IV was a control. They monitored conduction and action potential amplitudes serially in sciatic-tibial and caudal nerves, nerve blood flow, oxygen free radical activity (conjugated dienes and hydroperoxides), and the product of the permeability coefficient and surface area to {sup 125}I-labeled albumin. STZ-induced diabetes (group III) caused a 57% reduction in nerve blood flow and in abnormal nerve conduction and amplitudes and a 60% increase in conjugated dienes. Nerve blood flow was normalized by 8 weeks with AG (groups I and II) and conduction was significantly improved, in a dose-dependent manner, by 16 and 24 weeks in sciatic-tibial and caudal nerves, respectively. The permeability coefficient was not impaired, suggesting a normal blood-nerve barrier function for albumin, and the oxygen free-radical indices were not ameliorated by AG. They suggest that AG reverses nerve ischemia and more gradually improves their electrophysiology by an action on nerve microvessels. AG may have potential in the treatment of diabetic neuropathy.

  18. Effects of Head-down Tilt on Nerve Conduction in Rhesus Monkeys

    PubMed Central

    Sun, Bo; Zhang, Xiao-Yun; Liu, Li-Zhi; Chen, Zhao-Hui; Dai, Zhong-Quan; Huang, Xu-Sheng

    2017-01-01

    Background: Few studies have focused on peripheral nerve conduction during exposure to microgravity. The −6° head-down tilt (HDT) comprises an experimental model used to simulate the space flight environment. This study investigated nerve conduction characteristics of rhesus monkeys before and after prolonged exposure to HDT. Methods: Six rhesus monkeys (3–4 years old) were tilted backward 6° from the horizontal. Nerve conduction studies (NCSs) were performed on the median, ulnar, tibial, and fibular motor nerves. Analysis of variance with a randomized block design was conducted to compare the differences in the NCS before and 7, 21, and 42 days after the −6° HDT. Results: The proximal amplitude of the CMAP of the median nerve was significantly decreased at 21 and 42 days of HDT compared with the amplitude before HDT (4.38 ± 2.83 vs. 8.40 ± 2.66 mV, F = 4.85, P = 0.013 and 3.30 ± 2.70 vs. 8.40 ± 2.66 mV, F = 5.93, P = 0.004, respectively). The distal amplitude of the CMAP of the median nerve was significantly decreased at 7, 21, and 42 days of HDT compared with the amplitude before HDT (7.28 ± 1.27 vs. 10.25 ± 3.40 mV, F = 4.03, P = 0.039; 5.05 ± 2.01 vs. 10.25 ± 3.40 mV, F = 6.25, P = 0.04; and 3.95 ± 2.79 vs. 10.25 ± 3.40 mV, F = 7.35, P = 0.01; respectively). The proximal amplitude of the CMAP of the tibial nerve was significantly decreased at 42 days of HDT compared with the amplitude before HDT (6.14 ± 1.94 vs. 11.87 ± 3.19 mV, F = 5.02, P = 0.039). Conclusions: This study demonstrates that the compound muscle action potential amplitudes of nerves are decreased under simulated microgravity in rhesus monkeys. Moreover, rhesus monkeys exposed to HDT might be served as an experimental model for the study of NCS under microgravity. PMID:28139516

  19. Detection of Glaucoma Progression with Stratus OCT Retinal Nerve Fiber Layer, Optic Nerve Head, and Macular Thickness Measurements

    PubMed Central

    Medeiros, Felipe A.; Zangwill, Linda M.; Alencar, Luciana M.; Bowd, Christopher; Sample, Pamela A.; Susanna, Remo; Weinreb, Robert N.

    2010-01-01

    Purpose To evaluate and compare the ability of optical coherence tomography (OCT) retinal nerve fiber layer (RNFL), optic nerve head, and macular thickness parameters to detect progressive structural damage in glaucoma. Methods This observational cohort study included 253 eyes of 253 patients. Images were obtained annually with the Stratus OCT (Carl Zeiss Meditec, Inc., Dublin, CA) along with optic disc stereophotographs and standard automated perimetry (SAP) visual fields. The median follow-up time was 4.01 years. Progression was determined by the Guided Progression Analysis software for SAP (Carl Zeiss Meditec, Inc.) and by masked assessment of optic disc stereophotographs performed by expert graders. Random coefficient models and receiver operating characteristic (ROC) curves were used to evaluate the relationship between change in Stratus OCT parameters over time and progression as determined by SAP and/or stereophotographs. Results From the 253 eyes, 31 (13%) showed progression over time by stereophotographs and/or SAP. Mean rates of change in average RNFL thickness were significantly higher for progressors compared with nonprogressors (−0.72 μm/y vs. 0.14 μm/y; P = 0.004), with sensitivity of 77% for specificity of 80%. RNFL parameters performed significantly better than ONH and macular thickness measurements in discriminating progressors from nonprogressors. The parameters with the largest ROC curve areas for each scanning area were inferior RNFL thickness (0.84), cup area (0.66), and inferior inner macula thickness (0.64). Conclusions Stratus OCT RNFL parameters discriminated between eyes progressing by visual fields or optic disc photographs and eyes that remained stable by these methods and performed significantly better than ONH and macular thickness parameters in detecting change over time. PMID:19815731

  20. Detection of blood-nerve barrier permeability by magnetic resonance imaging.

    PubMed

    Wessig, Carsten

    2011-01-01

    The blood-nerve barrier (BNB) separates the endoneurium from the endovascular space and the epineurial connective tissue. An intact BNB is very important for integrity and functions of the nerve fibers within the endoneurial space. Disruption of the BNB which leads to functional and structural impairment of the peripheral nerve plays an important role in many disorders of the peripheral nerve like Wallerian degeneration, inflammatory nerve disorders, and demyelination. So far, this increased BNB permeability can only be assessed ex vivo. Assessing BNB disruption in vivo would be of great value for studying disorders of the peripheral nervous system. Gadofluorine M (Gf), a new amphiphilic contrast agent for MRI, accumulates in rat nerves with increased permeability of the BNB. After application of Gf, T1-weighted MR images show contrast enhancement of nerves with a disrupted BNB. This new tool of assessing BNB permeability in vivo is described.

  1. Elevated hydrostatic pressure activates sodium/hydrogen exchanger-1 in rat optic nerve head astrocytes.

    PubMed

    Mandal, Amritlal; Shahidullah, Mohammad; Delamere, Nicholas A; Terán, Marcos A

    2009-07-01

    Optic nerve head astrocytes become abnormal in eyes that have elevated intraocular pressure, and cultured astrocytes display altered protein expression after being subjected for > or = 1 days to elevated hydrostatic pressure. Here we show that 2-h elevated hydrostatic pressure (15 or 30 mmHg) causes phosphorylation of ERK1/2, ribosomal S6 protein kinase (p90(RSK)), and Na/H exchanger (NHE)1 in cultured rat optic nerve head astrocytes as judged by Western blot analysis. The MEK/ERK inhibitor U0126 abolished phosphorylation of NHE1 and p90(RSK) as well as ERK1/2. To examine NHE1 activity, cytoplasmic pH (pH(i)) was measured with BCECF and, in some experiments, cells were acidified by 5-min exposure to 20 mM ammonium chloride. Although baseline pH(i) was unaltered, the rate of pH(i) recovery from acidification was fourfold higher in pressure-treated astrocytes. In the presence of either U0126 or dimethylamiloride (DMA), an NHE inhibitor, hydrostatic pressure did not change the rate of pH(i) recovery. The findings are consistent with NHE1 activation due to phosphorylation of ERK1/2, p90(RSK), and NHE1 that occurs in response to hydrostatic pressure. These responses may precede long-term changes of protein expression known to occur in pressure-stressed astrocytes.

  2. Differentiating Mild Papilledema and Buried Optic Nerve Head Drusen Using Spectral Domain Optical Coherence Tomography

    PubMed Central

    Kulkarni, Kaushal M.; Pasol, Joshua; Rosa, Potyra R.; Lam, Byron L.

    2013-01-01

    Purpose To evaluate the clinical utility of spectral domain optical coherence tomography (SD-OCT) in differentiating mild papilledema from buried optic nerve head drusen (ONHD). Design Comparative case series. Participants 16 eyes of 9 patients with ultrasound-proven buried ONHD, 12 eyes of 6 patients with less than or equal to Frisén grade 2 papilledema due to idiopathic intracranial hypertension. 2 normal fellow eyes of patients with buried ONHD were included. Methods A raster scan on the optic nerve and retinal nerve fiber layer (RNFL) thickness analysis was performed on each eye using SD-OCT. Eight eyes underwent enhanced depth imaging SD-OCT. Images were assessed qualitatively and quantitatively to identify differentiating features between buried ONHD and papilledema. Five clinicians trained with a tutorial and masked to the underlying diagnosis reviewed the SD-OCT images of each eye independently to determine the diagnosis. Main outcome measures Differences in RNFL thickness in each quadrant between the two groups, and diagnostic accuracy of five independent clinicians based on the SD-OCT images alone. Results We found no statistically significant difference in RNFL thickness between buried ONHD and papilledema in any of the four quadrants. Diagnostic accuracy among the readers was low and ranged from 50–64%. The kappa coefficient of agreement among the readers was 0.35 (95% Confidence interval: 0.19, 0.54). Conclusions SD-OCT is not clinically reliable in differentiating buried ONHD and mild papilledema. PMID:24321144

  3. Sequential-digital image correlation for mapping human posterior sclera and optic nerve head deformation.

    PubMed

    Pyne, Jeffrey D; Genovese, Katia; Casaletto, Luciana; Vande Geest, Jonathan P

    2014-02-01

    Optic nerve head (ONH) deformations may be involved in the onset or further development of glaucoma, including in patients with relatively normal intraocular pressures (IOPs). Characterizing posterior scleral deformations over physiological pressures may provide a better understanding of how changes in IOP lead to changes in the mechanical environment of the ONH and possibly retinal ganglion cell death. Pressure inflation measurement test protocols are commonly used to measure deformation of the peripapillary sclera with full-field noncontact optical methods. The purpose of this work was to develop and validate a new sequential 3D digital image correlation (S-DIC) approach for quantification of posterior scleral pressure induced deformation that improves z (in-depth) resolution of the DIC measurement without losing in-plane sensitivity, while also being able to contour and map deformations of the complex-shaped ONH. Our approach combines two orthogonal axes of parallax with standard 3D DIC methods using a single high-resolution camera. The enhanced capabilities of S-DIC with respect to standard 3D DIC has been demonstrated by carrying out a complete benchmark for shape, deformation, and strain measurement on an object of known complex geometry. Our S-DIC method provided a reconstruction accuracy of 0.17% and an uncertainty in z-position measurement of 8 μm. The developed methodology has also been applied to a human posterior scleral shell, including the full peripapillary sclera and optic nerve. The relatively inexpensive S-DIC approach may provide new information on the biomechanical deformations of the optic nerve head and, thus, the death of retinal ganglion cells in primary open angle glaucoma.

  4. Evaluation of Multiple Blood Matrices for Assessment of Human Exposure to Nerve Agents.

    PubMed

    Schulze, Nicholas D; Hamelin, Elizabeth I; Winkeljohn, W Rucks; Shaner, Rebecca L; Basden, Brian J; deCastro, B Rey; Pantazides, Brooke G; Thomas, Jerry D; Johnson, Rudolph C

    2016-04-01

    Biomedical samples may be used to determine human exposure to nerve agents through the analysis of specific biomarkers. Samples received may include serum, plasma, whole blood, lysed blood and, due to the toxicity of these compounds, postmortem blood. To quantitate metabolites resulting from exposure to sarin (GB), soman (GD), cyclosarin (GF), VX and VR, these blood matrices were evaluated individually for precision, accuracy, sensitivity and specificity. Accuracies for these metabolites ranged from 100 to 113% with coefficients of variation ranging from 2.31 to 13.5% across a reportable range of 1-100 ng/mL meeting FDA recommended guidelines for bioanalytical methods in all five matrices. Limits of detection were calculated to be 0.09-0.043 ng/mL, and no interferences were detected in unexposed matrix samples. The use of serum calibrators was also determined to be a suitable alternative to matrix-matched calibrators. Finally, to provide a comparative value between whole blood and plasma, the ratio of the five nerve agent metabolites measured in whole blood versus plasma was determined. Analysis of individual whole blood samples (n = 40), fortified with nerve agent metabolites across the reportable range, resulted in average nerve agent metabolite blood to plasma ratios ranging from 0.53 to 0.56. This study demonstrates the accurate and precise quantitation of nerve agent metabolites in serum, plasma, whole blood, lysed blood and postmortem blood. It also provides a comparative value between whole blood and plasma samples, which can assist epidemiologists and physicians with interpretation of test results from blood specimens obtained under variable conditions.

  5. Evaluation of Multiple Blood Matrices for Assessment of Human Exposure to Nerve Agents

    PubMed Central

    Schulze, Nicholas D.; Hamelin, Elizabeth I.; Winkeljohn, W. Rucks; Shaner, Rebecca L.; Basden, Brian J.; deCastro, B. Rey; Pantazides, Brooke G.; Thomas, Jerry D.; Johnson, Rudolph C.

    2016-01-01

    Biomedical samples may be used to determine human exposure to nerve agents through the analysis of specific biomarkers. Samples received may include serum, plasma, whole blood, lysed blood and, due to the toxicity of these compounds, postmortem blood. To quantitate metabolites resulting from exposure to sarin (GB), soman (GD), cyclosarin (GF), VX and VR, these blood matrices were evaluated individually for precision, accuracy, sensitivity and specificity. Accuracies for these metabolites ranged from 100 to 113% with coefficients of variation ranging from 2.31 to 13.5% across a reportable range of 1–100 ng/mL meeting FDA recommended guidelines for bioanalytical methods in all five matrices. Limits of detection were calculated to be 0.09–0.043 ng/mL, and no interferences were detected in unexposed matrix samples. The use of serum calibrators was also determined to be a suitable alternative to matrix-matched calibrators. Finally, to provide a comparative value between whole blood and plasma, the ratio of the five nerve agent metabolites measured in whole blood versus plasma was determined. Analysis of individual whole blood samples (n = 40), fortified with nerve agent metabolites across the reportable range, resulted in average nerve agent metabolite blood to plasma ratios ranging from 0.53 to 0.56. This study demonstrates the accurate and precise quantitation of nerve agent metabolites in serum, plasma, whole blood, lysed blood and postmortem blood. It also provides a comparative value between whole blood and plasma samples, which can assist epidemiologists and physicians with interpretation of test results from blood specimens obtained under variable conditions. PMID:26861671

  6. Effects of Wrist Posture and Fingertip Force on Median Nerve Blood Flow Velocity

    PubMed Central

    Wilson, Katherine E.; Tat, Jimmy

    2017-01-01

    Purpose. The purpose of this study was to assess nerve hypervascularization using high resolution ultrasonography to determine the effects of wrist posture and fingertip force on median nerve blood flow at the wrist in healthy participants and those experiencing carpal tunnel syndrome (CTS) symptoms. Methods. The median nerves of nine healthy participants and nine participants experiencing symptoms of CTS were evaluated using optimized ultrasonography in five wrist postures with and without a middle digit fingertip press (0, 6 N). Results. Both wrist posture and fingertip force had significant main effects on mean peak blood flow velocity. Blood flow velocity with a neutral wrist (2.87 cm/s) was significantly lower than flexed 30° (3.37 cm/s), flexed 15° (3.27 cm/s), and extended 30° (3.29 cm/s). Similarly, median nerve blood flow velocity was lower without force (2.81 cm/s) than with force (3.56 cm/s). A significant difference was not found between groups. Discussion. Vascular changes associated with CTS may be acutely induced by nonneutral wrist postures and fingertip force. This study represents an early evaluation of intraneural blood flow as a measure of nerve hypervascularization in response to occupational risk factors and advances our understanding of the vascular phenomena associated with peripheral nerve compression. PMID:28286771

  7. Automatic segmentation of the optic nerve head for deformation measurements in video rate optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Hidalgo-Aguirre, Maribel; Gitelman, Julian; Lesk, Mark Richard; Costantino, Santiago

    2015-11-01

    Optical coherence tomography (OCT) imaging has become a standard diagnostic tool in ophthalmology, providing essential information associated with various eye diseases. In order to investigate the dynamics of the ocular fundus, we present a simple and accurate automated algorithm to segment the inner limiting membrane in video-rate optic nerve head spectral domain (SD) OCT images. The method is based on morphological operations including a two-step contrast enhancement technique, proving to be very robust when dealing with low signal-to-noise ratio images and pathological eyes. An analysis algorithm was also developed to measure neuroretinal tissue deformation from the segmented retinal profiles. The performance of the algorithm is demonstrated, and deformation results are presented for healthy and glaucomatous eyes.

  8. Bilateral optic nerve head drusen with chorioretinal coloboma in the right eye.

    PubMed

    Dehghani, Ali Reza; Rezaei, Leila; Ghanbari, Heshmatollah

    2016-01-01

    Chorioretinal coloboma is a congenital defect of the eye caused by improper closure of the embryonic fissure. Optic nerve head drusen (ONHD) are white calcareous deposits that are generally asymptomatic. We report a very rare association of both in a healthy patient with no any systemic syndrome. A 16-year-old man was referred to our clinic from suffering blurred vision. Best corrected visual acuity of the right eye was 6/10 and 10/10 in the left one. External ocular and slit lamp examination were normal. Dilated ophthalmoscopy showed marked swelling in both optic nerves and chorioretinal coloboma in the right eye inferiorly. Ultrasonography showed an echodense structure with acoustic shadowing in both eyes consistent with buried ONHD. Visual field testing showed normal field in the left eye and moderate superior field depression in the right eye corresponding to inferior coloboma in funduscopy. Results of general medical and neurologic, cardiologic, and other examinations were normal. To the best our knowledge combination of bilateral ONHD and unilateral chorioretinal coloboma in a healthy patient with no any systemic syndrome has not been published in the literature. We reported this very rare association and recommended examine eyes and other body organs. In such cases that coloboma is associated with ONHD, we should keep in mind Noonan syndrome. The diagnosis of Noonan syndrome is clinical and confirm by the consultant pediatricians and clinical geneticists.

  9. The role of astrocytes in optic nerve head fibrosis in glaucoma.

    PubMed

    Schneider, Magdalena; Fuchshofer, Rudolf

    2016-01-01

    Glaucoma is defined as a progressive optic neuropathy and is characterized by an irreversible loss of retinal ganglion cells. The main risk factor to develop glaucoma is an increased intraocular pressure (IOP). During the course of glaucoma structural changes in the optic nerve head (ONH) take place which lead to the characteristic excavation or cupping of the ONH. In this review we will focus on mechanisms and processes involved in structural alterations of the extracellular matrix in the lamina cribrosa (LC) of the ONH, which are associated with astrocytes. In glaucoma, a disordered deposition of elastic and collagen fibers and a typical pronounced thickening of the connective tissue septae surrounding the nerve fibers can be observed in the LC region. The remodeling process of the LC and the loss of ON axons are associated with a conversion of astrocytes from quiescent to a reactivated state. The extracellular matrix changes in the LC are thought to be due to a disturbed homeostatic balance of growth factors and the reactivated astrocytes are part of this process. Reactivated astrocytes, remodeling of the ECM within the LC and an elevated IOP are taking part in the retinal ganglion cell loss in glaucoma.

  10. The Impact of Ocular Pressures, Material Properties and Geometry on Optic Nerve Head Deformation

    NASA Technical Reports Server (NTRS)

    Feola, Andrew J.; Myers, Jerry G.; Raykin, Julia; Nelson, Emily S.; Samuels, Brian C.; Ethier C. Ross

    2017-01-01

    Alteration in intracranial pressure (ICP) has been associated with various diseases that cause visual impairment, including glaucoma, idiopathic intracranial hypertension and Visual Impairment and Intracranial Pressure (VIIP) syndrome. However, how changes in ICP lead to vision loss is unclear, although it is hypothesized to involve deformations of the tissues in the optic nerve head (ONH). Recently, understanding the effect of ICP alterations on ocular tissues has become a major concern for NASA, where 42 of astronauts that partake in long duration space missions suffer from VIIP syndrome. Astronauts with VIIP syndrome suffer from visual impairment and changes in ocular anatomy that persist after returning to earth (1). It is hypothesized that the cephalad fluid shift that occurs upon entering microgravity increases ICP, which leads to an altered biomechanical environment in the posterior globe and optic nerve sheath, and subsequently VIIP syndrome. Our goal was to develop a finite element (FE) model to simulate the acute effects of elevated ICP on the posterior eye. Here, we simulated how inter-individual differences affect the deformation of ONH tissues. Further, we examined how several different geometries influenced deformations when exposed to elevated ICP.

  11. Bilateral optic nerve head drusen with chorioretinal coloboma in the right eye

    PubMed Central

    Dehghani, Ali Reza; Rezaei, Leila; Ghanbari, Heshmatollah

    2016-01-01

    Chorioretinal coloboma is a congenital defect of the eye caused by improper closure of the embryonic fissure. Optic nerve head drusen (ONHD) are white calcareous deposits that are generally asymptomatic. We report a very rare association of both in a healthy patient with no any systemic syndrome. A 16-year-old man was referred to our clinic from suffering blurred vision. Best corrected visual acuity of the right eye was 6/10 and 10/10 in the left one. External ocular and slit lamp examination were normal. Dilated ophthalmoscopy showed marked swelling in both optic nerves and chorioretinal coloboma in the right eye inferiorly. Ultrasonography showed an echodense structure with acoustic shadowing in both eyes consistent with buried ONHD. Visual field testing showed normal field in the left eye and moderate superior field depression in the right eye corresponding to inferior coloboma in funduscopy. Results of general medical and neurologic, cardiologic, and other examinations were normal. To the best our knowledge combination of bilateral ONHD and unilateral chorioretinal coloboma in a healthy patient with no any systemic syndrome has not been published in the literature. We reported this very rare association and recommended examine eyes and other body organs. In such cases that coloboma is associated with ONHD, we should keep in mind Noonan syndrome. The diagnosis of Noonan syndrome is clinical and confirm by the consultant pediatricians and clinical geneticists. PMID:27099847

  12. Assessment of Optic Nerve Head Drusen Using Enhanced Depth Imaging and Swept Source Optical Coherence Tomography

    PubMed Central

    Silverman, Anna L.; Tatham, Andrew J.; Medeiros, Felipe A.; Weinreb, Robert N.

    2015-01-01

    Background Optic nerve head drusen (ONHD) are calcific deposits buried or at the surface of the optic disc. Although ONHD may be associated with progressive visual field defects, the mechanism of drusen-related field loss is poorly understood. Methods for detecting and imaging disc drusen include B-scan ultrasonography, fundus autofluorescence, and optical coherence tomography (OCT). These modalities are useful for drusen detection but are limited by low resolution or poor penetration of deep structures. This review was designed to assess the potential role of new OCT technologies in imaging ONHD. Evidence Acquisition Critical appraisal of published literature and comparison of new imaging devices to established technology. Results The new imaging modalities of enhanced depth imaging optical coherence tomography (EDI-OCT) and swept source optical coherence tomography (SS-OCT) are able to provide unprecedented in vivo detail of ONHD. Using these devices it is now possible to quantify optic disc drusen dimensions and assess integrity of neighboring retinal structures, including the retinal nerve fiber layer. Conclusions EDI-OCT and SS-OCT have the potential to allow better detection of longitudinal changes in drusen and neural retina and improve our understanding of drusen-related visual field loss. PMID:24662838

  13. Estimating a structural bottle neck for eye-brain transfer of visual information from 3D-volumes of the optic nerve head from a commercial OCT device

    NASA Astrophysics Data System (ADS)

    Malmberg, Filip; Sandberg-Melin, Camilla; Söderberg, Per G.

    2016-03-01

    The aim of this project was to investigate the possibility of using OCT optic nerve head 3D information captured with a Topcon OCT 2000 device for detection of the shortest distance between the inner limit of the retina and the central limit of the pigment epithelium around the circumference of the optic nerve head. The shortest distance between these boundaries reflects the nerve fiber layer thickness and measurement of this distance is interesting for follow-up of glaucoma.

  14. Macrophage-Induced Blood Vessels Guide Schwann Cell-Mediated Regeneration of Peripheral Nerves.

    PubMed

    Cattin, Anne-Laure; Burden, Jemima J; Van Emmenis, Lucie; Mackenzie, Francesca E; Hoving, Julian J A; Garcia Calavia, Noelia; Guo, Yanping; McLaughlin, Maeve; Rosenberg, Laura H; Quereda, Victor; Jamecna, Denisa; Napoli, Ilaria; Parrinello, Simona; Enver, Tariq; Ruhrberg, Christiana; Lloyd, Alison C

    2015-08-27

    The peripheral nervous system has remarkable regenerative capacities in that it can repair a fully cut nerve. This requires Schwann cells to migrate collectively to guide regrowing axons across a 'bridge' of new tissue, which forms to reconnect a severed nerve. Here we show that blood vessels direct the migrating cords of Schwann cells. This multicellular process is initiated by hypoxia, selectively sensed by macrophages within the bridge, which via VEGF-A secretion induce a polarized vasculature that relieves the hypoxia. Schwann cells then use the blood vessels as "tracks" to cross the bridge taking regrowing axons with them. Importantly, disrupting the organization of the newly formed blood vessels in vivo, either by inhibiting the angiogenic signal or by re-orienting them, compromises Schwann cell directionality resulting in defective nerve repair. This study provides important insights into how the choreography of multiple cell-types is required for the regeneration of an adult tissue.

  15. Influence of Myopia on Size of Optic Nerve Head and Retinal Nerve Fiber Layer Thickness Measured by Spectral Domain Optical Coherence Tomography

    PubMed Central

    Bae, Seok Hyun; Kang, Shin Hee; Feng, Chi Shian; Park, Joohyun; Jeong, Jae Hoon

    2016-01-01

    Purpose To investigate optic nerve head size and retinal nerve fiber layer (RNFL) thickness according to refractive status and axial length. Methods In a cross-sectional study, 252 eyes of 252 healthy volunteers underwent ocular biometry measurement as well as optic nerve head and RNFL imaging by spectral-domain optical coherence tomography. Correlation and linear regression analyses were performed for all subjects. The magnification effect was adjusted by the modified axial length method. Results Disc area and spherical equivalent were positively correlated (r = 0.225, r2 = 0.051, p = 0.000). RNFL thickness showed significant correlations with spherical equivalent (r = 0.359, r2 = 0.129, p = 0.000), axial length (r = -0.262, r2 = 0.069, p = 0.000), disc radius (r = 0.359, r2 = 0.129, p = 0.000), and radius of the scan circle (r = -0.262, r2 = 0.069, p = 0.000). After adjustment for the magnification effect, those relationships were reversed; RNFL thickness showed negative correlation with spherical equivalent and disc radius, and positive correlation with axial length and radius of the scan circle. The distance between the disc margin and the scan circle was closely correlated with RNFL thickness (r = -0.359, r2 = 0.129, p = 0.000), which showed a negative correlation with axial length (r = -0.262, r2 = 0.069, p = 0.000). Conclusions Optic disc radius and RNFL thickness decreased in more severely myopic eyes, but they increased after adjustment for magnification effect. The error due to the magnification effect and optic nerve head size difference might be factors that should be considered when interpreting optical coherence tomography results. PMID:27729753

  16. Anterior approach to the superior mesenteric artery by using nerve plexus hanging maneuver for borderline resectable pancreatic head carcinoma.

    PubMed

    Mizuno, Shugo; Isaji, Shuji; Tanemura, Akihiro; Kishiwada, Masashi; Murata, Yasuhiro; Azumi, Yoshinori; Kuriyama, Naohisa; Usui, Masanobu; Sakurai, Hiroyuki; Tabata, Masami

    2014-06-01

    To achieve R0 resection for pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head, complete resection of the retropancreatic nerve plexus around the superior mesenteric artery (SMA) is thought to be required. Twenty-five patients with borderline resectable right-sided PDAC were divided into two groups after neoadjuvant chemoradiotherapy: those with portal vein (PV) invasion alone (n = 12), and those with invasion of both PV and SMA (n = 13). A tape for guidance was passed in a space ventral to the SMA and behind the pancreatic parenchyma, followed by resection of the pancreatic parenchyma with the splenic vein. Another tape was passed behind the nerve plexus lateral to the hepatic artery and the SMA ventral to the inferior vena cava and the nerve plexus was dissected, resulting in complete resection of the nerve plexus around the SMA. Pathological findings revealed that the rates of R0, R01 (a margin less than 1 mm) and R1 were 58.3 %, 41.7 % and 0 % in PV group, and 53.8 %, 30.8 % and 15.4 % in PV/A group, respectively. The median survival time was 23.3 and 22.8 months in PV and PV/A groups, respectively. The plexus hanging maneuver for PDAC of the pancreatic head achieved complete resection of the retropancreatic nerve plexus around the SMA, helping to secure a negative surgical margin.

  17. The usefulness of multimodal imaging for differentiating pseudopapilloedema and true swelling of the optic nerve head: a review and case series.

    PubMed

    Chiang, Jaclyn; Wong, Elizabeth; Whatham, Andrew; Hennessy, Michael; Kalloniatis, Michael; Zangerl, Barbara

    2015-01-01

    Ophthalmic practitioners have to make a critical differential diagnosis in cases of an elevated optic nerve head. They have to discriminate between pseudopapilloedema (benign elevation of the optic nerve head) and true swelling of the optic nerve head. This decision has significant implications for appropriate patient management. Assessment of the optic disc prior to the advanced imaging techniques that are available today (particularly spectral domain optical coherence tomography and fundus autofluorescence), has mainly used diagnostic tools, such as funduscopy and retinal photography. As these traditional methods rely on the subjective assessment by the clinician, evaluation of the elevated optic nerve head to differentiate pseudopapilloedema from true swelling of the optic nerve head can be a challenge in clinical practice with patients typically referred for further neuroimaging investigation when the diagnosis is uncertain. The use of multimodal ocular imaging tools such as spectral domain optical coherence tomography, short wavelength fundus autofluorescence and ultrasonography, can potentially aid in the differentiation of pseudopapilloedema from true swelling of the optic nerve head, in conjunction with other clinical findings. By doing so, unnecessary patient costs and anxiety in the case of pseudopapilloedema can be reduced, and appropriate urgent referral and management in the case of true swelling of the optic nerve head can be initiated.

  18. Measuring Deformation in the Mouse Optic Nerve Head and Peripapillary Sclera

    PubMed Central

    Nguyen, Cathy; Midgett, Dan; Kimball, Elizabeth C.; Steinhart, Matthew R.; Nguyen, Thao D.; Pease, Mary E.; Oglesby, Ericka N.; Jefferys, Joan L.; Quigley, Harry A.

    2017-01-01

    Purpose To develop an ex vivo explant system using multiphoton microscopy and digital volume correlation to measure the full-field deformation response to intraocular pressure (IOP) change in the peripapillary sclera (PPS) and in the optic nerve head (ONH) astrocytic structure. Methods Green fluorescent protein (GFP)-glutamate transporter-GLT1 (GLT1/GFP) mouse eyes were explanted and imaged with a laser-scanning microscope under controlled inflation. Images were analyzed for regional strains and changes in astrocytic lamina and PPS shape. Astrocyte volume fraction in seven control GLT1/GFP mice was measured. The level of fluorescence of GFP fluorescent astrocytes was compared with glial fibrillary acidic protein (GFAP) labeled astrocytes using immunohistochemistry. Results The ONH astrocytic structure remained stable during 3 hours in explants. Control strain—globally, in the central one-half or two-thirds of the astrocytic lamina—was significantly greater in the nasal-temporal direction than in the inferior-superior or anterior-posterior directions (each P ≤ 0.03, mixed models). The PPS opening (perimeter) in normal eye explants also became wider nasal-temporally than superior-inferiorly during inflation from 10 to 30 mm Hg (P = 0.0005). After 1 to 3 days of chronic IOP elevation, PPS area was larger than in control eyes (P = 0.035), perimeter elongation was 37% less than controls, and global nasal-temporal strain was significantly less than controls (P = 0.007). Astrocyte orientation was altered by chronic IOP elevation, with processes redirected toward the longitudinal axis of the optic nerve. Conclusions The explant inflation test measures the strain response of the mouse ONH to applied IOP. Initial studies indicate regional differences in response to both acute and chronic IOP elevation within the ONH region. PMID:28146237

  19. Crowded optic nerve head evaluation with optical coherence tomography in anterior ischemic optic neuropathy.

    PubMed

    Moghimi, S; Afzali, M; Akbari, M; Ebrahimi, K B; Khodabande, A; Yazdani-Abyaneh, A R; Ghafouri, S N H; Coh, P; Okhravi, S; Fard, M A

    2017-04-07

    PurposeTo characterize the optic nerve head (ONH) structure in patients with non-arteritic anterior ischemic optic neuropathy (NAION) compared to healthy control subjects using spectral domain optical coherence tomography (SD-OCT) via the enhanced depth imaging method.MethodsIn this prospective, cross-sectional, comparative study, we assessed 66 eyes of 33 patients with unilateral NAION and 31 eyes of 31 healthy normal subjects in an academic institution. The peripapillary nerve fiber layer thickness, disc area, and quantitative parameters of the ONH structures, including the Bruch's membrane opening (BMO) area, anterior laminar depth, and prelaminar thickness and depth were compared between the three groups.ResultsLinear mixed model analysis after adjusting for age, sex, and axial length showed that the BMO area was similar in eyes with NAION (1.89±0.33 mm(2)), their fellow eyes (1.85±0.35 mm(2)), and control eyes (1.88±0.37 mm(2); all P>0.99). Anterior laminar depth was also similar in the three groups. The mean prelaminar tissue thickness of the NAION eyes was 445±176 μm, which was thinner than the prelaminar tissue of their unaffected fellow eyes (mean, 539±227 μm, P=0.004), but both were thicker than the prelaminar tissue of the normal subjects (mean 243±145 μm, P=0.001 and P<0.001, respectively).ConclusionsThe thick prelaminar thickness is associated with unilateral NAION in the affected and unaffected eyes.Eye advance online publication, 7 April 2017; doi:10.1038/eye.2017.56.

  20. A Digital Staining Algorithm for Optical Coherence Tomography Images of the Optic Nerve Head

    PubMed Central

    Mari, Jean-Martial; Aung, Tin; Cheng, Ching-Yu; Strouthidis, Nicholas G.; Girard, Michaël J. A.

    2017-01-01

    Purpose To digitally stain spectral-domain optical coherence tomography (OCT) images of the optic nerve head (ONH), and highlight either connective or neural tissues. Methods OCT volumes of the ONH were acquired from one eye of 10 healthy subjects. We processed all volumes with adaptive compensation to remove shadows and enhance deep tissue visibility. For each ONH, we identified the four most dissimilar pixel-intensity histograms, each of which was assumed to represent a tissue group. These four histograms formed a vector basis on which we ‘projected' each OCT volume in order to generate four digitally stained volumes P1 to P4. Digital staining was also verified using a digital phantom, and compared with k-means clustering for three and four clusters. Results Digital staining was able to isolate three regions of interest from the proposed phantom. For the ONH, the digitally stained images P1 highlighted mostly connective tissues, as demonstrated through an excellent contrast increase across the anterior lamina cribrosa boundary (3.6 ± 0.6 times). P2 highlighted the nerve fiber layer and the prelamina, P3 the remaining layers of the retina, and P4 the image background. Further, digital staining was able to separate ONH tissue layers that were not well separated by k-means clustering. Conclusion We have described an algorithm that can digitally stain connective and neural tissues in OCT images of the ONH. Translational Relevance Because connective and neural tissues are considerably altered in glaucoma, digital staining of the ONH tissues may be of interest in the clinical management of this pathology. PMID:28174676

  1. Gender- and Ethnicity-Related Differences in Optic Nerve Head Topography in Healthy Indian and Caucasian Participants.

    PubMed

    Pilat, Anastasia V; Gottlob, Irene; Sheth, Viral; Thomas, Mervyn G; Proudlock, Frank A

    2014-01-01

    We investigated the effect of ethnicity and gender on optic nerve head morphology in healthy subjects using spectral-domain optical coherence tomography (SD-OCT). Thirty-five Indian (i.e. Indian subcontinent) females, 34 Caucasian females, 32 Indian males, and 32 Caucasian males were examined using SD-OCT (Copernicus, Optopol Technology). Disc and rim areas were larger in Caucasian males compared with females but smaller in Indians males compared with females. Indian participants had significantly larger cup areas and volumes without significant differences in retinal nerve fibre layer (RNFL) thicknesses between groups. Gender and ethnicity differences should be considered in assessment of patients.

  2. Gender- and Ethnicity-Related Differences in Optic Nerve Head Topography in Healthy Indian and Caucasian Participants

    PubMed Central

    Pilat, Anastasia V.; Gottlob, Irene; Sheth, Viral; Thomas, Mervyn G.; Proudlock, Frank A.

    2014-01-01

    Abstract We investigated the effect of ethnicity and gender on optic nerve head morphology in healthy subjects using spectral-domain optical coherence tomography (SD-OCT). Thirty-five Indian (i.e. Indian subcontinent) females, 34 Caucasian females, 32 Indian males, and 32 Caucasian males were examined using SD-OCT (Copernicus, Optopol Technology). Disc and rim areas were larger in Caucasian males compared with females but smaller in Indians males compared with females. Indian participants had significantly larger cup areas and volumes without significant differences in retinal nerve fibre layer (RNFL) thicknesses between groups. Gender and ethnicity differences should be considered in assessment of patients. PMID:27928300

  3. Detecting abnormality in optic nerve head images using a feature extraction analysis.

    PubMed

    Zhu, Haogang; Poostchi, Ali; Vernon, Stephen A; Crabb, David P

    2014-07-01

    Imaging and evaluation of the optic nerve head (ONH) plays an essential part in the detection and clinical management of glaucoma. The morphological characteristics of ONHs vary greatly from person to person and this variability means it is difficult to quantify them in a standardized way. We developed and evaluated a feature extraction approach using shift-invariant wavelet packet and kernel principal component analysis to quantify the shape features in ONH images acquired by scanning laser ophthalmoscopy (Heidelberg Retina Tomograph [HRT]). The methods were developed and tested on 1996 eyes from three different clinical centers. A shape abnormality score (SAS) was developed from extracted features using a Gaussian process to identify glaucomatous abnormality. SAS can be used as a diagnostic index to quantify the overall likelihood of ONH abnormality. Maps showing areas of likely abnormality within the ONH were also derived. Diagnostic performance of the technique, as estimated by ROC analysis, was significantly better than the classification tools currently used in the HRT software - the technique offers the additional advantage of working with all images and is fully automated.

  4. Visual loss and optic nerve head swelling in thiamine deficiency without prolonged dietary deficiency

    PubMed Central

    Gratton, Sean M; Lam, Byron L

    2014-01-01

    Visual loss due to optic neuropathy is a rare manifestation of thiamine deficiency. We report a case of a 39-year-old woman with a body mass index (BMI) of 29 kg/m2 who developed visual loss and bilateral optic nerve head swelling after a short, self-limited gastrointestinal illness. She was disoriented and inattentive and had absent ankle jerk reflexes, diminished sensation in both legs below the knees, and marked truncal ataxia. Magnetic resonance imaging (MRI) showed increased T2-signal in the medial thalami and mammillary bodies. The serum thiamine level was 8 nmol/L (normal 8–30). The diagnosis of thiamine deficiency was made, and the patient’s vision and neurologic symptoms improved significantly with intramuscular thiamine treatment. Thiamine deficiency can occur in the absence of an obvious predisposing factor such as alcoholism or low body weight. The clinician must be aware of the factors that govern vitamin availability and maintain a high index of suspicion to make the diagnosis in such cases. PMID:24899800

  5. Bilateral choroidal neovascularization associated with optic nerve head drusen treated by antivascular endothelial growth factor therapy

    PubMed Central

    Delas, Barbara; Almudí, Lorena; Carreras, Anabel; Asaad, Mouafk

    2012-01-01

    Objective To report a good clinical outcome in a patient with bilateral choroidal neovascularization (CNV) associated with optic nerve head drusen (ONHD) treated with intravitreal ranibizumab injection. Methods A 12-year-old girl was referred for loss of right eye vision detected in a routine check-up. Best-corrected visual acuity (BCVA) was hand movements in the right eye and 0.9 in the left eye. Funduscopy revealed the presence of superficial and buried bilateral ONHD, which was confirmed by ultrasonography and computed tomography, and the study was completed with perimetry. The presence of bilateral CNV, active in the right eye, was observed and subsequently confirmed using fluorescein angiography and optical coherence tomography. Results Treatment with two consecutive injections of intravitreal ranibizumab resulted in inactivation of the neovascular membrane with subretinal fluid reabsorption and improved right eye BCVA. After 12 months’ follow-up, this was 20/60 and stable. Conclusion Although there are no published studies of safety in children, antiangiogenic therapy for CNV secondary to ONHD may be useful and safe. A search of the literature produced only one previously reported case of ONHD-associated CNV treated with antivascular endothelial growth factor alone. PMID:22368440

  6. Changes in quantitative 3D shape features of the optic nerve head associated with age

    NASA Astrophysics Data System (ADS)

    Christopher, Mark; Tang, Li; Fingert, John H.; Scheetz, Todd E.; Abramoff, Michael D.

    2013-02-01

    Optic nerve head (ONH) structure is an important biological feature of the eye used by clinicians to diagnose and monitor progression of diseases such as glaucoma. ONH structure is commonly examined using stereo fundus imaging or optical coherence tomography. Stereo fundus imaging provides stereo views of the ONH that retain 3D information useful for characterizing structure. In order to quantify 3D ONH structure, we applied a stereo correspondence algorithm to a set of stereo fundus images. Using these quantitative 3D ONH structure measurements, eigen structures were derived using principal component analysis from stereo images of 565 subjects from the Ocular Hypertension Treatment Study (OHTS). To evaluate the usefulness of the eigen structures, we explored associations with the demographic variables age, gender, and race. Using regression analysis, the eigen structures were found to have significant (p < 0.05) associations with both age and race after Bonferroni correction. In addition, classifiers were constructed to predict the demographic variables based solely on the eigen structures. These classifiers achieved an area under receiver operating characteristic curve of 0.62 in predicting a binary age variable, 0.52 in predicting gender, and 0.67 in predicting race. The use of objective, quantitative features or eigen structures can reveal hidden relationships between ONH structure and demographics. The use of these features could similarly allow specific aspects of ONH structure to be isolated and associated with the diagnosis of glaucoma, disease progression and outcomes, and genetic factors.

  7. Aging changes of the optic nerve head in relation to open angle glaucoma

    PubMed Central

    Garway-Heath, D; Wollstein, G; Hitchings, R

    1997-01-01

    AIMS—To determine the age related changes in optic nerve head structure in a group of normal subjects and assess the significance of any changes in relation to those found in open angle glaucoma.
METHODS—A group of 88 white volunteers and friends and spouses of patients with a normal visual field and normal intraocular pressure was studied. Two different imaging and measurement devices were used (computer assisted planimetry and scanning laser ophthalmoscopy), and the results from each were compared. Measurements were made of the optic disc, optic cup, and neuroretinal rim areas, and the vertical optic disc diameter and cup/disc diameter ratio.
RESULTS—Neuroretinal rim area declined at the rate of between 0.28% and 0.39% per year. Vertical optic cup diameter and optic cup area increased with age. The mean cup/disc diameter ratio increased by about 0.1 between the ages of 30 and 70 years.
CONCLUSIONS—Age related changes are significant and measurable, and should be taken into account when assessing the glaucoma suspect, and when estimating the rate of progression of glaucomatous optic neuropathy in patients with established disease.

 PMID:9486023

  8. Optical fiber head for monitoring of heart rate and blood oxygenation

    NASA Astrophysics Data System (ADS)

    Hoffmann, Kacper; Baranowska, Agata; Zmojda, Jacek; Kochanowicz, Marcin; Dorosz, Dominik

    2016-09-01

    In this article we presented possibility of heart rate and blood oxygenation measurements by classic displacement optical fiber sensor in reflection mode. Based on numerical analysis of sensor head characteristics the optimal construction was developed. Three LED diodes at the wavelengths of 530nm (green), 650nm (red) and 850nm (infrared) were used for determine heart rate and saturation of blood during "in vivo" measurements. Developed sensor head allows noninvasive and continuously monitoring of blood parameters.

  9. Surgical anatomy of the external branch of the superior laryngeal nerve and its clinical significance in head and neck surgery.

    PubMed

    Kochilas, Xenophon; Bibas, Athanasios; Xenellis, John; Anagnostopoulou, Sofia

    2008-03-01

    Injury of the external branch of the superior laryngeal nerve (EBSLN) increases the morbidity following a variety of neck procedures and can have catastrophic consequences in people who use their voice professionally. Identification and preservation of the EBSLN are thus important in thyroidectomy, parathyroidectomy, carotid endarterectomy, and anterior cervical spine procedures, where the nerve is at risk. There are large variations in the anatomical course of the EBSLN, which makes the intraoperative identification of the nerve challenging. The topographic relationship of the EBSLN to the superior thyroid artery and the upper pole of the thyroid gland are considered by many authors to be the key point for identifying the nerve during surgery of the neck. The classifications by Cernea et al. ([1992a] Head Neck 14:380-383; [1992b] Am. J. Surg. 164:634-639) and by Kierner et al. ([1998] Arch. Otolaryngol. Head Neck Surg. 124:301-303), as well as clinically important connections are discussed in detail. Along with sound anatomical knowledge, neuromonitoring is helpful in identifying the EBSLN during neck procedures. The clinical signs of EBSLN injury include hoarseness, decreased voice projection, decreased pitch range, and fatigue after extensive voice use. Videostroboscopy, electromyography, voice analysis, and electroglottography can provide crucial information on the function of the EBSLN following neck surgery.

  10. A Modeling of Cerebral Blood Flow Changes due to Head Motion for fNIRS

    NASA Astrophysics Data System (ADS)

    Takahashi, Kosuke; Tanaka, Takayuki; Nara, Hiroyuki; Kaneko, Shun'ichi; Inoue, Masao; Shimizu, Shunji; Kojima, Satoru

    2013-04-01

    A method is proposed for measuring brain activity during exercises involving head motion by using functional near-infrared spectroscopy (fNIRS), which investigates cerebral hemodynamics. Obtaining measurements during exercise is difficult because cerebral blood flow changes due to the head motion component (HMC), in addition to neural activity. HMC is an undesirable artifact in the measurement of hemodynamic response caused by neural activity, and as such, it must be estimated and eliminated. In our experiments, cerebral blood flow and head motion were measured during repeated passive forward bending of the subjects. Head motion was measured by 3-D motion capture, and HMC was estimated by deriving a relation between head motion and cerebral blood flow, where the pitch angle was found to be suitable for estimating HMC. In this research, an assumption was made that cerebral blood flow caused by neural activity and that caused by postural change were additive, and thus HMC was eliminated by subtraction.

  11. Optic nerve head perfusion in normal eyes and eyes with glaucoma using optical coherence tomography-based microangiography

    PubMed Central

    Chen, Chieh-Li; Bojikian, Karine D.; Gupta, Divakar; Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Kono, Rei; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.

    2016-01-01

    Background To investigate the differences of perfusion in the optic nerve head (ONH) between normal and glaucomatous eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Methods One eye from each subject was scanned with a 68 kHz Cirrus 5000 HD-OCT-based OMAG prototype system centered at the ONH (Carl Zeiss Meditec Inc, Dublin, CA, USA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. En face OMAG images for preLC were generated using signals with highest blood flow signal intensity. ONH perfusion was quantified as flux, vessel area density, and normalized flux within the ONH. Standard t-tests were performed to analyze the ONH perfusion differences between normal and glaucomatous eyes. Linear regression models were constructed to analyze the correlation between ONH perfusion and other clinical measurements. Results Twenty normal and 21 glaucoma subjects were enrolled. Glaucomatous eyes had significantly lower ONH perfusion in preLC in all three perfusion metrics compared to normal eyes (P≤0.0003). Significant correlations between ONH perfusion and disease severity as well as structural changes were detected in glaucomatous eyes (P≤0.012). Conclusions ONH perfusion detected by OMAG showed significant differences between glaucoma and normal controls and was significantly correlated with disease severity and structural defects in glaucomatous eyes. ONH perfusion measurement using OMAG may provide useful information for detection and monitoring of glaucoma. PMID:27190764

  12. Optic nerve head and intraocular pressure in the guinea pig eye.

    PubMed

    Ostrin, Lisa A; Wildsoet, Christine F

    2016-05-01

    The guinea pig is becoming an increasingly popular model for studying human myopia, which carries an increased risk of glaucoma. As a step towards understanding this association, this study sought to characterize the normal, developmental intraocular pressure (IOP) profiles, as well as the anatomy of the optic nerve head (ONH) and adjacent sclera of young guinea pigs. IOP was tracked in pigmented guinea pigs up to 3 months of age. One guinea pig was imaged in vivo with OCT and one with a fundus camera. The eyes of pigmented and albino guinea pigs (ages 2 months) were enucleated and sections from the posterior segment, including the ONH and surrounding sclera, processed for histological analyses - either hematoxylin and eosin (H&E) staining of paraffin embedded, sectioned tissue (n = 1), or cryostat sectioned tissue, processed for immunohistochemistry (n = 3), using primary antibodies against collagen types I-V, elastin, fibronectin and glial fibrillary acidic protein (GFAP). Transmission and scanning electron microscopy (TEM, SEM) studies of ONHs were also undertaken (n = 2 & 5 respectively). Mean IOPs ranged from 17.33 to 22.7 mmHg, increasing slightly across the age range studied, and the IOPs of individual animals also exhibited diurnal variations, peaking in the early morning (mean of 25.8, mmHg, ∼9 am), and decreasing across the day. H&E-stained sections showed retinal ganglion cell axons organized into fascicles in the prelaminar and laminar region of the ONHs, with immunostained sections revealing collagen types I, III, IV and V, as well as elastin, GFAP and fibronectin in the ONHs. SEM revealed a well-defined lamina cribrosa (LC), with radially-oriented collagen beams. TEM revealed collagen fibrils surrounding non-myelinated nerve fiber bundles in the LC region, with myelination and decreased collagen posterior to the LC. The adjacent sclera comprised mainly crimped collagen fibers in a crisscross arrangement. Both the sclera and LC were

  13. Interaction of nanoparticles of ferric oxide with brain nerve terminals and blood platelets

    NASA Astrophysics Data System (ADS)

    Borisova, Tatiana; Krisanova, Natalia; Sivko, Roman; Borisov, Arseniy

    2012-07-01

    Nanoparticles of ferric oxide are the components of Lunar and Martian soil simulants. The observations suggest that exposure to Lunar soli simulant can be deleterious to human physiology and the components of lunar soil may be internalized by lung epithelium and may overcome the blood-brain barrier. The study focused on the effects of nanoparticles of ferric oxide on the functional state of rat brain nerve terminals (synaptosomes) and rabbit blood platelets. Using photon correlation spectroscopy, we demonstrated the binding of nanoparticles of ferric oxide with nerve terminals and platelets. Nanoparticles did not depolarize the plasma membrane of nerve terminals and platelets that was shown by fluorimetry with potential-sensitive fluorescent dye rhodamine 6G. Using pH-sensitive fluorescent dye acridine orange, we revealed that the acidification of synaptic vesicles of nerve terminals and secretory granules of platelets did not change in the presence of nanoparticles. The initial velocity of uptake of excitatory neurotransmitter glutamate was not influenced by nanoparticles of ferric oxide, whereas glutamate binding to nerve terminals was altered. Thus, it was suggested that nanoparticles of ferric oxide might disturb glutamate transport in the mammalian CNS.

  14. The Effects of Impact Vibration on Peripheral Blood Vessels and Nerves

    PubMed Central

    KRAJNAK, Kristine M.; WAUGH, Stacey; JOHNSON, Claud; MILLER, G. Roger; XU, Xueyan; WARREN, Christopher; DONG, Ren G.

    2013-01-01

    Research regarding the risk of developing hand-arm vibration syndrome after exposure to impact vibration has produced conflicting results. This study used an established animal model of vibration-induced dysfunction to determine how exposure to impact vibration affects peripheral blood vessels and nerves. The tails of male rats were exposed to a single bout of impact vibration (15 min exposure, at a dominant frequency of 30 Hz and an unweighted acceleration of approximately 345 m/s2) generated by a riveting hammer. Responsiveness of the ventral tail artery to adrenoreceptor-mediated vasoconstriction and acetylcholine-mediated re-dilation was measured ex vivo. Ventral tail nerves and nerve endings in the skin were assessed using morphological and immunohistochemical techniques. Impact vibration did not alter vascular responsiveness to any factors or affect trunk nerves. However, 4 days following exposure there was an increase in protein-gene product (PGP) 9.5 staining around hair follicles. A single exposure to impact vibration, with the exposure characteristics described above, affects peripheral nerves but not blood vessels. PMID:24077447

  15. Importance of rostral ventrolateral medulla neurons in determining efferent sympathetic nerve activity and blood pressure.

    PubMed

    Kumagai, Hiroo; Oshima, Naoki; Matsuura, Tomokazu; Iigaya, Kamon; Imai, Masaki; Onimaru, Hiroshi; Sakata, Katsufumi; Osaka, Motohisa; Onami, Toshiko; Takimoto, Chie; Kamayachi, Tadashi; Itoh, Hiroshi; Saruta, Takao

    2012-02-01

    Accentuated sympathetic nerve activity (SNA) is a risk factor for cardiovascular events. In this review, we investigate our working hypothesis that potentiated activity of neurons in the rostral ventrolateral medulla (RVLM) is the primary cause of experimental and essential hypertension. Over the past decade, we have examined how RVLM neurons regulate peripheral SNA, how the sympathetic and renin-angiotensin systems are correlated and how the sympathetic system can be suppressed to prevent cardiovascular events in patients. Based on results of whole-cell patch-clamp studies, we report that angiotensin II (Ang II) potentiated the activity of RVLM neurons, a sympathetic nervous center, whereas Ang II receptor blocker (ARB) reduced RVLM activities. Our optical imaging demonstrated that a longitudinal rostrocaudal column, including the RVLM and the caudal end of ventrolateral medulla, acts as a sympathetic center. By organizing and analyzing these data, we hope to develop therapies for reducing SNA in our patients. Recently, 2-year depressor effects were obtained by a single procedure of renal nerve ablation in patients with essential hypertension. The ablation injured not only the efferent renal sympathetic nerves but also the afferent renal nerves and led to reduced activities of the hypothalamus, RVLM neurons and efferent systemic sympathetic nerves. These clinical results stress the importance of the RVLM neurons in blood pressure regulation. We expect renal nerve ablation to be an effective treatment for congestive heart failure and chronic kidney disease, such as diabetic nephropathy.

  16. Increased mitochondrial fission and volume density by blocking glutamate excitotoxicity protect glaucomatous optic nerve head astrocytes.

    PubMed

    Ju, Won-Kyu; Kim, Keun-Young; Noh, You Hyun; Hoshijima, Masahiko; Lukas, Thomas J; Ellisman, Mark H; Weinreb, Robert N; Perkins, Guy A

    2015-05-01

    Abnormal structure and function of astrocytes have been observed within the lamina cribrosa region of the optic nerve head (ONH) in glaucomatous neurodegeneration. Glutamate excitotoxicity-mediated mitochondrial alteration has been implicated in experimental glaucoma. However, the relationships among glutamate excitotoxicity, mitochondrial alteration and ONH astrocytes in the pathogenesis of glaucoma remain unknown. We found that functional N-methyl-d-aspartate (NMDA) receptors (NRs) are present in human ONH astrocytes and that glaucomatous human ONH astrocytes have increased expression levels of NRs and the glutamate aspartate transporter. Glaucomatous human ONH astrocytes exhibit mitochondrial fission that is linked to increased expression of dynamin-related protein 1 and its phosphorylation at Serine 616. In BAC ALDH1L1 eGFP or Thy1-CFP transgenic mice, NMDA treatment induced axon loss as well as hypertrophic morphology and mitochondrial fission in astrocytes of the glial lamina. In human ONH astrocytes, NMDA treatment in vitro triggered mitochondrial fission by decreasing mitochondrial length and number, thereby reducing mitochondrial volume density. However, blocking excitotoxicity by memantine (MEM) prevented these alterations by increasing mitochondrial length, number and volume density. In glaucomatous DBA/2J (D2) mice, blocking excitotoxicity by MEM inhibited the morphological alteration as well as increased mitochondrial number and volume density in astrocytes of the glial lamina. However, blocking excitotoxicity decreased autophagosome/autolysosome volume density in both astrocytes and axons in the glial lamina of glaucomatous D2 mice. These findings provide evidence that blocking excitotoxicity prevents ONH astrocyte dysfunction in glaucomatous neurodegeneration by increasing mitochondrial fission, increasing mitochondrial volume density and length, and decreasing autophagosome/autolysosome formation. GLIA 2015;63:736-753.

  17. The effect of cataract surgery on imaging optic nerve head topography with the Heidelberg Retina Tomograph.

    PubMed

    Falck, Aura A K; Saarela, Ville

    2012-06-14

    Purpose. To determine whether phacoemulsification cataract surgery with intraocular lens (IOL) implantation interferes with measuring optic nerve head (ONH) topography using the Heidelberg Retina Tomograph (HRT). Methods. The study population consisted of 31 women and 12 men aged 63-81 years with no previous history of eye diseases, surgery, laser procedures, or medication. The patients underwent first eye cataract surgery for senile cataract. The HRT II with software version 1.6 was used to obtain 3-dimensional images of the ONH as a part of a comprehensive ocular examination. The quality of the HRT image was assessed using topography standard deviation (TSD). Topography measurements are considered to be unreliable if TSD is more than 50 µm. Re-examination took place 1 month after surgery. Results. Before surgery, the topography measurements were unreliable in 35% (15/43) of the eyes; in 3 of these cases, ONH topography could not be calculated at all. One month after cataract surgery, the ONH topography could be calculated in all eyes and only one displayed unreliable topography measurements. The mean TSD was 40 µm before and 22 µm after surgery when calculated for all eyes with measurable topographies. The change in TSD was statistically significant (p<0.0005). The image alignment between the HRT examinations before and after surgery was excellent in 67% (26/39). Magnification changes occurred in 21% (8/39). Conclusions. Phacoemulsification cataract surgery with IOL implantation improves the image quality of the HRT. However, because of magnification changes and image misalignment, HRT follow-up of the ONH after cataract surgery is often unreliable.

  18. Increased Mitochondrial Fission and Volume Density by Blocking Glutamate Excitotoxicity Protect Glaucomatous Optic Nerve Head Astrocytes

    PubMed Central

    Ju, Won-Kyu; Kim, Keun-Young; Noh, You Hyun; Hoshijima, Masahiko; Lukas, Thomas J; Ellisman, Mark H; Weinreb, Robert N; Perkins, Guy A

    2015-01-01

    Abnormal structure and function of astrocytes have been observed within the lamina cribrosa region of the optic nerve head (ONH) in glaucomatous neurodegeneration. Glutamate excitotoxicity-mediated mitochondrial alteration has been implicated in experimental glaucoma. However, the relationships among glutamate excitotoxicity, mitochondrial alteration and ONH astrocytes in the pathogenesis of glaucoma remain unknown. We found that functional N-methyl-d-aspartate (NMDA) receptors (NRs) are present in human ONH astrocytes and that glaucomatous human ONH astrocytes have increased expression levels of NRs and the glutamate aspartate transporter. Glaucomatous human ONH astrocytes exhibit mitochondrial fission that is linked to increased expression of dynamin-related protein 1 and its phosphorylation at Serine 616. In BAC ALDH1L1 eGFP or Thy1-CFP transgenic mice, NMDA treatment induced axon loss as well as hypertrophic morphology and mitochondrial fission in astrocytes of the glial lamina. In human ONH astrocytes, NMDA treatment in vitro triggered mitochondrial fission by decreasing mitochondrial length and number, thereby reducing mitochondrial volume density. However, blocking excitotoxicity by memantine (MEM) prevented these alterations by increasing mitochondrial length, number and volume density. In glaucomatous DBA/2J (D2) mice, blocking excitotoxicity by MEM inhibited the morphological alteration as well as increased mitochondrial number and volume density in astrocytes of the glial lamina. However, blocking excitotoxicity decreased autophagosome/autolysosome volume density in both astrocytes and axons in the glial lamina of glaucomatous D2 mice. These findings provide evidence that blocking excitotoxicity prevents ONH astrocyte dysfunction in glaucomatous neurodegeneration by increasing mitochondrial fission, increasing mitochondrial volume density and length, and decreasing autophagosome/autolysosome formation. PMID:25557093

  19. Independent effects of heart-head distance and caudal blood pooling on blood pressure regulation in aquatic and terrestrial snakes.

    PubMed

    Seymour, Roger S; Arndt, Joachim O

    2004-03-01

    Changes in orientation in a gravitational field markedly alter the patterns of blood pressure and flow in animals, especially tall or long ones such as giraffes or snakes. Vertical orientation tends to reduce blood flow and pressure in the head for two major reasons. First, the increased vertical blood column above the heart creates a gravitational hydrostatic pressure against which the heart must work. Second, expansion of dependent vessels in the lower extremities causes blood pooling and reduces return of venous blood to the heart, thereby lowering flow and pressure. For most animals, it is difficult to separate these two effects, but snakes offer the possibility of bending the animal in the region of the heart and manipulating the two ends of the body independently. We studied baroregulatory responses in terrestrial pythons (Liasis fuscus) and aquatic file snakes (Acrochordus arafurae) by tilting only the front or rear parts and then the whole animal. Changes in head blood pressure during partial tilts added up to the change during full tilt. The vertical distance to the head had twice as much influence on head blood pressure than did blood pooling in the pythons and four times as much in file snakes. This accounts for the cephalad location of the heart in terrestrial species compared with aquatic ones.

  20. Blood-nerve barrier dysfunction contributes to the generation of neuropathic pain and allows targeting of injured nerves for pain relief.

    PubMed

    Lim, Tony K Y; Shi, Xiang Qun; Martin, Hiliary Claire; Huang, Hao; Luheshi, Giamal; Rivest, Serge; Zhang, Ji

    2014-05-01

    The blood-nerve barrier (BNB) is a selectively permeable barrier that creates an immunologically and biochemically privileged space for peripheral axons and supporting cells. The breakdown of the BNB allows access of blood-borne (hematogenous) cells and molecules to the endoneurium to engage in the local inflammatory cascade. This process was examined in a mouse model of trauma-associated neuropathic pain. The impact of nerve injury-triggered opening of the BNB in the development of chronic pain behavior was investigated. Partial ligation of the sciatic nerve led to a long-lasting disruption of the BNB distal to the site of injury. Vascular endothelial growth factor (VEGF) was expressed by resident macrophages after nerve injury. Intraneural injection of VEGF decreased mechanical thresholds while opening the BNB. Serum from nerve-injured or lipopolysaccharide-treated animals elicited mechanical allodynia in naive animals, when allowed to bypass the BNB by intraneural injection. Intraneural injection of fibrinogen, a clotting protein in plasma that was found to deposit in the nerve after nerve injury, also produced a decrease in mechanical thresholds when introduced into naive nerves. These results demonstrate that blood-borne molecules may play a role in the generation of neuropathic pain, suggesting that pain may be driven from infection or injury, at a distance from the nervous system. Furthermore, the breakdown of the BNB in neuropathic conditions was exploited to permit the entry of analgesic molecules that typically cannot pass the BNB, such as ProToxin-II, a BNB-impermeable Nav1.7 inhibitor. Therapeutics utilizing this mechanism could have selective access to injured nerves over healthy tissues.

  1. On the vagal cardiac nerves, with special reference to the early evolution of the head-trunk interface.

    PubMed

    Higashiyama, Hiroki; Hirasawa, Tatsuya; Oisi, Yasuhiro; Sugahara, Fumiaki; Hyodo, Susumu; Kanai, Yoshiakira; Kuratani, Shigeru

    2016-09-01

    The vagus nerve, or the tenth cranial nerve, innervates the heart in addition to other visceral organs, including the posterior visceral arches. In amniotes, the anterior and posterior cardiac branches arise from the branchial and intestinal portions of the vagus nerve to innervate the arterial and venous poles of the heart, respectively. The evolution of this innervation pattern has yet to be elucidated, due mainly to the lack of morphological data on the vagus in basal vertebrates. To investigate this topic, we observed the vagus nerves of the lamprey (Lethenteron japonicum), elephant shark (Callorhinchus milii), and mouse (Mus musculus), focusing on the embryonic patterns of the vagal branches in the venous pole. In the lamprey, no vagus branch was found in the venous pole throughout development, whereas the arterial pole was innervated by a branch from the branchial portion. In contrast, the vagus innervated the arterial and venous poles in the mouse and elephant shark. Based on the morphological patterns of these branches, the venous vagal branches of the mouse and elephant shark appear to belong to the intestinal part of the vagus, implying that the cardiac nerve pattern is conserved among crown gnathostomes. Furthermore, we found a topographical shift of the structures adjacent to the venous pole (i.e., the hypoglossal nerve and pronephros) between the extant gnathostomes and lamprey. Phylogenetically, the lamprey morphology is likely to be the ancestral condition for vertebrates, suggesting that the evolution of the venous branch occurred early in the gnathostome lineage, in parallel with the remodeling of the head-trunk interfacial domain during the acquisition of the neck. J. Morphol. 277:1146-1158, 2016. © 2016 Wiley Periodicals, Inc.

  2. Blood nerve barrier in rat and cellular mechanisms of lead-induced segmental demyelination

    SciTech Connect

    Dyck, P.J.; Windebank, A.J.; Low, P.A.; Baumann, W.J.

    1980-11-01

    Feeding of lead carbonate to rats causes widespread and reproducible segmental de- and remyelination of myelinated fibers (MFs) of peripheral nerve. Such segmental demyelination might be explained by increased permeability of endoneurial capillaries to serum containing protein-bound lead. The perineurium of control and lead nerves was impermeable to fluorescein-labeled bovine albumin (FBA) and to horseradish peroxidase (HRP). Epineurial capillaries in both conditions allowed HRP to pass freely between and, to a lesser extent, through endothelial cells. Contrary to expectation, flooding of the endoneurium with HRP was seen in only 1 of 36 tissue blocks of lead nerves from rats fed 4% lead carbonate for 7 1/2 and 12 weeks. Abundant HRP reaction product was seen in the epineurium in more than half of these tissue blocks. HRP was not generally found in endoneurial fluid, even in lead nerves with marked edema and widespread segmental de- and remyelination. These findings are against a massive breakdown of the blood nerve barrier. These studies suggest that there may be an increased transfer of HRP through endoneurial cells in lead neuropathy.

  3. Variations of the sciatic nerve anatomy and blood supply in the gluteal region: a review of the literature.

    PubMed

    Kanawati, Andrew James

    2014-11-01

    Variations of the sciatic nerve anatomy and blood supply are complex and largely not dealt with in common anatomy texts. Variations of the sciatic nerve anatomy can be divided into the height of division of its branches, relation of the branches to the piriformis muscle, and its blood supply. These variations should be well known to any surgeon operating in this anatomical region. It is unknown whether these variations increase the risk of surgical injury and consequent morbidity. This paper will review the current knowledge regarding anatomical variations of the sciatic nerve and its blood supply.

  4. A lab-on-a-chip for detection of nerve agent sarin in blood.

    PubMed

    Tan, Hsih Yin; Loke, Weng Keong; Tan, Yong Teng; Nguyen, Nam-Trung

    2008-06-01

    Sarin (C(4)H(10)FO(2)P,O-isopropyl methylphosphonofluoridate) is a colourless, odourless and highly toxic phosphonate that acts as a cholinesterase inhibitor and disrupts neuromuscular transmission. Sarin and related phosphonates are chemical warfare agents, and there is a possibility of their application in a military or terrorist attack. This paper reports a lab-on-a-chip device for detecting a trace amount of sarin in a small volume of blood. The device should allow early detection of sarin exposure during medical triage to differentiate between those requiring medical treatment from mass psychogenic illness cases. The device is based on continuous-flow microfluidics with sequential stages for lysis of whole blood, regeneration of free nerve agent from its complex with blood cholinesterase, protein precipitation, filtration, enzyme-assisted reaction and optical detection. Whole blood was first mixed with a nerve gas regeneration agent, followed by a protein precipitation step. Subsequently, the lysed product was filtered on the chip in two steps to remove particulates and fluoride ions. The filtered blood sample was then tested for trace levels of regenerated sarin using immobilised cholinesterase on the chip. Activity of immobilised cholinesterase was monitored by the enzyme-assisted reaction of a substrate and reaction of the end-product with a chromophore. Resultant changes in chromophore-induced absorbance were recorded on the chip using a Z-shaped optical window. Loss of enzyme activity obtained prior and after passage of the treated blood sample, as shown by a decrease in recorded absorbance values, indicates the presence of either free or regenerated sarin in the blood sample. The device was fabricated in PMMA (polymethylmethacrylate) using CO(2)-laser micromachining. This paper reports the testing results of the different stages, as well as the whole device with all stages in the required assay sequence. The results demonstrate the potential use of a

  5. Transfer of 45Ca and 36Cl at the blood-nerve barrier of the sciatic nerve in rats fed low or high calcium diets

    SciTech Connect

    Wadhwani, K.C.; Murphy, V.A.; Rapoport, S.I. )

    1991-04-01

    Unidirectional fluxes of 45Ca, 36Cl, and of (3H)mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma (Ca) was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 {plus minus} 0.04 and 0.40 {plus minus} 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). The authors results show no evidence for concentration-dependent transport of Ca over a plasma (Ca) range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.

  6. Radiation treatment inhibits monocyte entry into the optic nerve head and prevents neuronal damage in a mouse model of glaucoma.

    PubMed

    Howell, Gareth R; Soto, Ileana; Zhu, Xianjun; Ryan, Margaret; Macalinao, Danilo G; Sousa, Gregory L; Caddle, Lura B; MacNicoll, Katharine H; Barbay, Jessica M; Porciatti, Vittorio; Anderson, Michael G; Smith, Richard S; Clark, Abbot F; Libby, Richard T; John, Simon W M

    2012-04-01

    Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve.

  7. Renal sympathetic nerve, blood flow, and epithelial transport responses to thermal stress.

    PubMed

    Wilson, Thad E

    2017-05-01

    Thermal stress is a profound sympathetic stress in humans; kidney responses involve altered renal sympathetic nerve activity (RSNA), renal blood flow, and renal epithelial transport. During mild cold stress, RSNA spectral power but not total activity is altered, renal blood flow is maintained or decreased, and epithelial transport is altered consistent with a sympathetic stress coupled with central volume loaded state. Hypothermia decreases RSNA, renal blood flow, and epithelial transport. During mild heat stress, RSNA is increased, renal blood flow is decreased, and epithelial transport is increased consistent with a sympathetic stress coupled with a central volume unloaded state. Hyperthermia extends these directional changes, until heat illness results. Because kidney responses are very difficult to study in humans in vivo, this review describes and qualitatively evaluates an in vivo human skin model of sympathetically regulated epithelial tissue compared to that of the nephron. This model utilizes skin responses to thermal stress, involving 1) increased skin sympathetic nerve activity (SSNA), decreased skin blood flow, and suppressed eccrine epithelial transport during cold stress; and 2) increased SSNA, skin blood flow, and eccrine epithelial transport during heat stress. This model appears to mimic aspects of the renal responses. Investigations of skin responses, which parallel certain renal responses, may aid understanding of epithelial-sympathetic nervous system interactions during cold and heat stress.

  8. Sensory stimulation for lowering intraocular pressure, improving blood flow to the optic nerve and neuroprotection in primary open-angle glaucoma.

    PubMed

    Rom, Edith

    2013-12-01

    Primary open-angle glaucoma is a group of optic neuropathies that can lead to irreversible blindness. Sensory stimulation in the form of acupuncture or ear acupressure may contribute to protecting patients from blindness when used as a complementary method to orthodox treatment in the form of drops, laser or surgery. The objective of this article is to provide a narrative overview of the available literature up to July 2012. It summarises reported evidence on the potential beneficial effects of sensory stimulation for glaucoma. Sensory stimulation appears to significantly enhance the pressure-lowering effect of orthodox treatments. Studies suggest that it may also improve blood flow to the eye and optic nerve head. Furthermore, it may play a role in neuroprotection through regulating nerve growth factor and brain-derived neurotrophic factor and their receptors, thereby encouraging the survival pathway in contrast to the pathway to apoptosis. Blood flow and neuroprotection are areas that are not directly influenced by orthodox treatment modalities. Numerous different treatment protocols were used to investigate the effect of sensory stimulation on intraocular pressure, blood flow or neuroprotection of the retina and optic nerve in the animal model and human pilot studies. Objective outcomes were reported to have been evaluated with Goldmann tonometry, Doppler ultrasound techniques and electrophysiology (pattern electroretinography, visually evoked potentials), and supported with histological studies in the animal model. Taken together, reported evidence from these studies strongly suggests that sensory stimulation is worthy of further research.

  9. Intranasal nerve growth factor bypasses the blood-brain barrier and affects spinal cord neurons in spinal cord injury

    PubMed Central

    Aloe, Luigi; Bianchi, Patrizia; De Bellis, Alberto; Soligo, Marzia; Rocco, Maria Luisa

    2014-01-01

    The purpose of this work was to investigate whether, by intranasal administration, the nerve growth factor bypasses the blood-brain barrier and turns over the spinal cord neurons and if such therapeutic approach could be of value in the treatment of spinal cord injury. Adult Sprague-Dawley rats with intact and injured spinal cord received daily intranasal nerve growth factor administration in both nostrils for 1 day or for 3 consecutive weeks. We found an increased content of nerve growth factor and enhanced expression of nerve growth factor receptor in the spinal cord 24 hours after a single intranasal administration of nerve growth factor in healthy rats, while daily treatment for 3 weeks in a model of spinal cord injury improved the deficits in locomotor behaviour and increased spinal content of both nerve growth factor and nerve growth factor receptors. These outcomes suggest that the intranasal nerve growth factor bypasses blood-brain barrier and affects spinal cord neurons in spinal cord injury. They also suggest exploiting the possible therapeutic role of intranasally delivered nerve growth factor for the neuroprotection of damaged spinal nerve cells. PMID:25206755

  10. Accelerated Aging in Glaucoma: Immunohistochemical Assessment of Advanced Glycation End Products in the Human Retina and Optic Nerve Head

    PubMed Central

    Tezel, Gülgün; Luo, Cheng; Yang, Xiangjun

    2008-01-01

    PURPOSE This study aimed to determine the association between advanced glycation end products (AGEs) and glaucoma based on the known synergism between oxidative stress with AGEs and the evidence of oxidative stress during glaucomatous neurodegeneration. METHODS The extent and cellular localization of immunolabeling for AGEs and their receptor, RAGE, were determined in histologic sections of the retina and optic nerve head obtained from 38 donor eyes with glaucoma and 30 eyes from age-matched donors without glaucoma. RESULTS The extent of AGE and RAGE immunolabeling was greater in older than in younger donor eyes. However, compared with age-matched controls, an enhanced accumulation of AGEs and an up-regulation of RAGE were detectable in the glaucomatous retina and optic nerve head. Although some retinal ganglion cells (RGCs) and glia exhibited intracellular immunolabeling for AGEs, increased AGE immunolabeling in glaucomatous eyes was predominantly extracellular and included laminar cribriform plates in the optic nerve head. Some RAGE immunolabeling was detectable on RGCs; however, increased RAGE immunolabeling in glaucomatous eyes was predominant on glial cells, primarily Müller cells. CONCLUSIONS Given that the generation of AGEs is an age-dependent event, increased AGE accumulation in glaucomatous tissues supports that an accelerated aging process accompanies neurodegeneration in glaucomatous eyes. One of the potential consequences of AGE accumulation in glaucomatous eyes appears to be its contribution to increased rigidity of the lamina cribrosa. The presence of RAGE on RGCs and glia also makes them susceptible to AGE-mediated events through receptor-mediated signaling, which may promote cell death or dysfunction during glaucomatous neurodegeneration. PMID:17325164

  11. [Oxidative modification of rat blood proteins after destruction capsaicin-sensitive nerve and change of nitric oxide level].

    PubMed

    Tolochko, Z S; Spiridonov, V K

    2010-01-01

    Content of blood protein carbonyl derivates in rats are determined to assess oxidative modification of protein after destruction of capsaicin-sensitive nerve and change of nitric oxide (NO) level. Deafferentation of these nerves produces increase of the protein carbonyl derivates content. The increase of NO by L-arginine does not affect protein oxidative destruction produced by ablation of capsaicin-sensitive nerve. Selective inhibitor of neuronal synthase NO (n-NOS) 7-nitroindazole (7-NI) results in similar effect. L-NAME increased oxidative destruction of proteins. These results demonstrate that deafferentation of capsaicin-sensitive nerve induces oxidative destruction of proteins. NO has party to mediating oxidative modification of proteins.

  12. Human umbilical cord blood-derived stem cells and brain-derived neurotrophic factor protect injured optic nerve: viscoelasticity characterization

    PubMed Central

    Lv, Xue-man; Liu, Yan; Wu, Fei; Yuan, Yi; Luo, Min

    2016-01-01

    The optic nerve is a viscoelastic solid-like biomaterial. Its normal stress relaxation and creep properties enable the nerve to resist constant strain and protect it from injury. We hypothesized that stress relaxation and creep properties of the optic nerve change after injury. More-over, human brain-derived neurotrophic factor or umbilical cord blood-derived stem cells may restore these changes to normal. To validate this hypothesis, a rabbit model of optic nerve injury was established using a clamp approach. At 7 days after injury, the vitreous body re-ceived a one-time injection of 50 μg human brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood-derived stem cells. At 30 days after injury, stress relaxation and creep properties of the optic nerve that received treatment had recovered greatly, with patho-logical changes in the injured optic nerve also noticeably improved. These results suggest that human brain-derived neurotrophic factor or umbilical cord blood-derived stem cell intervention promotes viscoelasticity recovery of injured optic nerves, and thereby contributes to nerve recovery. PMID:27212930

  13. Human umbilical cord blood-derived stem cells and brain-derived neurotrophic factor protect injured optic nerve: viscoelasticity characterization.

    PubMed

    Lv, Xue-Man; Liu, Yan; Wu, Fei; Yuan, Yi; Luo, Min

    2016-04-01

    The optic nerve is a viscoelastic solid-like biomaterial. Its normal stress relaxation and creep properties enable the nerve to resist constant strain and protect it from injury. We hypothesized that stress relaxation and creep properties of the optic nerve change after injury. More-over, human brain-derived neurotrophic factor or umbilical cord blood-derived stem cells may restore these changes to normal. To validate this hypothesis, a rabbit model of optic nerve injury was established using a clamp approach. At 7 days after injury, the vitreous body re-ceived a one-time injection of 50 μg human brain-derived neurotrophic factor or 1 × 10(6) human umbilical cord blood-derived stem cells. At 30 days after injury, stress relaxation and creep properties of the optic nerve that received treatment had recovered greatly, with patho-logical changes in the injured optic nerve also noticeably improved. These results suggest that human brain-derived neurotrophic factor or umbilical cord blood-derived stem cell intervention promotes viscoelasticity recovery of injured optic nerves, and thereby contributes to nerve recovery.

  14. Relation with preoperative fructosamine and autonomic nerve function and blood pressure during anesthesia in diabetics: a retrospective study.

    PubMed

    Goto, Y; Sugiura, Y; Yanagimoto, M; Yasuda, Y; Suzuki, H; Hasegawa, K

    1999-01-01

    Many diabetics may have a high risk involving the cardiovascular system. In an attempt to predict the intraoperative risks of diabetics during anesthesia, we evaluated retrospectively the relationship among the biochemical assay or autonomic nerve function obtained as parts of the preoperative examination, and the blood pressure changes relating to the stimulation of intubation and extubation for anesthesia. In 40 diabetic surgical patients examined the biochemical assay (HbA1c, fructosamine level and blood glucose level) beforehand, the autonomic nerve function was quantified preoperatively by analysis of ECG R-R variability recorded in supine and subsequent standing position using an HRV analyzer, and some parameters of autonomic nerve function especially responsive sympathetic nerve activities were obtained. We assessed the correlation with systolic blood pressure changes in these cases at intubation for general anesthesia comparing to similar conditioned 40 non-diabetics. A diabetics with low vagal activity became larger systolic blood pressure afterdrop at tracheal intubation for anesthesia (r=0.513, p<0.001). Otherwise the blood pressure afterdrop at extubation became larger in a non-diabetics with high sympathetic activity (r=0.502, p<0.001). The preoperative fructosamine concentration in diabetics correlated positively with the responsive sympathetic nerve irritability index; "mRR(sup)-RRmin(std)" (r=0.432, p<0.05) and the responsive sympathetic nerve excitability index; "mRR(sup-std)" (r=0.448, p<0.05). However HbA1c had no correlation with these parameters of autonomic nerve function and blood pressure rise at tracheal intubation. Because of above correlation with blood pressure rise at intubation for anesthesia induction, the preoperative fructosamine examination and the responsive sympathetic nerve function test must be useful preoperative examination for detection of the unexpected heart events of diabetic patients during operation.

  15. Characterizing biological variability in livestock blood cholinesterase activity for biomonitoring organophosphate nerve agent exposure

    SciTech Connect

    Halbrook, R.S.; Shugart, L.R.; Watson, A.P.; Munro, N.B.; Linnabary, R.D. )

    1992-09-01

    A biomonitoring protocol, using blood cholinesterase (ChE) activity in livestock as a monitor of potential organophosphate nerve agent exposure during the planned destruction of US unitary chemical warfare agent stockpiles, is described. The experimental design included analysis of blood ChE activity in individual healthy sheep, horses, and dairy and beef cattle during a 10- to 12-month period. Castrated and sexually intact males, pregnant and lactating females, and adult and immature animals were examined through at least one reproductive cycle. The same animals were used throughout the period of observation and were not exposed to ChE-inhibiting organophosphate or carbamate compounds. A framework for an effective biomonitoring protocol within a monitoring area includes establishing individual baseline blood ChE activity for a sentinel group of 6 animals on the bases of blood samples collected over a 6-month period, monthly collection of blood samples for ChE-activity determination during monitoring, and selection of adult animals as sentinels. Exposure to ChE-inhibiting compounds would be suspected when all blood ChE activity of all animals within the sentinel group are decreased greater than 20% from their own baseline value. Sentinel species selection is primarily a logistical and operational concern; however, sheep appear to be the species of choice because within-individual baseline ChE activity and among age and gender group ChE activity in sheep had the least variability, compared with data from other species. This protocol provides an effective and efficient means for detecting abnormal depressions in blood ChE activity in livestock and can serve as a valuable indicator of the extent of actual plume movement and/or deposition in the event of organophosphate nerve agent release.

  16. The role of blood vessels in high-resolution volume conductor head modeling of EEG

    PubMed Central

    Fiederer, L.D.J.; Vorwerk, J.; Lucka, F.; Dannhauer, M.; Yang, S.; Dümpelmann, M.; Schulze-Bonhage, A.; Aertsen, A.; Speck, O.; Wolters, C.H.; Ball, T.

    2016-01-01

    Reconstruction of the electrical sources of human EEG activity at high spatiotemporal accuracy is an important aim in neuroscience and neurological diagnostics. Over the last decades, numerous studies have demonstrated that realistic modeling of head anatomy improves the accuracy of source reconstruction of EEG signals. For example, including a cerebrospinal fluid compartment and the anisotropy of white matter electrical conductivity were both shown to significantly reduce modeling errors. Here, we for the first time quantify the role of detailed reconstructions of the cerebral blood vessels in volume conductor head modeling for EEG. To study the role of the highly arborized cerebral blood vessels, we created a submillimeter head model based on ultra-high-field-strength (7 T) structural MRI datasets. Blood vessels (arteries and emissary/intraosseous veins) were segmented using Frangi multi-scale vesselness filtering. The final head model consisted of a geometry-adapted cubic mesh with over 17 × 106 nodes. We solved the forward model using a finite-element-method (FEM) transfer matrix approach, which allowed reducing computation times substantially and quantified the importance of the blood vessel compartment by computing forward and inverse errors resulting from ignoring the blood vessels. Our results show that ignoring emissary veins piercing the skull leads to focal localization errors of approx. 5 to 15 mm. Large errors (>2 cm) were observed due to the carotid arteries and the dense arterial vasculature in areas such as in the insula or in the medial temporal lobe. Thus, in such predisposed areas, errors caused by neglecting blood vessels can reach similar magnitudes as those previously reported for neglecting white matter anisotropy, the CSF or the dura — structures which are generally considered important components of realistic EEG head models. Our findings thus imply that including a realistic blood vessel compartment in EEG head models will be helpful to

  17. The role of blood vessels in high-resolution volume conductor head modeling of EEG.

    PubMed

    Fiederer, L D J; Vorwerk, J; Lucka, F; Dannhauer, M; Yang, S; Dümpelmann, M; Schulze-Bonhage, A; Aertsen, A; Speck, O; Wolters, C H; Ball, T

    2016-03-01

    Reconstruction of the electrical sources of human EEG activity at high spatio-temporal accuracy is an important aim in neuroscience and neurological diagnostics. Over the last decades, numerous studies have demonstrated that realistic modeling of head anatomy improves the accuracy of source reconstruction of EEG signals. For example, including a cerebro-spinal fluid compartment and the anisotropy of white matter electrical conductivity were both shown to significantly reduce modeling errors. Here, we for the first time quantify the role of detailed reconstructions of the cerebral blood vessels in volume conductor head modeling for EEG. To study the role of the highly arborized cerebral blood vessels, we created a submillimeter head model based on ultra-high-field-strength (7T) structural MRI datasets. Blood vessels (arteries and emissary/intraosseous veins) were segmented using Frangi multi-scale vesselness filtering. The final head model consisted of a geometry-adapted cubic mesh with over 17×10(6) nodes. We solved the forward model using a finite-element-method (FEM) transfer matrix approach, which allowed reducing computation times substantially and quantified the importance of the blood vessel compartment by computing forward and inverse errors resulting from ignoring the blood vessels. Our results show that ignoring emissary veins piercing the skull leads to focal localization errors of approx. 5 to 15mm. Large errors (>2cm) were observed due to the carotid arteries and the dense arterial vasculature in areas such as in the insula or in the medial temporal lobe. Thus, in such predisposed areas, errors caused by neglecting blood vessels can reach similar magnitudes as those previously reported for neglecting white matter anisotropy, the CSF or the dura - structures which are generally considered important components of realistic EEG head models. Our findings thus imply that including a realistic blood vessel compartment in EEG head models will be helpful to

  18. A novel method for measuring hydraulic conductivity at the human blood-nerve barrier in vitro.

    PubMed

    Helton, E Scott; Palladino, Steven; Ubogu, Eroboghene E

    2017-01-01

    Microvascular barrier permeability to water is an essential biophysical property required for the homeostatic maintenance of unique tissue microenvironments. This is of particular importance in peripheral nerves where strict control of ionic concentrations is needed for axonal signal transduction. Previous studies have associated inflammation, trauma, toxin exposure and metabolic disease with increases in water influx and hydrostatic pressure in peripheral nerves with resultant endoneurial edema that may impair axonal function. The regulation of water permeability across endoneurial microvessels that form the blood-nerve barrier (BNB) is poorly understood. Variations exist in apparatus and methods used to measure hydraulic conductivity. The objective of the study was to develop a simplified hydraulic conductivity system using commercially available components to evaluate the BNB. We determined the mean hydraulic conductivity of cultured confluent primary and immortalized human endoneurial endothelial cell layers as 2.00×10(-7) and 2.17×10(-7)cm/s/cm H₂O respectively, consistent with restrictive microvascular endothelial cells in vitro. We also determined the mean hydraulic conductivity of immortalized human brain microvascular endothelial cell layers, a commonly used blood-brain barrier (BBB) cell line, as 0.20×10(-7)cm/s/cm H₂O, implying a mean 10-fold higher resistance to transendothelial water flux in the brain compared to peripheral nerves. To our knowledge, this is the first reported measurement of human BNB and BBB hydraulic conductivities. This model represents an important tool to further characterize the human BNB and deduce the molecular determinants and signaling mechanisms responsible for BNB hydraulic conductivity in normal and disease states in vitro.

  19. Effect of Photorefractive Keratectomy on Optic Nerve Head Topography and Retinal Nerve Fiber Layer Thickness Measured by Heidelberg Retina Tomograph 3

    PubMed Central

    Nilforushan, Naveed; Azadi, Pejvak; Soudi, Reza; Shaheen, Yahya; Sheibani, Kourosh

    2016-01-01

    Purpose: To determine whether photorefractive keratectomy (PRK) has a significant effect on optic nerve head (ONH) parameters and peripapillary retinal nerve fiber layer (RNFL) thickness measured by the Heidelberg Retina Tomograph 3 (Heidelberg Engineering GmbH, Heidelberg, Germany) in eyes with low to moderate myopia. Methods: This prospective, interventional case series, includes 43 consecutive myopic eyes which were assessed on the day of PRK and 3 months postoperatively using the HRT3. Among the stereometric parameters, we compared disc area, linear cup disc ratio, cup shape measure, global rim area, global rim volume, RNFL height variation contour and mean RNFL thickness; out of the Glaucoma Probability Score (GPS) we assessed changes in global value, rim steepness temporal/superior, and temporal/inferior, as well as cup size and cup depth before and after PRK. Results: Mean refractive error before and after PRK were −3.24 ± 1.31 and −0.20 ± 0.42 diopters, respectively. No significant change occurred in disc area, linear cup disc ratio, cup shape measure, rim area and rim volume among the stereometric parameters; and in rim steepness temporal/superior and rim steepness temporal/inferior in the GPS before and after PRK using the default average keratometry. However, RNFL height variation contour, mean RNFL thickness, and cup size and depth were significantly altered after PRK (P < 0.05). Conclusion: PRK can affect some HRT3 parameters. Although the most important stereometric parameters for differentiating normal, suspect or glaucomatous patients such as rim and cup measurements in stereometric parameters were not changed. PMID:27413492

  20. Spectral Domain Optical Coherence Tomography in Glaucoma: Qualitative and Quantitative Analysis of the Optic Nerve Head and Retinal Nerve Fiber Layer (An AOS Thesis)

    PubMed Central

    Chen, Teresa C.

    2009-01-01

    Purpose: To demonstrate that video-rate spectral domain optical coherence tomography (SDOCT) can qualitatively and quantitatively evaluate optic nerve head (ONH) and retinal nerve fiber layer (RNFL) glaucomatous structural changes. To correlate quantitative SDOCT parameters with disc photography and visual fields. Methods: SDOCT images from 4 glaucoma eyes (4 patients) with varying stages of open-angle glaucoma (ie, early, moderate, late) were qualitatively contrasted with 2 age-matched normal eyes (2 patients). Of 61 other consecutive patients recruited in an institutional setting, 53 eyes (33 patients) met inclusion/exclusion criteria for quantitative studies. Images were obtained using two experimental SDOCT systems, one utilizing a superluminescent diode and the other a titanium:sapphire laser source, with axial resolutions of about 6 μm and 3 μm, respectively. Results: Classic glaucomatous ONH and RNFL structural changes were seen in SDOCT images. An SDOCT reference plane 139 μm above the retinal pigment epithelium yielded cup-disc ratios that best correlated with masked physician disc photography cup-disc ratio assessments. The minimum distance band, a novel SDOCT neuroretinal rim parameter, showed good correlation with physician cup-disc ratio assessments, visual field mean deviation, and pattern standard deviation (P values range, .0003–.024). RNFL and retinal thickness maps correlated well with disc photography and visual field testing. Conclusions: To our knowledge, this thesis presents the first comprehensive qualitative and quantitative evaluation of SDOCT images of the ONH and RNFL in glaucoma. This pilot study provides basis for developing more automated quantitative SDOCT-specific glaucoma algorithms needed for future prospective multicenter national trials. PMID:20126502

  1. Blood-Sparing Techniques in Head and Neck Surgery.

    PubMed

    Rabinowitz, Mindy R; Cognetti, David M; Nyquist, Gurston G

    2016-06-01

    Given the risks and potential complications of allogenic blood transfusion (ABT), as well as the expanding population of patients for whom ABT may not be an option, it is important for the treating physician, anesthesiologist, and surgeon to be well-versed in various alternatives. A good grasp of the concepts discussed in this article will help to customize a treatment plan that is specific to each patient's underlying disease and personal preferences without compromising appropriate medical care.

  2. Blood pressure control with selective vagal nerve stimulation and minimal side effects

    NASA Astrophysics Data System (ADS)

    Plachta, Dennis T. T.; Gierthmuehlen, Mortimer; Cota, Oscar; Espinosa, Nayeli; Boeser, Fabian; Herrera, Taliana C.; Stieglitz, Thomas; Zentner, Joseph

    2014-06-01

    Objective. Hypertension is the largest threat to patient health and a burden to health care systems. Despite various options, 30% of patients do not respond sufficiently to medical treatment. Mechanoreceptors in the aortic arch relay blood pressure (BP) levels through vagal nerve (VN) fibers to the brainstem and trigger the baroreflex, lowering the BP. Selective electrical stimulation of these nerve fibers reduced BP in rats. However, there is no technique described to localize and stimulate these fibers inside the VN without inadvertent stimulation of non-baroreceptive fibers causing side effects like bradycardia and bradypnea. Approach. We present a novel method for selective VN stimulation to reduce BP without the aforementioned side effects. Baroreceptor compound activity of rat VN (n = 5) was localized using a multichannel cuff electrode, true tripolar recording and a coherent averaging algorithm triggered by BP or electrocardiogram. Main results. Tripolar stimulation over electrodes near the barofibers reduced the BP without triggering significant bradycardia and bradypnea. The BP drop was adjusted to 60% of the initial value by varying the stimulation pulse width and duration, and lasted up to five times longer than the stimulation. Significance. The presented method is robust to impedance changes, independent of the electrode's relative position, does not compromise the nerve and can run on implantable, ultra-low power signal processors.

  3. Human muscle nerve sympathetic activity at rest. Relationship to blood pressure and age

    PubMed Central

    Sundlöf, G.; Wallin, B. G.

    1978-01-01

    1. Recordings of multi-unit sympathetic activity were made from median or peroneal muscle nerve fascicles in thirty-three healthy subjects, resting in recumbent position. Simultaneous recordings of intra-arterial blood pressure were made in seventeen subjects. The neural activity, quantified by counting the number of pulse synchronous sympathetic bursts in the mean voltage neurogram (burst incidence), was plotted against the arterial blood pressure level and the age of the subjects. The effects of spontaneous temporary blood pressure fluctuations were studied by correlating different pressure parameters of individual heart beats to the probability of occurrence of a sympathetic burst and to the amplitude of the occurring burst. 2. Between different subjects there were marked differences in burst incidence, from less than 10 to more than 90 bursts/100 heart beats. No correlation was found to interindividual differences in the arterial blood pressure level but there was a slight tendency for increasing burst incidence with increasing age. 3. Irrespective of the magnitude of the burst incidence, the bursts always occurred more frequently during spontaneous transient blood pressure reductions than during transient increases in blood pressure. When, for each heart cycle, the occurrence of a sympathetic burst was correlated with different blood pressure parameters there was regularly a close negative correlation to diastolic pressure, a low correlation to systolic and an intermediary negative correlation to mean blood pressure. There was a positive correlation to pulse pressure and to pulse interval. 4. When measured for individual heart beats, not only the occurrence but also the mean voltage amplitude of the sympathetic bursts tended to increase with decreasing diastolic pressure. 5. In a given subject when comparing heart beats with the same diastolic pressure, the occurrence as well as the amplitude of the sympathetic bursts was higher for heart beats occurring

  4. Imaging blood vessels of the head and neck.

    PubMed Central

    Sellar, R J

    1995-01-01

    ATHEROSCLEROTIC DISEASE: Patients with transient ischaemic attacks or a non-disabling stroke who are surgical candidates should be screened with Doppler ultrasound, or MRA/CT, or both. The choice will depend on local expertise and availability. If DUS is used it is recommended that the equipment is regularly calibrated and a prospective audit of results, particularly of those patients that go on to angiography, is maintained locally. Those patients found to have the DUS equivalent of a 50% stenosis should have angiography only if surgical or balloon angioplasty treatment is contemplated. Angiography should be performed with meticulous technique to minimise risks. ANEURYSM AND ARTERIOVENOUS MALFORMATIONS: Angiography remains the investigation of choice for patients with subarachnoid haemorrhage. Magnetic resonance angiography and CT can demonstrate the larger aneurysm but because even small aneurysms can rupture with devastating effects, these techniques are not the examination of first choice. Angiography is also the only technique that adequately defines the neck of an aneurysm. This information is becoming increasingly important in management decisions-for instance, whether to clip or use a coil. Likewise angiography is the only technique to fully define the vascular anatomy of arteriovenous malformations although the size of the nidus can be monitored by MRA and this is a useful method of follow up after stereotactic radiosurgery, embolisation, or surgery. There are specific uses for MRA such as in patients presenting with a painful 3rd nerve palsy and as a screening test for those patients with a strong family history of aneurysms. VASCULITIS, FIBROMUSCULAR HYPERPLASIA, AND DISSECTION: These rare arterial diseases are best detected by angiography, although there are increasing reports of successful diagnosis by MRA. There are traps for the many unwary and MRA does not give an anatomical depiction of the arteries but a flow map. Slow flow may lead to signal loss

  5. Visualization of the 3-D topography of the optic nerve head through a passive stereo vision model

    NASA Astrophysics Data System (ADS)

    Ramirez, Juan M.; Mitra, Sunanda; Morales, Jose

    1999-01-01

    This paper describes a system for surface recovery and visualization of the 3D topography of the optic nerve head, as support of early diagnosis and follow up to glaucoma. In stereo vision, depth information is obtained from triangulation of corresponding points in a pair of stereo images. In this paper, the use of the cepstrum transformation as a disparity measurement technique between corresponding windows of different block sizes is described. This measurement process is embedded within a coarse-to-fine depth-from-stereo algorithm, providing an initial range map with the depth information encoded as gray levels. These sparse depth data are processed through a cubic B-spline interpolation technique in order to obtain a smoother representation. This methodology is being especially refined to be used with medical images for clinical evaluation of some eye diseases such as open angle glaucoma, and is currently under testing for clinical evaluation and analysis of reproducibility and accuracy.

  6. Jugular venous pooling during lowering of the head affects blood pressure of the anesthetized giraffe.

    PubMed

    Brøndum, E; Hasenkam, J M; Secher, N H; Bertelsen, M F; Grøndahl, C; Petersen, K K; Buhl, R; Aalkjaer, C; Baandrup, U; Nygaard, H; Smerup, M; Stegmann, F; Sloth, E; Ostergaard, K H; Nissen, P; Runge, M; Pitsillides, K; Wang, T

    2009-10-01

    How blood flow and pressure to the giraffe's brain are regulated when drinking remains debated. We measured simultaneous blood flow, pressure, and cross-sectional area in the carotid artery and jugular vein of five anesthetized and spontaneously breathing giraffes. The giraffes were suspended in the upright position so that we could lower the head. In the upright position, mean arterial pressure (MAP) was 193 +/- 11 mmHg (mean +/- SE), carotid flow was 0.7 +/- 0.2 l/min, and carotid cross-sectional area was 0.85 +/- 0.04 cm(2). Central venous pressure (CVP) was 4 +/- 2 mmHg, jugular flow was 0.7 +/- 0.2 l/min, and jugular cross-sectional area was 0.14 +/- 0.04 cm(2) (n = 4). Carotid arterial and jugular venous pressures at head level were 118 +/- 9 and -7 +/- 4 mmHg, respectively. When the head was lowered, MAP decreased to 131 +/- 13 mmHg, while carotid cross-sectional area and flow remained unchanged. Cardiac output was reduced by 30%, CVP decreased to -1 +/- 2 mmHg (P < 0.01), and jugular flow ceased as the jugular cross-sectional area increased to 3.2 +/- 0.6 cm(2) (P < 0.01), corresponding to accumulation of approximately 1.2 l of blood in the veins. When the head was raised, the jugular veins collapsed and blood was returned to the central circulation, and CVP and cardiac output were restored. The results demonstrate that in the upright-positioned, anesthetized giraffe cerebral blood flow is governed by arterial pressure without support of a siphon mechanism and that when the head is lowered, blood accumulates in the vein, affecting MAP.

  7. Cerebral blood velocity and other cardiovascular responses to 2 days of head-down tilt

    NASA Technical Reports Server (NTRS)

    Frey, Mary A. B.; Mader, Thomas H.; Bagian, James P.; Charles, John B.; Meehan, Richard T.

    1993-01-01

    Spaceflight induces a cephalad redistribution of fluid volume and blood flow within the human body, and space motion sickness, which is a problem during the first few days of space flight, could be related to these changes in fluid status and in blood flow of the cerebrum and vestibular system. To evaluate possible changes in cerebral blood flow during simulated weightlessness, we measured blood velocity in the middle cerebral artery (MCA) along with retinal vascular diameters, intraocular pressure, impedance cardiography, and sphygmomanometry on nine men (26.2 +/- 6.6 yr) morning and evening for 2 days during continuous 10 deg head-down tilt (HDT). When subjects went from seated to head-down bed rest, their heart rate and retinal diameters decreased, and intraocular pressures increased. After 48 h of HDT, blood flow velocity in the MCA was decreased and thoracic impedance was increased, indicating less fluid in the thorax. Percent changes in blood flow velocities in the MCA after 48 h of HDT were inversely correlated with percent changes in retinal vascular diameters. Blood flow velocities in the MCA were inversely correlated (intersubject) with arterial pressures and retinal vascular diameters. Heart rate, stroke volume, cardiac output, systolic arterial pressure, and at times pulse pressure and blood flow velocities in the MCA were greater in the evening. Total peripheral resistance was higher in the morning. Although cerebral blood velocity is reduced after subjects are head down for 2 days, the inverse relationship with retinal vessel diameters, which have control analogous to that of cerebral vessels, indicates cerebral blood flow is not reduced.

  8. The Connective Tissue Components of Optic Nerve Head Cupping in Monkey Experimental Glaucoma Part 1: Global Change

    PubMed Central

    Yang, Hongli; Ren, Ruojin; Lockwood, Howard; Williams, Galen; Libertiaux, Vincent; Downs, Crawford; Gardiner, Stuart K.; Burgoyne, Claude F.

    2015-01-01

    Purpose To characterize optic nerve head (ONH) connective tissue change within 21 monkey experimental glaucoma (EG) eyes, so as to identify its principal components. Methods Animals were imaged three to five times at baseline then every 2 weeks following chronic unilateral IOP elevation, and euthanized early through end-stage confocal scanning laser tomographic change. Optic nerve heads were serial-sectioned, three-dimensionally (3D) reconstructed, delineated, and quantified. Overall EG versus control eye differences were assessed by general estimating equations (GEE). Significant, animal-specific, EG eye change was required to exceed the maximum physiologic intereye differences in six healthy animals. Results Overall EG eye change was significant (P < 0.0026) and animal-specific EG eye change most frequent, for five phenomena (number of EG eyes and range of animal-specific change): posterior laminar deformation (21, −29 to −437 μm), laminar thickening (11, 20–73 μm) and thinning (3, −23 to −31 μm), scleral canal expansion (17, 20–139 μm), outward anterior (16, −16 to −124 μm) and posterior (17, −22 to −279 μm) laminar insertion migration, and peripapillary scleral bowing (11, 21–77 μm). Experimental glaucoma versus control eye laminar thickness differences were bimodal in behavior, being thickened in most EG eyes demonstrating the least deformation and less thickened or thinned in most EG eyes demonstrating the greatest deformation. Conclusions Our postmortem studies retrospectively identify five connective tissue components of ONH “cupping” in monkey EG which serve as targets for longitudinally staging and phenotyping ONH connective tissue alteration within all forms of monkey and human optic neuropathy. PMID:26641545

  9. The pathogenic role of transforming growth factor-β2 in glaucomatous damage to the optic nerve head.

    PubMed

    Fuchshofer, Rudolf

    2011-08-01

    In patients with primary open angle glaucoma (POAG), the optic nerve head (ONH) shows characteristic cupping correlated with visual field defects. The progressive optic neuropathy is characterized by irreversible loss of retinal ganglion cells (RGC). The critical risk factor for axonal damage at the ONH is an elevated intraocular pressure (IOP). The increase in IOP correlates with axonal loss in the ONH, which might be due to an impaired axoplasmatic flow leading to the loss of RGCs. Damage to the optic nerve is thought to occur in the lamina cribrosa (LC) region of the ONH, which is composed of characteristic sieve-like connective tissue cribriform plates through which RGC axons exit the eye. The cupping of the optic disc, and the compression and excavation of LC are characteristic signs of glaucomatous ONH remodelling. In ONH of POAG patients a disorganized distribution and deposition of elastic fibers and a typical pronounced thickening of the connective tissue septae surrounding the optic nerve fibers is found. Transforming growth factor (TGF)-β2 could be one of the pathogenic factors responsible for the structural alterations in POAG patients as the TGF-β2 levels in the ONH of glaucomatous eyes are elevated as well as in the aqueous homour. TGF-β2 leads to an increased synthesis of extracellular matrix (ECM) molecules mediated by connective tissue growth factor and to an impaired ECM degradation in cultured ONH astrocytes. Bone morphogenetic protein (BMP)-4 effectively antagonizes the effects of TGF-β2 on matrix deposition. The BMP antagonist gremlin blocks this inhibition, allowing TGF-β2 stimulation of ECM synthesis. Overall, the ECM in the ONH is kept in balance in the OHN by factors that augment or block the activity of TGF-β2.

  10. A joint estimation detection of Glaucoma progression in 3D spectral domain optical coherence tomography optic nerve head images

    PubMed Central

    Belghith, Akram; Bowd, Christopher; Weinreb, Robert N.; Zangwill, Linda M.

    2014-01-01

    Glaucoma is an ocular disease characterized by distinctive changes in the optic nerve head (ONH) and visual field. Glaucoma can strike without symptoms and causes blindness if it remains without treatment. Therefore, early disease detection is important so that treatment can be initiated and blindness prevented. In this context, important advances in technology for non-invasive imaging of the eye have been made providing quantitative tools to measure structural changes in ONH topography, an essential element for glaucoma detection and monitoring. 3D spectral domain optical coherence tomography (SD-OCT), an optical imaging technique, has been commonly used to discriminate glaucomatous from healthy subjects. In this paper, we present a new framework for detection of glaucoma progression using 3D SD-OCT images. In contrast to previous works that the retinal nerve fiber layer (RNFL) thickness measurement provided by commercially available spectral-domain optical coherence tomograph, we consider the whole 3D volume for change detection. To integrate a priori knowledge and in particular the spatial voxel dependency in the change detection map, we propose the use of the Markov Random Field to handle a such dependency. To accommodate the presence of false positive detection, the estimated change detection map is then used to classify a 3D SDOCT image into the “non-progressing” and “progressing” glaucoma classes, based on a fuzzy logic classifier. We compared the diagnostic performance of the proposed framework to existing methods of progression detection. PMID:25606299

  11. A joint estimation detection of Glaucoma progression in 3D spectral domain optical coherence tomography optic nerve head images

    NASA Astrophysics Data System (ADS)

    Belghith, Akram; Bowd, Christopher; Weinreb, Robert N.; Zangwill, Linda M.

    2014-03-01

    Glaucoma is an ocular disease characterized by distinctive changes in the optic nerve head (ONH) and visual field. Glaucoma can strike without symptoms and causes blindness if it remains without treatment. Therefore, early disease detection is important so that treatment can be initiated and blindness prevented. In this context, important advances in technology for non-invasive imaging of the eye have been made providing quantitative tools to measure structural changes in ONH topography, an essential element for glaucoma detection and monitoring. 3D spectral domain optical coherence tomography (SD-OCT), an optical imaging technique, has been commonly used to discriminate glaucomatous from healthy subjects. In this paper, we present a new framework for detection of glaucoma progression using 3D SD-OCT images. In contrast to previous works that the retinal nerve fiber layer (RNFL) thickness measurement provided by commercially available spectral-domain optical coherence tomograph, we consider the whole 3D volume for change detection. To integrate a priori knowledge and in particular the spatial voxel dependency in the change detection map, we propose the use of the Markov Random Field to handle a such dependency. To accommodate the presence of false positive detection, the estimated change detection map is then used to classify a 3D SDOCT image into the "non-progressing" and "progressing" glaucoma classes, based on a fuzzy logic classifier. We compared the diagnostic performance of the proposed framework to existing methods of progression detection.

  12. Experimental Glaucoma Causes Optic Nerve Head Neural Rim Tissue Compression: A Potentially Important Mechanism of Axon Injury

    PubMed Central

    Fortune, Brad; Reynaud, Juan; Hardin, Christy; Wang, Lin; Sigal, Ian A.; Burgoyne, Claude F.

    2016-01-01

    Purpose We tested the hypothesis that experimental glaucoma (EG) results in greater thinning of the optic nerve head (ONH) neural rim tissue than the peripapillary retinal nerve fiber layer (RNFL) tissue. Methods Longitudinal spectral-domain optical coherence tomography (SDOCT) imaging of the ONH and peripapillary RNFL was performed every other week under manometric IOP control (10 mm Hg) in 51 nonhuman primates (NHP) during baseline and after induction of unilateral EG. The ONH parameter minimum rim area (MRA) was derived from 80 radial B-scans centered on the ONH; RNFL cross-sectional area (RNFLA) from a peripapillary circular B-scan with 12° diameter. Results In control eyes, MRA was 1.00 ± 0.19 mm2 at baseline and 1.00 ± 0.19 mm2 at the final session (P = 0.77), while RNFLA was 0.95 ± 0.09 and 0.95 ± 0.10 mm2, respectively (P = 0.96). In EG eyes, MRA decreased from 1.00 ± 0.19 mm2 at baseline to 0.63 ± 0.21 mm2 at the final session (P < 0.0001), while RNFLA decreased from 0.95 ± 0.09 to 0.74 ± 0.19 mm2, respectively (P < 0.0001). Thus, MRA decreased by 36.4 ± 20.6% in EG eyes, significantly more than the decrease in RNFLA (21.7 ± 19.4%, P < 0.0001). Other significant changes in EG eyes included increased Bruch's membrane opening (BMO) nonplanarity (P < 0.05), decreased BMO aspect ratio (P < 0.0001), and decreased MRA angle (P < 0.001). Bruch's membrane opening area did not change from baseline in either control or EG eyes (P = 0.27, P = 0.15, respectively). Conclusions Optic nerve head neural rim tissue thinning exceeded peripapillary RNFL thinning in NHP EG. These results support the hypothesis that axon bundles are compressed transversely within the ONH rim along with glaucomatous deformation of connective tissues. PMID:27564522

  13. Human umbilical cord blood stem cells and brain-derived neurotrophic factor for optic nerve injury: a biomechanical evaluation

    PubMed Central

    Zhang, Zhong-jun; Li, Ya-jun; Liu, Xiao-guang; Huang, Feng-xiao; Liu, Tie-jun; Jiang, Dong-mei; Lv, Xue-man; Luo, Min

    2015-01-01

    Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 106 human umbilical cord blood stem cells. After 30 days, the maximum load, maximum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neurotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These findings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, improve biomechanical properties, and contribute to the recovery after injury. PMID:26330839

  14. Influence of long-term head-down body position on innervation density in extremity blood vessels

    NASA Technical Reports Server (NTRS)

    Lorant, M.; Raffai, G.; Nadasy, G.; Feher, E.; Monos, E.

    2001-01-01

    The aim of the present study was to quantitate and compare the density of nerve terminals (NTD), as well as of their synaptic vesicle population (SyVD) in saphenous and brachial vein and artery, obtained from rats maintained in the horizontal or head-down tilted (HDT) position for two weeks. The same technique was applied as that for the head-up tilt study.

  15. Eppur Si Muove: The dynamic nature of physiological control of renal blood flow by the renal sympathetic nerves.

    PubMed

    Schiller, Alicia M; Pellegrino, Peter Ricci; Zucker, Irving H

    2017-05-01

    Tubuloglomerular feedback and the myogenic response are widely appreciated as important regulators of renal blood flow, but the role of the sympathetic nervous system in physiological renal blood flow control remains controversial. Where classic studies using static measures of renal blood flow failed, dynamic approaches have succeeded in demonstrating sympathetic control of renal blood flow under normal physiological conditions. This review focuses on transfer function analysis of renal pressure-flow, which leverages the physical relationship between blood pressure and flow to assess the underlying vascular control mechanisms. Studies using this approach indicate that the renal nerves are important in the rapid regulation of the renal vasculature. Animals with intact renal innervation show a sympathetic signature in the frequency range associated with sympathetic vasomotion that is eliminated by renal denervation. In conscious rabbits, this sympathetic signature exerts vasoconstrictive, baroreflex control of renal vascular conductance, matching well with the rhythmic, baroreflex-influenced control of renal sympathetic nerve activity and complementing findings from other studies employing dynamic approaches to study renal sympathetic vascular control. In this light, classic studies reporting that nerve stimulation and renal denervation do not affect static measures of renal blood flow provide evidence for the strength of renal autoregulation rather than evidence against physiological renal sympathetic control of renal blood flow. Thus, alongside tubuloglomerular feedback and the myogenic response, renal sympathetic outflow should be considered an important physiological regulator of renal blood flow. Clinically, renal sympathetic vasomotion may be important for solving the problems facing the field of therapeutic renal denervation.

  16. Sox10 Expression in Goldfish Retina and Optic Nerve Head in Controls and after the Application of Two Different Lesion Paradigms

    PubMed Central

    Parrilla, Marta; León-Lobera, Fernando; Lillo, Concepción; Arévalo, Rosario; Aijón, José; Lara, Juan Manuel; Velasco, Almudena

    2016-01-01

    The mammalian central nervous system (CNS) is unable to regenerate. In contrast, the CNS of fish, including the visual system, is able to regenerate after damage. Moreover, the fish visual system grows continuously throughout the life of the animal, and it is therefore an excellent model to analyze processes of myelination and re-myelination after an injury. Here we analyze Sox10+ oligodendrocytes in the goldfish retina and optic nerve in controls and after two kinds of injuries: cryolesion of the peripheral growing zone and crushing of the optic nerve. We also analyze changes in a major component of myelin, myelin basic protein (MBP), as a marker for myelinated axons. Our results show that Sox10+ oligodendrocytes are located in the retinal nerve fiber layer and along the whole length of the optic nerve. MBP was found to occupy a similar location, although its loose appearance in the retina differed from the highly organized MBP+ axon bundles in the optic nerve. After optic nerve crushing, the number of Sox10+ cells decreased in the crushed area and in the optic nerve head. Consistent with this, myelination was highly reduced in both areas. In contrast, after cryolesion we did not find changes in the Sox10+ population, although we did detect some MBP- degenerating areas. We show that these modifications in Sox10+ oligodendrocytes are consistent with their role in oligodendrocyte identity, maintenance and survival, and we propose the optic nerve head as an excellent area for research aimed at better understanding of de- and remyelination processes. PMID:27149509

  17. Sox10 Expression in Goldfish Retina and Optic Nerve Head in Controls and after the Application of Two Different Lesion Paradigms.

    PubMed

    Parrilla, Marta; León-Lobera, Fernando; Lillo, Concepción; Arévalo, Rosario; Aijón, José; Lara, Juan Manuel; Velasco, Almudena

    2016-01-01

    The mammalian central nervous system (CNS) is unable to regenerate. In contrast, the CNS of fish, including the visual system, is able to regenerate after damage. Moreover, the fish visual system grows continuously throughout the life of the animal, and it is therefore an excellent model to analyze processes of myelination and re-myelination after an injury. Here we analyze Sox10+ oligodendrocytes in the goldfish retina and optic nerve in controls and after two kinds of injuries: cryolesion of the peripheral growing zone and crushing of the optic nerve. We also analyze changes in a major component of myelin, myelin basic protein (MBP), as a marker for myelinated axons. Our results show that Sox10+ oligodendrocytes are located in the retinal nerve fiber layer and along the whole length of the optic nerve. MBP was found to occupy a similar location, although its loose appearance in the retina differed from the highly organized MBP+ axon bundles in the optic nerve. After optic nerve crushing, the number of Sox10+ cells decreased in the crushed area and in the optic nerve head. Consistent with this, myelination was highly reduced in both areas. In contrast, after cryolesion we did not find changes in the Sox10+ population, although we did detect some MBP- degenerating areas. We show that these modifications in Sox10+ oligodendrocytes are consistent with their role in oligodendrocyte identity, maintenance and survival, and we propose the optic nerve head as an excellent area for research aimed at better understanding of de- and remyelination processes.

  18. Three-dimensional interactive and stereotactic atlas of head muscles and glands correlated with cranial nerves and surface and sectional neuroanatomy.

    PubMed

    Nowinski, Wieslaw L; Chua, Beng Choon; Johnson, Aleksandra; Qian, Guoyu; Poh, Lan Eng; Yi, Su Hnin Wut; Bivi, Aminah; Nowinska, Natalia G

    2013-04-30

    Three-dimensional (3D) relationships between head muscles and cranial nerves innervating them are complicated. Existing sources present these relationships in illustrations, radiologic scans, or autopsy photographs, which are limited for learning and use. Developed electronic atlases are limited in content, quality, functionality, and/or presentation. We create a truly 3D interactive, stereotactic and high quality atlas, which provides spatial relationships among head muscles, glands and cranial nerves, and correlates them to surface and sectional neuroanatomy. The head muscles and glands were created from a 3T scan by contouring them and generating 3D models. They were named and structured according to Terminologia anatomica. The muscles were divided into: extra-ocular, facial, masticatory and other muscles, and glands into mouth and other glands. The muscles, glands (and also head) were placed in a stereotactic coordinate system. This content was integrated with cranial nerves and neuroanatomy created earlier. To explore this complex content, a scalable user interface was designed with 12 modules including central nervous system (cerebrum, cerebellum, brainstem, spinal cord), cranial nerves, muscles, glands, arterial system, venous system, tracts, deep gray nuclei, ventricles, white matter, visual system, head. Anatomy exploration operations include compositing/decompositing, individual/group selection, 3D view-index mapping, 3D labeling, highlighting, distance measuring, 3D brain cutting, and axial/coronal/sagittal triplanar display. To our best knowledge, this is the first truly 3D, stereotactic, interactive, fairly complete atlas of head muscles, and the first attempt to create a 3D stereotactic atlas of glands. Its use ranges from education of students and patients to research to potential clinical applications.

  19. Renal nerves dynamically regulate renal blood flow in conscious, healthy rabbits.

    PubMed

    Schiller, Alicia M; Pellegrino, Peter R; Zucker, Irving H

    2016-01-15

    Despite significant clinical interest in renal denervation as a therapy, the role of the renal nerves in the physiological regulation of renal blood flow (RBF) remains debated. We hypothesized that the renal nerves physiologically regulate beat-to-beat RBF variability (RBFV). This was tested in chronically instrumented, healthy rabbits that underwent either bilateral surgical renal denervation (DDNx) or a sham denervation procedure (INV). Artifact-free segments of RBF and arterial pressure (AP) from calmly resting, conscious rabbits were used to extract RBFV and AP variability for time-domain, frequency-domain, and nonlinear analysis. Whereas steady-state measures of RBF, AP, and heart rate did not statistically differ between groups, DDNx rabbits had greater RBFV than INV rabbits. AP-RBF transfer function analysis showed greater admittance gain in DDNx rabbits than in INV rabbits, particularly in the low-frequency (LF) range where systemic sympathetic vasomotion gives rise to AP oscillations. In the LF range, INV rabbits exhibited a negative AP-RBF phase shift and low coherence, consistent with the presence of an active control system. Neither of these features were present in the LF range of DDNx rabbits, which showed no phase shift and high coherence, consistent with a passive, Ohm's law pressure-flow relationship. Renal denervation did not significantly affect nonlinear RBFV measures of chaos, self-affinity, or complexity, nor did it significantly affect glomerular filtration rate or extracellular fluid volume. Cumulatively, these data suggest that the renal nerves mediate LF renal sympathetic vasomotion, which buffers RBF from LF AP oscillations in conscious, healthy rabbits.

  20. Tissue engineering with peripheral blood-derived mesenchymal stem cells promotes the regeneration of injured peripheral nerves.

    PubMed

    Pan, Mengjie; Wang, Xianghai; Chen, Yijing; Cao, Shangtao; Wen, Jinkun; Wu, Guofeng; Li, Yuanyuan; Li, Lixia; Qian, Changhui; Qin, Zhenqi; Li, Zhenlin; Tan, Dandan; Fan, Zhihao; Wu, Wutian; Guo, Jiasong

    2017-03-07

    Peripheral nerve injury repair can be enhanced by Schwann cell (SC) transplantation, but clinical applications are limited by the lack of a cell source. Thus, alternative systems for generating SCs are desired. Herein, we found the peripheral blood-derived mesenchymal stem cells (PBMSCs) could be induced into SC like cells with expressing SC-specific markers (S100, P75NTR and CNPase) and functional factors (NGF, NT-3, c-Fos, and Krox20). When the induced PBMSCs (iPBMSCs) were transplanted into crushed rat sciatic nerves, they functioned as SCs by wrapping the injured axons and expressing myelin specific marker of MBP. Furthermore, iPBMSCs seeded in an artificial nerve conduit to bridge a 10-mm defect in a sciatic nerve achieved significant nerve regeneration outcomes, including axonal regeneration and remyelination, nerve conduction recovery, and restoration of motor function, and attenuated myoatrophy and neuromuscular junction degeneration in the target muscle. Overall, the data from this study indicated that PBMSCs can transdifferentiate towards SC-like cells and have potential as grafting cells for nerve tissue engineering.

  1. Pseudocatalytic scavenging of the nerve agent VX with human blood components and the oximes obidoxime and HI-6.

    PubMed

    Wille, Timo; von der Wellen, Jens; Thiermann, Horst; Worek, Franz

    2017-03-01

    Despite six decades of extensive research in medical countermeasures against nerve agent poisoning, a broad spectrum acetylcholinesterase (AChE) reactivator is not yet available. One current approach is directed toward synthesizing oximes with high affinity and reactivatability toward butyrylcholinesterase (BChE) in plasma to generate an effective pseudocatalytic scavenger. An interim solution could be the administration of external AChE or BChE from blood products to augment pseudocatalytic scavenging with slower but clinically approved oximes to decrease nerve agent concentrations in the body. We here semiquantitatively investigate the ability of obidoxime and HI-6 to decrease the inhibitory activity of VX with human AChE and BChE from whole blood, erythrocyte membranes, erythrocytes, plasma, clinically available fresh frozen plasma and packed red blood cells. The main findings are that whole blood showed a VX concentration-dependent decrease in inhibitory activity with HI-6 being more potent than obidoxime. Using erythrocytes and erythrocyte membranes again, HI-6 was more potent compared to obidoxime. With freshly prepared plasma, obidoxime and HI-6 showed comparable results for the decrease in VX. The use of the clinically available blood products revealed that packed red blood cells showed similar kinetics as fresh erythrocytes. Fresh frozen plasma resulted in a slower and incomplete decrease in inhibitory plasma compared to freshly prepared plasma. In conclusion, the administration of blood products in combination with available oximes augments pseudocatalytic scavenging and might be useful to decrease the body load of persistent, highly toxic nerve agents.

  2. Confocal scanning laser tomography of the optic nerve head on the patients with Alzheimer's disease compared to glaucoma and control.

    PubMed

    Kurna, Sevda Aydin; Akar, Gokcen; Altun, Ahmet; Agirman, Yasemin; Gozke, Eren; Sengor, Tomris

    2014-12-01

    The purpose of this study was to evaluate optic nerve head (ONH) differences of the patients with Alzheimer's disease (AD) measured by confocal scanning laser tomography [Heidelberg Retina Tomograph (HRT) III] and compare with glaucoma and control subjects. Eighty-four patients were enrolled into the study: 44 eyes of 24 patients with mild to moderate AD (Group 1), 68 eyes of 35 patients with glaucoma (Group 2), and 49 eyes of 25 heathy volunteers as a control (Group 3). A complete ophthalmologic examination as well as a confocal scanning laser ophthalmoscopic assessment with HRT III were performed on all patients. Mean values of the ONH topographic parameters such as rim area (RA), rim volume (RV), height variation contour, linear cup/disc ratio, cup shape measure, and retinal nerve fiber layer (RNFL) were recorded. Mean values of RNFL thickness was 0.23 ± 0.07 in AD, 0.22 ± 0.09 in glaucoma and 0.24 ± 0.07 in the control group (p = 0.323). RA and RV were significantly lower, and linear C/D ratio was significantly higher in the glaucoma group when compared to AD and control (p < 0.05). There was no statistically significant difference between AD and control for the optic disc parameters tested (p > 0.05). We observed a negative correlation of the age with RNFL in all of the groups (p < 0.005). Age was the most important parameter affecting RNFL. Our results suggest that HRT does not demonstrate ONH differences between AD and control group, while it successfully differentiates glaucoma from AD and control cases of older age.

  3. Optic Nerve Head Parameters in a Turkish Population Over Forty Years of Age

    PubMed Central

    Niyaz, Leyla; Yıldırım, Nilgün; Musmul, Ahmet

    2016-01-01

    Objectives: To evaluate the optic disc area and cup area in a normal population over 40 years of age. Materials and Methods: This prospective study was performed in Eskişehir. Fundus photographs were obtained using a nonmydriatic fundus camera. Planimetric measurements of the optic disc and cup area were performed with VK-2 digital imaging software. Optic nerve parameters were then compared between sex and age groups. Results: A total of 3,038 subjects were evaluated. Mean age was 56.6±10.4 years (range 40-91 years). The median disc area of the subjects was 2.87 (2.53-3.23) mm2 in the right eyes and 2.89 (2.55-3.25) mm2 in the left eyes (p<0.001). The median cup area of the subjects was 0.46 mm2 (0.33-0.64 mm2) in the right eyes and 0.44 mm2 (0.33-0.61 mm2) in the left eyes (p<0.001). The differences in disc and cup area between male and female subjects were not statistically significant (p>0.05). Conclusion: We report the normal distribution of disc area and cup area measurements and their association with age and sex. PMID:28058153

  4. Electrical Stimulation of the Ear, Head, Cranial Nerve, or Cortex for the Treatment of Tinnitus: A Scoping Review

    PubMed Central

    Adjamian, Peyman

    2016-01-01

    Tinnitus is defined as the perception of sound in the absence of an external source. It is often associated with hearing loss and is thought to result from abnormal neural activity at some point or points in the auditory pathway, which is incorrectly interpreted by the brain as an actual sound. Neurostimulation therapies therefore, which interfere on some level with that abnormal activity, are a logical approach to treatment. For tinnitus, where the pathological neuronal activity might be associated with auditory and other areas of the brain, interventions using electromagnetic, electrical, or acoustic stimuli separately, or paired electrical and acoustic stimuli, have been proposed as treatments. Neurostimulation therapies should modulate neural activity to deliver a permanent reduction in tinnitus percept by driving the neuroplastic changes necessary to interrupt abnormal levels of oscillatory cortical activity and restore typical levels of activity. This change in activity should alter or interrupt the tinnitus percept (reduction or extinction) making it less bothersome. Here we review developments in therapies involving electrical stimulation of the ear, head, cranial nerve, or cortex in the treatment of tinnitus which demonstrably, or are hypothesised to, interrupt pathological neuronal activity in the cortex associated with tinnitus. PMID:27403346

  5. Automated discovery of structural features of the optic nerve head on the basis of image and genetic data

    NASA Astrophysics Data System (ADS)

    Christopher, Mark; Tang, Li; Fingert, John H.; Scheetz, Todd E.; Abramoff, Michael D.

    2014-03-01

    Evaluation of optic nerve head (ONH) structure is a commonly used clinical technique for both diagnosis and monitoring of glaucoma. Glaucoma is associated with characteristic changes in the structure of the ONH. We present a method for computationally identifying ONH structural features using both imaging and genetic data from a large cohort of participants at risk for primary open angle glaucoma (POAG). Using 1054 participants from the Ocular Hypertension Treatment Study, ONH structure was measured by application of a stereo correspondence algorithm to stereo fundus images. In addition, the genotypes of several known POAG genetic risk factors were considered for each participant. ONH structural features were discovered using both a principal component analysis approach to identify the major modes of variance within structural measurements and a linear discriminant analysis approach to capture the relationship between genetic risk factors and ONH structure. The identified ONH structural features were evaluated based on the strength of their associations with genotype and development of POAG by the end of the OHTS study. ONH structural features with strong associations with genotype were identified for each of the genetic loci considered. Several identified ONH structural features were significantly associated (p < 0.05) with the development of POAG after Bonferroni correction. Further, incorporation of genetic risk status was found to substantially increase performance of early POAG prediction. These results suggest incorporating both imaging and genetic data into ONH structural modeling significantly improves the ability to explain POAG-related changes to ONH structure.

  6. Quantitative analysis of three-dimensional fibrillar collagen microstructure within the normal, aged and glaucomatous human optic nerve head

    PubMed Central

    Jones, H. J.; Girard, M. J.; White, N.; Fautsch, M. P.; Morgan, J. E.; Ethier, C. R.; Albon, J.

    2015-01-01

    The aim of this study was to quantify connective tissue fibre orientation and alignment in young, old and glaucomatous human optic nerve heads (ONH) to understand ONH microstructure and predisposition to glaucomatous optic neuropathy. Transverse (seven healthy, three glaucomatous) and longitudinal (14 healthy) human ONH cryosections were imaged by both second harmonic generation microscopy and small angle light scattering (SALS) in order to quantify preferred fibre orientation (PFO) and degree of fibre alignment (DOFA). DOFA was highest within the peripapillary sclera (ppsclera), with relatively low values in the lamina cribrosa (LC). Elderly ppsclera DOFA was higher than that in young ppsclera (p < 0.00007), and generally higher than in glaucoma ppsclera. In all LCs, a majority of fibres had preferential orientation horizontally across the nasal–temporal axis. In all glaucomatous LCs, PFO was significantly different from controls in a minimum of seven out of 12 LC regions (p < 0.05). Additionally, higher fibre alignment was observed in the glaucomatous inferior–temporal LC (p < 0.017). The differences between young and elderly ONH fibre alignment within regions suggest that age-related microstructural changes occur within the structure. The additional differences in fibre alignment observed within the glaucomatous LC may reflect an inherent susceptibility to glaucomatous optic neuropathy, or may be a consequence of ONH remodelling and/or collapse. PMID:25808336

  7. Optic Nerve Head (ONH) Topographic Analysis by Stratus OCT in Normal Subjects: Correlation to Disc Size, Age, and Ethnicity

    PubMed Central

    Marsh, Barbara C.; Cantor, Louis B.; WuDunn, Darrell; Hoop, Joni; Lipyanik, Jennifer; Patella, Vincent Michael; Budenz, Donald L.; Greenfield, David S.; Savell, Jonathan; Schuman, Joel S.; Varma, Rohit

    2012-01-01

    Purpose To study optic nerve head (ONH) topography parameters measured by Stratus optical coherence tomography (OCT) in normal subjects and to analyze ONH data for differences in relation to disc size, ethnicity, and age. Methods Three hundred sixty-seven normal subjects underwent Stratus optical coherence tomography ONH measurement using the fast optic disc scan protocol software package 3.0. Only ONH scans meeting specific qualification criteria were included for data analysis ensuring appropriate scan quality and reliability. ONH topographic parameters of qualified scans were analyzed for differences in regards to optic disc size, age, and ethnicity. Results Two hundred and twelve qualified ONH scans were included for data analysis. Mean disc area was 2.27±0.41 mm2 and optic cup area, rim area, and horizontal integrated rim width increased with disc size, whereas vertical integrated rim area did not. Vertical integrated rim area, horizontal integrated rim width, and rim area decreased and cup area increased with age. Mean optic disc area was larger in African-Americans as compared with Hispanics or Whites and this difference was statistically significant. Conclusions Optic cup area, rim area, and horizontal integrated rim width correlated to disc size. Vertical integrated rim area, horizontal integrated rim width, rim area, and cup area, changed with age. African-American optic discs had larger disc area measurements as compared with Whites optic discs and this difference was statistically significant. PMID:19855299

  8. Complex conjugate artifact-free adaptive optics optical coherence tomography of in vivo human optic nerve head.

    PubMed

    Kim, Dae Yu; Werner, John S; Zawadzki, Robert J

    2012-12-01

    We acquired in vivo images of the human optic nerve head (ONH) using an adaptive optics-optical coherence tomography (AO-OCT) system. In order to improve imaging of the lamina cribrosa in the ONH with high lateral resolution and sensitivity, we implemented a complex conjugate artifact-free Fourier domain OCT (Fd-OCT) acquisition scheme with a reference arm-based phase shifting method. This allowed positioning of the lamina cribrosa structures near the zero path length difference where AO-OCT imaging achieves highest sensitivity. Implementation of our complex conjugate artifact removal (CCR) method required constant phase shifts between consecutive axial scans (A-scans), generated by continuous beam path-length changes from offsetting the pivot point of the scanning mirror placed in the reference arm. Fourier transform along the transverse axis and a filtering algorithm allowed reconstruction of CCR AO-OCT images. The suppression ratio of the mirror artifact was approximately 22 dB (at 18,000 A-scans per second acquisition speed) with a paperboard test target and an optimum phase-shift value. Finally, we reconstructed the three-dimensional structure of human ONH with enhanced depth range and sensitivity using CCR AO-OCT.

  9. Topographic anatomy of the external branch of the superior laryngeal nerve. Its importance in head and neck surgery.

    PubMed

    Kambic, V; Zargi, M; Radsel, Z

    1984-11-01

    The authors have studied the anatomy of the external branch of the superior laryngeal nerve in its entirety on 40 fresh cadavers, and they have drawn the following conclusions: the nerve ramifies from the vagus immediately below the nodose ganglion or in the ganglion itself. The nerve splits into two branches approximately 1.5 cm below the ganglion nodosum. In four cases, both branches originated from the vagus itself. In one case, anastomosis of the external branch of the superior laryngeal nerve with the recurrent nerve was found. The external branch of the superior laryngeal nerve is not usually severed at supraglottic laryngectomy but the nerve is at risk during neck dissections, resection of Zenker's diverticula and thyroidectomy. An accurate knowledge of its course should reduce the incidence of injury to the branches of the superior laryngeal nerve during surgery.

  10. Influence of two anesthetic techniques on blood sugar level in head injury patients: A comparative study

    PubMed Central

    Kumar, Manoj; Tripathi, Manoj; Malviya, Deepak; Malviya, P. S.; Kumar, Virendra; Tyagi, Amit

    2016-01-01

    Background: Head injury presents a major worldwide social, economic, and health problem. Hyperglycemia is a significant indicator of the severity of injury and predictor of outcome, which can easily be prevented. There has been a long-standing controversy regarding the use of inhalational or intravenous (i.v.) anesthetic agents for surgery of head injury cases and impact of these agents on blood sugar level. Aims and Objectives: The aim of this study is to find out anesthetic drugs and technique having minimal or no effect on the blood sugar, and Glasgow Coma Scale (GCS) of patients with a head injury by comparing two types of anesthetic techniques in surgery of head injury patients. Materials and Methods: This was a prospective, randomized, and comparative study, conducted on 60 adult head injury patients. The patients were divided into two groups of 30 each. Group I patients received induction with sevoflurane and then had O2 + air + sevoflurane for maintenance with controlled ventilation. Group II patients received induction with i.v. propofol and then had O2 + air + propofol for maintenance with controlled ventilation. Injection fentanyl was used in both the groups at the time of induction and in intermittent boluses in maintenance. In observation, blood sugar level and mean arterial pressure were assessed at different time periods perioperatively in both groups while GCS was analyzed pre- and post-operatively. Statistical Analysis: Statistical analysis was performed by Microsoft Excel 2010 using t-test for comparison between the two groups and Z-test for comparison of proportions. Results and Conclusion: Blood sugar level was found significantly higher in patients of sevoflurane group at 30 min after induction, at the end of surgery, and 1 h after the end of anesthesia than propofol group patients. This increase of blood sugar level did not have any significant alteration in the GCS profile of the patients in sevoflurane group as compared to propofol group

  11. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult louse ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to ...

  12. The promotion of endothelial progenitor cells recruitment by nerve growth factors in tissue-engineered blood vessels.

    PubMed

    Zeng, Wen; Yuan, Wei; Li, Li; Mi, Jianhong; Xu, Shangcheng; Wen, Can; Zhou, Zhenhua; Xiong, Jiaqiang; Sun, Jiansen; Ying, Dajun; Yang, Mingcan; Li, Xiaosong; Zhu, Chuhong

    2010-03-01

    Endothelial progenitor cells (EPCs) mobilization and homing are critical to the development of an anti-thrombosis and anti-stenosis tissue-engineered blood vessel. The growth and activation of blood vessels are supported by nerves. We investigated whether nerve growth factors (NGF) can promote EPCs mobilization and endothelialization of tissue-engineered blood vessels. In vitro, NGF promoted EPCs to form more colonies, stimulated human EPCs to differentiate into endothelial cells, and significantly enhanced EPCs migration. Flow cytometric analysis revealed that NGF treatment increased the number of EPCs in the peripheral circulation of C57BL/6 mice. Furthermore, the treatment of human EPCs with NGF facilitated their homing into wire-injured carotid arteries after injection into mice. Decellularized rat blood vessel matrix was incubated with EDC cross-linked collagen and bound to NGF protein using the bifunctional coupling agent N-succinmidyl3-(2-pyridyldit-hio) propionate (SPDP). The NGF-bound tissue-engineered blood vessel was implanted into rat carotid artery for 1 week and 1 month. NGF-bound blood vessels possessed significantly higher levels of endothelialization and patency than controls did. These results demonstrated that NGF can markedly increase EPCs mobilization and homing to vascular grafts. Neurotrophic factors such as NGF have a therapeutic potential for the construction of tissue-engineered blood vessels in vivo.

  13. Persistent effects after trigeminal nerve proprioceptive stimulation by mandibular extension on rat blood pressure, heart rate and pial microcirculation.

    PubMed

    Lapi, D; Colantuoni, A; Del Seppia, C; Ghione, S; Tonlorenzi, D; Brunelli, M; Scuri, R

    2013-03-01

    The trigemino-cardiac reflex is a brainstem reflex known to lead to a decrement in heart rate and blood pressure, whereas few data have been collected about its effects on the cerebral hemodynamic. In this study we assess the in vivo effects of trigeminal nerve peripheral stimulation by mandibular extension on pial microcirculation and systemic arterial blood pressure in rats. Experiments were performed in male Wistar rats subjected to mandibular extension obtained inserting an ad hoc developed retractor between the dental arches. Mean arterial blood pressure and heart rate were recorded and the pial arterioles were visualized by fluorescence microscopy to measure the vessel diameters before (15 minutes) during (5-15 minutes) and after (80 minutes) mandibular extension. While in control rats (sham-operated rats) and in rats subjected to the dissection of the trigeminal peripheral branches mean arterial blood pressure, heart rate and pial microcirculation did not change during the whole observation period (110 minutes), in rats submitted to mandibular extension, mean arterial blood pressure, heart rate and arteriolar diameter significantly decreased during stimulation. Afterward mean arterial blood pressure remained reduced as well as heart rate, while arteriolar diameter significantly increased evidencing a vasodilatation persisting for the whole remaining observation time. Therefore, trigeminal nerve proprioceptive stimulation appears to trigger specific mechanisms regulating systemic arterial blood pressure and pial microcirculation.

  14. Retinal and choroidal oxygen saturation of the optic nerve head in open-angle glaucoma subjects by multispectral imaging

    PubMed Central

    Li, Gai-yun; Al-wesabi, Samer abdo; Zhang, Hong

    2016-01-01

    Abstract The aim of this study was to determine whether differences exist in oxygen supply to the optic nerve head (ONH) from the retinal and choroidal vascular layers in patients with primary open angle glaucoma (POAG) using multispectral imaging (MSI).This ia an observational, cross-sectional study. Multispectral images were acquired from 38 eyes of 19 patients with POAG, and 42 healthy eyes from 21 matched volunteers with Annidis’ RHA multispectral digital ophthalmoscopy. Superficial and deeper oxygen saturation of the optic disc was represented by the mean gray scale values on the retinal and choroidal oxy-deoxy maps, respectively. Statistical analysis was performed to detect differences in ONH oxygen saturation between the 2 groups. Oxygen saturation levels in the eyes of POAG patients with severe glaucoma were compared to those of fellow eyes from the same subjects. Linear correlation analysis was performed to assess the association between ONH oxygen saturation and systemic and ocular parameters. No statistical difference was found in retinal and choroidal oxygen saturation between the POAG and control groups. In the glaucoma patients, retinal oxygen saturation was lower for eyes with worse visual fields than in those with good visual fields (t = 4.009, P = 0.001). In POAG patients, retinal oxygen saturation was dependent on mean defect of visual field and retinal nerve fiber layer thickness (RNFLT) (r = 0.511, 0.504, P = 0.001, 0.001, respectively), whereas the choroid vasculature oxygen saturation was inversely related to RNFLT (r = −0.391, P = 0.015). An age-dependent increase in retinal oxygen saturation was found for both the POAG and control groups (r = 0.473, 0.410, P = 0.007, 0.003, respectively). MSI revealed a significant correlation between functional and structural impairments in glaucoma and retinal oxygen saturation. MSI could provide objective assessments of perfusion impairments of the glaucomatous ONH

  15. Retinal and choroidal oxygen saturation of the optic nerve head in open-angle glaucoma subjects by multispectral imaging.

    PubMed

    Li, Gai-Yun; Al-Wesabi, Samer Abdo; Zhang, Hong

    2016-12-01

    The aim of this study was to determine whether differences exist in oxygen supply to the optic nerve head (ONH) from the retinal and choroidal vascular layers in patients with primary open angle glaucoma (POAG) using multispectral imaging (MSI).This ia an observational, cross-sectional study.Multispectral images were acquired from 38 eyes of 19 patients with POAG, and 42 healthy eyes from 21 matched volunteers with Annidis' RHA multispectral digital ophthalmoscopy. Superficial and deeper oxygen saturation of the optic disc was represented by the mean gray scale values on the retinal and choroidal oxy-deoxy maps, respectively. Statistical analysis was performed to detect differences in ONH oxygen saturation between the 2 groups. Oxygen saturation levels in the eyes of POAG patients with severe glaucoma were compared to those of fellow eyes from the same subjects. Linear correlation analysis was performed to assess the association between ONH oxygen saturation and systemic and ocular parameters.No statistical difference was found in retinal and choroidal oxygen saturation between the POAG and control groups. In the glaucoma patients, retinal oxygen saturation was lower for eyes with worse visual fields than in those with good visual fields (t = 4.009, P = 0.001). In POAG patients, retinal oxygen saturation was dependent on mean defect of visual field and retinal nerve fiber layer thickness (RNFLT) (r = 0.511, 0.504, P = 0.001, 0.001, respectively), whereas the choroid vasculature oxygen saturation was inversely related to RNFLT (r = -0.391, P = 0.015). An age-dependent increase in retinal oxygen saturation was found for both the POAG and control groups (r = 0.473, 0.410, P = 0.007, 0.003, respectively).MSI revealed a significant correlation between functional and structural impairments in glaucoma and retinal oxygen saturation. MSI could provide objective assessments of perfusion impairments of the glaucomatous ONH. This is a

  16. [The effect of destruction of rat capsaicin-sensitive nerves on blood pressure in rats with metabolic syndrome].

    PubMed

    Spiridonov, V K; Tolochko, Z S; Kostina, N E

    2013-09-01

    The effect of destruction of capsaicin-sensitive nerve (capsaicin 150 mg/kg, s/c) on blood pre- ssure was investigated in rats with metabolic syndrome induced by fructose (12.5% in drinking water for 10 weeks). The blood plasma concentrations of glucose, triglyceride (TG) and products of lipid perioxidation were defined in these rats. The systolic blood pressure was measured by non-invasive method using the Coda system (Coda, Kent Scientific, USA). The fructose diet caused impaired tolerance glucose, arterial hypertension, increased the contents of TG and products of lipid peroxidation. In capsaicin--pretreated rats (deafferentiation of capsaicin-sensitive nerve) the fructose intake did not evoke impairment tolerance glucose, the increase of systolic blood pressure and the plasma content of triglyceride. The increase of lipid perioxidation in fructose fed rats was not prevented by capsaicin pretreatment. The authors suggest that capsaicin-sensitive nerves contribute to the development of insulin resistance and arterial hypertension in the metabolic syndrome.

  17. Severity and Patterns of Blood-Nerve Barrier Breakdown in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy: Correlations with Clinical Subtypes

    PubMed Central

    Shimizu, Fumitaka; Sawai, Setsu; Sano, Yasuteru; Beppu, Minako; Misawa, Sonoko; Nishihara, Hideaki; Koga, Michiaki; Kuwabara, Satoshi; Kanda, Takashi

    2014-01-01

    Objective Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is currently classified into clinical subtypes, including typical and atypical forms (multifocal acquired demyelinating sensory and motor neuropathy (MADSAM) and distal acquired demyelinating symmetric neuropathy (DADS)). The aim of this study was to elucidate the patterns and severity of breakdown of the blood-nerve barrier (BNB) in each CIDP subtype. Methods We evaluated the effects of sera obtained from patients with typical CIDP, MADSAM and DADS and control subjects on the expression levels of tight junction proteins and transendothelial electrical resistance (TEER) value in human peripheral nerve microvascular endothelial cells (PnMECs). Results The sera obtained from the patients with the three clinical phenotypes of CIDP decreased the amount of claudin-5 protein levels and TEER values in the PnMECs. In addition, the sera obtained from typical CIDP patients more prominently reduced claudin-5 protein levels and TEER values in the PnMECs than did that obtained from the MADSAM and DADS patients. Furthermore, the severity of BNB disruption after exposure to the sera was associated with higher Hughes grade, lower MRC score, more pronounced slowing of motor nerve conduction in the median nerve and higher frequency of abnormal temporal dispersion. Conclusions Sera derived from typical CIDP patients destroy the BNB more severely than those from MADSAM or DADS patients. The extent of BNB disruption in the setting of CIDP is associated with clinical disability and demyelination in the nerve trunk. These observations may explain the phenotypical differences between CIDP subtypes. PMID:25105500

  18. Blood-nerve barrier: distribution of anionic sites on the endothelial plasma membrane and basal lamina of dorsal root ganglia.

    PubMed

    Bush, M S; Reid, A R; Allt, G

    1991-09-01

    Previous investigations of the blood-nerve barrier have correlated the greater permeability of ganglionic endoneurial vessels, compared to those of nerve trunks, with the presence of fenestrations and open intercellular junctions. Recent studies have demonstrated reduced endothelial cell surface charge in blood vessels showing greater permeability. To determine the distribution of anionic sites on the plasma membranes and basal laminae of endothelial cells in dorsal root ganglia, cationic colloidal gold and cationic ferritin were used. Electron microscopy revealed the existence of endothelial microdomains with differing labelling densities. Labelling indicated that caveolar and fenestral diaphragms and basal laminae are highly anionic at physiological pH, luminal plasma membranes and endothelial processes are moderately charged and abluminal plasma membranes are weakly anionic. Tracers did not occur in caveolae or cytoplasmic vesicles. In vitro tracer experiments at pH values of 7.3, 5.0, 3.5 and 2.0 indicated that the anionic charge on the various endothelial domains was contributed by chemical groups with differing pKa values. In summary, the labelling of ganglionic and sciatic nerve vessels was similar except for the heavy labelling of diaphragms in a minority of endoneurial vessels in ganglia. This difference is likely to account in part for the greater permeability of ganglionic endoneurial vessels. The results are discussed with regard to the blood-nerve and -brain barriers and vascular permeability in other tissues and a comparison made between the ultrastructure and anionic microdomains of epi-, peri- and endoneurial vessels of dorsal root ganglia and sciatic nerves.

  19. Shape changes induced by biologically active peptides and nerve growth factor in blood platelets of rabbits.

    PubMed

    Gudat, F; Laubscher, A; Otten, U; Pletscher, A

    1981-11-01

    1 Nerve growth factor (NGF), substance P (SP) and thymopoietin all caused shape change reactions of rapid onset in rabbit platelets. NGF had the highest maximal effect, and SP the lowest EC50 (concentration causing half maximal shape change). The action of SP was reversible within 5 min, whereas that of NGF lasted for at least 1 h. A series of other peptides were inactive. 2 After preincubation of platelets with SP, a second application of SP no longer caused a shape change reaction, whereas the effect of NGF was not influenced. 3 An oxidized NGF-derivative without biological activity did not cause a shape change reaction, neither did epidermal growth factor. 4 Prostaglandin E1 (PGE1) and pretreatment of the platelets with 3% butanol, which counteract the shape changes caused by 5-hydroxytryptamine (5-HT) and adenosine 3',5'-diphosphate, also antagonized those induced by NGF and SP. Neither heparin nor methysergide, an antagonist of 5-HT-receptors, influenced the shape change induced by NGF or SP. The action of NGF was also antagonized by a specific antibody to NGF. 5 Thymopoietin, like the basic polypeptide polyornithine (mol. wt. 40,000) was not antagonized by PGE1 and butanol. Heparin, which counteracted the effect of polyornithine, did not influence that of thymopoietin. 6 In conclusion, different modes of action are involved in the shape change of blood platelets induced by polypeptides and proteins. SP and NGF may act by stimulating specific membrane receptors.

  20. Head Injuries

    MedlinePlus

    ... scalp internal head injuries, which may involve the skull, the blood vessels within the skull, or the brain Fortunately, most childhood falls or ... knock the brain into the side of the skull or tear blood vessels. Some internal head injuries ...

  1. A Framework for Detecting Glaucomatous Progression in the Optic Nerve Head of an Eye using Proper Orthogonal Decomposition

    PubMed Central

    Balasubramanian, Madhusudhanan; Žabić, Stanislav; Bowd, Christopher; Thompson, Hilary W.; Wolenski, Peter; Iyengar, S. Sitharama; Karki, Bijaya B.; Zangwill, Linda M.

    2009-01-01

    Glaucoma is the second leading cause of blindness worldwide. Often the optic nerve head (ONH) glaucomatous damage and ONH changes occur prior to visual field loss and are observable in vivo. Thus, digital image analysis is a promising choice for detecting the onset and/or progression of glaucoma. In this work, we present a new framework for detecting glaucomatous changes in the ONH of an eye using the method of proper orthogonal decomposition (POD). A baseline topograph subspace was constructed for each eye to describe the structure of the ONH of the eye at a reference/baseline condition using POD. Any glaucomatous changes in the ONH of the eye present during a follow-up exam were estimated by comparing the follow-up ONH topography with its baseline topograph subspace representation. Image correspondence measures of L1 and L2 norms, correlation, and image Euclidean distance (IMED) were used to quantify the ONH changes. An ONH topographic library built from the Louisiana State University Experimental Glaucoma study was used to evaluate the performance of the proposed method. The area under the receiver operating characteristic curves (AUC) were used to compare the diagnostic performance of the POD induced parameters with the parameters of Topographic Change Analysis (TCA) method. The IMED and L2 norm parameters in the POD framework provided the highest AUC of 0.94 at 10° field of imaging and 0.91 at 15° field of imaging compared to the TCA parameters with an AUC of 0.86 and 0.88 respectively. The proposed POD framework captures the instrument measurement variability and inherent structure variability and shows promise for improving our ability to detect glaucomatous change over time in glaucoma management. PMID:19369163

  2. Detection of the optic nerve head in fundus images of the retina using the Hough transform for circles.

    PubMed

    Zhu, Xiaolu; Rangayyan, Rangaraj M; Ells, Anna L

    2010-06-01

    Detection of the optic nerve head (ONH) is a key preprocessing component in algorithms for the automatic extraction of the anatomical structures of the retina. We propose a method to automatically locate the ONH in fundus images of the retina. The method includes edge detection using the Sobel operators and detection of circles using the Hough transform. The Hough transform assists in the detection of the center and radius of a circle that approximates the margin of the ONH. Forty images of the retina from the Digital Retinal Images for Vessel Extraction (DRIVE) dataset were used to test the performance of the proposed method. The center and boundary of the ONH were independently marked by an ophthalmologist for evaluation. Free-response receiver operating characteristics (FROC) analysis as well as measures of distance and overlap were used to evaluate the performance of the proposed method. The centers of the ONH were detected with an average distance of 0.36 mm to the corresponding centers marked by the ophthalmologist; the detected circles had an average overlap of 0.73 with the boundaries of the ONH drawn by the ophthalmologist. FROC analysis indicated a sensitivity of detection of 92.5% at 8.9 false-positives per image. With an intensity-based criterion for the selection of the circle and a limit of 40 pixels (0.8 mm) on the distance between the center of the detected circle and the manually identified center of the ONH, a successful detection rate of 90% was obtained with the DRIVE dataset.

  3. Optic Nerve Head Measurements With Optical Coherence Tomography: A Phantom-Based Study Reveals Differences Among Clinical Devices

    PubMed Central

    Agrawal, Anant; Baxi, Jigesh; Calhoun, William; Chen, Chieh-Li; Ishikawa, Hiroshi; Schuman, Joel S.; Wollstein, Gadi; Hammer, Daniel X.

    2016-01-01

    Purpose Optical coherence tomography (OCT) can monitor for glaucoma by measuring dimensions of the optic nerve head (ONH) cup and disc. Multiple clinical studies have shown that different OCT devices yield different estimates of retinal dimensions. We developed phantoms mimicking ONH morphology as a new way to compare ONH measurements from different clinical OCT devices. Methods Three phantoms were fabricated to model the ONH: One normal and two with glaucomatous anatomies. Phantoms were scanned with Stratus, RTVue, and Cirrus clinical devices, and with a laboratory OCT system as a reference. We analyzed device-reported ONH measurements of cup-to-disc ratio (CDR) and cup volume and compared them with offline measurements done manually and with a custom software algorithm, respectively. Results The mean absolute difference between clinical devices with device-reported measurements versus offline measurements was 0.082 vs. 0.013 for CDR and 0.044 mm3 vs. 0.019 mm3 for cup volume. Statistically significant differences between devices were present for 16 of 18 comparisons of device-reported measurements from the phantoms. Offline Cirrus measurements tended to be significantly different from those from Stratus and RTVue. Conclusions The interdevice differences in CDR and cup volume are primarily caused by the devices' proprietary ONH analysis algorithms. The three devices yield more similar ONH measurements when a consistent offline analysis technique is applied. Scan pattern on the ONH also may be a factor in the measurement differences. This phantom-based study has provided unique insights into characteristics of OCT measurements of the ONH. PMID:27409500

  4. Role of endothelin-A receptors in optic nerve head red cell flux regulation during isometric exercise in healthy humans.

    PubMed

    Boltz, Agnes; Schmidl, Doreen; Werkmeister, René M; Lasta, Michael; Kaya, Semira; Palkovits, Stefan; Told, Reinhard; Frantal, Sophie; Garhöfer, Gerhard; Schmetterer, Leopold

    2013-01-01

    Endothelin-1 (ET-1) is an important regulator of vascular tone in the eye. It appears to play a role in ocular disease because of its strong vasoconstrictor action, its role in intraocular pressure homeostasis, and its neurotoxic potential. We have previously shown that ET-1 is involved in choroidal red cell flux (RCF) regulation during isometric exercise in healthy humans. In the present study we hypothesized that ET-1 also plays a role in optic nerve head (ONH) RCF regulation during isometric exercise. To test this hypothesis, we performed a randomized, double-masked, placebo-controlled, two-way crossover study in 15 healthy volunteers. Subjects were randomized to receive intravenous infusions of the specific endothelin type A receptor antagonist BQ-123 and placebo on two different study days. During these infusion periods, subjects performed squatting for 6 min to increase ocular perfusion pressure (OPP). ONH RCF was assessed with laser-Doppler flowmetry, and OPP was calculated from mean arterial pressure and intraocular pressure. BQ-123 did not change OPP or ONH RCF at baseline. The relative increase in OPP during isometric exercise was comparable between both groups (between 84 and 88%, P = 0.76 between groups; P < 0.001 vs. baseline). Isometric exercise increased ONH RCF during placebo and BQ-123, but the increase was more pronounced when the endothelin type-A receptor antagonist was administered (placebo, 27.3 ± 5.4%; and BQ-123, 39.2 ± 4.4%; P = 0.007 between groups). The present data indicate that ET-1 regulates red cell flux in the ONH beyond the autoregulatory range.

  5. Early detection of glaucoma using fully automated disparity analysis of the optic nerve head (ONH) from stereo fundus images

    NASA Astrophysics Data System (ADS)

    Sharma, Archie; Corona, Enrique; Mitra, Sunanda; Nutter, Brian S.

    2006-03-01

    Early detection of structural damage to the optic nerve head (ONH) is critical in diagnosis of glaucoma, because such glaucomatous damage precedes clinically identifiable visual loss. Early detection of glaucoma can prevent progression of the disease and consequent loss of vision. Traditional early detection techniques involve observing changes in the ONH through an ophthalmoscope. Stereo fundus photography is also routinely used to detect subtle changes in the ONH. However, clinical evaluation of stereo fundus photographs suffers from inter- and intra-subject variability. Even the Heidelberg Retina Tomograph (HRT) has not been found to be sufficiently sensitive for early detection. A semi-automated algorithm for quantitative representation of the optic disc and cup contours by computing accumulated disparities in the disc and cup regions from stereo fundus image pairs has already been developed using advanced digital image analysis methodologies. A 3-D visualization of the disc and cup is achieved assuming camera geometry. High correlation among computer-generated and manually segmented cup to disc ratios in a longitudinal study involving 159 stereo fundus image pairs has already been demonstrated. However, clinical usefulness of the proposed technique can only be tested by a fully automated algorithm. In this paper, we present a fully automated algorithm for segmentation of optic cup and disc contours from corresponding stereo disparity information. Because this technique does not involve human intervention, it eliminates subjective variability encountered in currently used clinical methods and provides ophthalmologists with a cost-effective and quantitative method for detection of ONH structural damage for early detection of glaucoma.

  6. Optic nerve head parameters of high-definition optical coherence tomography and Heidelberg retina tomogram in perimetric and preperimetric glaucoma

    PubMed Central

    Begum, Viquar Unnisa; Addepalli, Uday Kumar; Senthil, Sirisha; Garudadri, Chandra Sekhar; Rao, Harsha Laxmana

    2016-01-01

    Background: Heidelberg retina tomogram (HRT) and optical coherence tomography (OCT) are two widely used imaging modalities to evaluate the optic nerve head (ONH) in glaucoma. Purpose: To compare the ONH parameters of HRT3 and high-definition OCT (HD-OCT) and evaluate their diagnostic abilities in perimetric and preperimetric glaucoma. Design: Cross-sectional analysis. Methods: 35 control eyes (24 subjects), 21 preperimetric glaucoma eyes (15 patients), and 64 perimetric glaucoma eyes (44 patients) from the Longitudinal Glaucoma Evaluation Study underwent HRT3 and HD-OCT examinations. Statistical Analysis: Agreement between the ONH parameters of HRT and HD-OCT were assessed using Bland-Altman plots. Diagnostic abilities of ONH parameters were evaluated using area under the receiver operating characteristic curves (AUCs), sensitivity at fixed specificity, and likelihood ratios (LR). Results: Optic disc area, vertical cup to disc ratio, and cup volume with HD-OCT were larger than with HRT, while the rim area was smaller with HD-OCT (P < 0.001 for all comparisons). AUCs of all HD-OCT ONH parameters (0.90-0.97 in perimetric and 0.62-0.71 in preperimetric glaucoma) were comparable (P > 0.10) to the corresponding HRT ONH parameters (0.81-0.95 in perimetric and 0.55-0.72 in preperimetric glaucoma). LRs associated with diagnostic categorization of ONH parameters of both HD-OCT and HRT were associated with larger effects on posttest probability of perimetric compared to preperimetric glaucoma. Conclusions: ONH measurements of HD-OCT and HRT3 cannot be used interchangeably. Though the diagnostic abilities of ONH parameters of HD-OCT and HRT in glaucoma were comparable, the same were significantly lower in preperimetric compared to perimetric glaucoma. PMID:27221679

  7. Simulated Microgravity Increases Cutaneous Blood Flow in the Head and Leg of Humans

    NASA Technical Reports Server (NTRS)

    Stout, M. Shannon; Watenpaugh, Donald E.; Breit, Gregory A.; Hargens, Alan R.

    1995-01-01

    The cutaneous micro-circulation vasodilates during acute 6 deg. head-down tilt (HDT, simulated microgravity) relative to upright conditions, more in the lower body than in the upper body. We expected that relative magnitudes of and differences between upper and lower body cutaneous blood flow elevation would be sustained during initial acclimation to simulated microgravity. We measured cutaneous micro-vascular blood flow with laser-Doppler flowmetry at the leg (over the distal tibia) and cheek (over the zygomatic arch) of eight healthy men before, during, and after 24 h of HDT. Results were calculated as a percentage of baseline value (100% measured during pre-tilt upright sitting). Cutaneous blood flow in the cheek increased significantly to 165 +/- 37% (mean + SE, p less than 0.05) at 9-12 h HDT, then returned to near baseline values by 24 h HDT (114 +/- 29%, NSD), despite increased local arterial pressure. Microvascular flow in the leg remained significantly elevated above baseline throughout 24 h HDT (427 +/- 85% at 3 h HDT and 215 +/- 142% at 24 h HDT, p less than 0.05). During the 6-h upright sitting recovery period, cheek and leg blood flow levels returned to near pre-tilt baseline values. Because hydrostatic effects of HDT increase local arterial pressure at the carotid sinus, baroreflex-mediated withdrawal of sympathetic tone probably contributed to increased microvascular flows at the head and leg during HDT. In the leg, baroreflex effects combined with minimal stimulation of local veno-arteriolar and myogenic autoregulatory vasoconstriction to elicit relatively larger and more sustained increases in cutaneous flow during HDT. In the cheek, delayed myogenic vasoconstriction and/or humoral effects apparently compensated for flow elevation by 24 h of HDT. Therefore, localized vascular adaptations to gravity probably explain differences in acclimation of lower and upper body blood flow to HDT and actual microgravity.

  8. A magnetically levitated centrifugal blood pump with a simple-structured disposable pump head.

    PubMed

    Hijikata, Wataru; Shinshi, Tadahiko; Asama, Junichi; Li, Lichuan; Hoshi, Hideo; Takatani, Setsuo; Shimokohbe, Akira

    2008-07-01

    A magnetically levitated centrifugal blood pump (MedTech Dispo) has been developed for use in a disposable extracorporeal system. The design of the pump is intended to eliminate mechanical contact with the impeller, to facilitate a simple disposable mechanism, and to reduce the blood-heating effects that are caused by motors and magnetic bearings. The bearing rotor attached to the impeller is suspended by a two degrees-of-freedom controlled radial magnetic bearing stator, which is situated outside the rotor. In the space inside the ringlike rotor, a magnetic coupling disk is placed to rotate the rotor and to ensure that the pump head is thermally isolated from the motor. In this system, the rotor can exhibit high passive stiffness due to the novel design of the closed magnetic circuits. The disposable pump head, which has a priming volume of 23 mL, consists of top and bottom housings, an impeller, and a rotor with a diameter of 50 mm. The pump can provide a head pressure of more than 300 mm Hg against a flow of 5 L/min. The normalized index of hemolysis of the MedTech Dispo is 0.0025 +/- 0.0005 g/100 L at 5 L/min against 250 mm Hg. This is one-seventh of the equivalent figure for a Bio Pump BPX-80 (Medtronic, Inc., Minneapolis, MN, USA), which has a value of 0.0170 +/- 0.0096 g/100 L. These results show that the MedTech Dispo offers high pumping performance and low blood trauma.

  9. Variation in response dynamics of regular and irregular vestibular-nerve afferents during sinusoidal head rotations and currents in the chinchilla.

    PubMed

    Kim, Kyu-Sung; Minor, Lloyd B; Della Santina, Charles C; Lasker, David M

    2011-05-01

    In mammals, vestibular-nerve afferents that innervate only type I hair cells (calyx-only afferents) respond nearly in phase with head acceleration for high-frequency motion, whereas afferents that innervate both type I and type II (dimorphic) or only type II (bouton-only) hair cells respond more in phase with head velocity. Afferents that exhibit irregular background discharge rates have a larger phase lead re-head velocity than those that fire more regularly. The goal of this study was to investigate the cause of the variation in phase lead between regular and irregular afferents at high-frequency head rotations. Under the assumption that externally applied galvanic currents act directly on the nerve, we derived a transfer function describing the dynamics of a semicircular canal and its hair cells through comparison of responses to sinusoidally modulated head velocity and currents. Responses of all afferents were fit well with a transfer function with one zero (lead term). Best-fit lead terms describing responses to current for each group of afferents were similar to the lead term describing responses to head velocity for regular afferents (0.006 s + 1). This finding indicated that the pre-synaptic and synaptic inputs to regular afferents were likely to be pure velocity transducers. However, the variation in phase lead between regular and irregular afferents could not be explained solely by the ratio of type I to II hair cells (Baird et al 1988), suggesting that the variation was caused by a combination of pre- (type of hair cell) and post-synaptic properties.

  10. Multiple stimulations for muscle-nerve-blood vessel unit in compensatory hypertrophied skeletal muscle of rat surgical ablation model.

    PubMed

    Tamaki, Tetsuro; Uchiyama, Yoshiyasu; Okada, Yoshinori; Tono, Kayoko; Nitta, Masahiro; Hoshi, Akio; Akatsuka, Akira

    2009-07-01

    Tissue inflammation and multiple cellular responses in the compensatory enlarged plantaris (OP Plt) muscle induced by surgical ablation of synergistic muscles (soleus and gastrocnemius) were followed over 10 weeks after surgery. Contralateral surgery was performed in adult Wistar male rats. Cellular responses in muscle fibers, blood vessels and nerve fibers were analyzed by immunohistochemistry and electron microscopy. Severe muscle fiber damage and disappearance of capillaries associated with apparent tissue edema were observed in the peripheral portion of OP Plt muscles during the first week, whereas central portions were relatively preserved. Marked cell activation/proliferation was also mainly observed in peripheral portions. Similarly, activated myogenic cells were seen not only inside but also outside of muscle fibers. The former were likely satellite cells and the latter may be interstitial myogenic cells. One week after surgery, small muscle fibers, small arteries and capillaries and several branched-muscle fibers were evident in the periphery, thus indicating new muscle fiber and blood vessel formation. Proliferating cells were also detected in the nerve bundles in the Schwann cell position. These results indicate that the compensatory stimulated/enlarged muscle is a suitable model for analyzing multiple physiological cellular responses in muscle-nerve-blood vessel units under continuous stretch stimulation.

  11. Traumatic Brain Injury by a Closed Head Injury Device Induces Cerebral Blood Flow Changes and Microhemorrhages

    PubMed Central

    Kallakuri, Srinivasu; Bandaru, Sharath; Zakaria, Nisrine; Shen, Yimin; Kou, Zhifeng; Zhang, Liying; Haacke, Ewart Mark; Cavanaugh, John M

    2015-01-01

    Objectives: Traumatic brain injury is a poly-pathology characterized by changes in the cerebral blood flow, inflammation, diffuse axonal, cellular, and vascular injuries. However, studies related to understanding the temporal changes in the cerebral blood flow following traumatic brain injury extending to sub-acute periods are limited. In addition, knowledge related to microhemorrhages, such as their detection, localization, and temporal progression, is important in the evaluation of traumatic brain injury. Materials and Methods: Cerebral blood flow changes and microhemorrhages in male Sprague Dawley rats at 4 h, 24 h, 3 days, and 7 days were assessed following a closed head injury induced by the Marmarou impact acceleration device (2 m height, 450 g brass weight). Cerebral blood flow was measured by arterial spin labeling. Microhemorrhages were assessed by susceptibility-weighted imaging and Prussian blue histology. Results: Traumatic brain injury rats showed reduced regional and global cerebral blood flow at 4 h and 7 days post-injury. Injured rats showed hemorrhagic lesions in the cortex, corpus callosum, hippocampus, and brainstem in susceptibility-weighted imaging. Injured rats also showed Prussian blue reaction products in both the white and gray matter regions up to 7 days after the injury. These lesions were observed in various areas of the cortex, corpus callosum, hippocampus, thalamus, and midbrain. Conclusions: These results suggest that changes in cerebral blood flow and hemorrhagic lesions can persist for sub-acute periods after the initial traumatic insult in an animal model. In addition, microhemorrhages otherwise not seen by susceptibility-weighted imaging are present in diverse regions of the brain. The combination of altered cerebral blood flow and microhemorrhages can potentially be a source of secondary injury changes following traumatic brain injury and may need to be taken into consideration in the long-term care of these cases. PMID:26605126

  12. Simulated Microgravity Increases Cutaneous Blood Flow in the Head and Leg of Humans

    NASA Technical Reports Server (NTRS)

    Stout, M. Shannon; Watenpaugh, Donald E.; Breit, Gregory A.; Hargens, Alan R.

    1995-01-01

    The cutaneous microcirculation vasodilates during acute 6 degree head-down tilt (HDT, simulated microgravity) relative to upright conditions, more in the lower body than in the upper body. Cutaneous microvascular blood flow was measured with laser-Doppler flowmetry at the leg (over the distal tibia) and cheek (over the zygomatic arch) of eight healthy men before, during, and after 24 h of HDT. Results were calculated as a percentage of baseline value (100% measured during pre-tilt upright sitting). Cutaneous blood flow in the cheek increased significantly to 165 +/- 37% (mean +/- SE, p less than 0.05) at 9-12 h HDT, then returned to near baseline values by 24 h HDT (114 +/- 29%, NSD), despite increased local arterial pressure. Microvascular flow in the leg remained significantly elevated above baseline througout 24 h HDT (427 +/- 85% at 3 h HDT and 215 +/- 142% at 24 h HDT, p less than 0.05). During the 6-h upright sitting recovery period, cheek and leg blood flow levels returned to near pre-tilt baseline values. Because hydrostatic effects of HDT increase local arterial pressure at the carotid sinus, baroreflex-mediated withdrawal of sympathetic tone probably contributed to increased microvascular flows at the head and leg during HDT. In the leg baroreflex effects combined with minimal stimulation of local veno-arteriolar and myogenic autoregulatory vasoconstriction to elicit relatively larger and more sustained increases in cutaneous flow during HDT. In the cheek, delayed myogenic vasoconstriction and/or hurmonal effects apparently compensated for flow elevation by 24 h of HDT. Therefore, localized vascular adaptations to gravity probably explain differences in acclimation of lower and upper body blood flow to HDT and actual microgravity.

  13. Effect of Treating Streptozotocin-Induced Diabetic Rats With Sorbinil, Myo-Inositol or Aminoguanidine on Endoneurial Blood Flow, Motor Nerve Conduction Velocity and Vascular Function of Epineurial Arterioles of the Sciatic Nerve

    PubMed Central

    Coppey, Lawrence J.; Gellett, Jill S.; Davidson, Eric P.; Dunlap, Joyce A.

    2002-01-01

    Previously we have demonstrated that diabetes causes impairment in vascular function of epineurial vessels, which precedes the slowing of motor nerve conduction velocity. Treatment of diabetic rats with aldose reductase inhibitors, aminoguanidine or myo-inositol supplementation have been shown to improve motor nerve conduction velocity and/or decreased endoneurial blood flow. However, the effect these treatments have on vascular reactivity of epineurial vessels of the sciatic nerve is unknown. In these studies we examined the effect of treating streptozotocininduced rats with sorbinil, aminoguanidine or myo-inositol on motor nerve conduction velocity, endoneurial blood flow and endothelium dependent vascular relaxation of arterioles that provide circulation to the region of the sciatic nerve. Treating diabetic rats with sorbinil, aminoguanidine or myo-inositol improved the reduction of endoneurial blood flow and motor nerve conduction velocity. However, only sorbinil treatment significantly improved the diabetes-induced impairment of acetylcholinemediated vasodilation of epineurial vessels of the sciatic nerve. All three treatments were efficacious in preventing the appropriate metabolic derangements associated with either activation of the polyol pathway or increased nonenzymatic glycation. In addition, sorbinil was shown to prevent the diabetes-induced decrease in lens glutathione level. However, other markers of oxidative stress were not vividly improved by these treatments. These studies suggest that sorbinil treatment may be more effective in preventing neural dysfunction in diabetes than either aminoguanidine or myoinositol. PMID:11900277

  14. CSF Hypernatremia Elevates Sympathetic Nerve Activity and Blood Pressure via the Rostral Ventrolateral Medulla

    PubMed Central

    Stocker, Sean D.; Lang, Susan M.; Simmonds, Sarah S.; Wenner, Megan M.; Farquhar, William B.

    2015-01-01

    Elevated NaCl concentrations of the cerebrospinal fluid (CSF) increase sympathetic nerve activity (SNA) in salt-sensitive hypertension. Neurons of the rostral ventrolateral medulla (RVLM) play a pivotal role in the regulation of SNA and receive mono- or poly-synaptic inputs from several hypothalamic structures responsive to hypernatremia. Therefore, the present study investigated the contribution of RVLM neurons to the SNA and pressor response to CSF hypernatremia. Lateral ventricle infusion of 0.15M, 0.6M, and 1.0M NaCl (5µL/10 min) produced concentration-dependent increases in lumbar SNA, adrenal SNA, and arterial blood pressure (ABP) despite no change in splanchnic SNA and a decrease in renal SNA. Ganglionic blockade with chlorisondamine or acute lesion of the lamina terminalis blocked or significantly attenuated these responses, respectively. RVLM microinjection of the GABAA agonist muscimol abolished the sympathoexcitatory response to ICV infusion of 1M NaCl. Furthermore, blockade of ionotropic glutamate, but not angiotensin II type 1, receptors significantly attenuated the increase in lumbar SNA, adrenal SNA, and ABP. Finally, single-unit recordings of spinally-projecting RVLM neurons revealed three distinct populations based on discharge responses to ICV infusion of 1M NaCl: Type I excited (46%, 11/24), Type II inhibited (37%, 9/24), and Type III no change (17%, 4/24). All neurons with slow conduction velocities were Type I cells. Collectively, these findings suggest that acute increases in CSF NaCl concentrations selectively activate a discrete population of RVLM neurons through glutamate receptor activation to increase SNA and ABP. PMID:26416846

  15. Comparing Optic Nerve Head Rim Width, Rim Area, and Peripapillary Retinal Nerve Fiber Layer Thickness to Axon Count in Experimental Glaucoma

    PubMed Central

    Fortune, Brad; Hardin, Christy; Reynaud, Juan; Cull, Grant; Yang, Hongli; Wang, Lin; Burgoyne, Claude F.

    2016-01-01

    Purpose We compare spectral-domain optical coherence tomography (SDOCT) measurements of minimum rim width (MRW), minimum rim area (MRA), and peripapillary retinal nerve fiber layer thickness (RNFLT) to complete orbital optic nerve axon counts in nonhuman primates (NHP) with unilateral experimental glaucoma (EG). Methods Biweekly SDOCT measurements of MRW, MRA, and RNFLT were acquired under manometric IOP control (10 mm Hg) in 51 NHP during baseline (mean ± SD, 5.0 ± 1.6 sessions) and after laser photocoagulation was applied to the trabecular meshwork of one eye to induce chronic IOP elevation. At the study endpoint (predefined for each NHP), 100% axon counts were obtained from each optic nerve. Results For SDOCT parameters at baseline, the correlation between the two eyes of each animal was strongest for RNFLT (R = 0.97) and MRW (R = 0.97), but lower for MRA (R = 0.85). At the final time point, average values in EG eyes relative to control eyes were: −22% for RNFLT, −38% for MRW, −36% for MRA, and −36% for optic nerve axons. The correlation with axon counts was strongest for RNFLT (R = 0.81), compared to MRW (R = 0.72, P = 0.001) or MRA (R = 0.70, P = 0.001). Diagnostic sensitivity was 75% for RNFLT, 90% for MRW, and 88% for MRA; all had 100% specificity. Conclusions Peripapillary RNFLT was correlated more closely with total orbital optic nerve axon count than were the ONH parameters MRW or MRA. This is likely because glaucomatous deformation (beyond axon loss alone) has a greater influence on the ONH parameters MRW and MRA than on RNFLT. PMID:27409499

  16. Augmentation of venous, arterial and microvascular blood supply in the leg by isometric neuromuscular stimulation via the peroneal nerve

    PubMed Central

    Tucker, AT; Maass, A; Bain, DS; Chen, L-H; Azzam, M; Dawson, H; Johnston, A

    2010-01-01

    BACKGROUND: Deep vein thrombosis (DVT) is the formation of a blood clot within the deep veins. During periods of sitting, blood flow is decreased and this contributes to an increased risk of DVT. Trials have shown that 5% to 10% of passengers undertaking long-haul flights develop asymptomatic calf DVT. AIM: To investigate the safety and efficacy of a novel neuromuscular device that augments peripheral blood flow. METHODS: Thirty healthy volunteers were assessed while seated. Each subject had one leg connected to the stimulator and the other leg immobile acting as control. Fifteen sequential electrical stimulations were applied for 5 min each followed by a 10 min recovery phase. The following noninvasive measurements were performed before, during and after the stimulation programs: photoplethysmography, strain gauge plethysmography, laser Doppler fluxmetry, transcutaneous oxygen tension, pulse oximetry, superficial femoral vein blood flow and vessel diameter (ultrasound); discomfort questionnaires were also administered. RESULTS: During neuromuscular stimulation, significant increases in blood volume flow and velocity and skin capillary blood flow were found; transdermal skin oxygen levels were maintained. No changes were observed in heart rate, blood pressure, oxygen saturation or femoral vein vessel diameter. CONCLUSIONS: Using a newly developed device, electrical nerve stimulation of the lower leg significantly increased blood flow; the device in the present study is, therefore, a promising tool for the development of a novel DVT prevention device. Because this method of electrical nerve stimulation is virtually pain free, the present study has significant implications for the prevention of DVT in hospitals, outpatient settings and community care settings, as well as in preventing travel-related thrombosis. PMID:22477572

  17. Neurovascular decompression of the rostral ventrolateral medulla decreases blood pressure and sympathetic nerve activity in patients with refractory hypertension.

    PubMed

    Sasaki, Susumu; Tanda, Shuji; Hatta, Tsuguru; Morimoto, Satoshi; Takeda, Kazuo; Kizu, Osamu; Tamaki, Shinji; Saito, Mitsuru; Tamura, Yoji; Kondo, Akinori

    2011-11-01

    Recently, the authors experienced four patients who had refractory hypertension and neurovascular compression of the rostral ventrolateral medulla (RVLM). One of them, a 49-year-old woman, had undergone continuous intravenous drip injections of calcium channel blockers and β-blockers for more than 3 years because of severe and refractory hypertension. The patients had undergone microvascular decompression (MVD) of the RVLM, and the changes in blood pressure (BP) and sympathetic nerve activities were recorded. In these patients, BP decreased to the normal range without any antihypertensive drugs 2 to 3 months after MVD. The tibial sympathetic nerve activities under resting and stress conditions significantly decreased, and plasma levels of norepinephrine, urinary levels of adrenaline, and plasma renin activity were also significantly decreased after MVD of RVLM. In some patients with refractory hypertension, arterial compression of the RVLM enhances sympathetic nerve activity and renin-angiotensin system to thereby increase BP. In these patients, the operative decompression of the RVLM could lower BP via restoration of sympathetic nerve activities and the renin-angiotensin system.

  18. The prevalence of accessory heads of the flexor pollicis longus and the flexor digitorum profundus muscles in Egyptians and their relations to median and anterior interosseous nerves.

    PubMed

    El Domiaty, M A; Zoair, M M; Sheta, A A

    2008-02-01

    Entrapment neuropathy in the forearm is not uncommon. Surgical interference for nerve decompression should be preceded by accurate diagnosis of the exact cause and site of the nerve entrapment. The aim of the present study was to investigate the prevalence of accessory heads of the flexor pollicis longus and flexor digitorum profundus muscles (FPLah) and (FDPah) in Egyptians and their topographical relationship with both the median nerve and its anterior interosseous branch. A total of 42 upper limbs of embalmed cadavers, 36 from males and 6 from females, were examined to elucidate the prevalence of both the FPLah and the FDPah muscles, their origin, insertion, nerve supply and morphology. The distribution of these two muscles in the right and left male and female upper limbs and their relationship to the anterior interosseous and median nerves were recorded. The total lengths of both accessory muscles and the lengths of their fleshy bellies and tendons were also measured. The FPLah was found to be present more frequently (61.9%) than it was absent, whereas the FDPah was observed in only 14.24% of the specimens examined. The combination of the accessory muscles in the same forearm was noticed in 9.52% of cases. As regards side, the FPLah appeared in 77.7% of the right forearms and in 50% of the left, while the FDPah was found in only 25% of the left forearms. The accessory muscles showed no single morphology, as the FPLah appeared fusiform in 53.8%, slender in 30.8% and voluminous fusiform in 15.4%, while the FDPah was slender in 66.6% and triangular in 33.3% of specimens. The FPLah arose mainly from the under surface of flexor digitorum superficialis, while the FDPah took its origin from the under surface of flexor digitorum superficialis or from the medial epicondyle. The insertion of the FPLah was mainly into the upper third of the FPL tendon, while the FDPah tendon joined the tendons of the flexor digitorum profundus muscle to the index or middle and ring

  19. Inhibition of oxidative stress by coenzyme Q10 increases mitochondrial mass and improves bioenergetic function in optic nerve head astrocytes

    PubMed Central

    Noh, Y H; Kim, K-Y; Shim, M S; Choi, S-H; Choi, S; Ellisman, M H; Weinreb, R N; Perkins, G A; Ju, W-K

    2013-01-01

    Oxidative stress contributes to dysfunction of glial cells in the optic nerve head (ONH). However, the biological basis of the precise functional role of mitochondria in this dysfunction is not fully understood. Coenzyme Q10 (CoQ10), an essential cofactor of the electron transport chain and a potent antioxidant, acts by scavenging reactive oxygen species (ROS) for protecting neuronal cells against oxidative stress in many neurodegenerative diseases. Here, we tested whether hydrogen peroxide (100 μM H2O2)-induced oxidative stress alters the mitochondrial network, oxidative phosphorylation (OXPHOS) complex (Cx) expression and bioenergetics, as well as whether CoQ10 can ameliorate oxidative stress-mediated alterations in mitochondria of the ONH astrocytes in vitro. Oxidative stress triggered the activation of ONH astrocytes and the upregulation of superoxide dismutase 2 (SOD2) and heme oxygenase-1 (HO-1) protein expression in the ONH astrocytes. In contrast, CoQ10 not only prevented activation of ONH astrocytes but also significantly decreased SOD2 and HO-1 protein expression in the ONH astrocytes against oxidative stress. Further, CoQ10 prevented a significant loss of mitochondrial mass by increasing mitochondrial number and volume density and by preserving mitochondrial cristae structure, as well as promoted mitofilin and peroxisome-proliferator-activated receptor-γ coactivator-1 protein expression in the ONH astrocyte, suggesting an induction of mitochondrial biogenesis. Finally, oxidative stress triggered the upregulation of OXPHOS Cx protein expression, as well as reduction of cellular adeonsine triphosphate (ATP) production and increase of ROS generation in the ONH astocytes. However, CoQ10 preserved OXPHOS protein expression and cellular ATP production, as well as decreased ROS generation in the ONH astrocytes. On the basis of these observations, we suggest that oxidative stress-mediated mitochondrial dysfunction or alteration may be an important

  20. Mechanosensitive release of adenosine 5'-triphosphate through pannexin channels and mechanosensitive upregulation of pannexin channels in optic nerve head astrocytes: a mechanism for purinergic involvement in chronic strain.

    PubMed

    Beckel, Jonathan M; Argall, Arthur J; Lim, Jason C; Xia, Jingsheng; Lu, Wennan; Coffey, Erin E; Macarak, Edward J; Shahidullah, Mohammed; Delamere, Nicholas A; Zode, Gulab S; Sheffield, Val C; Shestopalov, Valery I; Laties, Alan M; Mitchell, Claire H

    2014-09-01

    As adenosine 5'-triphosphate (ATP) released from astrocytes can modulate many neural signaling systems, the triggers and pathways for this ATP release are important. Here, the ability of mechanical strain to trigger ATP release through pannexin channels and the effects of sustained strain on pannexin expression were examined in rat optic nerve head astrocytes. Astrocytes released ATP when subjected to 5% of equibiaxial strain or to hypotonic swelling. Although astrocytes expressed mRNA for pannexins 1-3, connexin 43, and VNUT, pharmacological analysis suggested a predominant role for pannexins in mechanosensitive ATP release, with Rho kinase contribution. Astrocytes from panx1(-/-) mice had reduced baseline and stimulated levels of extracellular ATP, confirming the role for pannexins. Swelling astrocytes triggered a regulatory volume decrease that was inhibited by apyrase or probenecid. The swelling-induced rise in calcium was inhibited by P2X7 receptor antagonists A438079 and AZ10606120, in addition to apyrase and carbenoxolone. Extended stretch of astrocytes in vitro upregulated expression of panx1 and panx2 mRNA. A similar upregulation was observed in vivo in optic nerve head tissue from the Tg-MYOC(Y437H) mouse model of chronic glaucoma; genes for panx1, panx2, and panx3 were increased, whereas immunohistochemistry confirmed increased expression of pannexin 1 protein. In summary, astrocytes released ATP in response to mechanical strain, with pannexin 1 the predominant efflux pathway. Sustained strain upregulated pannexins in vitro and in vivo. Together, these findings provide a mechanism by which extracellular ATP remains elevated under chronic mechanical strain, as found in the optic nerve head of patients with glaucoma.

  1. T cell abundance in blood predicts acute organ toxicity in chemoradiotherapy for head and neck cancer

    PubMed Central

    Reichardt, Sybille D.; Rave-Fränk, Margret; Schirmer, Markus A.; Stadelmann, Christine; Canis, Martin; Wolff, Hendrik A.

    2016-01-01

    Treatment of head and neck squamous cell carcinoma (HNSCC) by chemoradiotherapy (CRT) often results in high-grade acute organ toxicity (HGAOT). As these adverse effects impair the patients' quality of life and the feasibility of the planned therapy, we sought to analyze immunological parameters in tumor material and blood samples obtained from 48 HNSCC patients in order to assess the potential to predict the individual acute organ toxicity. T cells in the tumor stroma were enriched in patients developing HGAOT whereas levels of soluble factors in the plasma and gene expression in whole blood did not coincide with the occurrence of acute organ toxicity. In contrast, the frequency and absolute numbers of selected leukocyte subpopulations measured in samples of peripheral blood mononuclear cells (PBMCs) directly before the beginning of CRT were significantly different in patients with HGAOT as compared to those without. When we validated several potential markers including the abundance of T cells in a small prospective study with 16 HNSCC patients, we were able to correctly predict acute organ toxicity in up to 81% of the patients. We conclude that analysis of PBMCs by fluorescence-activated cell sorting (FACS) might be a convenient strategy to identify patients at risk of developing HGAOT caused by CRT, which might allow to adapt the treatment regimen and possibly improve disease outcome. PMID:27589568

  2. Liquid chromatography tandem mass spectrometry applied to quantitation of the organophosphorus nerve agent VX in microdialysates from blood probes.

    PubMed

    Stubbs, S J; Read, R W

    2010-05-15

    VX (O-ethyl-S-[2(di-isopropylamino)ethyl] methylphosphonothiolate) is a low volatility organophosphorus (OP) nerve agent and therefore the most likely route of exposure is via percutaneous absorption. Microdialysis has been used as a tool to study percutaneous poisoning by VX in the anesthetised guinea pig. A liquid chromatography tandem mass spectrometry (LC-MS-MS) method using positive electrospray ionisation (ESI) was used to quantitate VX in microdialysate samples collected from microdialysis probes, implanted into a blood vessel of anesthetised guinea pigs. The method resulted from modification of a LC-MS-MS method previously developed for the analysis of dermal microdialysates. Modification increased the sensitivity of the method, allowing quantitation of the trace levels of VX in blood microdialysates, over the range 0.002-1 ng/ml, with linear calibration. Quantitative results have been used to determine the time course of VX concentrations in the blood of guinea pigs following percutaneous poisoning.

  3. [The red blood system in men during long-term head-down bed rest].

    PubMed

    Ivanova, S M; Morukov, B V; Iarlykova, Iu V; Labetskaia, O I; Levina, A A; Kozinets, G I

    2005-01-01

    Red blood was analyzed in six 25 to 40 yr. old male volunteers in a 120-d head-down bedrest (HDBR) study. The hematological investigation included morphological analyses (erythrocyte count and hemoglobin), and determination of iron turnover, erythrocyte IgA, IgG and IgM, metabolism, lipids and phospholipids, and lipid peroxidation rate (LPO). At the beginning of HDBR (day 7), the erythrocyte count and hemoglobin content were found increased w/o any visible changes in the other parameters. Further exposure to HDBR (days 50-100) resulted in modification of intracellular metabolism in erythrocytes, increases in serum iron, and serum and erythrocyte ferritin. On HDBR days 50 and 100, and post-HDBR day 9, cholesterol was increased, LPO intensified and antioxidant activities inhibited, which suggested destabilization of the cell membrane. Hematological shifts in the bedrested volunteers were of the type and pattern similar to those in cosmonauts who fulfilled extended space missions.

  4. Three-dimensional Optical Coherence Tomography Imaging and Treatment of Glaucomatous Optic Nerve Head Defects Associated with Schisis-like Maculopathy

    PubMed Central

    Öztaş, Zafer; Menteş, Jale; Ateş, Halil; Nalçacı, Serhad

    2017-01-01

    We present the three-dimensional (3D) spectral-domain optical coherence tomography (SD-OCT) findings of schisis-like maculopathy associated with structural changes of the optic nerve (ON) head as well as the treatment outcomes of a case of advanced glaucoma. In addition to ophthalmological examination, B-scan and 3D-SD-OCT images of the ON head, peripapillary retina, and the macula were obtained. The B-scan images only detected typical retinoschisis findings. However, the 3D-SD-OCT images of the ON head revealed defects of various sizes, shapes, and depths at the outer wall of the prelaminar and laminar regions of the ON canal. The 3D images were able to establish that these defects were both adjacent to and interconnected with the retinal layers. The patient successfully received 3D-SD-OCT-guided thermal laser treatment that is used in congenital optic disc pits complicated with macular schisis. In brief, 3D-SD-OCT is very useful for demonstrating the ON head defects that can lead to schisis-like maculopathy in cases of advanced glaucoma.

  5. Emotional stress induced by parachute jumping enhances blood nerve growth factor levels and the distribution of nerve growth factor receptors in lymphocytes.

    PubMed

    Aloe, L; Bracci-Laudiero, L; Alleva, E; Lambiase, A; Micera, A; Tirassa, P

    1994-10-25

    We examined the plasma nerve growth factor (NGF) level and the distribution of NGF receptors in peripheral lymphocytes of young soldiers (mean age, 20-24 yr) experiencing the thrill of a novice about to make their first parachute jumps. Blood was collected from soldiers who knew they were selected to jump (n = 26), as well as from soldiers who knew they were not selected (n = 17, controls). The former group was sampled the evening before the jump and 20 min after landing. Compared with controls, NGF levels increased 84% in prejump and 107% in postjump sampling. Our studies also showed that the increase of NGF levels preceded the increase of plasma cortisol and adrenocorticotropic hormone. No changes in the baseline levels of circulating interleukin 1 beta or tumor necrosis factor were found, suggesting that the increased levels of NGF were not correlated with change in these cytokines. Moreover, immunofluorescence analysis demonstrated that parachuting stress enhances the distribution of low-affinity p75LNGFR and high-affinity p140trkA NGF receptors in circulating peripheral blood mononuclear cells. These observations suggest that the release of NGF might be involved in the activation of cells of the immune system and is most probably associated with homeostatic adaptive mechanisms, as previously shown for stressed rodents.

  6. Emotional stress induced by parachute jumping enhances blood nerve growth factor levels and the distribution of nerve growth factor receptors in lymphocytes.

    PubMed Central

    Aloe, L; Bracci-Laudiero, L; Alleva, E; Lambiase, A; Micera, A; Tirassa, P

    1994-01-01

    We examined the plasma nerve growth factor (NGF) level and the distribution of NGF receptors in peripheral lymphocytes of young soldiers (mean age, 20-24 yr) experiencing the thrill of a novice about to make their first parachute jumps. Blood was collected from soldiers who knew they were selected to jump (n = 26), as well as from soldiers who knew they were not selected (n = 17, controls). The former group was sampled the evening before the jump and 20 min after landing. Compared with controls, NGF levels increased 84% in prejump and 107% in postjump sampling. Our studies also showed that the increase of NGF levels preceded the increase of plasma cortisol and adrenocorticotropic hormone. No changes in the baseline levels of circulating interleukin 1 beta or tumor necrosis factor were found, suggesting that the increased levels of NGF were not correlated with change in these cytokines. Moreover, immunofluorescence analysis demonstrated that parachuting stress enhances the distribution of low-affinity p75LNGFR and high-affinity p140trkA NGF receptors in circulating peripheral blood mononuclear cells. These observations suggest that the release of NGF might be involved in the activation of cells of the immune system and is most probably associated with homeostatic adaptive mechanisms, as previously shown for stressed rodents. Images PMID:7937971

  7. Effects of evening primrose oil treatment on sciatic nerve blood flow and endoneurial oxygen tension in streptozotocin-diabetic rats.

    PubMed

    Cameron, N E; Cotter, M A

    1994-12-01

    Evening primrose oil (EPO) is rich in the omega-6 essential fatty acid component, gamma-linolenic acid. The aim of the investigation was to determine whether EPO treatment prevented a reduction in sciatic nerve perfusion and oxygenation in streptozotocin-diabetic rats. Rats were treated from diabetes induction with 10 g EPO kg-1 day-1. Sciatic blood flow was measured by microelectrode polarography and hydrogen clearance. Diabetes caused 47.7% +/- 3.4% (P < 0.001) and 58.8% +/- 4.8% (P < 0.001) reduction in the nutritive (capillary) and the non-nutritive (large vessel) components of endoneurial blood flow, respectively, which were prevented by EPO. Treatment had no significant effect on nutritive flow in non-diabetic rats; however, the rate of non-nutritive flow increased by 97.7% +/- 38.9% (P < 0.01). Sciatic endoneurial oxygen tension was measured by microelectrode polarography. Diabetes resulted in a 44.7% +/- 3.4% reduction in mean oxygen tension (P < 0.001), which was largely (82.3% +/- 10.2%) prevented by EPO treatment (P < 0.001). Thus, EPO prevents impairment of blood flow and endoneurial oxygenation in experimental diabetes. It is likely that this neurovascular action accounts for the beneficial effects of treatment on nerve function in diabetic rats and patients.

  8. Time-Dependent Impact of Irreversible Electroporation on Pancreas, Liver, Blood Vessels and Nerves: A Systematic Review of Experimental Studies

    PubMed Central

    Agnass, P.; Crezee, J.; Dijk, F.; Verheij, J.; van Gulik, T. M.; Meijerink, M. R.; Vroomen, L. G.; van Lienden, K. P.; Besselink, M. G.

    2016-01-01

    Introduction Irreversible electroporation (IRE) is a novel ablation technique in the treatment of unresectable cancer. The non-thermal mechanism is thought to cause mostly apoptosis compared to necrosis in thermal techniques. Both in experimental and clinical studies, a waiting time between ablation and tissue or imaging analysis to allow for cell death through apoptosis, is often reported. However, the dynamics of the IRE effect over time remain unknown. Therefore, this study aims to summarize these effects in relation to the time between treatment and evaluation. Methods A systematic search was performed in Pubmed, Embase and the Cochrane Library for original articles using IRE on pancreas, liver or surrounding structures in animal or human studies. Data on pathology and time between IRE and evaluation were extracted. Results Of 2602 screened studies, 36 could be included, regarding IRE in liver (n = 24), pancreas (n = 4), blood vessels (n = 4) and nerves (n = 4) in over 440 animals (pig, rat, goat and rabbit). No eligible human studies were found. In liver and pancreas, the first signs of apoptosis and haemorrhage were observed 1–2 hours after treatment, and remained visible until 24 hours in liver and 7 days in pancreas after which the damaged tissue was replaced by fibrosis. In solitary blood vessels, the tunica media, intima and lumen remained unchanged for 24 hours. After 7 days, inflammation, fibrosis and loss of smooth muscle cells were demonstrated, which persisted until 35 days. In nerves, the median time until demonstrable histological changes was 7 days. Conclusions Tissue damage after IRE is a dynamic process with remarkable time differences between tissues in animals. Whereas pancreas and liver showed the first damages after 1–2 hours, this took 24 hours in blood vessels and 7 days in nerves. PMID:27870918

  9. Effect of selective vagal nerve stimulation on blood pressure, heart rate and respiratory rate in rats under metoprolol medication.

    PubMed

    Gierthmuehlen, Mortimer; Plachta, Dennis T T

    2016-02-01

    Selective vagal nerve stimulation (sVNS) has been shown to reduce blood pressure without major side effects in rats. This technology might be the key to non-medical antihypertensive treatment in patients with therapy-resistant hypertension. β-blockers are the first-line therapy of hypertension and have in general a bradycardic effect. As VNS itself can also promote bradycardia, it was the aim of this study to investigate the influence of the β1-selective blocker Metoprolol on the effect of sVNS especially with respect to the heart rate. In 10 male Wistar rats, a polyimide multichannel-cuff electrode was placed around the vagal nerve bundle to selectively stimulate the aortic depressor nerve fibers. The stimulation parameters were adapted to the thresholds of individual animals and were in the following ranges: frequency 30-50 Hz, amplitude 0.3-1.8 mA and pulse width 0.3-1.3 ms. Blood pressure responses were detected with a microtip transducer in the carotid artery, and electrocardiography was recorded with s.c. chest electrodes. After IV administration of Metoprolol (2 mg kg(-1) body weight), the animals' mean arterial blood pressure (MAP) and heart rate (HR) decreased significantly. Although the selective electrical stimulation of the baroreceptive fibers reduced MAP and HR, both effects were significantly alleviated by Metoprolol. As a side effect, the rate of stimulation-induced apnea significantly increased after Metoprolol administration. sVNS can lower the MAP under Metoprolol without causing severe bradycardia.

  10. Facial nerve paralysis and partial brachial plexopathy after epidural blood patch: a case report and review of the literature

    PubMed Central

    Shahien, Radi; Bowirrat, Abdalla

    2011-01-01

    We report a complication related to epidural analgesia for delivery in a 24- year-old woman who was admitted with mild pre-eclampsia and for induction of labor. At the first postpartum day she developed a postdural puncture headache, which was unresponsive to conservative measures. On the fifth day an epidural blood patch was done, and her headache subsided. Sixteen hours later she developed paralysis of the right facial nerve, which was treated with prednisone. Seven days later she complained of pain in the left arm and the posterior region of the shoulder. She was later admitted and diagnosed with partial brachial plexopathy. PMID:21386953

  11. Estimation of the neuromotor system functional state after sciatic nerve neurorrhaphy in experimental conditions of intravenous laser irradiation of blood

    NASA Astrophysics Data System (ADS)

    Nechipurenko, N. I.; Tanin, Leonid V.; Antonov, Ignatii P.; Vasilevskaya, Lyudmila A.; Vlasyuk, P. A.

    1996-12-01

    The speckle-optical methods and the methods of electroneuromyography were used to study the myotonus, the contractional activity of leg muscles and the neuromotor system functional state in intact rabbits and 3 months after the sciatic nerve (SN) neurorrhaphy in conditions of intravenous laser irradiation of blood (ILIB). The blood of animals was exposed to laser radiation with the help of a quartz-polymeric light guide, which has been inserted into the earvein the next day after SN stitching. The radiation power at the light guide output was 2-2.5 mW. Two courses of treatment with a two-week interval have been conducted. It has been established from the speckle-optical study data that ILIB increases the contractional activity of skeletal muscles in animals. The ILIB-therapy after the SN neurorrhaphy normalizes the latent period of M-response and neural cation potential. A tendancy has been revealed to an increase in impulse conduction velocity in motor nerve fibers and in maximal amplitude of the neural action potential. Thus, the ILIB-therapy after SN trauma improves the neuromotor system functional state in experimental animals in the early reinnervation period.

  12. Modeling leukocyte trafficking at the human blood-nerve barrier in vitro and in vivo geared towards targeted molecular therapies for peripheral neuroinflammation.

    PubMed

    Greathouse, Kelsey M; Palladino, Steven P; Dong, Chaoling; Helton, Eric S; Ubogu, Eroboghene E

    2016-01-06

    Peripheral neuroinflammation is characterized by hematogenous mononuclear leukocyte infiltration into peripheral nerves. Despite significant clinical knowledge, advancements in molecular biology and progress in developing specific drugs for inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis, there are currently no specific therapies that modulate pathogenic peripheral nerve inflammation. Modeling leukocyte trafficking at the blood-nerve barrier using a reliable human in vitro model and potential intravital microscopy techniques in representative animal models guided by human observational data should facilitate the targeted modulation of the complex inflammatory cascade needed to develop safe and efficacious therapeutics for immune-mediated neuropathies and chronic neuropathic pain.

  13. Optic nerve head topography and retinal structural changes in eyes with macrodisks: a comparative study with spectral domain optical coherence tomography

    PubMed Central

    Öztürker, Zeynep Kayaarası; Eltutar, Kadir; Karini, Belma; Erkul, Sezin Özdogan; Osmanbaşoğlu, Özen Ayrancı; Sultan, Pınar

    2016-01-01

    Purpose To compare optic nerve head parameters, the thicknesses of the peripapillary retinal nerve fiber layer (pRNFL), the macular retinal nerve fiber layer (mRNFL), the ganglion cell complex (GCC), and the ganglion cell–inner plexiform layer (GCIPL) in macrodisks and normal-sized healthy disks using spectral domain optical coherence tomography. Patients and methods A total of 88 healthy eyes (42 macrodisks and 46 normal-sized disks) were prospectively enrolled in the study. Optic nerve head parameters as well as pRNFL, mRNFL, GCC, and GCIPL thicknesses were measured in all subjects. Optic disk areas (ODAs) >2.70 mm2 were defined as macrodisks. All spectral domain optical coherence tomography parameters were compared between normal-sized disks and macrodisks. Results The mean age of the participants was 49.4±5.7 years in the normal size group and 51.55±6.3 years in the macrodisk group (P=0.65). The average ODAs were 2.23±0.29 mm2 and 3.30±0.59 mm2 in the normal size and the macrodisk groups, respectively. ODA (P<0.001), cup area (P<0.001), cup disk area ratio (P<0.001), horizontal cup disk ratio (P<0.001), vertical cup disk ratio (P<0.001), horizontal disk diameter (P<0.001), vertical disk diameter (P<0.001), and cup volume (P<0.001) were significantly higher in the macrodisk group. The inferior mRNFL thickness was significantly lower (P=0.042), and the GCC inferior and GCIPL inferior thicknesses were found to be lower with low significance (P=0.052, P=0.059, respectively) in the macrodisk group. Rim volume (P=0.622), total pRNFL (P=0.201), superior pRNFL (P=0.123), inferior pRNFL (P=0.168), average macular thickness (P=0.162), total mRNFL (P=0.171), superior mRNFL (P=0.356), total GCC (P=0.080), superior GCC (P=0.261), total GCIPL (P=0.214), and superior GCIPL (P=0.515) thicknesses were similar in both groups. Conclusion Optic disk topography and retinal structures show different characteristics in healthy eyes with macrodisks. These disk size

  14. Size of the Optic Nerve Head and Its Relationship with the Thickness of the Macular Ganglion Cell Complex and Peripapillary Retinal Nerve Fiber Layer in Patients with Primary Open Angle Glaucoma

    PubMed Central

    Enomoto, Nobuko; Anraku, Ayako; Ishida, Kyoko; Takeyama, Asuka; Yagi, Fumihiko; Tomita, Goji

    2015-01-01

    Purpose. To evaluate the relationships among the optic nerve head (ONH) area, macular ganglion cell complex (mGCC) thickness, circumpapillary retinal nerve fiber layer (cpRNFL) thickness, and visual field defects in patients with primary open angle glaucoma (POAG). Methods. This retrospective study included 90 eyes of 90 patients with POAG. The ONH area, rim area, mGCC thickness, and cpRNFL thickness were measured using optical coherence tomography. Mean deviation (MD) was measured using standard automated perimetry. The relationships among clinical factors including age, refraction, the ONH area, the rim area, the mGCC thickness, the cpRNFL thickness, and MD were evaluated using correlation coefficients and multiple regression analyses. Results. The significant correlation of the ONH area with refraction (r = 0.362, P < 0.001), the mGCC thickness (r = 0.225, P = 0.033), and the cpRNFL thickness (r = 0.253, P = 0.016) was found. Multiple regression analysis showed that the ONH area, rim area, and MD were selected as significant contributing factors to explain the mGCC thickness and cpRNFL thickness. No factor was selected to explain MD. Conclusions. The ONH area, in other words, the disc size itself may affect the mGCC thickness and cpRNFL thickness in POAG patients. PMID:26339503

  15. [ROLE OF CAPSAICIN-SENSITIVE NERVES IN THE REGULATION OF DEHYDROEPIANDROSTERONE SULFATE BLOOD CONTENT UNDER NORMAL AND FRUCTOSE-INDUCED METABOLIC SYNDROME].

    PubMed

    Spiridonov, V K; Tolochko, Z S; Ovcjukova, M V; Kostina, N E; Obut, T A

    2015-08-01

    The effects of the stimulation of capsaicin-sensitive nerves (capsaicin, 1 mg/kg, s/c) and their eafferentation (capsaicin, 150 mg/kg, s/c) on the blood content of dehydroepiandrosterone sulfate (DHEAS) was investigated in normal rats and rats with fructose-induced metabolic syndrome (12.5% fructose solution, 10 weeks). An increase in blood of tryglyceride, lipid peroxidation, glucose (fasting and after loading glucose, 2 mg/kg, i/p) was considered as symptoms of metabolic syndrome. It was shown that in normal rats drinking tap water the stimulation of capsaicin-sensitive nerves resulted in the increase of DHEAS content while their deafferentation reduced the concentration of this hormone in the blood. The fructose diet caused the decrease in content of DHEAS, triglyceridemia, lipid peroxidation, impaired tolerance glucose. In rats with the metabolic syndrome the stimulation capsaicin-sensitive nerves prevented the fructose-induced decrease of DHEAS content as well as decreased the symptoms of metabolic syndrome. In fructose fed rats the stimulation-induced effects were prevented by the deafferentation of capsaicin-sensitive nerves. It is suggested that capsaicin-sensitive nerves contribute both to the regulation of blood content of DHEAS under normal and fructose-induced metabolic syndrome.

  16. Spatiotemporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shanbin; Cheng, Haiying; Zeng, Shaoqun

    2003-07-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%) 2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  17. Enhanced Stability of Blood Matrices Using a Dried Sample Spot Assay to Measure Human Butyrylcholinesterase Activity and Nerve Agent Adducts

    PubMed Central

    Perez, Jonas W.; Pantazides, Brooke G.; Watson, Caroline M.; Thomas, Jerry D.; Blake, Thomas A.; Johnson, Rudolph C.

    2015-01-01

    Dried matrix spots are safer to handle and easier to store than wet blood products, but factors such as intra-spot variability and unknown sample volumes have limited their appeal as a sampling format for quantitative analyses. In this work, we introduce a dried spot activity assay for quantifying butyrylcholinesterase (BChE) specific activity which is BChE activity normalized to the total protein content in a sample spot. The method was demonstrated with blood, serum, and plasma spotted on specimen collection devices (cards) which were extracted to measure total protein and BChE activity using a modified Ellman assay. Activity recovered from dried spots was ∼80% of the initial spotted activity for blood and >90% for plasma and serum. Measuring total protein in the sample and calculating specific activity substantially improved quantification and reduced intra-spot variability. Analyte stability of nerve agent adducts was also evaluated, and the results obtained via BChE-specific activity measurements were confirmed by quantification of BChE adducts using a previously established LC-MS/MS method. The spotted samples were up to 10-times more resistant to degradation compared to unspotted control samples when measuring BChE inhibition by the nerve agents sarin and VX. Using this method, both BChE activity and adducts can be accurately measured from a dried sample spot. This use of a dried sample spot with normalization to total protein is robust, demonstrates decreased intra-spot variability without the need to control for initial sample volume, and enhances analyte stability. PMID:25955132

  18. Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps

    PubMed Central

    Huang, Chong; Radabaugh, Jeffrey P.; Aouad, Rony K.; Lin, Yu; Gal, Thomas J.; Patel, Amit B.; Valentino, Joseph; Shang, Yu; Yu, Guoqiang

    2015-01-01

    Abstract. Knowledge of tissue blood flow (BF) changes after free tissue transfer may enable surgeons to predict the failure of flap thrombosis at an early stage. This study used our recently developed noncontact diffuse correlation spectroscopy to monitor dynamic BF changes in free flaps without getting in contact with the targeted tissue. Eight free flaps were elevated in patients with head and neck cancer; one of the flaps failed. Multiple BF measurements probing the transferred tissue were performed during and post the surgical operation. Postoperative BF values were normalized to the intraoperative baselines (assigning “1”) for the calculation of relative BF change (rBF). The rBF changes over the seven successful flaps were 1.89±0.15, 2.26±0.13, and 2.43±0.13 (mean±standard error), respectively, on postoperative days 2, 4, and 7. These postoperative values were significantly higher than the intraoperative baseline values (p<0.001), indicating a gradual recovery of flap vascularity after the tissue transfer. By contrast, rBF changes observed from the unsuccessful flaps were 1.14 and 1.34, respectively, on postoperative days 2 and 4, indicating less flow recovery. Measurement of BF recovery after flap anastomosis holds the potential to act early to salvage ischemic flaps. PMID:26187444

  19. Altered Blood Biomarker Profiles in Athletes with a History of Repetitive Head Impacts

    PubMed Central

    2016-01-01

    The long-term health effects of concussion and sub-concussive impacts in sport are unknown. Growing evidence suggests both inflammation and neurodegeneration are pivotal to secondary injury processes and the etiology of neurodegenerative diseases. In the present study we characterized circulating brain injury and inflammatory mediators in healthy male and female athletes according to concussion history and collision sport participation. Eighty-seven university level athletes (male, n = 60; female, n = 27) were recruited before the start of the competitive season. Athletes were healthy at the time of the study (no medications, illness, concussion or musculoskeletal injuries). Dependent variables included 29 inflammatory and 10 neurological injury analytes assessed in the peripheral blood by immunoassay. Biomarkers were statistically evaluated using partial least squares multivariate analysis to identify possible relationships to self-reported previous concussion history, number of previous concussions and collision sport participation in male and female athletes. Multiple concussions were associated with increases in peripheral MCP-1 in females, and MCP-4 in males. Collision sport participation was associated with increases in tau levels in males. These results are consistent with previous experimental and clinical findings that suggest ongoing inflammatory and cerebral injury processes after repetitive mild head trauma. However, further validation is needed to correlate systemic biomarkers to repetitive brain impacts, as opposed to the extracranial effects common to an athletic population such as exercise and muscle damage. PMID:27458972

  20. Cerebral blood flow velocity in humans exposed to 24 h of head-down tilt

    NASA Technical Reports Server (NTRS)

    Kawai, Y.; Murthy, G.; Watenpaugh, D. E.; Breit, G. A.; Deroshia, C. W.; Hargens, A. R.

    1993-01-01

    This study investigates cerebral blood flow (CBF) velocity in humans before, during, and after 24 h of 6 deg head-down tilt (HDT), which is a currently accepted experimental model to simulate microgravity. CBF velocity was measured by use of the transcranial Doppler technique in the right middle cerebral artery of eight healthy male subjects. Mean CBF velocity increased from the pre-HDT upright seated baseline value of 55.5 +/- 3.7 (SE) cm/s to 61.5 +/- 3.3 cm/s at 0.5 h of HDT, reached a peak value of 63.2 +/- 4.1 cm/s at 3 h of HDT, and remained significantly above the pre-HDT baseline for over 6 h of HDT. During upright seated recovery, mean CBF velocity decreased to 87 percent of the pre-HDT baseline value. Mean CBF velocity correlated well with calculated intracranial arterial pressure (IAP). As analyzed by linear regression, mean CBF velocity = 29.6 + 0.32IAP. These results suggest that HDT increases CBF velocity by increasing IAP during several hours after the onset of microgravity. Importantly, the decrease in CBF velocity after HDT may be responsible, in part, for the increased risk of syncope observed in subjects after prolonged bed rest and also in astronauts returning to Earth.

  1. Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps

    NASA Astrophysics Data System (ADS)

    Huang, Chong; Radabaugh, Jeffrey P.; Aouad, Rony K.; Lin, Yu; Gal, Thomas J.; Patel, Amit B.; Valentino, Joseph; Shang, Yu; Yu, Guoqiang

    2015-07-01

    Knowledge of tissue blood flow (BF) changes after free tissue transfer may enable surgeons to predict the failure of flap thrombosis at an early stage. This study used our recently developed noncontact diffuse correlation spectroscopy to monitor dynamic BF changes in free flaps without getting in contact with the targeted tissue. Eight free flaps were elevated in patients with head and neck cancer; one of the flaps failed. Multiple BF measurements probing the transferred tissue were performed during and post the surgical operation. Postoperative BF values were normalized to the intraoperative baselines (assigning "1") for the calculation of relative BF change (rBF). The rBF changes over the seven successful flaps were 1.89±0.15, 2.26±0.13, and 2.43±0.13 (mean±standard error), respectively, on postoperative days 2, 4, and 7. These postoperative values were significantly higher than the intraoperative baseline values (p<0.001), indicating a gradual recovery of flap vascularity after the tissue transfer. By contrast, rBF changes observed from the unsuccessful flaps were 1.14 and 1.34, respectively, on postoperative days 2 and 4, indicating less flow recovery. Measurement of BF recovery after flap anastomosis holds the potential to act early to salvage ischemic flaps.

  2. Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps.

    PubMed

    Huang, Chong; Radabaugh, Jeffrey P; Aouad, Rony K; Lin, Yu; Gal, Thomas J; Patel, Amit B; Valentino, Joseph; Shang, Yu; Yu, Guoqiang

    2015-07-01

    Knowledge of tissue blood flow (BF) changes after free tissue transfer may enable surgeons to predict the failure of flap thrombosis at an early stage. This study used our recently developed noncontact diffuse correlation spectroscopy to monitor dynamic BF changes in free flaps without getting in contact with the targeted tissue. Eight free flaps were elevated in patients with head and neck cancer; one of the flaps failed. Multiple BF measurements probing the transferred tissue were performed during and post the surgical operation. Postoperative BF values were normalized to the intraoperative baselines (assigning "1") for the calculation of relative BF change (rBF). The rBF changes over the seven successful flaps were 1.89 ± 0.15, 2.26 ± 0.13, and 2.43 ± 0.13 (mean ± standard error), respectively, on postoperative days 2, 4, and 7. These postoperative values were significantly higher than the intraoperative baseline values (p<0.001), indicating a gradual recovery of flap vascularity after the tissue transfer. By contrast, rBF changes observed from the unsuccessful flaps were 1.14 and 1.34, respectively, on postoperative days 2 and 4, indicating less flow recovery. Measurement of BF recovery after flap anastomosis holds the potential to act early to salvage ischemic flaps.

  3. Comparative survival study of glial cells and cells composing walls of blood vessels in crustacean ventral nerve cord after photodynamic treatment

    NASA Astrophysics Data System (ADS)

    Kolosov, Mikhail S.; Shubina, Elena

    2015-03-01

    Photodynamic therapy is a prospective treatment modality of brain cancers. It is of importance to have information about relative survival rate of different cell types in nerve tissue during photodynamic treatment. Particularly, for development of sparing strategy of the photodynamic therapy of brain tumors, which pursuits both total elimination of malignant cells, which are usually of glial origin, and, at the same time, preservation of normal blood circulation as well as normal glial cells in the brain. The aim of this work was to carry out comparative survival study of glial cells and cells composing walls of blood vessels after photodynamic treatment, using simple model object - ventral nerve cord of crustacean.

  4. Head injury. Second edition

    SciTech Connect

    Cooper, P.R.

    1987-01-01

    This book contains 22 chapters. Some of the chapter titles are: Radiographic Evaluation; Epidemiology of Head Injury; Emergency Care and Initial Evaluation; Skull Fracture and Traumatic Cerebrospinal Fluid Fistulas; Mild Head Injury; and Injuries of the Cranial Nerves.

  5. A 10-minute point-of-care assay for detection of blood protein adducts resulting from low level exposure to organophosphate nerve agents.

    PubMed

    VanDine, Robert; Babu, Uma Mahesh; Condon, Peter; Mendez, Arlene; Sambursky, Robert

    2013-03-25

    The OrganoTox test is a rapid, point-of-care assay capable of detecting clinically relevant organophosphate (OP) poisoning after low-level exposure to sarin, soman, tabun, or VX chemical nerve agents. The test utilizes either a finger stick peripheral blood sample or plasma specimen. While high-level nerve agent exposure can quickly lead to death, low-level exposure produces vague, nondescript signs and symptoms that are not easily clinically differentiated from other conditions. In initial testing, the OrganoTox test was used to detect the presence of blood protein-nerve agent adducts in exposed blood samples. In order to mimic the in vivo exposure as closely as possible, nerve agents stored in organic solvents were spiked in minute quantities into whole blood samples. For performance testing, 40 plasma samples were spiked with sarin, soman, tabun, or VX and 10 normal plasma samples were used as the negative control. The 40 nerve agent-spiked plasma samples included 10 replicates of each agent. At the clinically relevant low-level exposure of 10 ng/ml, the OrganoTox test demonstrated 100% sensitivity for soman, tabun, and VX and 80% sensitivity for sarin. The OrganoTox test demonstrated greater than 97% specificity with 150 blood samples obtained from healthy adults. No cross-reactivity or interference from pesticide precursor compounds was found. A rapid test for nerve agent exposure will help identify affected patients earlier in the clinical course and trigger more appropriate medical management in a more timely manner.

  6. Detection of time window of cerebral blood flow response induced by sciatic nerve stimulation using temporal clustering analysis

    NASA Astrophysics Data System (ADS)

    Wang, Zheng; Luo, Qingming; Cheng, Haiying; Zeng, Shaoqun

    2003-07-01

    In many studies on functional neuroimaging, change in local cerebral blood flow (CBF) induced by sensory stimulation is used as a substitutive marker for change in cortical neuronal activity by Roy and Sherrington"s postulation. The purpose of this study is to evaluate the close temporal relationship between evoked local CBF and neuronal activity through utilizing temporal clustering analysis (TCA) method to analyze the dataset obtained by high-resolution laser speckle imaging (LSI). We mapped a relatively large somatosensory area of cerebral cortex in successively and followed variations of cerebral blood flow under sciatic nerve stimulation in anesthetized rats using LSI technique. Then we illustrated TCA method on the optical imaging signals and investigated the temporal characteristics of CBF activation. Contralateral somatosensory cortical microflow was activated to increase promptly in less than 1 second after the onset of 2 seconds electrical stimulation (pulse parameters: 0.5ms, 5Hz, 350mV). The data of the present study may possibly shed light on the development question of functional magnetic resonance imaging (fMRI) whether the ultimate spatial resolution attainable by fMRI is limited by the physiology of the cerebral blood flow response to activation or by the hardware and signal-to-noise ratio.

  7. Fiber-optic immuno-biosensor for rapid and accurate detection of nerve growth factor in human blood.

    PubMed

    Tang, Liang; Cha, Yong-Mei; Li, Hongmei; Chen, Peng-Sheng; Lin, Shien-Fong

    2006-01-01

    An accurate and rapid assay of cardiac nerve growth factor (NGF) levels in blood can provide physicians with critical information regarding myocardial injury and neural remodeling in cardiac tissues to identify patients at risk of impending heart attack, thereby enabling them to receive appropriate lifesaving treatment more quickly. Currently used assay methods, such as enzyme-linked immunosorbent assay (ELISA), are usually time-consuming (hours to days), expensive and technically complicated. In this paper, we described the development and clinical study of a rapid and sensitive method for detection and quantification of NGF in human blood plasma. This method utilizes a fiber-optic, immuno-biosensing system which performs a fluorophore-mediated sandwich immunoassay on the surface of an optical fiber. Physiological concentrations of NGF could be quantified in both buffer and human blood plasma samples within 5 minutes. The NGF concentrations determined by the fiberoptic sensor were comparable to those by the gold standard, ELISA. Preliminary study of NGF assay in cardiac patient plasma samples showed a great potential of the fiber-optic sensor as a rapid diagnostic and prognostic tool in clinical applications.

  8. Characterization of cerebral blood flow response to sciatic nerve stimulation using laser speckle imaging

    NASA Astrophysics Data System (ADS)

    Wang, Zheng; Luo, Qingming; Cheng, Haiying; Lu, Qiang

    2003-12-01

    Laser speckle imaging (LSI) through a thinned skull over the somatosensory cortex was utilized to map the spatiotemporal characteristics of local cerebral flood flow (CBF) in anesthetized rats during sciatic nerve stimulation. Region-of-interest selection and Temporal clustering analysis (TCA) method was illustrated on the dataset from high-resolution optical imaging to detect the timing and location of CBF activation. Contralateral hindlimb sensory cortical microflow was activated to increase promptly in less than 1 s after the onset of 2 s electrical stimulation then evolved in different discrete regions. Individual arteries, veins and capillaries in different diameters were activated with the time going. This pattern is similar but slightly elaborated to the results obtained from laser Doppler flowmetry (LDF), functional magnetic resonance imaging (fMRI). We presented this combination to characterize the behaviors of CBF response to neuronal activity, which might possibly lead to a better understanding of neurovascular coupling and fMRI signals.

  9. Difference in intraosseous blood vessel volume and number in osteoporotic model mice induced by spinal cord injury and sciatic nerve resection.

    PubMed

    Ding, Wen-Ge; Yan, Wei-hong; Wei, Zhao-Xiang; Liu, Jin-Bo

    2012-07-01

    In the present study, we examined intraosseous blood vessel parameters of the tibial metaphysis in mice using microcomputed tomography (µCT) to investigate the relationship between post-nerve-injury osteoporosis and local intraosseous blood vessel volume and number. Mice were randomly divided into groups receiving spinal cord injury (SCI), sciatic nerve resection group (NX), or intact controls (30 mice/group). Four weeks after surgery, mice were perfused with silicone and the distribution of intraosseous blood vessels analyzed by μCT. The bone density, μCT microstructure, biomechanical properties, and the immunohistochemical and biochemical indicators of angiogenesis were also measured. The SCI group showed significantly reduced tibial metaphysis bone density, μCT bone microstructure, tibial biomechanical properties, indicators of angiogenesis, and intraosseous blood vessel parameters compared to the NX group. Furthermore, the spinal cord-injured mice exhibited significantly decreased intraosseous blood vessel volume and number during the development of osteoporosis. In conclusion, these data suggest that decreased intraosseous blood vessel volume and number may play an important role in the development of post-nerve-injury osteoporosis.

  10. Study on the Dynamic Compound Structure Composed of Mast Cells, Blood Vessels, and Nerves in Rat Acupoint

    PubMed Central

    Mingfu, Luo; Xiaotong, Dong; Xiaojing, Song; Jin, Jiang; Jinling, Zhann; Ying, Han

    2013-01-01

    Background. Circulation system, immunity system, and nervous system have a close relationship with meridian phenomen. However, there is still lack of the results of dynamic changes of these structures in acupoint. The aim of this study is to explore the interrelationship by composite staining techniques. Methodology/Principal Findings. Twenty rats were separated into electroacupuncture group (EA) and control group (Con) randomly. In EA group, the Zusanli and Weishu were stimulated with the 0.1 mA for 25 min. The tissue of these acupoints was double-stained with acetylcholinesterase and Toluidine blue. The compound structure of mast cells, nervous fibers, and mast cells in the acupoint was observed. Conclusions/Significance. The blood vessels, mast cells and acetylcholinesterase responded nerves were clearly observed in acupoint tissues. EA can result in the mast cell recruitment and migration along the blood vessels and nervous bundle, which conformed the dynamic compound structure and played important roles in acupuncture. PMID:23878591

  11. Countercurrent transfer of dopamine from venous blood in the cavernous sinus to the arterial blood supplying the brain - the perfused rabbit head as an experimental model.

    PubMed

    Muszak, J; Krzymowski, T; Gilun, P; Stefanczyk-Krzymowska, S

    2014-10-01

    The objective of the current study was to check whether countercurrent transfer of dopamine occurs in the cavernous sinus of the rabbit and whether the rabbit can be used as an animal model to study cavernous sinus function. After exsanguination of the animal, oxygenated and warmed (37°C) Hanseneleit-Krebs buffer with autologous or homologous blood (in a 3:1 or 1:1 ratio) was pumped through both common carotid arteries into the head (60 ml/min; 80-100 mm Hg) and radiolabeled dopamine (3(H)-DA, 10 μCi) was infused into the cavernous sinus through the angular oculi vein. Cerebral blood from the basilar artery was collected from the cannulated vertebral artery during 3(H)-DA infusion and for 10 minutes after completion of infusion. Selected brain tissue samples were collected after completion of the head perfusion. It was demonstrated that dopamine can penetrate from the rabbit's cavernous sinus to the internal carotid artery supplying the brain. Dopamine permeation was greater when the rabbit head was perfused with buffer and blood in a 3:1 ratio than with 1:1 (P<0.01). When the head was perfused with buffer and blood in a 3:1 ratio, significant radioactivity was found in samples collected from the brain basilar artery during and after 3(H)-DA infusion (P<0.001). The radioactivity was identified as 34.13 ± 2.7% unmetabolized 3(H)-DA and 65.9 ± 2.7% its metabolites. Significant radioactivity was also found in some brain tissue samples in both groups (P<0.05). The concentration of free radiolabeled dopamine particles in the dialysate of blood plasma and plasma diluted with buffer did not differ significantly. Because the structures of the cavernous sinus and cavernous fragment of the internal carotid artery of the rabbit are similar to those in humans, it suggests that rabbits can serve as a model for experimental physiological studies of cavernous sinus function and retrograde dopamine transfer in the cavernous sinus should be considered as an important link in

  12. VEGF-A165 potently induces human blood-nerve barrier endothelial cell proliferation, angiogenesis and wound healing in vitro

    PubMed Central

    Reddy, Chetan Lakshmana; Yosef, Nejla; Ubogu, Eroboghene E.

    2013-01-01

    Several mitogens such as vascular endothelial growth factor (VEGF) have been implicated in mammalian vascular proliferation and repair. However, the molecular mediators of human blood-nerve barrier (BNB) development and specialization are unknown. Primary human endoneurial endothelial cells (pHEndECs) were expanded in vitro and specific mitogen receptors detected by western blot. pHEndECs were cultured with basal medium containing different mitogen concentrations with or without heparin. Non-radioactive cell proliferation, Matrigel™-induced angiogenesis and sterile micropipette injury wound healing assays were performed. Proliferation rates, number and total length of induced microvessels and rate of endothelial cell monolayer wound healing were determined and compared to basal conditions. VEGF-A165 in the presence of heparin, was the most potent inducer of pHEndEC proliferation, angiogenesis and wound healing in vitro. 1.31 nM VEGF-A165 induced ~110% increase in cell proliferation relative to basal conditions (~51% without heparin). 2.62 pM VEGF-A165 induced a 3-fold increase in mean number of microvessels and 3.9-fold increase in total capillary length/field relative to basal conditions. In addition, 0.26 nM VEGF-A165 induced ~1.3-fold increased average rate of endothelial wound healing 4–18 hours after endothelial monolayer injury, mediated by increased cell migration. VEGF-A165 was the only mitogen capable of complete wound closure, occurring within 30 hours following injury via increased cell proliferation. This study demonstrates that VEGF-A165, in the presence of heparin, is a potent inducer of pHEndEC proliferation, angiogenesis and wound healing in vitro. VEGF-A165 may be an important mitogen necessary for human BNB development and recovery in response to peripheral nerve injury. PMID:23712256

  13. Heart rate and blood pressure response to short-term head-down bed rest: a nonlinear approach.

    PubMed

    Balocchi, R; Di Garbo, A; Michelassi, C; Chillemi, S; Varanini, M; Barbi, M; Legramante, J M; Raimondi, G; Zbilut, J P

    2000-06-01

    Although it is well-known that prolonged exposure to microgravity environment such as in space travel results in derangements of orthostasis, recent evidence suggests that even short-term exposure may have similar effects and parallels such common examples as prolonged bed rest. Whereas spectral analysis of heart rate and systolic blood pressure have been unable to detect changes, we hypothesized that nonlinear indexes may be better able to uncover such perturbations. Eighteen healthy subjects were exposed to 4-hour head-down tilt, and of these, 4 exhibited fainting. Two nonlinear indexes, mutual information and recurrence quantification were used to analyze the data. Only recurrence quantification was able to detect a "decoupling" of heart rate and systolic blood pressure at rest using discriminant analysis (p < 0.05). These results suggest that orthostatic intolerance may be due to a decoupling of heart rate from systolic blood pressure reflexive activity occurring at rest.

  14. Comparison of the effects of evening primrose oil and triglycerides containing gamma-linolenic acid on nerve conduction and blood flow in diabetic rats.

    PubMed

    Dines, K C; Cameron, N E; Cotter, M A

    1995-04-01

    The aim was to ascertain whether the ability of evening primrose oil (EPO) treatment to correct peripheral nerve dysfunction in streptozotocin-diabetic rats depends on a gamma-linolenic acid (GLA)-containing triglyceride constituent, di-linolein mono-gamma-linolenate (DLMG). A second objective was to investigate whether the triglyceride conformation of GLA affects efficacy, using tri-gamma-linolenate (TGLA), which is not present in EPO. Third, we examined the actions of these omega-6 essential fatty acid-containing oils on sciatic nerve blood flow to establish a common mechanism. After 6 weeks of diabetes, sciatic motor nerve conduction velocity (NCV) was 21% reduced. EPO treatment caused dose-dependent increases in NCV that reached asymptote within 7 days. DLMG and TGLA, at doses matched for GLA content, had effects indistinguishable from those of EPO. Sciatic blood flow, 47.2% reduced by diabetes, was partially normalized by EPO, DLMG and TGLA. In contrast, sunflower oil (which does not contain GLA) did not alter NCV or blood flow. The data therefore provide strong evidence that DLMG is the active component of EPO and suggest that correction of nerve dysfunction involves a vascular action. The precise triglyceride configuration of GLA does not appear crucial to its effects in experimental diabetic neuropathy.

  15. The Effect of Ergotamine on Tissue Blood Flow and the Arteriovenous Shunting of Radioactive Microspheres in the Head

    PubMed Central

    Johnston, Barbara M.; Saxena, P.R.

    1978-01-01

    1 The radioactive microsphere method was used to study the effects of ergotamine (5, 10 and 20 μg/kg, i.v.) on systemic and regional haemodynamic variables in chloralose-urethane anaesthetized cats. The influence of the drug was also studied on the number of 15 μm microspheres escaping entrapment in the head to emerge in the left external jugular vein. 2 Ergotamine decreased the heart rate and cardiac output. Since arterial blood pressure remained unchanged, calculated total peripheral resistance increased. 3 The regional distribution of cardiac output obtained with 15 μm microspheres agreed well with previous studies in cats where 25 μm spheres were used. The most pronounced difference was that in the present investigation more microspheres, apparently escaping through arteriovenous anastomoses (AVAs), were detected in the lungs than when larger spheres had been used. 4 Coronary blood flow decreased, while uterine blood flow was increased by the drug. The microsphere content of the lungs, which receive the spheres not only via bronchial arteries but also via AVAs, was greatly reduced by all doses of ergotamine. Ergotamine did not influence tissue blood flow to other major organs such as the brain, kidneys, skin, liver, skeletal muscle or the gastrointestinal tract. 5 In the 16 experiments, 0.46 ± 0.05 (s.e. mean)% of the total microspheres injected (equivalent to 11.7 ± 1.4% of microspheres detected in the left-side of the head) appeared within 2 min of microsphere injection into the left external jugular vein. The highest dose of ergotamine significantly reduced the shunting of the microspheres in the head. 6 Since 15 μm microspheres are only likely to reach the lungs by passing into the venous circulation through large glomus-type AVAs, we conclude that ergotamine reduces the fraction of microspheres appearing in the lungs by causing strong vasoconstriction in the AVAs in the head. 7 In conformity with the closure of head AVAs is the finding that

  16. Macrophage depletion lowers blood pressure and restores sympathetic nerve α2-adrenergic receptor function in mesenteric arteries of DOCA-salt hypertensive rats

    PubMed Central

    Thang, Loc V.; Demel, Stacie L.; Crawford, Robert; Kaminski, Norbert E.; Swain, Greg M.; Van Rooijen, Nico

    2015-01-01

    We tested the hypothesis that vascular macrophage infiltration and O2− release impairs sympathetic nerve α2-adrenergic autoreceptor (α2AR) function in mesenteric arteries (MAs) of DOCA-salt hypertensive rats. Male rats were uninephrectomized or sham operated (sham). DOCA pellets were implanted subcutaneously in uninephrectomized rats who were provided high-salt drinking water or high-salt water with apocynin. Sham rats received tap water. Blood pressure was measured using radiotelemetry. Treatment of sham and DOCA-salt rats with liposome-encapsulated clodronate was used to deplete macrophages. After 3–5, 10–13, and 18–21 days of DOCA-salt treatment, MAs and peritoneal fluid were harvested from euthanized rats. Norepinephrine (NE) release from periarterial sympathetic nerves was measured in vitro using amperometry with microelectrodes. Macrophage infiltration into MAs as well as TNF-α and p22phox were measured using immunohistochemistry. Peritoneal macrophage activation was measured by flow cytometry. O2− was measured using dihydroethidium staining. Hypertension developed over 28 days, and apocynin reduced blood pressure on days 18–21. O2− and macrophage infiltration were greater in DOCA-salt MAs compared with sham MAs after day 10. Peritoneal macrophage activation occurred after day 10 in DOCA-salt rats. Macrophages expressing TNF-α and p22phox were localized near sympathetic nerves. Impaired α2AR function and increased NE release from sympathetic nerves occurred in MAs from DOCA-salt rats after day 18. Macrophage depletion reduced blood pressure and vascular O2− while restoring α2AR function in DOCA-salt rats. Macrophage infiltration into the vascular adventitia contributes to increased blood pressure in DOCA-salt rats by releasing O2−, which disrupts α2AR function, causing enhanced NE release from sympathetic nerves. PMID:26320034

  17. Diabetes and nerve damage

    MedlinePlus

    Diabetic neuropathy; Diabetes - neuropathy; Diabetes - peripheral neuropathy ... In people with diabetes, the body's nerves can be damaged by decreased blood flow and a high blood sugar level. This condition is ...

  18. Influences of neck afferents on sympathetic and respiratory nerve activity.

    PubMed

    Bolton, P S; Kerman, I A; Woodring, S F; Yates, B J

    1998-11-15

    It is well established that the vestibular system influences the sympathetic nervous system and the respiratory system; presumably, vestibulosympathetic and vestibulorespiratory responses participate in maintaining stable blood pressure and blood oxygenation during movement and changes in posture. Many brainstem neurons that generate vestibulospinal reflexes integrate signals from the labyrinth and neck muscles to distinguish between head movements on a stable body and whole body movements. In the present study, responses were recorded from the splanchnic (sympathetic), hypoglossal (inspiratory) and abdominal (expiratory) nerves during stimulation of the C2 dorsal root ganglion or C2 or C3 nerve branches innervating dorsal neck muscles. Stimulation of neck afferents using low current intensities, in many cases less than twice the threshold for producing an afferent volley recordable from the cord dorsum, elicited changes in sympathetic and respiratory nerve activity. These data suggest that head rotation on a stable body would elicit both cervical and vestibular inputs to respiratory motoneurons and sympathetic preganglionic neurons. The effects of cervical afferent stimulation on abdominal, splanchnic and hypoglossal nerve activity were not abolished by transection of the brainstem caudal to the vestibular nuclei; thus, pathways in addition to those involving the vestibular nuclei are involved in relaying cervical inputs to sympathetic preganglionic neurons and respiratory motoneurons. Transection of the C1-3 dorsal roots enhanced responses of the splanchnic and abdominal nerves to pitch head rotations on a fixed body but diminished responses of the hypoglossal nerve. Thus, neck and vestibular afferent influences on activity of respiratory pump muscles and sympathetic outflow appear to be antagonistic, so that responses will occur during whole body movements but not head movements on a stationary trunk. In contrast, neck and vestibular influences on tongue

  19. Cost-effective instrumentation for quantitative depth measurement of optic nerve head using stereo fundus image pair and image cross correlation techniques

    NASA Astrophysics Data System (ADS)

    de Carvalho, Luis Alberto V.; Carvalho, Valeria

    2014-02-01

    One of the main problems with glaucoma throughout the world is that there are typically no symptoms in the early stages. Many people who have the disease do not know they have it and by the time one finds out, the disease is usually in an advanced stage. Most retinal cameras available in the market today use sophisticated optics and have several other features/capabilities (wide-angle optics, red-free and angiography filters, etc) that make them expensive for the general practice or for screening purposes. Therefore, it is important to develop instrumentation that is fast, effective and economic, in order to reach the mass public in the general eye-care centers. In this work, we have constructed the hardware and software of a cost-effective and non-mydriatic prototype device that allows fast capturing and plotting of high-resolution quantitative 3D images and videos of the optical disc head and neighboring region (30° of field of view). The main application of this device is for glaucoma screening, although it may also be useful for the diagnosis of other pathologies related to the optic nerve.

  20. Determination of cup-to-disc ratio of optical nerve head for diagnosis of glaucoma on stereo retinal fundus image pairs

    NASA Astrophysics Data System (ADS)

    Muramatsu, Chisako; Nakagawa, Toshiaki; Sawada, Akira; Hatanaka, Yuji; Hara, Takeshi; Yamamoto, Tetsuya; Fujita, Hiroshi

    2009-02-01

    A large cup-to-disc (C/D) ratio, which is the ratio of the diameter of the depression (cup) to that of the optical nerve head (ONH, disc), can be one of the important signs for diagnosis of glaucoma. Eighty eyes, including 25 eyes with the signs of glaucoma, were imaged by a stereo retinal fundus camera. An ophthalmologist provided the outlines of cup and disc on a regular monitor and on the stereo display. The depth image of the ONH was created by determining the corresponding pixels in a pair of images based on the correlation coefficient in localized regions. The areas of the disc and cup were determined by use of the red component in one of the color images and by use of the depth image, respectively. The C/D ratio was determined based on the largest vertical lengths in the cup and disc areas, which was then compared with that by the ophthalmologist. The disc areas determined by the computerized method agreed relatively well with those determined by the ophthalmologist, whereas the agreement for the cup areas was somewhat lower. When C/D ratios were employed for distinction between the glaucomatous and non-glaucomatous eyes, the area under the receiver operating characteristic curve (AUC) was 0.83. The computerized analysis of ONH can be useful for diagnosis of glaucoma.

  1. Analysis of the variation in OCT measurements of a structural bottle neck for eye-brain transfer of visual information from 3D-volumes of the optic nerve head, PIMD-Average [02π

    NASA Astrophysics Data System (ADS)

    Söderberg, Per G.; Malmberg, Filip; Sandberg-Melin, Camilla

    2016-03-01

    The present study aimed to analyze the clinical usefulness of the thinnest cross section of the nerve fibers in the optic nerve head averaged over the circumference of the optic nerve head. 3D volumes of the optic nerve head of the same eye was captured at two different visits spaced in time by 1-4 weeks, in 13 subjects diagnosed with early to moderate glaucoma. At each visit 3 volumes containing the optic nerve head were captured independently with a Topcon OCT- 2000 system. In each volume, the average shortest distance between the inner surface of the retina and the central limit of the pigment epithelium around the optic nerve head circumference, PIMD-Average [02π], was determined semiautomatically. The measurements were analyzed with an analysis of variance for estimation of the variance components for subjects, visits, volumes and semi-automatic measurements of PIMD-Average [0;2π]. It was found that the variance for subjects was on the order of five times the variance for visits, and the variance for visits was on the order of 5 times higher than the variance for volumes. The variance for semi-automatic measurements of PIMD-Average [02π] was 3 orders of magnitude lower than the variance for volumes. A 95 % confidence interval for mean PIMD-Average [02π] was estimated to 1.00 +/-0.13 mm (D.f. = 12). The variance estimates indicate that PIMD-Average [02π] is not suitable for comparison between a onetime estimate in a subject and a population reference interval. Cross-sectional independent group comparisons of PIMD-Average [02π] averaged over subjects will require inconveniently large sample sizes. However, cross-sectional independent group comparison of averages of within subject difference between baseline and follow-up can be made with reasonable sample sizes. Assuming a loss rate of 0.1 PIMD-Average [02π] per year and 4 visits per year it was found that approximately 18 months follow up is required before a significant change of PIMDAverage [02π] can

  2. Sympathetic ganglion transcutaneous electrical nerve stimulation after coronary artery bypass graft surgery improves femoral blood flow and exercise tolerance.

    PubMed

    Cipriano, Gerson; Neder, J Alberto; Umpierre, Daniel; Arena, Ross; Vieira, Paulo J C; Chiappa, Adriana M Güntzel; Ribeiro, Jorge P; Chiappa, Gaspar R

    2014-09-15

    We tested the hypothesis that transcutaneous electrical nerve stimulation (TENS) over the stellate ganglion region would reduce sympathetic overstimulation and improve femoral blood flow (FBF) after coronary artery bypass graft surgery. Thirty-eight patients (20 men, 24 New York Heart Association class III-IV) were randomized to 5-day postoperative TENS (n = 20; 4 times/day; 30 min/session) or sham TENS (n = 18) applied to the posterior cervical region (C7-T4). Sympathetic nervous system was stimulated by the cold pressor test, with FBF being measured by ultrasound Doppler. Femoral vascular conductance (FVC) was calculated as FBF/mean arterial pressure (MAP). Six-min walking distance established patients' functional capacity. Before and after the intervention periods, pain scores, opiate requirements, and circulating β-endorphin levels were determined. As expected, preoperative MAP increased and FBF and FVC decreased during the cold pressor test. Sham TENS had no significant effect on these variables (P > 0.05). In contrast, MAP decreased in the TENS group (125 ± 12 vs. 112 ± 10 mmHg). This finding, in association with a consistent increase in FBF (95 ± 5 vs. 145 ± 14 ml/min), led to significant improvements in FVC (P < 0.01). Moreover, 6-min walking distance improved only with TENS (postsurgery-presurgery = 35 ± 12 vs. 6 ± 10 m; P < 0.01). TENS was associated with lesser postoperative pain and opiate requirements but greater circulating β-endorphin levels (P < 0.05). In conclusion, stellate ganglion TENS after coronary artery bypass graft surgery positively impacted on limb blood flow during a sympathetic stimulation maneuver, a beneficial effect associated with improved clinical and functional outcomes.

  3. Blood levels of cobalt and chromium are inversely correlated to head size after metal-on-metal resurfacing arthroplasty.

    PubMed

    Parry, Michael C; Eastaugh-Waring, Steve; Bannister, Gordon C; Learmonth, Ian D; Case, Charles Patrick; Blom, Ashley W

    2013-01-01

    Resurfacing arthroplasty has fallen out of favour in recent years due to unfavourable survivorship in joint registries and alarming reports of soft tissue reactions around metal on metal prostheses. Our aim was to assess the effect of head size, implant design and component positioning on metal production by resurfacing arthroplasties. We measured whole blood cobalt and chromium and component position in matched populations implanted with two designs of resurfacing arthroplasty over a two-year period. Both implants resulted in a significant increase in blood metal levels (p<0.001) though the ASR design generated significantly higher metal levels (p = 0.041). A significant inverse correlation was seen between component size and blood cobalt levels (p = 0.032) and blood chromium levels (p<0.001). No correlation was identified between component position and blood metal levels. Small diameter metal resurfacing components result in increased metal generation compared with larger components. As increased metal generation has been correlated to wear and therefore failure, caution must be used on implantation of smaller components and indeed, in those who require smaller components, alternative bearing materials should be considered. These results contrast with recent findings which have demonstrated early failure for larger diameter stemmed metal-on-metal prostheses.

  4. Effects of intraduodenal injection of Lactobacillus johnsonii La1 on renal sympathetic nerve activity and blood pressure in urethane-anesthetized rats.

    PubMed

    Tanida, Mamoru; Yamano, Toshihiko; Maeda, Keiko; Okumura, Nobuaki; Fukushima, Yoichi; Nagai, Katsuya

    2005-12-02

    Previously, it was shown that milk fermented with lactic acid bacteria lowers blood pressure, suggesting that metabolites or components of the bacteria have hypotensive action. To examine whether one of lactobacilli, Lactobacillus johnsonii La1 (LJLa1), a probiotic strain adhesive onto intestinal epithelial cells, or its metabolite has hypotensive action, and if so the mechanism of action, we determined the effects of intraduodenal injection of LJLa1 on blood pressure (BP) and the activity of autonomic nerves in urethane-anesthetized rats. Intraduodenal injection of LJLa1 reduced renal sympathetic nerve activity (RSNA) and BP and enhanced gastric vagal nerve activity (GVNA). Pre-treatment with thioperamide, a histaminergic H3-receptor antagonist, eliminated the effects of LJLa1 on RSNA, GVNA, and BP. Furthermore, bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN), the master circadian oscillator, abolished the suppression of RSNA and BP and the elevation of GVNA caused by LJLa1. These findings suggest that LJLa1 or its metabolites might lower BP by changing autonomic neurotransmission via the central histaminergic nerves and the suprachiasmatic nucleus in rats.

  5. Skeletal muscle fiber, nerve, and blood vessel breakdown in space-flown rats

    NASA Technical Reports Server (NTRS)

    Riley, D. A.; Ilyina-Kakueva, E. I.; Ellis, S.; Bain, J. L.; Slocum, G. R.; Sedlak, F. R.

    1990-01-01

    Histochemical and ultrastructural analyses were performed postflight on hind limb skeletal muscles of rats orbited for 12.5 days aboard the unmanned Cosmos 1887 biosatellite and returned to Earth 2 days before sacrifice. The antigravity adductor longus (AL), soleus, and plantaris muscles atrophied more than the non-weight-bearing extensor digitorum longus, and slow muscle fibers were more atrophic than fast fibers. Muscle fiber segmental necrosis occurred selectively in the AL and soleus muscles; primarily, macrophages and neutrophils infiltrated and phagocytosed cellular debris. Granule-rich mast cells were diminished in flight AL muscles compared with controls, indicating the mast cell secretion contributed to interstitial tissue edema. Increased ubiquitination of disrupted myofibrils implicated ubiquitin in myofilament degradation. Mitochondrial content and succinic dehydrogenase activity were normal, except for subsarcolemmal decreases. Myofibrillar ATPase activity of flight AL muscle fibers shifted toward the fast type. Absence of capillaries and extravasation of red blood cells indicated failed microcirculation. Muscle fiber regeneration from activated satellite cells was detected. About 17% of the flight AL end plates exhibited total or partial denervation. Thus, skeletal muscle weakness associated with spaceflight can result from muscle fiber atrophy and segmental necrosis, partial motor denervation, and disruption of the microcirculation.

  6. Blood nickel and chromium levels in association with smoking and occupational exposure among head and neck cancer patients in Tunisia.

    PubMed

    Khlifi, Rim; Olmedo, Pablo; Gil, Fernando; Feki-Tounsi, Molka; Chakroun, Amine; Rebai, Ahmed; Hamza-Chaffai, Amel

    2013-11-01

    Chronic exposure to chromium (Cr) and nickel (Ni) has long been recognized as being capable to increase head and neck cancer (HNC) incidence among exposed human populations. This study represents the first biomonitoring of Cr and Ni exposure in Tunisia and focuses on a possible association with HNC risk. The aim of the present study was to evaluate the concentrations of Cr and Ni in the blood of HNC patients and controls. Metals blood levels of 169 HNC patients and 351 controls were determined using a Perkin-Elmer Analyst 800 Atomic Absorption Spectrometer. Mean blood levels of Cr and Ni in HNC cases (52.15 and 111.60 μg/L, respectively) were significantly higher than those of controls (37.04 and 30.50 μg/L, respectively). Cases' blood levels of Cr and Ni were significantly higher than those of controls after controlling for the other risk factors of HNC, including smoking, shisha consumption, occupational exposure, and nearby environment (P<0.05). Among these risk factors, smoking and occupational exposure presented the most significant association with HNC (odds ratio (OR)=6.54 and 7.66, respectively, P<0.001). Cr and Ni levels in blood sample of cases and controls that are smoker/occupationally exposed were higher than that of non-smoker/non-occupationally exposed (P<0.05). Smokers who are occupationally exposed present the most significant association with HNC (OR=25.08, P<0.0001). High levels of blood Cr (OR=2.09) and high levels of blood Ni (OR=8.87) were strongly associated with HNC after other potential confounders were controlled (P=0.004 and P<0.0001, respectively). This study suggested a potential role of Cr and Ni in the mechanism of HNC development.

  7. Preclinical Study of Cell Therapy for Osteonecrosis of the Femoral Head with Allogenic Peripheral Blood-Derived Mesenchymal Stem Cells

    PubMed Central

    Fu, Qiang; Tang, Ning-Ning; Zhang, Qian; Liu, Yi; Peng, Jia-Chen; Fang, Ning; Yu, Li-Mei; Liu, Jin-Wei

    2016-01-01

    Purpose To explore the value of transplanting peripheral blood-derived mesenchymal stem cells from allogenic rabbits (rPBMSCs) to treat osteonecrosis of the femoral head (ONFH). Materials and Methods rPBMSCs were separated/cultured from peripheral blood after granulocyte colony-stimulating factor mobilization. Afterwards, mobilized rPBMSCs from a second passage labeled with PKH26 were transplanted into rabbit ONFH models, which were established by liquid nitrogen freezing, to observe the effect of rPBMSCs on ONFH repair. Then, the mRNA expressions of BMP-2 and PPAR-γ in the femoral head were assessed by RT-PCR. Results After mobilization, the cultured rPBMSCs expressed mesenchymal markers of CD90, CD44, CD29, and CD105, but failed to express CD45, CD14, and CD34. The colony forming efficiency of mobilized rPBMSCs ranged from 2.8 to 10.8 per million peripheral mononuclear cells. After local transplantation, survival of the engrafted cells reached at least 8 weeks. Therein, BMP-2 was up-regulated, while PPAR-γ mRNA was down-regulated. Additionally, bone density and bone trabeculae tended to increase gradually. Conclusion We confirmed that local transplantation of rPBMSCs benefits ONFH treatment and that the beneficial effects are related to the up-regulation of BMP-2 expression and the down-regulation of PPAR-γ expression. PMID:27189298

  8. Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survival in a rat model of optic nerve crush injury.

    PubMed

    Chung, Sokjoong; Rho, Seungsoo; Kim, Gijin; Kim, So-Ra; Baek, Kwang-Hyun; Kang, Myungseo; Lew, Helen

    2016-05-01

    The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underlying mechanisms responsible for optic nerve injury, such as inflammation and/or ischemia, are required. In the present study, a rat model of optic nerve crush (ONC) injury was established in order to examine the effects of transplanting human chorionic plate-derived MSCs (CP‑MSCs) isolated from the placenta, as well as human UCB mononuclear cells (CB-MNCs) on compressed rat optic nerves. Expression markers for inflammation, apoptosis, and optic nerve regeneration were analyzed, as well as the axon survival rate by direct counting. Increased axon survival rates were observed following the injection of CB‑MNCs at at 1 week post-transplantation compared with the controls. The levels of growth-associated protein-43 (GAP‑43) were increased after the injection of CB‑MNCs or CP‑MSCs compared with the controls, and the expression levels of hypoxia-inducible factor-1α (HIF-1α) were also significantly increased following the injection of CB-MNCs or CP-MSCs. ERM-like protein (ERMN) and SLIT-ROBO Rho GTPase activating protein 2 (SRGAP2) were found to be expressed in the optic nerves of the CP‑MSC-injected rats with ONC injury. The findings of our study suggest that the administration of CB‑MNCs or CP‑MSCs may promote axon survival through systemic concomitant mechanisms involving GAP‑43 and HIF‑1α. Taken together, these findings provide further understanding of the mechanisms repsonsible for optic nerve injury and may aid in the development of novel cell

  9. Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survival in a rat model of optic nerve crush injury

    PubMed Central

    CHUNG, SOKJOONG; RHO, SEUNGSOO; KIM, GIJIN; KIM, SO-RA; BAEK, KWANG-HYUN; KANG, MYUNGSEO; LEW, HELEN

    2016-01-01

    The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underlying mechanisms responsible for optic nerve injury, such as inflammation and/or ischemia, are required. In the present study, a rat model of optic nerve crush (ONC) injury was established in order to examine the effects of transplanting human chorionic plate-derived MSCs (CP-MSCs) isolated from the placenta, as well as human UCB mononuclear cells (CB-MNCs) on compressed rat optic nerves. Expression markers for inflammation, apoptosis, and optic nerve regeneration were analyzed, as well as the axon survival rate by direct counting. Increased axon survival rates were observed following the injection of CB-MNCs at at 1 week post-transplantation compared with the controls. The levels of growth-associated protein-43 (GAP-43) were increased after the injection of CB-MNCs or CP-MSCs compared with the controls, and the expression levels of hypoxia-inducible factor-1α (HIF-1α) were also significantly increased following the injection of CB-MNCs or CP-MSCs. ERM-like protein (ERMN) and SLIT-ROBO Rho GTPase activating protein 2 (SRGAP2) were found to be expressed in the optic nerves of the CP-MSC-injected rats with ONC injury. The findings of our study suggest that the administration of CB-MNCs or CP-MSCs may promote axon survival through systemic concomitant mechanisms involving GAP-43 and HIF-1α. Taken together, these findings provide further understanding of the mechanisms repsonsible for optic nerve injury and may aid in the development of novel cell-based therapeutic strategies with

  10. Evaluation of management techniques to conserve water in a mechanical head wash blood removal system.

    PubMed

    Galloway, H O; Deotte, R E; Lawrence, T E

    2013-11-01

    This research objectively evaluated methods to conserve water in a mechanical beef head wash system. Digital images of pre-wash and post-wash beef heads were analyzed to quantify the percentage change in red saturation of the image, which was used as an objective measure of cleanliness. Three types of nozzles (fan, three-hole, venturi) and three water pressures (344, 516, 689kPa) were evaluated in a two-way treatment structure. An interaction (P=0.07) was observed between water pressure and nozzle type; the change in red saturation increased as pressure decreased for fan and three-hole nozzles which contrasted with venturi nozzles. The fan nozzle×516kPa pressure treatment used 25L of water per head washed and was used to evaluate the effect of three water temperatures (15, 38, 57°C). Water temperature did not impact (P=0.21) change in red saturation. Reducing water wastage and minimizing the use of heated water could have positive economic benefits to the beef processor.

  11. Evaluation of nine oximes on in vivo reactivation of blood, brain, and tissue cholinesterase activity inhibited by organophosphorus nerve agents at lethal dose.

    PubMed

    Shih, Tsung-Ming; Skovira, Jacob W; O'Donnell, John C; McDonough, John H

    2009-09-01

    The capability of several oximes (HI-6, HLö7, MMB-4, TMB-4, carboxime, ICD 585, ICD 692, ICD 3805, and 2-PAM) to reactivate in vivo AChE inhibited by the nerve agents sarin, cyclosarin, VX, or VR in blood, brain regions, and peripheral tissues in guinea pigs was examined and compared. Animals were injected subcutaneously with 1.0 LD(50) of sarin, cyclosarin, VR, or VX, and treated intramuscularly 5 min later with one of these compounds. Toxic signs and lethality were monitored, and tissue AChE activities were determined at 60 min after nerve agent. The animals exposed to sarin or cyclosarin, alone or with non-oxime treatment, some died within 60 min; however, when treated with an oxime, no animal died. For VR or VX, all animals survived for 60 min after exposure, with or without non-oxime or oxime therapy. These nerve agents caused differential degrees of inhibition: in whole blood sarin = cyclosarin > VR = VX; in brain regions sarin > cyclosarin > VX > VR; and in peripheral tissues sarin > VX > cyclosarin > VR. These oximes exhibited differential potency in reactivating nerve agent-inhibited AChE in various peripheral tissues, but not AChE activity in the brain regions. There was no difference in the AChE reactivating potency between the dichloride and dimethanesulfonate salts of HI-6. AChE inhibited by sarin was the most and cyclosarin the least susceptible to oxime reactivation. Overall, MMB-4 appeared to be, among all oximes tested, the most effective in vivo AChE reactivator against the broadest spectrum of nerve agents.

  12. A porohyperelastic finite element model of the eye: the influence of stiffness and permeability on intraocular pressure and optic nerve head biomechanics.

    PubMed

    Ayyalasomayajula, Avinash; Park, Robert I; Simon, Bruce R; Vande Geest, Jonathan P

    2016-01-01

    Progressively deteriorating visual field is a characteristic feature of primary open-angle glaucoma (POAG), and the biomechanics of optic nerve head (ONH) is believed to be important in its onset. We used porohyperelasticity to model the complex porous behavior of ocular tissues to better understand the effect variations in ocular material properties can have on ONH biomechanics. An axisymmetric model of the human eye was constructed to parametrically study how changes in the permeabilities of retina-Bruch's-choroid complex (k(RBC)), sclera k(sclera), uveoscleral pathway (k(UVSC)) and trabecular meshwork k(TM) as well as how changes in the stiffness of the lamina cribrosa (LC) and sclera affect IOP, LC strains, and translaminar interstitial pressure gradients (TLIPG). Decreasing k(RBC) from 5 × 10(- 12) to 5 × 10(- 13) m/s increased IOP and LC strains by 17%, and TLIPG by 21%. LC strains increased by 13% and 9% when the scleral and LC moduli were decreased by 48% and 50%, respectively. In addition to the trabecular meshwork and uveoscleral pathway, the retina-Bruch's-choroid complex had an important effect on IOP, LC strains, and TLIPG. Changes in k(RBC) and scleral modulus resulted in nonlinear changes in the IOP, and LC strains especially at the lowest k(TM) and k(UVSC). This study demonstrates that porohyperelastic modeling provides a novel method for computationally studying the biomechanical environment of the ONH. Porohyperelastic simulations of ocular tissues may help provide further insight into the complex biomechanical environment of posterior ocular tissues in POAG.

  13. Bone morphogenetic protein 4 inhibits TGF-beta2 stimulation of extracellular matrix proteins in optic nerve head cells: role of gremlin in ECM modulation.

    PubMed

    Zode, Gulab S; Clark, Abbot F; Wordinger, Robert J

    2009-05-01

    The characteristic cupping of the optic nerve head (ONH) in glaucoma is associated with elevated TGF-beta2 and increased synthesis and deposition of extracellular matrix (ECM) proteins. In addition to TGF-beta2, the human ONH also expresses bone morphogenetic proteins (BMPs) and BMP receptors, which are members of the TGF-beta superfamily. We examined the potential effects of BMP4 and the BMP antagonist gremlin on TGF-beta2 induction of ECM proteins in ONH cells. BMP-4 dose dependently inhibited TGF-beta2-induced fibronectin (FN) and PAI-1 expression in ONH astrocytes and lamina cribrosa (LC) cells and also reduced TGF-beta2 stimulation of collagen I, collagen VI, and elastin. Addition of gremlin blocked this BMP-4 response, increasing cellular and secreted FN as well as PAI-1 levels in both cell types. Gremlin was expressed in ONH tissues and ONH cells, and gremlin protein levels were significantly increased in the LC region of human glaucomatous ONH tissues. Interestingly, recombinant gremlin dose dependently increased ECM protein expression in cultured ONH astrocytes and LC cells. Gremlin stimulation of ECM required activation of TGF-beta receptor and R-Smad3. TGF-beta2 increased gremlin mRNA expression and protein levels in ONH cells. Inhibition of either the type I TGF-beta receptor or Smad3 phosphorylation blocked TGF-beta2-induced gremlin expression. In conclusion, BMP4 blocked the TGF-beta2 induction of ECM proteins in ONH cells. The BMP antagonist gremlin reversed this inhibition, allowing TGF-beta2 stimulation of ECM synthesis. Increased expression of gremlin in the glaucomatous ONH may further exacerbate TGF-beta2 effects on ONH ECM metabolism by inhibiting BMP-4 antagonism of TGF-beta2 signaling. Modulation of the ECM via gremlin provides a novel therapeutic target for glaucoma.

  14. Analysis of Vision Loss Caused by Radiation-Induced Optic Neuropathy After Particle Therapy for Head-and-Neck and Skull-Base Tumors Adjacent to Optic Nerves

    SciTech Connect

    Demizu, Yusuke; Murakami, Masao; Miyawaki, Daisuke; Niwa, Yasue; Akagi, Takashi; Sasaki, Ryohei; Terashima, Kazuki; Suga, Daisaku; Kamae, Isao; Hishikawa, Yoshio

    2009-12-01

    Purpose: To assess the incident rates of vision loss (VL; based on counting fingers or more severe) caused by radiation-induced optic neuropathy (RION) after particle therapy for tumors adjacent to optic nerves (ONs), and to evaluate factors that may contribute to VL. Methods and Materials: From August 2001 to August 2006, 104 patients with head-and-neck or skull-base tumors adjacent to ONs were treated with carbon ion or proton radiotherapy. Among them, 145 ONs of 75 patients were irradiated and followed for greater than 12 months. The incident rate of VL and the prognostic factors for occurrence of VL were evaluated. The late effects of carbon ion and proton beams were compared on the basis of a biologically effective dose at alpha/beta = 3 gray equivalent (GyE{sub 3}). Results: Eight patients (11%) experienced VL resulting from RION. The onset of VL ranged from 17 to 58 months. The median follow-up was 25 months. No significant difference was observed between the carbon ion and proton beam treatment groups. On univariate analysis, age (>60 years), diabetes mellitus, and maximum dose to the ON (>110 GyE{sub 3}) were significant, whereas on multivariate analysis only diabetes mellitus was found to be significant for VL. Conclusions: The time to the onset of VL was highly variable. There was no statistically significant difference between carbon ion and proton beam treatments over the follow-up period. Based on multivariate analysis, diabetes mellitus correlated with the occurrence of VL. A larger study with longer follow-up is warranted.

  15. Astrocyte Structural and Molecular Response to Elevated Intraocular Pressure Occurs Rapidly and Precedes Axonal Tubulin Rearrangement within the Optic Nerve Head in a Rat Model

    PubMed Central

    Tehrani, Shandiz; Davis, Lauren; Cepurna, William O.; Choe, Tiffany E.; Lozano, Diana C.; Monfared, Ashley; Cooper, Lauren; Cheng, Joshua; Johnson, Elaine C.; Morrison, John C.

    2016-01-01

    Glaucomatous axon injury occurs at the level of the optic nerve head (ONH) in response to uncontrolled intraocular pressure (IOP). The temporal response of ONH astrocytes (glial cells responsible for axonal support) to elevated IOP remains unknown. Here, we evaluate the response of actin-based astrocyte extensions and integrin-based signaling within the ONH to 8 hours of IOP elevation in a rat model. IOP elevation of 60 mm Hg was achieved under isoflurane anesthesia using anterior chamber cannulation connected to a saline reservoir. ONH astrocytic extension orientation was significantly and regionally rearranged immediately after IOP elevation (inferior ONH, 43.2° ± 13.3° with respect to the anterior-posterior axis versus 84.1° ± 1.3° in controls, p<0.05), and re-orientated back to baseline orientation 1 day post IOP normalization. ONH axonal microtubule filament label intensity was significantly reduced 1 and 3 days post IOP normalization, and returned to control levels on day 5. Phosphorylated focal adhesion kinase (FAK) levels steadily decreased after IOP normalization, while levels of phosphorylated paxillin (a downstream target of FAK involved in focal adhesion dynamics) were significantly elevated 5 days post IOP normalization. The levels of phosphorylated cortactin (a downstream target of Src kinase involved in actin polymerization) were significantly elevated 1 and 3 days post IOP normalization and returned to control levels by day 5. No significant axon degeneration was noted by morphologic assessment up to 5 days post IOP normalization. Actin-based astrocyte structure and signaling within the ONH are significantly altered within hours after IOP elevation and prior to axonal cytoskeletal rearrangement, producing some responses that recover rapidly and others that persist for days despite IOP normalization. PMID:27893827

  16. A porohyperelastic finite element model of the eye: the influence of stiffness and permeability on intraocular pressure and optic nerve head biomechanics

    PubMed Central

    Ayyalasomayajula, Avinash; Park, Robert I.; Simon, Bruce R.; Geest, Jonathan P. Vande

    2015-01-01

    Purpose Progressively deteriorating visual field is a characteristic feature of primary open-angle glaucoma (POAG), and the biomechanics of optic nerve head (ONH) is believed to be important in its onset. We used porohyperelasticity to model the complex porous behavior of ocular tissues to better understand the effect variations in ocular material properties can have on ONH biomechanics. Methods An axisymmetric model of the human eye was constructed to parametrically study how changes in the permeabilities of retina-Bruch's-choroid complex (kRBC), sclera (ksclera), uveoscleral pathway (kUVSC), and trabecular meshwork (kTM) as well as how changes in the stiffness of the lamina cribrosa (LC) and sclera affect IOP, LC strains, and translaminar interstitial pressure gradients (TLIPG). Results Decreasing kRBC from 5×10−12m/s to 5×10−13m/s increased IOP and LC strains by 17%, and TLIPG by 21%. LC strains increased by 13% and 9% when the scleral and LC moduli were decreased by 48% and 50%, respectively. Conclusions In addition to the trabecular meshwork and uveoscleral pathway, the retina-Bruch's-choroid complex had an important effect on IOP, LC strains, and TLIPG. Changes in kRBC and scleral modulus resulted in nonlinear changes in the IOP, and LC strains especially at the lowest kTM and kUVSC. This study demonstrates that porohyperelastic modeling provides a novel method for computationally studying the biomechanical environment of the ONH. Porohyperelastic simulations of ocular tissues may help provide further insight into the complex biomechanical environment of posterior ocular tissues in POAG. PMID:26195024

  17. Corneal Segmentation Analysis Increases Glaucoma Diagnostic Ability of Optic Nerve Head Examination, Heidelberg Retina Tomograph's Moorfield's Regression Analysis, and Glaucoma Probability Score.

    PubMed

    Saenz-Frances, F; Jañez, L; Berrozpe-Villabona, C; Borrego-Sanz, L; Morales-Fernández, L; Acebal-Montero, A; Mendez-Hernandez, C D; Martinez-de-la-Casa, J M; Santos-Bueso, E; Garcia-Sanchez, J; Garcia-Feijoo, J

    2015-01-01

    Purpose. To study whether a corneal thickness segmentation model, consisting in a central circular zone of 1 mm radius centered at the corneal apex (zone I) and five concentric rings of 1 mm width (moving outwards: zones II to VI), could boost the diagnostic accuracy of Heidelberg Retina Tomograph's (HRT's) MRA and GPS. Material and Methods. Cross-sectional study. 121 healthy volunteers and 125 patients with primary open-angle glaucoma. Six binary multivariate logistic regression models were constructed (MOD-A1, MOD-A2, MOD-B1, MOD-B2, MOD-C1, and MOD-C2). The dependent variable was the presence of glaucoma. In MOD-A1, the predictor was the result (presence of glaucoma) of the analysis of the stereophotography of the optic nerve head (ONH). In MOD-B1 and MOD-C1, the predictor was the result of the MRA and GPS, respectively. In MOD-B2 and MOD-C2, the predictors were the same along with corneal variables: central, overall, and zones I to VI thicknesses. This scheme was reproduced for model MOD-A2 (stereophotography along with corneal variables). Models were compared using the area under the receiver operator characteristic curve (AUC). Results. MOD-A1-AUC: 0.771; MOD-A2-AUC: 0.88; MOD-B1-AUC: 0.736; MOD-B2-AUC: 0.845; MOD-C1-AUC: 0.712; MOD-C2-AUC: 0.838. Conclusion. Corneal thickness variables enhance ONH assessment and HRT's MRA and GPS diagnostic capacity.

  18. Modelling of the dynamic relationship between arterial pressure, renal sympathetic nerve activity and renal blood flow in conscious rabbits.

    PubMed

    Berger, C S; Malpas, S C

    1998-12-01

    A linear autoregressive/moving-average model was developed to describe the dynamic relationship between mean arterial pressure (MAP), renal sympathetic nerve activity (SNA) and renal blood flow (RBF) in conscious rabbits. The RBF and SNA to the same kidney were measured under resting conditions in a group of eight rabbits. Spectral analysis of the data sampled at 0.4 Hz showed that the low-pass bandwidth of the signal power for RBF was approximately 0. 05 Hz. An autoregressive/moving-average model with an exogenous input (ARMAX) was then derived (using the iterative Gauss-Newton algorithm provided by the MATLAB identification Toolbox), with MAP and SNA as inputs and RBF as output, to model the low-frequency fluctuations. The model step responses of RBF to changes in SNA and arterial pressure indicated an overdamped response with a settling time that was usually less than 2 s. Calculated residuals from the model indicated that 79 5 % (mean s.d., averaged over eight independent experiments) of the variation in RBF could be accounted for by the variations in arterial pressure and SNA. Two additional single-input models for each of the inputs were similarly obtained and showed conclusively that changes in RBF, in the conscious resting rabbit, are a function of both SNA and MAP and that the SNA signal has the predominant effect. These results indicate a strong reliance on SNA for the dynamic regulation of RBF. Such information is likely to be important in understanding the diminished renal function that occurs in a variety of disease conditions in which overactivity of the sympathetic nervous system occurs.

  19. Effects of Mild Hypercapnia During Head-Down Bed Rest on Ocular Structures, Cerebral Blood Flow, aud Visual Acuity in Healthy Human Subjects

    NASA Technical Reports Server (NTRS)

    Laurie, S. S.; Taibbi, G.; Lee, S. M. C.; Martin, D. S.; Zanello, S.; Ploutz-Snyder, R.; Hu, X.; Stenger, M. B.; Vizzeri, G.

    2014-01-01

    The cephalad fluid shift induced by microgravity has been hypothesized to cause an elevation in intracranial pressure (ICP) and contribute to the development of the Visual Impairment/Intracranial Pressure (VIIP) syndrome, as experienced by some astronauts during long-duration space flight. Elevated ambient partial pressure of carbon dioxide (PCO2) on ISS may also raise ICP and contribute to VIIP development. We seek to determine if the combination of mild CO2 exposure, similar to that occurring on the International Space Station, with the cephalad fluid shift induced by head-down tilt, will induce ophthalmic and cerebral blood flow changes similar to those described in the VIIP syndrome. We hypothesize that mild hypercapnia in the head-down tilt position will increase choroidal blood volume and cerebral blood flow, raise intraocular pressure (IOP), and transiently reduce visual acuity as compared to the seated or the head-down tilt position without elevated CO2, respectively.

  20. Blood-Brain Barrier Deterioration and Hippocampal Gene Expression in Polymicrobial Sepsis: An Evaluation of Endothelial MyD88 and the Vagus Nerve.

    PubMed

    Honig, Gerard; Mader, Simone; Chen, Huiyi; Porat, Amit; Ochani, Mahendar; Wang, Ping; Volpe, Bruce T; Diamond, Betty

    2016-01-01

    Systemic infection can initiate or exacerbate central nervous system (CNS) pathology, even in the absence of overt invasion of bacteria into the CNS. Recent epidemiological studies have demonstrated that human survivors of sepsis have an increased risk of long-term neurocognitive decline. There is thus a need for improved understanding of the physiological mechanisms whereby acute sepsis affects the CNS. In particular, MyD88-dependent activation of brain microvascular endothelial cells and a resulting loss of blood-brain barrier integrity have been proposed to play an important role in the effects of systemic inflammation on the CNS. Signaling through the vagus nerve has also been considered to be an important component of CNS responses to systemic infection. Here, we demonstrate that blood-brain barrier permeabilization and hippocampal transcriptional responses during polymicrobial sepsis occur even in the absence of MyD88-dependent signaling in cerebrovascular endothelial cells. We further demonstrate that these transcriptional responses can occur without vagus nerve input. These results suggest that redundant signals mediate CNS responses in sepsis. Either endothelial or vagus nerve activation may be individually sufficient to transmit systemic inflammation to the central nervous system. Transcriptional activation in the forebrain in sepsis may be mediated by MyD88-independent endothelial mechanisms or by non-vagal neuronal pathways.

  1. The impact of high-frequency magnetic stimulation of peripheral nerves: muscle hardness, venous blood flow, and motor function of upper extremity in healthy subjects.

    PubMed

    Okudera, Yoshihiko; Matsunaga, Toshiki; Sato, Mineyoshi; Chida, Satoaki; Hatakeyama, Kazutoshi; Watanabe, Motoyuki; Shimada, Yoichi

    2015-01-01

    The purpose of this study was to investigate the impact of high-frequency peripheral nerve magnetic stimulation on the upper limb function. Twenty-five healthy adults (16 men and 9 women) participated in this study. The radial nerve of the non-dominant hand was stimulated by high-frequency magnetic stimulation device. A total of 600 impulses were applied at a frequency of 20 Hz and intensity of 1.2 resting motor threshold (rMT). At three time points (before, immediately after, and 15 min after stimulation), muscle hardness of the extensor digitorum muscle on the stimulated side was measured using a mechanical tissue hardness meter and a shear wave imaging device, cephalic venous blood flow on the stimulated side was measured using an ultrasound system, and the Box and Block test (BBT) was performed. Mechanical tissue hardness results did not show any significant differences between before, immediately after, and 15 min after stimulation. Measurements via shear wave imaging showed that muscle hardness significantly decreased both immediately and 15 min after stimulation compared to before stimulation (P < 0.05). Peripheral venous blood flow and BBT score significantly increased both immediately and 15 min after stimulation compared to before stimulation (P < 0.01). High-frequency peripheral nerve magnetic stimulation can achieve effects similar to electrical stimulation in a less invasive manner, and may therefore become an important element in next-generation rehabilitation.

  2. Noncontact diffuse optical assessment of blood flow changes in head and neck free tissue transfer flaps (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Huang, Chong; Radabaugh, Jeffrey P.; Aouad, Rony K.; Lin, Yu; Gal, Thomas J.; Patel, Amit B.; Valentino, Joseph; Shang, Yu; Yu, Guoqiang

    2016-02-01

    Head and neck cancer accounts for 3 to 5% of all cancers in the United States. Primary or salvage surgeries are extensive and often lead to major head and neck defects that require complex reconstructions with local, regional, or free tissue transfer flaps. Knowledge of tissue blood flow (BF) changes after free tissue transfer may enable surgeons to predict the failure of flap thrombosis at an early stage. This study used our recently developed noncontact diffuse correlation spectroscopy to monitor dynamic BF changes in free flaps without getting in contact with the targeted tissue. Eight free flaps were elevated in patients with head and neck cancer; one of the flaps failed. Multiple BF measurements probing the transferred tissue were performed during and post the surgical operation. Postoperative BF values were normalized to the intraoperative baselines (assigning '1') for the calculation of relative BF change (rBF). The rBF changes over the seven successful flaps were 1.89 +/- 0.15, 2.26 +/- 0.13, and 2.43 +/- 0.13 (mean +/- standard error) respectively on postoperative days 2, 4, and 7. These postoperative values were significantly higher than the intraoperative baseline values (p < 0.001), indicating a gradual recovery of flap vascularity after the tissue transfer. By contrast, rBF changes observed from the unsuccessful flap were 1.14 and 1.34 respectively on postoperative days 2 and 4, indicating a less flow recovery. Measurement of BF recovery after flap anastomosis holds the potential to act early to salvage ischemic flaps.

  3. Genetic comparison of the head of Henri IV and the presumptive blood from Louis XVI (both Kings of France).

    PubMed

    Charlier, Philippe; Olalde, Iñigo; Solé, Neus; Ramírez, Oscar; Babelon, Jean-Pierre; Galland, Bruno; Calafell, Francesc; Lalueza-Fox, Carles

    2013-03-10

    A mummified head was identified in 2010 as belonging to Henri IV, King of France. A putative blood sample from the King Louis XVI preserved into a pyrographically decorated gourd was analyzed in 2011. Both kings are in a direct male-line descent, separated by seven generations. We have retrieved the hypervariable region 1 of the mitochondrial DNA as well as a partial Y-chromosome profile from Henri IV. Five STR loci match the alleles found in Louis XVI, while another locus shows an allele that is just one mutation step apart. Taking into consideration that the partial Y-chromosome profile is extremely rare in modern human databases, we concluded that both males could be paternally related. The likelihood ratio of the two samples belonging to males separated by seven generations (as opposed to unrelated males) was estimated as 246.3, with a 95% confidence interval between 44.2 and 9729. Historically speaking, this forensic DNA data would confirm the identity of the previous Louis XVI sample, and give another positive argument for the authenticity of the head of Henri IV.

  4. Anemia During Sequential Induction Chemotherapy and Chemoradiation for Head and Neck Cancer: The Impact of Blood Transfusion on Treatment Outcome

    SciTech Connect

    Bhide, Shreerang A.; Ahmed, Merina; Rengarajan, Vijayan; Powell, Ceri; Miah, Aisha; Newbold, Kate; Nutting, Christopher M.; Harrington, Kevin J.

    2009-02-01

    Purpose: Sequential treatment (chemotherapy followed by concomitant chemoradiation; CCRT) is increasingly being used for radical treatment of squamous cell cancer of the head and neck (SCCHN), which results in increased myelosuppression. In this study, we review the incidence of anemia and the effect of a policy of hemoglobin (Hb) maintenance by blood transfusion on disease outcomes in these patients. Methods and Materials: Retrospective review of the records of patients with SCCHN treated with sequential CCRT formed the basis of this study. The incidence of anemia and statistics on blood transfusion were documented. For the purpose of outcome analyses, patients were divided into four categories by (1) transfusion status, (2) nadir Hb concentration, (3) number of transfusion episodes, and (4) number of units of blood transfused (NOUT). Data on 3-year locoregional control (LRC), relapse-free survival (RFS), disease-specific survival (DSS), and overall survival (OS) were analyzed. Results: One hundred and sixty-nine patients were identified. The median follow-up was 23.6 months. The RFS (52% vs. 41%, p = 0.03), DSS (71% vs. 66%, p = 0.02), and OS (58% vs. 42% p = 0.005) were significantly better for patients who did not have a transfusion vs. those who did. The LRC, RFS, DSS, and OS were also significantly better for patients with nadir Hb level >12 vs. <12 g/dL and NOUT 1-4 vs. >4. Conclusion: Our study seems to suggest that blood transfusion during radical treatment for SCCHN might be detrimental. Further research should be undertaken into the complex interactions among tumor hypoxia, anemia, and the treatment of anemia before making treatment recommendations.

  5. The Activation Pattern of Blood Leukocytes in Head and Neck Squamous Cell Carcinoma Is Correlated to Survival

    PubMed Central

    Millrud, Camilla Rydberg; Månsson Kvarnhammar, Anne; Uddman, Rolf; Björnsson, Sven; Riesbeck, Kristian; Cardell, Lars Olaf

    2012-01-01

    Head and neck squamous cell carcinoma (HNSCC) is known to cause substantial immunosuppression. The present study was designed to characterize blood leukocyte activation in HNSCC and to investigate if the individual activation pattern could be related to tumor progress and survival. The leukocyte activation profile of HNSCC patients and healthy controls was assessed with flow cytometry. HNSCC patients displayed increased numbers of monocytes, neutrophils and total leukocytes as well as an enhanced neutrophil/lymphocyte ratio. In addition, patients had a higher percentage of CD69+, CD71+ and CD98+ T cell subsets and NK cells, and a reduced expression of L-selectin in CD14highCD16+ monocytes and neutrophils, when compared to controls. These changes could be correlated to both tumor burden and spread to lymph nodes. Among the cancer patients an increased neutrophil/lymphocyte ratio, a low neutrophil and CD14high CD16+ monocyte activation state and an elevated CD4/CD8 ratio were related to poor survival. In contrast, a high percentage of CD98+ Th cells appeared to be associated with a better outcome. Taken together, the present data indicate that HNSCC causes activation of blood leukocytes and that the individual activation pattern can be linked to prognosis. PMID:23251433

  6. Bupivacaine Mandibular Nerve Block Affects Intraoperative Blood Pressure and Heart Rate in a Yucatan Miniature Swine Mandibular Condylectomy Model: A Pilot Study

    PubMed Central

    Bova, Jonathan F.; da Cunha, Anderson F.; Stout, Rhett W.; Bhumiratana, Sarindr; Alfi, David M.; Eisig, Sidney B.; Vunjak-Novakovic, Gordana; Lopez, Mandi J.

    2015-01-01

    Purpose/Aim The primary objective was to evaluate the effect of a bupivacaine mandibular nerve block on intraoperative blood pressure (BP) and heart rate (HR) in response to surgical stimulation and the need for systemic analgesics postoperatively. We hypothesized that a mandibular nerve block would decrease the need for systemic analgesics both intraoperatively and postoperatively. Materials and Methods Fourteen adult male Yucatan pigs were purchased. Pigs were chemically restrained with ketamine, midazolam, and dexmedetomidine and anesthesia was maintained with isoflurane inhalant anesthesia. Pigs were randomized to receive a mandibular block with either bupivacaine (bupivacaine group) or saline (control group). A nerve stimulator was used for administration of the block with observation of masseter muscle twitch to indicate the injection site. Invasive BP and HR were measured with the aid of an arterial catheter in eight pigs. A rescue analgesic protocol consisting of fentanyl and lidocaine was administered if HR or BP values increased 20% from baseline. Postoperative pain was quantified with a customized ethogram. HR and BP were evaluated at base line, pre-rescue, 10 and 20 min post-rescue. Results Pre-rescue mean BP was significantly increased (p = .001) for the bupivacaine group. Mean intraoperative HR was significantly lower (p = .044) in the bupivacaine versus saline group. All other parameters were not significant. Conclusion Addition of a mandibular nerve block to the anesthetic regimen in the miniature pig condylectomy model may improve variations in intraoperative BP and HR. This study establishes the foundation for future studies with larger animal numbers to confirm these preliminary findings. PMID:25394295

  7. Roles for the sympathetic nervous system, renal nerves, and CNS melanocortin-4 receptor in the elevated blood pressure in hyperandrogenemic female rats

    PubMed Central

    Maranon, Rodrigo; Lima, Roberta; Spradley, Frank T.; do Carmo, Jussara M.; Zhang, Howei; Smith, Andrew D.; Bui, Elizabeth; Thomas, R. Lucas; Moulana, Mohadetheh; Hall, John E.; Granger, Joey P.

    2015-01-01

    Women with polycystic ovary syndrome (PCOS) have hyperandrogenemia and increased prevalence of risk factors for cardiovascular disease, including elevated blood pressure. We recently characterized a hyperandrogenemic female rat (HAF) model of PCOS [chronic dihydrotestosterone (DHT) beginning at 4 wk of age] that exhibits similar characteristics as women with PCOS. In the present studies we tested the hypotheses that the elevated blood pressure in HAF rats is mediated in part by sympathetic activation, renal nerves, and melanocortin-4 receptor (MC4R) activation. Adrenergic blockade with terazosin and propranolol or renal denervation reduced mean arterial pressure (MAP by telemetry) in HAF rats but not controls. Hypothalamic MC4R expression was higher in HAF rats than controls, and central nervous system MC4R antagonism with SHU-9119 (1 nmol/h icv) reduced MAP in HAF rats. Taking a genetic approach, MC4R null and wild-type (WT) female rats were treated with DHT or placebo from 5 to 16 wk of age. MC4R null rats were obese and had higher MAP than WT control rats, and while DHT increased MAP in WT controls, DHT failed to further increase MAP in MC4R null rats. These data suggest that increases in MAP with chronic hyperandrogenemia in female rats are due, in part, to activation of the sympathetic nervous system, renal nerves, and MC4R and may provide novel insights into the mechanisms responsible for hypertension in women with hyperandrogenemia such as PCOS. PMID:25695289

  8. Retrograde arterial leg blood flow during tilt-back from a head-up posture: importance of capacitive flows when arterial pressure changes.

    PubMed

    Sheriff, Don D; Nådland, Inger Helene; Toska, Karin

    2010-03-01

    The windkessel function of the arterial system converts the intermittent action of the heart into more continuous microcirculatory blood flow during diastole via the return of elastic energy stored in the walls of the arteries during systole. Might the same phenomenon occur regionally within the arterial system during tilting owing to regional differences in local arterial pressure imposed by gravity? We sought to test the hypothesis that during tilt-back from a head-up posture, the return of stored elastic energy in leg arteries would work to slow, or perhaps transiently reverse, the flow of blood in the femoral artery. Femoral artery blood flow and arterial pressure were recorded during tilt back from a 30 degrees head-up posture to supine (approximately 0.5 G) in young, healthy subjects (n = 7 males and 3 females) before and during clonidine infusion. During control (no drug) conditions femoral artery blood flow ceased for an entire heart beat during tilt-back. During clonidine infusion femoral artery blood flow reversed for at least one entire heart beat during tilt-back, i.e., blood flow in the retrograde direction in the femoral artery from the leg into the abdomen. Thus substantial capacitive effects of tilting on leg blood flow occur in humans during mild changes in posture.

  9. A comparison of blood loss during the Halal slaughter of lambs following Traditional Religious Slaughter without stunning, Electric Head-Only Stunning and Post-Cut Electric Head-Only Stunning.

    PubMed

    Khalid, Rizvan; Knowles, Toby G; Wotton, Steve B

    2015-12-01

    Blood lost at exsanguination during the Halal slaughter of lambs was compared between the slaughter methods of Traditional Religious Slaughter without stunning (TRS), Electric Head-Only Stunning (EHOS) and Post-Cut Electric Head-Only Stunning (PCEHOS). Two protocols were examined, Experimental (80 lambs) and Commercial (360 lambs), assessing varying periods of animal orientation during the 4 min bleeding process (upright orientation before vertical hanging). Live-weight, blood weight (Experimental only), carcass weights and by-product weights were recorded. The Experimental protocol highlighted an increase in blood loss at 60s in EHOS and PCEHOS compared to TRS (P<0.001) but by 90 s there was no significant difference. A post-slaughter change in animal orientation from an upright to a vertical hanging position aided the amount of blood loss. The bleeding of lambs is largely completed by 2 min. There were no significant differences (P>0.05) in final blood loss between treatments. This research was undertaken to inform discussion on the merits of different slaughter methods compatible with Halal requirements.

  10. Validation of the i-STAT and HemoCue systems for the analysis of blood parameters in the bar-headed goose, Anser indicus

    PubMed Central

    Harter, T. S.; Reichert, M.; Brauner, C. J.; Milsom, W. K.

    2015-01-01

    Every year, bar-headed geese (Anser indicus) perform some of the most remarkable trans-Himalayan migrations, and researchers are increasingly interested in understanding the physiology underlying their high-altitude flight performance. A major challenge is generating reliable measurements of blood parameters on wild birds in the field, where established analytical techniques are often not available. Therefore, we validated two commonly used portable clinical analysers (PCAs), the i-STAT and the HemoCue systems, for the analysis of blood parameters in bar-headed geese. The pH, partial pressures of O2 and CO2 (PO2 and PCO2), haemoglobin O2 saturation (sO2), haematocrit (Hct) and haemoglobin concentration [Hb] were simultaneously measured with the two PCA systems (i-STAT for all parameters; HemoCue for [Hb]) and with conventional laboratory techniques over a physiological range of PO2, PCO2 and Hct. Our results indicate that the i-STAT system can generate reliable values on bar-headed goose whole blood pH, PO2, PCO2 and Hct, but we recommend correcting the obtained values using the linear equations determined here for higher accuracy. The i-STAT is probably not able to produce meaningful measurements of sO2 and [Hb] over a range of physiologically relevant environmental conditions. However, we can recommend the use of the HemoCue to measure [Hb] in the bar-headed goose, if results are corrected. We emphasize that the equations that we provide to correct PCA results are applicable only to bar-headed goose whole blood under the conditions that we tested. We encourage researchers to validate i-STAT or HemoCue results thoroughly for their specific study conditions and species in order to yield accurate results. PMID:27293706

  11. Spatio-temporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shangbin; Chen, Haiying; Zeng, Shaoqun

    2003-10-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%)2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50%+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  12. Effect of head-down-tilt bed rest and hypovolemia on dynamic regulation of heart rate and blood pressure

    NASA Technical Reports Server (NTRS)

    Iwasaki, K. I.; Zhang, R.; Zuckerman, J. H.; Pawelczyk, J. A.; Levine, B. D.; Blomqvist, C. G. (Principal Investigator)

    2000-01-01

    Adaptation to head-down-tilt bed rest leads to an apparent abnormality of baroreflex regulation of cardiac period. We hypothesized that this "deconditioning response" could primarily be a result of hypovolemia, rather than a unique adaptation of the autonomic nervous system to bed rest. To test this hypothesis, nine healthy subjects underwent 2 wk of -6 degrees head-down bed rest. One year later, five of these same subjects underwent acute hypovolemia with furosemide to produce the same reductions in plasma volume observed after bed rest. We took advantage of power spectral and transfer function analysis to examine the dynamic relationship between blood pressure (BP) and R-R interval. We found that 1) there were no significant differences between these two interventions with respect to changes in numerous cardiovascular indices, including cardiac filling pressures, arterial pressure, cardiac output, or stroke volume; 2) normalized high-frequency (0.15-0.25 Hz) power of R-R interval variability decreased significantly after both conditions, consistent with similar degrees of vagal withdrawal; 3) transfer function gain (BP to R-R interval), used as an index of arterial-cardiac baroreflex sensitivity, decreased significantly to a similar extent after both conditions in the high-frequency range; the gain also decreased similarly when expressed as BP to heart rate x stroke volume, which provides an index of the ability of the baroreflex to alter BP by modifying systemic flow; and 4) however, the low-frequency (0.05-0.15 Hz) power of systolic BP variability decreased after bed rest (-22%) compared with an increase (+155%) after acute hypovolemia, suggesting a differential response for the regulation of vascular resistance (interaction, P < 0.05). The similarity of changes in the reflex control of the circulation under both conditions is consistent with the hypothesis that reductions in plasma volume may be largely responsible for the observed changes in cardiac

  13. Bone, blood vessels, and muscle detection algorithm and creating database based on dynamic and non-dynamic multi-slice CT image of head and neck

    NASA Astrophysics Data System (ADS)

    Shabbir Ahamed, Mohammed; Kubo, Mitsuru; Kawata, Yoshiki; Niki, Noboru; Iwasaki, Hirokazu

    2007-03-01

    Nowadays, dental CT images play more and more important roles in oral clinical applications. Our research is important particularly in the field of dentistry. We are using non-dynamic and dynamic CT image for our research. We are creating our database of bone, blood vessels and muscles of head and neck. This database contains easy case and difficult case of head and neck's bone, blood vessels and muscle. There are lots of difficult cases in our database. Teeth separation and condylar process separation is difficult case. External carotid artery has many branches and they are attached with vain so it is difficult to separate. All muscle threshold value is same and they are attaching with each other so muscle separation is very difficult. These databases also contain different age's patients. For this reason our database becomes an important tool for dental students and also important assets for diagnosis. After completion our database we can link it with other dental application.

  14. Murder or not? Cold temperature makes criminals appear to be cold-blooded and warm temperature to be hot-headed.

    PubMed

    Gockel, Christine; Kolb, Peter M; Werth, Lioba

    2014-01-01

    Temperature-related words such as cold-blooded and hot-headed can be used to describe criminal behavior. Words associated with coldness describe premeditated behavior and words associated with heat describe impulsive behavior. Building on recent research about the close interplay between physical and interpersonal coldness and warmth, we examined in a lab experiment how ambient temperature within a comfort zone influences judgments of criminals. Participants in rooms with low temperature regarded criminals to be more cold-blooded than participants in rooms with high temperature. Specifically, they were more likely to attribute premeditated crimes, ascribed crimes resulting in higher degrees of penalty, and attributed more murders to criminals. Likewise, participants in rooms with high temperature regarded criminals to be more hot-headed than participants in rooms with low temperature: They were more likely to attribute impulsive crimes. Results imply that cognitive representations of temperature are closely related to representations of criminal behavior and attributions of intent.

  15. Murder or Not? Cold Temperature Makes Criminals Appear to Be Cold-Blooded and Warm Temperature to Be Hot-Headed

    PubMed Central

    Gockel, Christine; Kolb, Peter M.; Werth, Lioba

    2014-01-01

    Temperature-related words such as cold-blooded and hot-headed can be used to describe criminal behavior. Words associated with coldness describe premeditated behavior and words associated with heat describe impulsive behavior. Building on recent research about the close interplay between physical and interpersonal coldness and warmth, we examined in a lab experiment how ambient temperature within a comfort zone influences judgments of criminals. Participants in rooms with low temperature regarded criminals to be more cold-blooded than participants in rooms with high temperature. Specifically, they were more likely to attribute premeditated crimes, ascribed crimes resulting in higher degrees of penalty, and attributed more murders to criminals. Likewise, participants in rooms with high temperature regarded criminals to be more hot-headed than participants in rooms with low temperature: They were more likely to attribute impulsive crimes. Results imply that cognitive representations of temperature are closely related to representations of criminal behavior and attributions of intent. PMID:24788725

  16. Effects of nerve growth factor (NGF) on blood vessels area and expression of the angiogenic factors VEGF and TGFbeta1 in the rat ovary

    PubMed Central

    Julio-Pieper, Marcela; Lara, Hernán E; Bravo, Javier A; Romero, Carmen

    2006-01-01

    Background Angiogenesis is a crucial process in follicular development and luteogenesis. The nerve growth factor (NGF) promotes angiogenesis in various tissues. An impaired production of this neurotrophin has been associated with delayed wound healing. A variety of ovarian functions are regulated by NGF, but its effects on ovarian angiogenesis remain unknown. The aim of this study was to elucidate if NGF modulates 1) the amount of follicular blood vessels and 2) ovarian expression of two angiogenic factors: vascular endothelial growth factor (VEGF) and transforming growth factor beta 1 (TGFbeta1), in the rat ovary. Results In cultured neonatal rat ovaries, NGF increased VEGF mRNA and protein levels, whereas TGFbeta1 expression did not change. Sectioning of the superior ovarian nerve, which increases ovarian NGF protein content, augmented VEGF immunoreactivity and the area of capillary vessels in ovaries of prepubertal rats compared to control ovaries. Conclusion Results indicate that NGF may be important in the maintenance of the follicular and luteal vasculature in adult rodents, either indirectly, by increasing the expression of VEGF in the ovary, or directly via promoting the proliferation of vascular cells. This data suggests that a disruption on NGF regulation could be a component in ovarian disorders related with impaired angiogenesis. PMID:17096853

  17. Synchronized reconstitution of muscle fibers, peripheral nerves and blood vessels by murine skeletal muscle-derived CD34(-)/45 (-) cells.

    PubMed

    Tamaki, Tetsuro; Okada, Yoshinori; Uchiyama, Yoshiyasu; Tono, Kayoko; Masuda, Maki; Wada, Mika; Hoshi, Akio; Akatsuka, Akira

    2007-10-01

    In order to establish the practical isolation and usage of skeletal muscle-derived stem cells (MDSCs), we determined reconstitution capacity of CD34(-)/CD45(-) (Sk-DN) cells as a candidate somatic stem cell source for transplantation. Sk-DN cells were enzymatically isolated from GFP transgenic mice (C57/BL6N) skeletal muscle and sorted using fluorescence activated cell sorting (FACS), and expanded by collagen gel-based cell culture with bFGF and EGF. The number of Sk-DN cells was small after sorting (2-8 x 10(4)); however, the number increased 10-20 fold (2-16 x 10(5)) after 6 days of expansion culture, and the cells maintained immature state and multipotency, expressing mRNAs for mesodermal and ectodermal cell lineages. Transplantation of expanded Sk-DN cells into the severe muscle damage model (C57/BL6N wild-type) resulted in the synchronized reconstitution of blood vessels, peripheral nerves and muscle fibers following significant recovery of total muscle mass (57%) and contractile function (55%), whereas the non-cell-transplanted control group showed around 20% recovery in both factors. These reconstitution capacities were supported by the intrinsic plasticity of Sk-DN cells that can differentiate into muscular (skeletal muscle), vascular (pericyte, endothelial cell and smooth muscle) and peripheral nerve (Schwann cells and perineurium) cell lineages that was revealed by transplantation to non-muscle tissue (beneath renal capsule) and fluorescence in situ hybridization (FISH) analysis.

  18. Blood

    MedlinePlus

    ... The liquid part, called plasma, is made of water, salts, and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells, and platelets. Red ...

  19. Electromyographic (EMG) neuromonitoring in otolaryngology-head and neck surgery.

    PubMed

    Dillon, Francis X

    2010-09-01

    Intraoperative neuromonitoring (IONM) is a relatively recent advance in electromyography (EMG) applied to otolaryngology-head and neck surgery. Its purpose is to allow real-time identification and functional assessment of vulnerable nerves during surgery. The nerves most often monitored in head and neck surgery are the motor branch of the facial nerve (VII), the recurrent or inferior laryngeal nerves (X), the vagus nerve (X), and the spinal accessory nerve (XI), with other cranial lower nerves monitored less frequently. Morbidity from trauma to these nerves is significant and obvious, such as unilateral facial paresis. Although functional restorative surgery is usually considered to repair the effects of such an insult, the importance of preventing nerve injury in head and neck surgery is obvious. This article focuses on the anesthetic considerations pertinent to IONM of peripheral cranial nerves during otolaryngologic-head and neck surgery. The specific modality of IONM is EMG, both spontaneous and evoked.

  20. Role of the vegus nerve in epilepsy (image)

    MedlinePlus

    The vagus nerves branch off the brain on either side of the head and travel down the neck, along the ... the body, and affect swallowing and speech. The vagus nerves also connect to parts of the brain involved ...

  1. Treating Head Lice

    MedlinePlus

    ... 180 K) En Español On this page: Blood-Sucking Bugs Steps for Safe Use Heading Off Head Lice Head lice. Every parent’s nightmare. A year-round problem, the number of cases seems to peak when ...

  2. Role of capsaicin sensitive nerves in epidermal growth factor effects on gastric mucosal injury and blood flow

    PubMed Central

    Kang, J; Teng, C; Chen, F; Wee, A

    1998-01-01

    Background—Epidermal growth factor (EGF) and capsaicin protect against experimental gastric mucosal injury. Capsaicin exerts its gastroprotective effect by stimulating afferent neurones leading to release of calcitonin gene related peptide (CGRP) which causes gastric hyperaemia. EGF also causes gastric hyperaemia but whether it acts via capsaicin sensitive neurones is unknown. 
Aims—To assess the influence of: (1) capsaicin desensitisation on EGF effects on gastric mucosal injury and gastric mucosal blood flow; and (2) close arterial infusion of hCGRP8-37, a CGRP antagonist, on EGF effects on gastric mucosal blood flow. 
Methods—The absolute ethanol induced gastric mucosal injury model in the rat was used. Gastric mucosal damage was assessed by planimetry and light microscopy. Gastric mucosal blood flow was measured by laser Doppler flowmetry in a gastric chamber preparation. 
Results—Capsaicin desensitisation abolished the gastroprotective and gastric hyperaemic effects of EGF. Close arterial infusion of hCGRP8-37 antagonised the hyperaemic effect of both capsaicin and EGF. 
Conclusion—Results show that EGF may exert its gastroprotective and gastric hyperaemic effects via capsaicin sensitive afferent neurones. 

 Keywords: capsaicin; epidermal growth factor; gastric mucosal injury; gastric mucosal blood flow; calcitonin gene related peptide antagonist; rat PMID:9577339

  3. Determining degree of optic nerve edema from color fundus photography

    NASA Astrophysics Data System (ADS)

    Agne, Jason; Wang, Jui-Kai; Kardon, Randy H.; Garvin, Mona K.

    2015-03-01

    Swelling of the optic nerve head (ONH) is subjectively assessed by clinicians using the Frisén scale. It is believed that a direct measurement of the ONH volume would serve as a better representation of the swelling. However, a direct measurement requires optic nerve imaging with spectral domain optical coherence tomography (SD-OCT) and 3D segmentation of the resulting images, which is not always available during clinical evaluation. Furthermore, telemedical imaging of the eye at remote locations is more feasible with non-mydriatic fundus cameras which are less costly than OCT imagers. Therefore, there is a critical need to develop a more quantitative analysis of optic nerve swelling on a continuous scale, similar to SD-OCT. Here, we select features from more commonly available 2D fundus images and use them to predict ONH volume. Twenty-six features were extracted from each of 48 color fundus images. The features include attributes of the blood vessels, optic nerve head, and peripapillary retina areas. These features were used in a regression analysis to predict ONH volume, as computed by a segmentation of the SD-OCT image. The results of the regression analysis yielded a mean square error of 2.43 mm3 and a correlation coefficient between computed and predicted volumes of R = 0:771, which suggests that ONH volume may be predicted from fundus features alone.

  4. Blood

    MedlinePlus

    ... that die or are lost from the body. White Blood Cells White blood cells (WBCs, and also ... of severe pain. previous continue Diseases of the White Blood Cells Neutropenia (pronounced: new-truh-PEE-nee- ...

  5. Nerve transfers in brachial plexus birth palsies: indications, techniques, and outcomes.

    PubMed

    Kozin, Scott H

    2008-11-01

    The advent of nerve transfers has greatly increased surgical options for children who have brachial plexus birth palsies. Nerve transfers have considerable advantages, including easier surgical techniques, avoidance of neuroma resection, and direct motor and sensory reinnervation. Therefore, any functioning nerve fibers within the neuroma are preserved. Furthermore, a carefully selected donor nerve results in little or no clinical deficit. However, some disadvantages and unanswered questions remain. Because of a lack of head-to-head comparison between nerve transfers and nerve grafting, the window of opportunity for nerve grafting may be missed, which may degrade the ultimate outcome. Time will tell the ultimate role of nerve transfer or nerve grafting.

  6. Nerve biopsy

    MedlinePlus

    ... Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis Risks Allergic reaction to the local anesthetic Discomfort ... Neurosarcoidosis Peripheral neuropathy Primary amyloidosis Radial nerve dysfunction Sarcoidosis Tibial nerve dysfunction Review Date 6/1/2015 ...

  7. The anti-apoptotic and neuro-protective effects of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) on acute optic nerve injury is transient.

    PubMed

    Chen, Meilan; Xiang, Zhenghua; Cai, Jiping

    2013-09-26

    Progressive death of retinal ganglion cells (RGCs) is a major cause of irreversible visual impairment after optic nerve injury. Clinically, there are still no effective treatments for recovering the visual function at present. The probable approaches to maintain the vision and RGCs function involve in preventing RGCs from death and/or promoting the regeneration of damaged RGCs. Previous studies have shown that mesenchymal stem cells (MSCs) take neuroprotective effects on ischemia-induced cortical and spinal cord injury, however, whether MSCs have a beneficial effect on the optical nerve injury is not clearly determined. In present study, we transplanted MSCs derived from human umbilical cord blood (hUCB-MSCs) into the vitreous cavity of adult rats and investigated the probable capacity of anti-apoptosis and pro-neuroprotective effects on RGCs. RGCs were retrogradely traced by fluorescent gold particles (FG); cellular apoptosis was investigated by caspase-3 immunohistochemistry and terminal dUTP nick end labeling (TUNEL) staining. Hematoxylin-eosin (HE) staining was used to observe the morphological changes of the retina. Growth associated protein 43 (GAP-43), an established marker for axonal regeneration, was used to visualize the regenerative process over time. Expression of P2X7 receptors (P2X7R), which are responsible for inflammatory and immune responses, was also monitored in our experiments. We found that the hUCB-MSC transplantation significantly decreased cellular apoptosis and promoted the survival of RGCs in early phase. However, this protection was transient and the RGCs could not be protected from death in the end. Consistent with apoptosis detection, P2X7R was also significantly decreased in hUCB-MSC transplanted rats in the early time but without obvious difference to the rats from control group in the end. Thus, our results imply that hUCB-MSCs take anti-apoptotic, pro-neuroregenerative and anti-inflammatory effects in the early time for acute optic

  8. Distinctive Steady-State Heart Rate and Blood Pressure Responses to Passive Robotic Leg Exercise and Functional Electrical Stimulation during Head-Up Tilt

    PubMed Central

    Sarabadani Tafreshi, Amirehsan; Riener, Robert; Klamroth-Marganska, Verena

    2016-01-01

    Introduction: Tilt tables enable early mobilization of patients by providing verticalization. But there is a high risk of orthostatic hypotension provoked by verticalization, especially after neurological diseases such as spinal cord injury. Robot-assisted tilt tables might be an alternative as they add passive robotic leg exercise (PE) that can be enhanced with functional electrical stimulation (FES) to the verticalization, thus reducing the risk of orthostatic hypotension. We hypothesized that the influence of PE on the cardiovascular system during verticalization (i.e., head-up tilt) depends on the verticalization angle, and FES strengthens the PE influence. To test our hypotheses, we investigated the PE effects on the cardiovascular parameters heart rate (HR), and systolic and diastolic blood pressures (sBP, dBP) at different angles of verticalization in a healthy population. Methods: Ten healthy subjects on a robot-assisted tilt table underwent four different study protocols while HR, sBP, and dBP were measured: (1) head-up tilt to 60° and 71° without PE; (2) PE at 20°, 40°, and 60° of head-up tilt; (3) PE while constant FES intensity was applied to the leg muscles, at 20°, 40°, and 60° of head-up tilt; (4) PE with variation of the applied FES intensity at 0°, 20°, 40°, and 60° of head-up tilt. Linear mixed models were used to model changes in HR, sBP, and dBP responses. Results: The models show that: (1) head-up tilt alone resulted in statistically significant increases in HR and dBP, but no change in sBP. (2) PE during head-up tilt resulted in statistically significant changes in HR, sBP, and dBP, but not at each angle and not always in the same direction (i.e., increase or decrease of cardiovascular parameters). Neither adding (3) FES at constant intensity to PE nor (4) variation of FES intensity during PE had any statistically significant effects on the cardiovascular parameters. Conclusion: The effect of PE on the cardiovascular system during

  9. Acute inhibition of the hypothalamic paraventricular nucleus decreases renal sympathetic nerve activity and arterial blood pressure in water-deprived rats.

    PubMed

    Stocker, Sean D; Keith, Kimberly J; Toney, Glenn M

    2004-04-01

    The present study was performed to determine whether sympathetic outflow and arterial blood pressure in water-deprived rats are dependent on the ongoing neuronal activity of the hypothalamic paraventricular nucleus (PVN). Renal sympathetic nerve activity (RSNA), mean arterial blood pressure (MAP), and heart rate were recorded in urethane-alpha-chloralose-anesthetized rats that were deprived of water but not food for 48 h before experiments. Acute inhibition of the PVN by bilateral microinjection of the GABA(A) agonist muscimol (100 pmol/side) significantly decreased RSNA in water-deprived rats (-26.7 +/- 4.7%, n = 7) but was without effect in control rats (1.3 +/- 6.3%, n = 7). Similarly, injection of muscimol produced a greater decrease in MAP in water-deprived rats than in control rats (-46 +/- 3 vs. -16 +/- 3 mmHg, respectively), although baseline MAP was not different between groups (105 +/- 4 vs. 107 +/- 4 mmHg, respectively). Neither bilateral microinjection of isotonic saline vehicle (100 nl/side) into the PVN nor muscimol (100 pmol/side) outside the PVN altered RSNA or MAP in either group. In addition, ganglionic blockade with hexamethonium (30 mg/kg i.v.) significantly decreased MAP in both groups; however, the decrease in MAP was significantly greater in water-deprived rats than in control rats (62 +/- 2 vs. 48 +/- 2 mmHg, respectively). Collectively, these findings suggest that sympathetic outflow contributes more to the maintenance of blood pressure in the water-deprived rat, and this depends, at least partly, on the ongoing activity of PVN neurons.

  10. Running Head: Feasibility of Blood Management. Feasibility Study of a Blood Management Program in the Mike O’Callaghan Federal Hospital

    DTIC Science & Technology

    2009-06-02

    transfusions will have widespread benefits for both patient safety and the bottom line of the MOFH. Following through with the blood management committee...32 Table 8: Cost Savings Analysis, Scenario 1 33 Table 9: Cost Savings from Elimination of Patient Autologous Donation 34 Blood Management 6...blood management program in the MOFH. The primary objective of this proposal, consistent with the mission of the MOFH, is to improve patient

  11. Release of beta-nicotinamide adenine dinucleotide upon stimulation of postganglionic nerve terminals in blood vessels and urinary bladder.

    PubMed

    Smyth, Lisa M; Bobalova, Janette; Mendoza, Michael G; Lew, Christy; Mutafova-Yambolieva, Violeta N

    2004-11-19

    Chemical signaling in autonomic neuromuscular transmission involves agents that function as neurotransmitters and/or neuromodulators. Using high performance liquid chromatography techniques with fluorescence and electrochemical detection we observed that, in addition to ATP and norepinephrine (NE), electrical field stimulation (EFS, 4-16 Hz, 0.1-0.3 ms, 15 V, 60-120 s) of isolated vascular and non-vascular preparations co-releases a previously unidentified compound with apparent nucleotide or nucleoside structure. Extensive screening of more than 25 nucleotides and nucleosides followed by detailed peak identification revealed that beta-nicotinamide adenine dinucleotide (beta-NAD) is released in tissue superfusates upon EFS of canine mesenteric artery (CMA), canine urinary bladder, and murine urinary bladder in the amounts of 7.1 +/- 0.7, 26.5 +/- 4.5, and 15.1 +/- 3.2 fmol/mg of tissue, respectively. Smaller amounts of the beta-NAD metabolites cyclic adenosine 5'-diphosphoribose (cADPR) and ADPR were also present in the superfusates collected during EFS of CMA (2.5 +/- 0.9 and 5.8 +/- 0.8 fmol/mg of tissue, respectively), canine urinary bladder (1.8 +/- 0.5 and 9.0 +/- 6.0 fmol/mg of tissue, respectively), and murine urinary bladder (1.4 +/- 0.1 and 6.2 +/- 2.4 fmol/mg of tissue, respectively). The three nucleotides were also detected in the samples collected before EFS (0.2-1.6 fmol/mg of tissue). Exogenous beta-NAD, cADPR, and ADPR (all 100 nm) reduced the release of NE in CMA at 16 Hz from 27.8 +/- 6.0 fmol/mg of tissue to 15.5 +/- 5.0, 12 +/- 3.0, and 10.0 +/- 4.0 fmol/mg of tissue, respectively. In conclusion, we detected constitutive and nerve-evoked overflow of beta-NAD, cADPR, and ADPR in vascular and non-vascular smooth muscles, beta-NAD being the prevailing compound. These substances modulate the release of NE, implicating novel nucleotide mechanisms of autonomic nervous system control of smooth muscle.

  12. The effects of treatment with alpha-lipoic acid or evening primrose oil on vascular hemostatic and lipid risk factors, blood flow, and peripheral nerve conduction in the streptozotocin-diabetic rat.

    PubMed

    Ford, I; Cotter, M A; Cameron, N E; Greaves, M

    2001-08-01

    Oxidative stress and defective fatty acid metabolism in diabetes may lead to impaired nerve perfusion and contribute to the development of peripheral neuropathy. We studied the effects of 2-week treatments with evening primrose oil (EPO; n = 16) or the antioxidant alpha-lipoic acid (ALA; n = 16) on endoneurial blood flow, nerve conduction parameters, lipids, coagulation, and endothelial factors, in rats with streptozotocin-induced diabetes. Compared with their nondiabetic littermates, untreated diabetic rats had impaired sciatic motor and saphenous sensory nerve-conduction velocity (NCV; P <.001), reduced endoneurial blood flow (P <.001), and increased serum triglycerides (P <.01), cholesterol (P < 0.01), plasma factor VII (P <.0001), and von Willebrand factor (vWF; P <.0001). Plasma fibrinogen and serum high-density lipoprotein concentrations were not significantly different. Treatment with either ALA or EPO effectively corrected the deficits in NCV and endoneurial blood flow. ALA was associated with marked and statistically significant decreases in fibrinogen, factor VII, vWF, and triglycerides (P <.01, paired t tests before v after treatment). In contrast, EPO was associated with significant (P <.05) increases in fibrinogen, factor VII, vWF, triglycerides, and cholesterol and a significant decrease in high-density lipoprotein. Changes in levels of coagulation factors and lipids, qualitatively similar to those found with EPO, were obtained with a diet containing sunflower oil (to control for calorific and lipid content) or with a normal diet alone. Blood glucose and hematocrit levels were not significantly altered by treatments. These data suggest that although both ALA and EPO improve blood flow and nerve function, their actions on vascular factors differ. The marked effects of ALA in lowering lipid and hemostatic risk factors for cardiovascular disease indicate potential antithrombotic and antiatherosclerotic actions that could be of benefit in human diabetes

  13. Common peroneal nerve dysfunction

    MedlinePlus

    Neuropathy - common peroneal nerve; Peroneal nerve injury; Peroneal nerve palsy ... type of peripheral neuropathy (damage to nerves outside the brain ... nerve injuries. Damage to the nerve disrupts the myelin sheath ...

  14. Identification of a Role for the PfEMP1 Semi-Conserved Head Structure in Protein Trafficking to the Surface of Plasmodium falciparum Infected Red Blood Cells

    PubMed Central

    Melcher, Martin; Muhle, Rebecca A.; Henrich, Philipp P.; Kraemer, Susan M.; Avril, Marion; Vigan-Womas, Ines; Mercereau-Puijalon, Odile; Smith, Joseph D.; Fidock, David A.

    2010-01-01

    Summary Transport of Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) variants to the red blood cell (RBC) surface enables malarial parasite evasion of host immunity by modifying the antigenic and adhesive properties of infected RBCs. In this study, we applied the Bxb1 integrase system to integrate transgenes encoding truncated PfEMP1-GFP fusions into cytoadherent A4 parasites and characterize their surface transport requirements. Our studies revealed that the semi-conserved head structure of PfEMP1 proteins, in combination with the predicted transmembrane region and cytoplasmic tail, encodes sufficient information for RBC surface display. In contrast, miniPfEMP1 proteins with truncated head structures were exported to the RBC cytoplasm but were not detected at the RBC surface by flow cytometry or immuno-electron microscopy. We demonstrated the absence of a mechanistic barrier to having native and miniPfEMP1 proteins displayed simultaneously at the RBC surface. However, surface exposed miniPfEMP1 proteins did not convey cytoadherence properties to their host cells, implicating potential steric considerations in host-receptor interactions or the need for multiple domains to mediate cell binding. This study establishes a new system to investigate PfEMP1 transport and demonstrates that the PfEMP1 semi-conserved head structure is under selection for protein transport, in addition to its known roles in adhesion. PMID:20438573

  15. Identification of a role for the PfEMP1 semi-conserved head structure in protein trafficking to the surface of Plasmodium falciparum infected red blood cells.

    PubMed

    Melcher, Martin; Muhle, Rebecca A; Henrich, Philipp P; Kraemer, Susan M; Avril, Marion; Vigan-Womas, Ines; Mercereau-Puijalon, Odile; Smith, Joseph D; Fidock, David A

    2010-10-01

    Transport of Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) variants to the red blood cell (RBC) surface enables malarial parasite evasion of host immunity by modifying the antigenic and adhesive properties of infected RBCs. In this study, we applied the Bxb1 integrase system to integrate transgenes encoding truncated PfEMP1-GFP fusions into cytoadherent A4 parasites and characterize their surface transport requirements. Our studies revealed that the semi-conserved head structure of PfEMP1 proteins, in combination with the predicted transmembrane region and cytoplasmic tail, encodes sufficient information for RBC surface display. In contrast, miniPfEMP1 proteins with truncated head structures were exported to the RBC cytoplasm but were not detected at the RBC surface by flow cytometry or immuno-electron microscopy. We demonstrated the absence of a mechanistic barrier to having native and miniPfEMP1 proteins displayed simultaneously at the RBC surface. However, surface-exposed miniPfEMP1 proteins did not convey cytoadherence properties to their host cells, implicating potential steric considerations in host-receptor interactions or the need for multiple domains to mediate cell binding. This study establishes a new system to investigate PfEMP1 transport and demonstrates that the PfEMP1 semi-conserved head structure is under selection for protein transport, in addition to its known roles in adhesion.

  16. The immunologic considerations in human head transplantation.

    PubMed

    Hardy, Mark A; Furr, Allen; Barret, Juan P; Barker, John H

    2017-01-24

    The idea of head transplantation appears at first as unrealistic, unethical, and futile. Here we discuss immunological considerations in human head transplantation. In a separate accompanying article we discuss surgical, ethical, and psychosocial issues concerned in body-to-head transplantation (BHT) [1]. The success of such an unusual allograft, where the donor and the recipient can reject each other, depends on prevention of complex immunologic reactions, especially rejection of the head by the body (graft-vs-host) or probably less likely, the possibility of the head rejecting the total body allograft (host-vs-graft). The technical and immunologic difficulties are enormous, especially since rapid nerve and cord connections and regeneration have not yet been possible to achieve. In this article we begin by briefly reviewing neuro-immunologic issues that may favor BHT such as the blood brain barrier (BBB) and point out its shortcomings. And we touch on the cellular and humoral elements in the brain proper that differ in some respects from those in other organs and in the periphery. Based on recent successes in vascular composite allografts (VCAs), we will elaborate on potential specific advantages and difficulties in BHT of various available immunosuppressive medications already utilized in VCAs. The risk/benefit ratio of these drugs will be emphasized in relation to direct brain toxicity such as seizure disorders, interference, or promotion of nerve regeneration, and potentiation of cerebral viral infections. The final portion of this article will focus on pre-transplant immunologic manipulation of the deceased donor body along with pretreatment of the recipient.

  17. CT angiography - head and neck

    MedlinePlus

    ... medlineplus.gov/ency/article/007677.htm CT angiography - head and neck To use the sharing features on this page, ... create pictures of the blood vessels in the head and neck. How the Test is Performed You will be ...

  18. Ultrasonography Evaluation of Vulnerable Vessels Around Cervical Nerve Roots During Selective Cervical Nerve Root Block

    PubMed Central

    2017-01-01

    Objective To evaluate the prevalence of vulnerable blood vessels around cervical nerve roots before cervical nerve root block in the clinical setting. Methods This retrospective study included 74 patients with cervical radiculopathy who received an ultrasonography-guided nerve block at an outpatient clinic from July 2012 to July 2014. Before actual injection of the steroid was performed, we evaluated the vulnerable blood vessels around each C5, C6, and C7 nerve root of each patient's painful side, with Doppler ultrasound. Results Out of 74 cases, the C5 level had 2 blood vessels (2.7%), the C6 level had 4 blood vessels (5.45%), and the C7 level had 6 blood vessels (8.11%) close to each targeted nerve root. Moreover, the C5 level had 2 blood vessels (2.7%), the C6 level 5 blood vessels (6.75%), and the C7 level had 4 blood vessels (5.45%) at the site of an imaginary needle's projected pathway to the targeted nerve root, as revealed by axial transverse ultrasound imaging with color Doppler imaging. In total, the C5 level had 4 blood vessels (5.45%), the C6 level 9 blood vessels (12.16%), and the C7 level 10 had blood vessels (13.51%) either at the targeted nerve root or at the site of the imaginary needle's projected pathway to the targeted nerve root. There was an unneglectable prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of the needle' projected pathway to the nerve root. Also, it shows a higher prevalence of vulnerable blood vessels either at the targeted nerve root or at the site of an imaginary needle's projected pathway to the nerve root as the spinal nerve root level gets lower. Conclusion To prevent unexpected critical complications involving vulnerable blood vessel injury during cervical nerve root block, it is recommended to routinely evaluate for the presence of vulnerable blood vessels around each cervical nerve root using Doppler ultrasound imaging before the cervical nerve root block, especially for the lower

  19. Head injuries.

    PubMed

    Yanko, J

    1984-08-01

    In summary, the broad term "head injury" represents a large variety of more specific injuries. In order to anticipate and plan appropriate patient care, nurses need information regarding the cause of injury, the impact site, and the patient's clinical course in addition to current assessment findings. The nurse must also anticipate sequelae from secondary brain injury due to hypoxia, edema, increased intracranial pressure, changes in regional blood flows, or hypovolemic shock due to internal bleeding in another body system or cavity. The head-injured patient is a complex patient requiring intensive nursing care, observation, and assessment. By incorporating knowledge of the mechanisms of injury into nursing observations and assessments, nurses can provide more effective nursing interventions.

  20. Pre-Operative Image-based Segmentation of the Cranial Nerves and Blood Vessels in Microvascular Decompression: Can we Prevent Unnecessary Explorations?

    PubMed Central

    Dolati, P; Golby, A; Eichberg, D; Abolfotoh, M; Dunn, IF; Mukundan, S; Hulou, MM; Al-Mefty, O

    2016-01-01

    Objectives This study was conducted to validate the accuracy of image-based pre-operative segmentation using the gold standard endoscopic and microscopic findings for localization and pre-operative diagnosis of the offensive vessel. Patients and Methods Fourteen TN and 6 HS cases were randomly selected. All patients had 3T MRI, which included thin-sectioned 3D space T2, 3D Time of Flight and MPRAGE Sequences. Imaging sequences were loaded in BrainLab iPlanNet and fused. Individual segmentation of the affected cranial nerves and the compressing vascular structure was performed by a neurosurgeon, and the results were compared with the microscopic and endoscopic findings by two blinded neurosurgeons. For each case, at least three neurovascular landmarks were targeted. Each segmented neurovascular element was validated by manual placement of the navigation probe over each target, and errors of localization were measured in mm. Results All patients underwent retro-sigmoid craniotomy and MVD using both microscope and endoscope. Based on image segmentation, the compressing vessel was identified in all cases except one, which was also negative intraoperatively. Perfect correspondence was found between image-based segmentation and endoscopic and microscopic images and videos (Dice coefficient of 1). Measurement accuracy was 0.45+/-0.21 mm (mean +/-SD). Conclusion Image-based segmentation is a promising method for pre-operative identification and localization of offending blood vessels causing HFS and TN. Using this method may prevent some unnecessary explorations on especially atypical cases with no vascular contacts. However, negative pre-operative image segmentation may not preclude one from exploration in classic cases of TN or HFS. A multicenter study with larger number of cases is recommended. PMID:26476700

  1. Highly Sensitive and Selective Immuno-capture/Electrochemical Assay of Acetylcholinesterase Activity in Red Blood Cells: A Biomarker of Exposure to Organophosphorus Pesticides and Nerve Agents

    SciTech Connect

    Chen, Aiqiong; Du, Dan; Lin, Yuehe

    2012-02-09

    Acetylcholinesterase (AChE) enzyme activity in red blood cells (RBCs) is a useful biomarker for biomonitoring of exposures to organophosphorus (OP) pesticides and chemical nerve agents. In this paper, we reported a new method for AChE activity assay based on selective immuno-capture of AChE from biological samples followed by enzyme activity assay of captured AChE using a disposable electrochemical sensor. The electrochemical sensor is based on multiwalled carbon nanotubes-gold nanocomposites (MWCNTs-Au) modified screen printed carbon electrode (SPCE). Upon the completion of immunoreaction, the target AChE (including active and inhibited) is captured onto the electrode surface and followed by an electrochemical detection of enzymatic activity in the presence of acetylthiocholine. A linear response is obtained over standard AChE concentration range from 0.1 to 10 nM. To demonstrate the capability of this new biomonitoring method, AChE solutions dosed with different concentration of paraoxon were used to validate the new AChE assay method. AChE inhibition in OP dosed solutions was proportional to its concentration from 0.2 to 50 nM. The new AChE activity assay method for biomonitoring of OP exposure was further validated with in-vitro paraoxon-dosed RBC samples. The established electrochemical sensing platform for AChE activity assay not only avoids the problem of overlapping substrate specificity with esterases by using selective antibody, but also eliminates potential interference from other electroactive species in biological samples. It offers a new approach for sensitive, selective, and rapid AChE activity assay for biomonitoring of exposures to OPs.

  2. Determination of oxygen saturation of the optic nerve head and overlying artery and vein using a snapshot multi-spectral imaging system

    NASA Astrophysics Data System (ADS)

    Khoobehi, Bahram; Eaton, Alexander; Wafapoor, Hussein; Fournier, Paul; Firn, Kim; Peters, Matt; Rodebeck, Ellie; Templet, Brian

    2012-03-01

    We have developed a snapshot optical imaging system capable of taking multiple images simultaneously and sending them to a CCD detector. Using an innovative lens array design, the beam obtained from the fundus camera is segmented into several different images passed through several different bandpass filters. Each bandpass filter defines a unique spectral region of imaging. The images are taken simultaneously into a large silicone chip with a dynamic range of 16 bits (highly sensitive) and are integrated with a single optical connection to a digital fundus camera. Our algorithm maps blood oxygen saturation of the retina using several wavelengths. These wavelengths are capable of approximating the whole hemoglobin spectrum and have been found from a previously developed hyperspectral algorithm. They include four isosbestic points (522, 548, 569, and 586 nm) and three oxygen-sensitive points (542, 560, and 586 nm) where the difference between fully oxygenated and deoxygenated blood is at a maximum. Using MatLab code, color maps of oxygen saturation are produced. The average value taken from all vein areas was 60.53%, assuming that the artery oxygen saturation value is 98%. Oxygen saturation of the tissue was 75.78%. Oxygen saturations of the temporal/inferior/nasal veins ranged from 61.86% to 63.37%; the superior vein was significantly lower (54.19%). Tissue oxygen saturations in different quadrants of the eye ranged from 74.17% to 76.74%. Our algorithm has been developed for measuring oxygen saturation of the retina clinically. This was done for one subject only; further work can extend the measurements to different pigments.

  3. Dynamic changes in the distribution and time course of blood-brain barrier-permeative nitroxides in the mouse head with EPR imaging: visualization of blood flow in a mouse model of ischemia.

    PubMed

    Emoto, Miho C; Sato-Akaba, Hideo; Hirata, Hiroshi; Fujii, Hirotada G

    2014-09-01

    Electron paramagnetic resonance (EPR) imaging using nitroxides as redox-sensitive probes is a powerful, noninvasive method that can be used under various physiological conditions to visualize changes in redox status that result from oxidative damage. Two blood-brain barrier-permeative nitroxides, 3-hydroxymethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (HMP) and 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy (MCP), have been widely used as redox-sensitive probes in the brains of small animals, but their in vivo distribution and properties have not yet been analyzed in detail. In this study, a custom-made continuous-wave three-dimensional (3D) EPR imager was used to obtain 3D EPR images of mouse heads using MCP or HMP. This EPR imager made it possible to take 3D EPR images reconstructed from data from 181 projections acquired every 60s. Using this improved EPR imager and magnetic resonance imaging, the distribution and reduction time courses of HMP and MCP were examined in mouse heads. EPR images of living mice revealed that HMP and MCP have different distributions and different time courses for entering the brain. Based on the pharmacokinetics of the reduction reactions of HMP and MCP in the mouse head, the half-lives of HMP and MCP were clearly and accurately mapped pixel by pixel. An ischemic mouse model was prepared, and the half-life of MCP was mapped in the mouse head. Compared to the half-life in control mice, the half-life of MCP in the ischemic model mouse brain was significantly increased, suggesting a shift in the redox balance. This in vivo EPR imaging method using BBB-permeative MCP is a useful noninvasive method for assessing changes in the redox status in mouse brains under oxidative stress.

  4. Early Prediction of Outcome in Advanced Head-and-Neck Cancer Based on Tumor Blood Volume Alterations During Therapy: A Prospective Study

    SciTech Connect

    Cao Yue Popovtzer, Aron; Li, Diana; Chepeha, Douglas B.; Moyer, Jeffrey S.; Prince, Mark E.; Worden, Francis; Teknos, Theodoros; Bradford, Carol; Mukherji, Suresh K.; Eisbruch, Avraham

    2008-12-01

    Purpose: To assess whether alterations in tumor blood volume (BV) and blood flow (BF) during the early course of chemo-radiotherapy (chemo-RT) for head-and-neck cancer (HNC) predict treatment outcome. Methods and Materials: Fourteen patients receiving concomitant chemo-RT for nonresectable, locally advanced HNC underwent dynamic contrast-enhanced (DCE) MRI scans before therapy and 2 weeks after initiation of chemo-RT. The BV and BF were quantified from DCE MRI. Preradiotherapy BV and BF, as well as their changes during RT, were evaluated separately in the primary gross tumor volume (GTV) and nodal GTV for association with outcomes. Results: At a median follow-up of 10 months (range, 5-27 months), 9 patients had local-regional controlled disease. One patient had regional failure, 3 had local failures, and 1 had local-regional failure. Reduction in tumor volume after 2 weeks of chemo-RT did not predict for local control. In contrast, the BV in the primary GTV after 2 weeks of chemo-RT was increased significantly in the local control patients compared with the local failure patients (p < 0.03). Conclusions: Our data suggest that an increase in available primary tumor blood for oxygen extraction during the early course of RT is associated with local control, thus yielding a predictor with potential to modify treatment. These findings require validation in larger studies.

  5. An accurate method for microanalysis of carbon monoxide in putrid postmortem blood by head-space gas chromatography-mass spectrometry (HS/GC/MS).

    PubMed

    Hao, Hongxia; Zhou, Hong; Liu, Xiaopei; Zhang, Zhong; Yu, Zhongshan

    2013-06-10

    Carbon monoxide (CO) may be the cause of more than half the fatal poisonings reported in many countries, with some of these cases under-reported or misdiagnosed by medical professionals. Therefore, an accurate and reliable analytical method to measure blood carboxyhemoglobin level (COHb%), in the 1% to lethal range, is essential for correct diagnosis. Herein a method was established, i.e. head-space gas chromatography-mass spectrometry (HS/GC/MS) that has numerous advantages over other techniques, such as UV spectrometry, for determination of COHb%. There was a linear relationship (R(2)=0. 9995) between the peak area for CO and the COHb% in blood. Using a molecular sieve-packed column, CO levels in the air down to 0.01% and COHb% levels in small blood samples down to 0.2% could be quantitated rapidly and accurately. Furthermore, this method showed good reproducibility with a relative standard deviation for COHb% of <1%. Therefore, this technique provides an accurate and reliable method for determining CO and COHb% levels and may prove useful for investigation of deaths potentially related to CO exposure.

  6. Fracture of skull base with delayed multiple cranial nerve palsies.

    PubMed

    Yildirim, Altan; Gurelik, Mustafa; Gumus, Cesur; Kunt, Tanfer

    2005-07-01

    This report describes a pediatric case of delayed glossopharyngeal nerve, vagus nerve, and facial nerve palsies after a head injury. Computed tomography scan of the skull base revealed the fracture of the petrous part of the temporal bone, and the fracture involved the tip of petrous pyramid, in front of the jugular foramen. The anatomical features, mechanisms, diagnosis, and treatment are discussed.

  7. Microsurgical anatomy of the trigeminal nerve.

    PubMed

    Joo, Wonil; Yoshioka, Fumitaka; Funaki, Takeshi; Mizokami, Koji; Rhoton, Albert L

    2014-01-01

    The objective of this study is to review surgical anatomy of the trigeminal nerve. We also demonstrate some pictures involving the trigeminal nerve and its surrounding connective and neurovascular structures. Ten adult cadaveric heads were studied, using a magnification ranging from 3× to 40×, after perfusion of the arteries and veins with colored latex. The trigeminal nerve is the largest and most complex of the cranial nerves. It serves as a major conduit of sensory input from the face and provides motor innervation to the muscles of mastication. Because of its size and complexity, it is essential to have thorough knowledge of the nerve before diagnoses and treatment of the pathologic processes in the orofacial, temporomandibular, infratemporal, and pterygopalatine areas. The trigeminal nerve is encountered with imaging or surgery of the skull base surgery. Thus, a comprehensive knowledge of the anatomy of the trigeminal nerve is crucial for performing the surgical procedures without significant complication.

  8. Overview of Head Injuries

    MedlinePlus

    ... appear to be more serious than it is. Did You Know... Because the scalp has many blood ... these symptoms occur, prompt medical attention is essential. Did You Know... The degree of external head injury ...

  9. Analysis by NASA's VESGEN Software of Retinal Blood Vessels in Human Subjects Undergoing Head-Down Tilt During 70-Day Bed Rest

    NASA Technical Reports Server (NTRS)

    Vyas, Ruchi J.; Murray, Matthew C.; Predovic, Marina; Lim, Shiyin; Askin, Kayleigh N.; Vizzeri, Gianmarco; Taibbi, Giovanni; Mason, Sara Stroble; Zanello, Susana B.; Young, Millenia; Parsons-Wingerter, Patricia

    2017-01-01

    Significant risks for visual impairment associated with increased intracranial pressure (VIIP) are incurred by microgravity spaceflight, especially long-duration missions [1]. We hypothesize that microgravity-induced fluid shifts result in pathological changes within blood vessels of the retina that precede development of visual and other ocular impairments. Potential contributions of retinal vascular remodeling to VIIP etiology are therefore being investigated for two studies in 30deg infrared (IR) Heidelberg Spectralis(Registered Trademark) images with NASA's innovative VESsel GENeration Analysis (VESGEN) software [2,3]. The retrospective studies include: (1) before, during and after (pre, mid and post) 6º head-down tilt (HDT) in human subjects during 70 days of bed rest, and (2) before and after missions to the International Space Station (ISS) by U.S. crew members. Results for both studies are almost complete. A preliminary example for HDT is described below.

  10. Viscosity-adjusted estimation of pressure head and pump flow with quasi-pulsatile modulation of rotary blood pump for a total artificial heart.

    PubMed

    Yurimoto, Terumi; Hara, Shintaro; Isoyama, Takashi; Saito, Itsuro; Ono, Toshiya; Abe, Yusuke

    2016-09-01

    Estimation of pressure and flow has been an important subject for developing implantable artificial hearts. To realize real-time viscosity-adjusted estimation of pressure head and pump flow for a total artificial heart, we propose the table estimation method with quasi-pulsatile modulation of rotary blood pump in which systolic high flow and diastolic low flow phased are generated. The table estimation method utilizes three kinds of tables: viscosity, pressure and flow tables. Viscosity is estimated from the characteristic that differential value in motor speed between systolic and diastolic phases varies depending on viscosity. Potential of this estimation method was investigated using mock circulation system. Glycerin solution diluted with salty water was used to adjust viscosity of fluid. In verification of this method using continuous flow data, fairly good estimation could be possible when differential pulse width modulation (PWM) value of the motor between systolic and diastolic phases was high. In estimation under quasi-pulsatile condition, inertia correction was provided and fairly good estimation was possible when the differential PWM value was high, which was not different from the verification results using continuous flow data. In the experiment of real-time estimation applying moving average method to the estimated viscosity, fair estimation could be possible when the differential PWM value was high, showing that real-time viscosity-adjusted estimation of pressure head and pump flow would be possible with this novel estimation method when the differential PWM value would be set high.

  11. Vagus nerve stimulation regulates hemostasis in swine.

    PubMed

    Czura, Christopher J; Schultz, Arthur; Kaipel, Martin; Khadem, Anna; Huston, Jared M; Pavlov, Valentin A; Redl, Heinz; Tracey, Kevin J

    2010-06-01

    The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical stimulation of the vagus nerve suppresses proinflammatory cytokine release in response to endotoxin, I/R injury, and hypovolemic shock and protects against lethal hypotension. To determine the effect of vagus nerve stimulation on coagulation pathways, anesthetized pigs were subjected to partial ear resection before and after electrical vagus nerve stimulation. We observed that electrical vagus nerve stimulation significantly decreased bleeding time (pre-electrical vagus nerve stimulation = 1033 +/- 210 s versus post-electrical vagus nerve stimulation = 585 +/- 111 s; P < 0.05) and total blood loss (pre-electrical vagus nerve stimulation = 48.4 +/- 6.8 mL versus post-electrical vagus nerve stimulation = 26.3 +/- 6.7 mL; P < 0.05). Reduced bleeding time after vagus nerve stimulation was independent of changes in heart rate or blood pressure and correlated with increased thrombin/antithrombin III complex generation in shed blood. These data indicate that electrical stimulation of the vagus nerve attenuates peripheral hemorrhage in a porcine model of soft tissue injury and that this protective effect is associated with increased coagulation factor activity.

  12. Peripapillary Retinal Nerve Fiber Layer Vascular Microcirculation in Glaucoma Using Optical Coherence Tomography–Based Microangiography

    PubMed Central

    Chen, Chieh-Li; Zhang, Anqi; Bojikian, Karine D.; Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.; Wang, Ruikang K.

    2016-01-01

    Purpose To investigate the vascular microcirculation changes in the retinal nerve fiber layer (RNFL) in normal, glaucoma suspect, and open-angle glaucoma (OAG) groups using optical coherence tomography–based microangiography (OMAG). Methods One eye from each subject was scanned with a Cirrus HD-OCT 5000–based OMAG prototype system montage scanning protocol centered at the optic nerve head (ONH). Blood flow signals were extracted using OMAG algorithm. Retinal nerve fiber layer vascular microcirculation was measured by calculating the blood flux index and vessel area density within a 1.2-mm width annulus centered at the ONH with exclusion of big retinal vessels. One-way ANOVA were performed to analyze the RNFL microcirculation among groups. Linear-regression models were constructed to analyze the correlation between RNFL microcirculation and clinical parameters. Discrimination capabilities of the flow metrics were assessed with the area under the receiver operating characteristic curve (AROC). Results Twenty normal, 26 glaucoma suspect, and 42 OAG subjects were enrolled. Eyes from OAG subjects and glaucoma suspects showed significantly lower blood flux index compared with normal eyes (P ≤ 0.0015). Retinal nerve fiber layer blood flow metrics showed significant correlations with visual field indices and structural changes in glaucomatous eyes (P ≤ 0.0123). Similar discrimination capability of blood flux index compared with RNFL thickness was found in both disease groups. Conclusions Peripapillary RNFL vascular microcirculation measured as blood flux index by OMAG showed significant differences among OAG, glaucoma suspect, and normal controls and was significantly correlated with functional and structural defects. Retinal nerve fiber layer microcirculation measurement using OMAG may help physicians monitor glaucoma. PMID:27442341

  13. Nerve Blocks

    MedlinePlus

    ... Sometimes the needle has to be inserted fairly deep to reach the nerve causing your problem. This ... understanding of the possible charges you will incur. Web page review process: This Web page is reviewed ...

  14. The use of rapid and cost-effective blood-based biomarkers in combination with tumour TNM stage for individual head and neck cancer patient treatment selection.

    PubMed

    Laytragoon Lewin, Nongnit; Lewin, Freddi; Andersson, Bengt-Åke; Löfgren, Sture; Rutqvist, Lars Erik

    2017-04-01

    Head and neck (H&N) cancer is an aggressive disease and the incidence has increased in younger population worldwide. Tumour TNM staging is the main basis for treatment decision despite significant variation in clinical outcome. Survival time of these patients has marginally improved during the last 30 years. Various biomarkers with cumbersome analysis, high cost, time consumption and requirement of special laboratory facilities have been investigated. However, none of these biomarkers have been shown to be suitable to use for individual H&N cancer patient treatment selection in the clinic. For practical use in clinical settings, the given biomarkers must be simple to analyse, rapid, cost effective and available in routine laboratories. With this intension, we suggested the combination of standard TNM staging and biomarkers associated with inflammation such as neutrophils, neutrophil to lymphocyte ratio, plasma C-reactive protein or plasma tumour necrosis factor alpha (TNFa) and single-nucleotide polymorphism in TNFa rs1800629 using blood-based analysis. The optimal treatment outcome of H&N cancer by using combination of TNM stage and these blood-based biomarkers for individual patient selection need further investigation.

  15. Ivermectin acts as a posteclosion nymphicide by reducing blood feeding of human head lice (Anoplura: Pediculidae) that hatched from treated eggs.

    PubMed

    Strycharz, Joseph P; Berge, Noah M; Alves, Anna-Maria; Clark, J Marshall

    2011-11-01

    The 0.5% ivermectin topical cream formulation was not directly ovicidal to treated eggs of head lice, as hatchability was not decreased. Nevertheless, the percent of hatched lice from treated eggs that took a blood meal significantly decreased (80-95%) compared with lice that hatched from untreated eggs and all treated lice died within 48 h of hatching, including those that fed. Dilutions of ivermectin formulation of 0.15 and 0.2 microg/ml, which were topically applied to 0-8 d old eggs, were not lethal to lice at 24 h posteclosion. However, 9 and 16% less lice fed when hatched from these treated eggs, respectively. Total [3H] inulin ingested by untreated first instars significantly increased over a 48 h feeding interval but was significantly less in instars that hatched from eggs receiving the 0.15 (36% less) and 0.2 (55% less) microg/ml ivermectin treatments compared with placebo. The reduced feeding that occurred after the 0.15 and 0.2 microg/ml ivermectin treatments occurred in the absence of mortality and suggests a unique mode of action of ivermectin on feeding that is separate from the mode of action of ivermectin leading to mortality. Failure of hatched instars to take a blood meal after egg treatments with formulated ivermectin is likely responsible for its action as a posteclosion nymphicide.

  16. Blood

    MedlinePlus

    ... increased red blood cell destruction can affect teens: G6PD deficiency. G6PD is an enzyme that helps to protect ... can cause red cells to hemolyze, or burst. G6PD deficiency is a common hereditary disease among people of ...

  17. Behavioural and psychosocial sequelae of severe closed head injury and regional cerebral blood flow: a SPECT study.

    PubMed Central

    Oder, W; Goldenberg, G; Spatt, J; Podreka, I; Binder, H; Deecke, L

    1992-01-01

    Thirty six patients (31 male, 5 female) who had suffered severe closed head injury were re-examined at an average of 39.3 (SD 12.8, range 7-66) months after the injury. Behavioural symptoms were measured using the Giessen test. The relatives' reports were used for data analysis to ensure that results were valid. The neurophysical impairment subscale of the Glasgow assessment schedule was completed by two neurologists, and the number connection test was completed by each patient. The adjective mood scale was completed by each relative. All patients were investigated by single photon emission computerised tomography (SPECT). Exploratory factor analysis using the principal components method was carried out separately for SPECT results and psychological measures and correlations were sought between the resulting factors. Factor analysis of the data from the Giessen test identified social isolation, disinhibition, and aggressive behaviour as major components of post-traumatic personality changes; it indicates that these behavioural features are independent of the level of neurological and neuropsychological impairment, which loaded on a single independent factor. Relatives' psychic health seemed to be relatively resistant to physical and cognitive disability and was mainly affected by disinhibitive behaviour. The highest correlation was between frontal flow indices and disinhibitive behaviour (p less than 0.01): the severity of disinhibition increased with lower frontal flow rates. There was a significant but somewhat weaker correlation (p less than 0.05) between flow indices of the left cerebral hemisphere and social isolation. Low flow values of the right brain regions were related to aggressive behaviour (p less than 0.05). Neurological and cognitive impairment correlated negatively with the thalamus; worse neurological and cognitive performance indicate by raised scores on the neurophysical scale and on the number connection test was associated with low thalamic

  18. Evaluation of the in vivo genotoxic effects of gamma radiation on the peripheral blood leukocytes of head and neck cancer patients undergoing radiotherapy.

    PubMed

    Kadam, Samit B; Shyama, Soorambail K; Almeida, Valentine G

    2013-04-15

    The present study aimed to evaluate the genotoxic effects of ionizing radiation on non-target cells of Head and Neck Squamous Cell Carcinoma (HNSCC) patients exposed to various cumulative doses of gamma rays during radiotherapy. The ten patients (P1-P10) were treated with cobalt 60 gamma radiation (External Beam Radiotherapy) for a period of five to six weeks with a daily fraction of 2Gy for 5 days each week. The genotoxic effects of radiation (single strand breaks - SSBs) in these patients were analyzed using the alkaline single cell gel electrophoresis (SCGE) technique, with the Olive Tail Moment (OTM) as the critical parameter. A sample of each patient's peripheral blood before starting with radiotherapy (pre-therapy) served as the control, and blood collected at weekly time intervals during the course of the radiotherapy served as treated (10, 20, 30, 40, 50 and 60Gy) samples. In vivo radiosensitivity of these patients, as indicated by SSB's after the cumulative radiation doses at the various times, was assessed using Student's t-test. Significant DNA damage relative to the individual patient's pre-therapy baseline data was observed in all patients. Inter-individual variation of the genotoxic effects was analyzed using two-way ANOVA. The correlation between doses for the means of smoker and non-smoker patients was calculated using the Pearson test. The results of this study may indicate the need to reduce the daily radiotherapy dose further to prevent genotoxic effects on non-target cells, thus improving safety. Furthermore, these results may indicate that the estimation of DNA damage following exposure to a gamma radiation, as measured by the comet assay in whole blood leukocytes, can be used to screen human populations for radiation-induced genetic damage at the molecular level.

  19. Rehabilitation of the trigeminal nerve

    PubMed Central

    Iro, Heinrich; Bumm, Klaus; Waldfahrer, Frank

    2005-01-01

    When it comes to restoring impaired neural function by means of surgical reconstruction, sensory nerves have always been in the role of the neglected child when compared with motor nerves. Especially in the head and neck area, with its either sensory, motor or mixed cranial nerves, an impaired sensory function can cause severe medical conditions. When performing surgery in the head and neck area, sustaining neural function must not only be highest priority for motor but also for sensory nerves. In cases with obvious neural damage to sensory nerves, an immediate neural repair, if necessary with neural interposition grafts, is desirable. Also in cases with traumatic trigeminal damage, an immediate neural repair ought to be considered, especially since reconstructive measures at a later time mostly require for interposition grafts. In terms of the trigeminal neuralgia, commonly thought to arise from neurovascular brainstem compression, a pharmaceutical treatment is considered as the state of the art in terms of conservative therapy. A neurovascular decompression of the trigeminal root can be an alternative in some cases when surgical treatment is sought after. Besides the above mentioned therapeutic options, alternative treatments are available. PMID:22073060

  20. Optic Nerve Decompression

    MedlinePlus

    ... Nerve Decompression Dacryocystorhinostomy (DCR) Disclosure Statement Printer Friendly Optic Nerve Decompression John Lee, MD Introduction Optic nerve decompression is a surgical procedure aimed at ...

  1. Ulnar nerve dysfunction

    MedlinePlus

    Neuropathy - ulnar nerve; Ulnar nerve palsy; Mononeuropathy; Cubital tunnel syndrome ... compressed in the elbow, a problem called cubital tunnel syndrome may result. When damage destroys the nerve ...

  2. Transient unilateral combined paresis of the hypoglossal nerve and lingual nerve following intubation anesthesia.

    PubMed

    Ulusoy, Hulya; Besir, Ahmet; Cekic, Bahanur; Kosucu, Muge; Geze, Sukran

    2014-01-01

    Nerve damage may occur in the pharyngolaryngeal region during general anesthesia. The most frequently injured nerves are the hypoglossal, lingual and recurrent laryngeal. These injuries may arise in association with several factors, such as laryngoscopy, endotracheal intubation and tube insertion, cuff pressure, mask ventilation, the triple airway maneuver, the oropharyngeal airway, manner of intubation tube insertion, head and neck position and aspiration. Nerve injuries in this region may take the form of an isolated single nerve or of paresis of two nerves together in the form of hypoglossal and recurrent laryngeal nerve palsy (Tapia's syndrome). However, combined injury of the lingual and hypoglossal nerves following intubation anesthesia is a much rarer condition. The risk of this damage can be reduced with precautionary measures. We describe a case of combined unilateral nervus hypoglossus and nervus lingualis paresis developing after intubation anesthesia.

  3. Physical and Psychological Effects of Head Treatment in the Supine Position Using Specialized Ayurveda-Based Techniques

    PubMed Central

    Iwawaki, Yoko; Uebaba, Kazuo; Yamamoto, Yoko; Takishita, Yukie; Harada, Kiyomi; Shibata, Akemi; Narumoto, Jin; Fukui, Kenji

    2016-01-01

    Abstract Objective: To clarify the physical and psychological effects of head massage performed in the supine position using Ayurveda-based techniques (head treatment). Design: Twenty-four healthy female students were included in the study. Using a crossover study design, the same participants were enrolled in both the head treatment intervention group and control group. There was an interval of 1 week or more between measurements. Outcome measures: The physiologic indices measured included blood pressure and heart rate fluctuations (high frequency and low frequency/high frequency). The psychological markers measured included liveliness, depression, and boredom using the visual analogue scale method. State anxiety was measured using the State-Trait Anxiety Inventory method. Results: The parasympathetic nerve activity increased immediately after head treatment. Upon completion of head treatment, the parasympathetic nerve predominance tended to gradually ease. Head treatment boosted freshness and relieved anxiety. Conclusions: The results suggest that head treatment has a relaxing and refreshing effect and may be used to provide comfort. PMID:27163344

  4. Head Lice

    MedlinePlus

    ... Schedules Nutrient Shortfall Questionnaire Home Diseases and Conditions Head Lice Head Lice Condition Family HealthKids and Teens Share Head Lice Table of Contents1. Overview2. Symptoms3. Causes4. Prevention5. ...

  5. Upper limb reinnervation in C6 tetraplegia using a triple nerve transfer: case report.

    PubMed

    van Zyl, Natasha; Hahn, Jodie B; Cooper, Catherine A; Weymouth, Michael D; Flood, Stephen J; Galea, Mary P

    2014-09-01

    Restoration of elbow extension, grasp, key pinch, and release are major goals in low-level tetraplegia. Traditionally, these functions are achieved using tendon transfers. In this case these goals were achieved using nerve transfers. We present a 21-year-old man with a C6 level of tetraplegia. The left upper limb was treated 6 months after injury with a triple nerve transfer. A teres minor nerve branch to long head of triceps nerve branch, brachialis nerve branch to anterior interosseous nerve, and supinator nerve branch to posterior interosseous nerve transfer were used successfully to reconstruct elbow extension, key pinch, grasp, and release simultaneously.

  6. Vagus Nerve Stimulation

    MedlinePlus

    Vagus nerve stimulation Overview By Mayo Clinic Staff Vagus nerve stimulation is a procedure that involves implantation of a device that stimulates the vagus nerve with electrical impulses. There's one vagus nerve on ...

  7. Nerve biopsy (image)

    MedlinePlus

    Nerve biopsy is the removal of a small piece of nerve for examination. Through a small incision, a sample ... is removed and examined under a microscope. Nerve biopsy may be performed to identify nerve degeneration, identify ...

  8. In vitro effects of metals on isolated head-kidney and blood leucocytes of the teleost fish Sparus aurata L. and Dicentrarchus labrax L.

    PubMed

    Morcillo, Patricia; Meseguer, José; Esteban, M Ángeles; Cuesta, Alberto

    2016-07-01

    The in vitro use of fish leucocytes to test the toxicity of aquatic pollutants, and particularly the immutoxicological effects, could be a valuable alternative to fish bioassays but has received little attention. In this study, head-kidney and peripheral blood leucocytes (HKLs and PBLs, respectively) from gilthead seabream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.) specimens were exposed to Cd, MeHg (methylmercury), Pb or As for 24 h being evaluated the resulting cytotoxicity. Exposure to metals produced a dose-dependent reduction in the viability, and MeHg showed the highest toxicity followed by Cd, As and Pb. Interestingly, leucocytes from European sea bass are more resistant to metal exposure than those from gilthead seabream. Similarly, HKLs are always more sensitive than those isolated from blood from the same fish species. Moreover, fish leucocytes incubated with metals exhibited alterations in gene expression profiles that were more pronounced in the HKLs in general, being Pb the metal provoking less effects. Concretely, genes related to cellular protection (metallothionein), stress (heat shock protein 70) and oxidative stress (superoxide dismutase, catalase and glutathione reductase) were, in general, down-regulated in seabream HKLs but up-regulated in seabream PBLs and sea bass HKLs and PBLs. In addition, this profile leads to the increase of expression in genes related to apoptosis (Bcl2 associated X protein and caspase 3). Finally, transcription of genes involved in immunity (interleukin-1β and immunoglobulin M) was down-regulated, mainly in seabream leucocytes. This study points to the benefits for evaluating the toxicological mechanisms of marine pollution using fish leucocytes in vitro and insight into the mechanisms at gene level.

  9. Microsurgical anatomy of the ocular motor nerves.

    PubMed

    Zhang, Yi; Liu, Hao; Liu, En-Zhong; Lin, You-Zhi; Zhao, Shi-Guang; Jing, Guo-Hua

    2010-08-01

    This study was designed to provide anatomic data to help surgeons avoid damage to the ocular motor nerves during intraorbital operations. The microsurgical anatomy of the ocular motor nerves was studied in 50 adult cadaveric heads (100 orbits). Dissections were performed with a microscope. The nerves were exposed and the neural and muscular relationships of each portion of the nerve were examined and measured. The superior division of the oculomotor nerve coursed between the optic nerve and the superior rectus muscle after it left the annular tendon, and its branches entered into the superior rectus muscle and levator muscle. A mean of five fibers (range 3-7) innervated the superior rectus muscle, and a mean of one fiber (range 1-2) followed a medial direction (84%) or went straight through the superior rectus muscle (16%). The inferior division of the oculomotor nerve branched into the medial rectus, inferior rectus and inferior oblique muscles. The trochlear nerve ended on the orbital side of the posterior one-third of the superior oblique muscle in 76 specimens. The abducens nerve ended on the posterior one-third of the lateral rectus muscle in 86 specimens. If the belly of the lateral rectus muscle was divided into three superior-inferior parts, the nerve commonly entered into the middle one-third in 74 specimens. Based on the observed data, microanatomical relationships of the orbital contents were revised.

  10. Vitamin K2 Ameliorates Damage of Blood Vessels by Glucocorticoid: a Potential Mechanism for Its Protective Effects in Glucocorticoid-induced Osteonecrosis of the Femoral Head in a Rat Model

    PubMed Central

    Zhang, Yuelei; Yin, Junhui; Ding, Hao; Zhang, Changqing; Gao, You-Shui

    2016-01-01

    Glucocorticoid has been reported to decrease blood vessel number and harm the blood supply in the femoral head, which is recognized to be an important mechanism of glucocorticoid-induced osteonecrosis of the femoral head (ONFH). To prevent glucocorticoid-induced ONFH, medication that promotes both bone formation and angiogenesis would be ideal. Vitamin K2 has been revealed to play an important role in bone metabolism; however, few studies have focused on the effect of Vitamin K2 on new vascular formation. Thus, this study aimed to investigate whether Vitamin K2 promoted new blood vessel formation in the presence of glucocorticoids, both in vitro and in vivo. The effect of Vitamin K2 on viability, migration, in vitro tube formation, and VEGF, vWF, CD31, KDR, Flt and PDGFB in EAhy926 incubated with or without dexamethasone were elucidated. VEGF, TGF-β and BMP-2, angiogenesis-related proteins secreted by osteoblasts, were also detected in the osteoblast-like cell line of MG63. In addition, blood vessels of the femoral head in rats administered with or without methylprednisolone and Vitamin K2 were evaluated using angiography and CD31 staining. In vitro studies showed that Vitamin K2 significantly protected endothelial cells from dexamethasone-induced apoptosis, promoted endothelial cell migration and in vitro tube formation. Angiogenesis-related proteins both in EAhy926 and MG63 were also upregulated by Vitamin K2 when cotreated with dexamethasone. In vivo studies showed enhanced blood vessel volume and CD31-positive staining cells in rats cotreated with VK2 and methylprednisolone compared to rats treated with methylprednisolone only. Collectively, Vitamin K2 has the ability to promote angiogenesis in vitro and to ameliorate vessels of the femoral head in glucocorticoid-treated rats in vivo, indicating that Vitamin K2 is a promising drug that may be used to prevent steroid-induced ONFH. PMID:27313492

  11. Optic Nerve.

    PubMed

    Gordon, Lynn K

    2016-10-28

    Optic nerve diseases arise from many different etiologies including inflammatory, neoplastic, genetic, infectious, ischemic, and idiopathic. Understanding some of the characteristics of the most common optic neuropathies along with therapeutic approaches to these diseases is helpful in designing recommendations for individual patients. Although many optic neuropathies have no specific treatment, some do, and it is those potentially treatable or preventable conditions which need to be recognized in order to help patients regain their sight or develop a better understanding of their own prognosis. In this chapter several diseases are discussed including idiopathic intracranial hypertension, optic neuritis, ischemic optic neuropathies, hereditary optic neuropathies, trauma, and primary tumors of the optic nerve. For each condition there is a presentation of the signs and symptoms of the disease, in some conditions the evaluation and diagnostic criteria are highlighted, and where possible, current therapy or past trials are discussed.

  12. Hemodynamic response to exercise and head-up tilt of patients implanted with a rotary blood pump: a computational modeling study.

    PubMed

    Lim, Einly; Salamonsen, Robert Francis; Mansouri, Mahdi; Gaddum, Nicholas; Mason, David Glen; Timms, Daniel L; Stevens, Michael Charles; Fraser, John; Akmeliawati, Rini; Lovell, Nigel Hamilton

    2015-02-01

    The present study investigates the response of implantable rotary blood pump (IRBP)-assisted patients to exercise and head-up tilt (HUT), as well as the effect of alterations in the model parameter values on this response, using validated numerical models. Furthermore, we comparatively evaluate the performance of a number of previously proposed physiologically responsive controllers, including constant speed, constant flow pulsatility index (PI), constant average pressure difference between the aorta and the left atrium, constant average differential pump pressure, constant ratio between mean pump flow and pump flow pulsatility (ratioP I or linear Starling-like control), as well as constant left atrial pressure ( P l a ¯ ) control, with regard to their ability to increase cardiac output during exercise while maintaining circulatory stability upon HUT. Although native cardiac output increases automatically during exercise, increasing pump speed was able to further improve total cardiac output and reduce elevated filling pressures. At the same time, reduced venous return associated with upright posture was not shown to induce left ventricular (LV) suction. Although P l a ¯ control outperformed other control modes in its ability to increase cardiac output during exercise, it caused a fall in the mean arterial pressure upon HUT, which may cause postural hypotension or patient discomfort. To the contrary, maintaining constant average pressure difference between the aorta and the left atrium demonstrated superior performance in both exercise and HUT scenarios. Due to their strong dependence on the pump operating point, PI and ratioPI control performed poorly during exercise and HUT. Our simulation results also highlighted the importance of the baroreflex mechanism in determining the response of the IRBP-assisted patients to exercise and postural changes, where desensitized reflex response attenuated the percentage increase in cardiac output during exercise and

  13. In Vivo Reactivation by Oximes of Inhibited Blood, Brain and Peripheral Tissue Cholinesterase Activity Following Exposure to Nerve Agents in Guinea Pigs

    DTIC Science & Technology

    2010-01-01

    nerve agent intoxication ( salivation , rhinorrhea, tremors,muscle asciculations, convulsions) at 60min following the 1.0× LD50 dose f GB, GF, VR or VX...reactivation of GF-, soman-, or VR-inhibited enzyme byHI-6 andHLö7. However, these in vitro experiments [24,25] were conducted with a pH of 8.0 at 25 ◦C...data. Even the study of Worek et al. [23] that was performed at a pH of 7.4 at 37 ◦C, whose in vitro kinetic data obtained from guinea pig RBC ghosts

  14. Deficient nitric oxide responsible for reduced nerve blood flow in diabetic rats: effects of L-NAME, L-arginine, sodium nitroprusside and evening primrose oil.

    PubMed Central

    Omawari, N.; Dewhurst, M.; Vo, P.; Mahmood, S.; Stevens, E.; Tomlinson, D. R.

    1996-01-01

    1. This study examined the potential role of impaired nitric oxide production and response in the development of endoneurial ischaemia in experimental diabetes. Rats were anaesthetized (Na pentobarbitone 45 mg kg-1, diazepam 2 mg kg-1) for measurement of sciatic nerve laser Doppler flux and systemic arterial pressure. Drugs were administered into the sciatic endoneurium via a microinjector attached to a glass micropipette. 2. In two separate studies comparing diabetic rats (streptozotocin-induced; 8-10 wk duration) with controls, nerve Doppler flux in diabetic rats (Study 1, 116.6 +/- 40.4 and Study 2, 90.1 +/- 34.7 (s.d.) in arbitrary units) was about half that measured in controls (219.6 +/- 52.4 and 212.8 +/- 95.5 respectively; P < 0.005 for both). There were no significant differences between the two in systemic arterial pressure. 3. Inhibition of nitric oxide production by microinjection of 1 nmol L-NAME into the endoneurium halved flux in controls (to 126.3 +/- 41.3 in Study 1 and 102.1 +/- 38.9 in Study 2; both P < 0.001), with no significant effect in diabetic rats, indicating markedly diminished tonic nitric oxide production in the latter. D-NAME was without effect on nerve Doppler flux. 4. L-Arginine (100 nmol), injected after L-NAME, markedly increased flux in controls (by 65.8% (P < 0.03) and 97.8% (P < 0.01) in the two studies) and by proportionally similar amounts in diabetic rats [75.8% (P < 0.001) and 60.2% (P < 0.02)]. The nitro-donor, sodium nitroprusside (SNP; 10 nmol) had similar effects to L-arginine in both groups (increases of 66.0% in controls and 77.5% in diabetics; both P < 0.002). 5. A second diabetic group, treated with evening primrose oil performed exactly like control rats in respect of responses to L-NAME, L-arginine and SNP. 6. These findings implicate deficient nitric oxide in nerve ischaemia of diabetes and suggest correction thereof as a mechanism of action of evening primrose oil. PMID:8733594

  15. Ulnar nerve sonography in leprosy neuropathy.

    PubMed

    Wang, Zhu; Liu, Da-Yue; Lei, Yang-Yang; Yang, Zheng; Wang, Wei

    2016-01-01

    A 23-year-old woman presented with a half-year history of right forearm sensory and motor dysfunction. Ultrasound imaging revealed definite thickening of the right ulnar nerve trunk and inner epineurium, along with heterogeneous hypoechogenicity and unclear nerve fiber bundle. Color Doppler exhibited a rich blood supply, which was clearly different from the normal ulnar nerve presentation with a scarce blood supply. The patient subsequently underwent needle aspiration of the right ulnar nerve, and histopathological examination confirmed that granulomatous nodules had formed with a large number of infiltrating lymphocytes and a plurality of epithelioid cells in the fibrous connective tissues, with visible atypical foam cells and proliferous vascularization, consistent with leprosy. Our report will familiarize readers with the characteristic sonographic features of the ulnar nerve in leprosy, particularly because of the decreasing incidence of leprosy in recent years.

  16. Head MRI

    MedlinePlus

    ... the head; MRI - cranial; NMR - cranial; Cranial MRI; Brain MRI; MRI - brain; MRI - head ... the test, tell your provider if you have: Brain aneurysm clips An artificial heart valves Heart defibrillator ...

  17. Heads Up

    MedlinePlus

    ... Us HEADS UP Apps Reshaping the Culture Around Concussion in Sports Get HEADS UP on Your Web Site Concussion ... fit, and maintain the right helmet for specific sports. Concussion Laws Learn about Return to Play and other ...

  18. Long thoracic nerve injury.

    PubMed

    Wiater, J M; Flatow, E L

    1999-11-01

    Injury to the long thoracic nerve causing paralysis or weakness of the serratus anterior muscle can be disabling. Patients with serratus palsy may present with pain, weakness, limitation of shoulder elevation, and scapular winging with medial translation of the scapula, rotation of the inferior angle toward the midline, and prominence of the vertebral border. Long thoracic nerve dysfunction may result from trauma or may occur without injury. Fortunately, most patients experience a return of serratus anterior function with conservative treatment, but recovery may take as many as 2 years. Bracing often is tolerated poorly. Patients with severe symptoms in whom 12 months of conservative treatment has failed may benefit from surgical reconstruction. Although many surgical procedures have been described, the current preferred treatment is transfer of the sternal head of the pectoralis major tendon to the inferior angle of the scapula reinforced with fascia or tendon autograft. Many series have shown good to excellent results, with consistent improvement in function, elimination of winging, and reduction of pain.

  19. Head lice.

    PubMed

    Frankowski, Barbara L; Weiner, Leonard B

    2002-09-01

    Head lice infestation is associated with little morbidity but causes a high level of anxiety among parents of school-aged children. This statement attempts to clarify issues of diagnosis and treatment of head lice and makes recommendations for dealing with head lice in the school setting.

  20. Nerve conduction velocity

    MedlinePlus

    ... polyneuropathy Tibial nerve dysfunction Ulnar nerve dysfunction Any peripheral neuropathy can cause abnormal results. Damage to the spinal ... Herniated disk Lambert-Eaton syndrome Mononeuropathy Multiple ... azotemia Primary amyloidosis Radial nerve dysfunction Sciatica ...

  1. Nerve Impulses in Plants

    ERIC Educational Resources Information Center

    Blatt, F. J.

    1974-01-01

    Summarizes research done on the resting and action potential of nerve impulses, electrical excitation of nerve cells, electrical properties of Nitella, and temperature effects on action potential. (GS)

  2. Congenital anomalies of the optic nerve

    PubMed Central

    Amador-Patarroyo, Manuel J.; Pérez-Rueda, Mario A.; Tellez, Carlos H.

    2014-01-01

    Congenital optic nerve head anomalies are a group of structural malformations of the optic nerve head and surrounding tissues, which may cause congenital visual impairment and blindness. Each entity in this group of optic nerve anomalies has individually become more prevalent as our ability to differentiate between them has improved due to better characterization of cases. Access to better medical technology (e.g., neuroimaging and genetic analysis advances in recent years) has helped to expand our knowledge of these abnormalities. However, visual impairment may not be the only problem in these patients, some of these entities will be related to ophthalmologic, neurologic and systemic features that will help the physician to identify and predict possible outcomes in these patients, which sometimes may be life-threatening. Herein we present helpful hints, associations and management (when plausible) for them. PMID:25859137

  3. Bilateral high radial nerve compressions: a case report.

    PubMed

    Chuangsuwanich, A; Muangsombut, S; Sangruchi, T

    2000-06-01

    A 40-year-old woman with bilateral high radial nerve compressions by non-traumatic cause was reported. It occurred first at the right radial nerve which was explored after a period of investigation and conservative treatment. Two constricted sites 2.0 cm apart of the right radial nerve crossed by branches of the radial collateral artery beneath the lateral head of the triceps were found. The constricted sites including tissue in between was resected and replaced with a sural nerve graft. One year later the patient had the same episode on the left side. The operative finding was the same as the previous one. Sural nerve graft was performed after neurolysis had failed. The patient's normal radial nerve function returned in one year. This is the first reported case in the literature of bilateral high radial nerve compressions by branches of the radial collateral artery.

  4. Raman microspectroscopy for visualization of peripheral nerves

    NASA Astrophysics Data System (ADS)

    Minamikawa, Takeo; Harada, Yoshinori; Koizumi, Noriaki; Takamatsu, Tetsuro

    2013-02-01

    The peripheral nervous system plays an important role in motility, sensory, and autonomic functions of the human body. Preservation of peripheral nerves in surgery is essential for improving quality of life of patients. To preserve peripheral nerves, detection of ne peripheral nerves that cannot be identi ed by human eye or under white light imaging is necessary. In this study, we sought to provide a proof-of-principle demonstration of a label-free detection technique of peripheral nerve tissues against adjacent tissues that employs spontaneous Raman microspectroscopy. A line-illumination confocal Raman microscope was used for the experiment. A laser operating at the wavelength of 532 nm was used as an excitation laser light. We obtained Raman spectra of peripheral nerve, brous connective tissue, skeletal muscle, blood vessel, and adipose tissue of Wistar rats, and extracted speci c spectral features of peripheral nerves and adjacent tissues. By applying multivariate image analysis, peripheral nerves were clearly detected against adjacent tissues without any preprocessing neither xation nor staining. These results suggest the potential of the Raman spectroscopic observation for noninvasive and label-free nerve detection, and we expect this method could be a key technique for nerve-sparing surgery.

  5. Rhomboid nerve transfer to the suprascapular nerve for shoulder reanimation in brachial plexus palsy: A clinical report.

    PubMed

    Goubier, J-N; Teboul, F

    2016-10-01

    Recovery of shoulder function is a real challenge in cases of partial brachial plexus palsy. Currently, in C5-C6 root injuries, transfer of the long head of the triceps brachii branch is done to revive the deltoid muscle. Spinal accessory nerve transfer is typically used for reanimation of the suprascapular nerve. We propose an alternative technique in which the nerve of the rhomboid muscles is transferred to the suprascapular nerve. A 33-year-old male patient with a C5-C6 brachial plexus injury with shoulder and elbow flexion palsy underwent surgery 7 months after the injury. The rhomboid nerve was transferred to the suprascapular nerve and the long head of the triceps brachii branch to the axillary nerve for shoulder reanimation. A double transfer of fascicles was performed, from the ulnar and median nerves to the biceps brachii branch and brachialis branch, respectively, for elbow flexion. At 14 months' follow-up, elbow flexion was rated M4. Shoulder elevation was 85 degrees and rated M4, and external rotation was 80 degrees and rated M4. After performing a cadaver study showing that transfer of the rhomboid nerve to the suprascapular nerve is technically possible, here we report and discuss the clinical outcomes of this new transfer technique.

  6. Head Injuries

    MedlinePlus

    ... injury, cerebral contusion, cerebral laceration, coma, head trauma, hematoma, impaired consciousness, postconcussion syndrome, skull fracture, skull penetration, stupor, vegetative state Family Health, Infants ...

  7. Acquired myelinated nerve fibers in association with optic disk drusen.

    PubMed

    Duval, Renaud; Hammamji, Karim; Aroichane, Maryam; Michaud, Jacques L; Ospina, Luis H

    2010-12-01

    Myelinated retinal nerve fibers are a well-recognized anomaly of the ocular fundus associated with many ocular and systemic conditions. Myelination is almost always congenital and stable, but progression has been documented in rare cases. Optic disk drusen are the result of a degenerative process at the optic nerve head and are often found incidentally on ophthalmologic examination. To our knowledge, optic disk drusen have only been reported once in association with acquired and progressive myelinated retinal nerve fibers. We present 2 such cases and consider the implications for the pathogenesis of myelinated nerve fibers.

  8. Are sodium-dependent V1 receptors and sympathetic nerve activations involved in regulation of blood pressure in borderline-hypertensive Hiroshima rats?

    PubMed

    Teranishi, Yasuhiro; Kumazaki, Tsutomu; Miho, Narimasa; Sugino, Hiroshi; Tsuru, Hiromichi

    2002-09-01

    Sympathetic nerve activity (SNA) was estimated by the magnitude of depressor response after ganglionic blockade with hexamethonium bromide (C6; 25 mg/kg weight). The depressor effects of C6 were significantly less in borderline-hypertensive Hiroshima rats (BHR) than in deoxycorticosterone acetate (DOCA)-salt hypertensive rats (DOCA rats) or in spontaneously hypertensive rats (SHR), but they were not different in BHR and normotensive control Wistar rats (NCR). After sympatho-inhibition, the depressor effects of a selective vasopressin V1 receptor antagonist (V1A; 10 microg/kg: [d(CH2)5(1), O-Me-Tyr2, Arg8]-vasopressin) were significantly greater in BHR than in DOCA rats, SHR or NCR. In a previous study, we reported that the depressor effects of C6 were significantly less in BHR than in SHR, but after sympatho-inhibition, the depressor effects of V1A were significantly greater in BHR than in SHR (Hypertens Res 2002; 25: 241-248). After high-salt diet loading in the present study (8% salt-containing diet for 10 weeks), the magnitudes of increase in mean arterial pressure in BHR and NCR were almost the same. There was almost no difference in the depressor effects of V1A after sympatho-inhibition between BHR with high-salt intake and BHR without high-salt intake. The depressor effects of an angiotensin-converting enzyme inhibitor, captopril (1 mg/kg), were almost the same between BHR and NCR both before and after sympatho-inhibition. However, these effects were completely inhibited after the high-salt diet. The results show that SNA was within the normal range in BHR and that no further accelerated responsiveness of endogenous vasopressin was observed in BHR after high-salt intake.

  9. Adrenergic vasoconstriction in peripheral nerves of the rabbit

    SciTech Connect

    Selander, D.; Mansson, L.G.; Karlsson, L.; Svanvik, J.

    1985-01-01

    The blood flow in the sciatic nerve of the rabbit was estimated from the wash out of intraneurally injected /sup 133/Xe. To avoid diffusion of the tracer into the surrounding muscular tissue, the nerve was covered by a gas-tight plastic film. Using this technique, the basal blood flow in the sciatic nerve was estimated to 35 ml X min-1 X 100 g-1. It was found that intraarterial norepinephrine and electrical stimulation of the lumbar sympathetic chain strongly reduced the wash out of /sup 133/Xe, which only can be explained by a pronounced reduction of the blood flow in the nerve itself. The blood flow again increased within 4 min of stopping the infusion of norepinephrine or the sympathetic stimulation. The prolonged effect and higher neurotoxicity of local anesthetics containing adrenaline may be explained by an alpha receptor-mediated vasoconstriction of the microvessels of peripheral nerves.

  10. Pediatric head injury.

    PubMed

    Tulipan, N

    1998-01-01

    Pediatric head injury is a public health problem that exacts a high price from patients, their families and society alike. While much of the brain damage in head-injured patients occurs at the moment of impact, secondary injuries can be prevented by aggressive medical and surgical intervention. Modern imaging devices have simplified the task of diagnosing intracranial injuries. Recent advances in monitoring technology have made it easier to assess the effectiveness of medical therapy. These include intracranial pressure monitoring devices that are accurate and safe, and jugular bulb monitoring which provides a continuous, qualitative measure of cerebral blood flow. The cornerstones of treatment remain hyperventilation and osmotherapy. Despite maximal treatment, however, the mortality and morbidity associated with pediatric head injury remains high. Reduction of this mortality and morbidity will likely depend upon prevention rather than treatment.

  11. Laser welding of rat's facial nerve.

    PubMed

    Hwang, Kun; Kim, Sun Goo; Kim, Dae Joong; Lee, Chang Hyun

    2005-11-01

    The aim of this study is to compare regeneration of the severed nerves that were repaired by laser welding with those repaired by microsurgical suturing and evaluate the value in use of laser nerve welding in the head and neck area. In 12 rats the buccal branches of the facial nerves on the both sides were transected, and CO2 laser welding of the epineurium was performed on the right side and microsurgical suture technique was applied on the left side. In six rats Cholera Toxin B Subunit (CTb) was injected in the epineurium distal to the nerve anastomosis site at postoperative week 4. Another six rats were treated exactly in the same way in postoperative week 8. Six normal rats were used as controls. Intact facial nerve was observed after injection of CTb as well. Neurons of facial nuclei labeled positively by CTb were detected immunohistochemically, and the numbers were counted. CTb-positive neurons in the control group were 1311 +/- 258 (n = 6). CTb-positive neurons in the group (n = 6) with laser nerve welding were 1174 +/- 122 in postoperative week 4 and 1562 +/- 565 in postoperative week 8. CTb-positive neurons in the group (n = 6) with microsurgical suture were 1066 +/- 89 in postoperative week 4 and 1443 +/- 531 in postoperative week 8. CTb-positive neurons were seen significantly more in the group with laser welding than in the group with microsurgical suture in postoperative week (P = 0.028), but there was not much difference in postoperative week 8 (P = 0.463). None of 12 rats showed dehiscence at the nerve anastomosis done by laser welding. This study shows that nerve regeneration is more apparent in the nerve repaired by laser welding than in that repaired by microsurgical suture.

  12. Head exposure system for a human provocation study to assess the possible influence of UMTS-like electromagnetic fields on cerebral blood circulation using near-infrared imaging.

    PubMed

    Lehmann, Hugo; Pollara, Laurent; Spichtig, Sonja; Kühn, Sven; Wolf, Martin

    2012-02-01

    A head exposure setup for efficient and precisely defined exposure of human subjects equipped with a near-infrared imaging (NIRI) sensor is presented. In a partially shielded anechoic chamber the subjects were exposed to Universal Mobile Telecommunications System (UMTS)-like electromagnetic fields (EMF) by using a patch antenna at a distance of 4 cm from the head. The non-contact design of the exposure setup enabled NIRI sensors to easily attach to the head. Moreover, different regions of the head were chosen for localised exposure and simultaneous NIRI investigation. The control software enabled the simple adaptation of the test parameters during exploratory testing as well as the performance of controlled, randomised, crossover and double-blind provocation studies. Four different signals with a carrier frequency of 1900 MHz were chosen for the exposure: a simple continuous wave signal and three different UMTS signals. Furthermore, three exposure doses were available: sham, low (spatial peak specific absorption rate (SAR) = 0.18 W/kg averaged over 10 g) and high (spatial peak SAR = 1.8 W/kg averaged over 10 g). The SAR assessment was performed by measurement and simulation. Direct comparison of measurement and numerical results showed good agreement in terms of spatial peak SAR and SAR distribution. The variability analysis of the spatial peak SAR over 10 g was assessed by numerical simulations. Maximal deviations of -22% and +32% from the nominal situation were observed. Compared to other exposure setups, the present setup allows for low exposure uncertainty, combined with high SAR efficiency, easy access for the NIRI sensor and minimal impairment of test subjects.

  13. Cutting your nerve changes your brain.

    PubMed

    Taylor, Keri S; Anastakis, Dimitri J; Davis, Karen D

    2009-11-01

    Following upper limb peripheral nerve transection and surgical repair, some patients regain good sensorimotor function while others do not. Understanding peripheral and central mechanisms that contribute to recovery may facilitate the development of new therapeutic interventions. Plasticity following peripheral nerve transection has been demonstrated throughout the neuroaxis in animal models of nerve injury. However, the brain changes that occur following peripheral nerve transection and surgical repair in humans have not been examined. Furthermore, the extent to which peripheral nerve regeneration influences functional and structural brain changes has not been characterized. Therefore, we asked whether functional changes are accompanied by grey and/or white matter structural changes and whether these changes relate to sensory recovery? To address these key issues we (i) assessed peripheral nerve regeneration; (ii) measured functional magnetic resonance imaging brain activation (blood oxygen level dependent signal; BOLD) in response to a vibrotactile stimulus; (iii) examined grey and white matter structural brain plasticity; and (iv) correlated sensory recovery measures with grey matter changes in peripheral nerve transection and surgical repair patients. Compared to each patient's healthy contralesional nerve, transected nerves have impaired nerve conduction 1.5 years after transection and repair, conducting with decreased amplitude and increased latency. Compared to healthy controls, peripheral nerve transection and surgical repair patients had altered blood oxygen level dependent signal activity in the contralesional primary and secondary somatosensory cortices, and in a set of brain areas known as the 'task positive network'. In addition, grey matter reductions were identified in several brain areas, including the contralesional primary and secondary somatosensory cortices, in the same areas where blood oxygen level dependent signal reductions were identified

  14. MMP19 expression in the human optic nerve

    PubMed Central

    Chirco, Kathleen R.; Hazlewood, Ralph J.; Miller, Kathy; Workalemahu, Grefachew; Jampol, Lee M.; Lesser, G. Robert; Mullins, Robert F.; Kuehn, Markus H.; Fingert, John H.

    2016-01-01

    Purpose The defining feature of glaucoma is excavation of the optic nerve head; however, the mechanism of this loss of tissue is not well understood. We recently discovered a copy number variation upstream of matrix metalloproteinase 19 (MMP19) in a large, autosomal dominant pedigree with a congenital malformation of the optic disc called cavitary optic disc anomaly (CODA). Patients with CODA have abnormal optic discs that exhibit an excavated shape similar to cupping seen in glaucoma. The goal of this study is to characterize the localization of MMP19 within the human optic nerve. Methods The MMP19 protein in the optic nerve was evaluated with western blot analysis and with immunohistochemistry in sagittal and en face/cross sections of optic nerves obtained from healthy human donor eyes. Results The MMP19 protein was detected in the human optic nerve, retina, and RPE/choroid with western blot analysis, with highest expression in the retina and the optic nerve. Using immunohistochemistry, MMP19 was localized within the optic nerve to the extracellular space within the septa that separate bundles of optic nerve axons into fascicles. The presence of MMP19 within the optic nerve septa was further confirmed by the colocalization of MMP19 to this structure with type IV collagen. Strong labeling of MMP19 was also detected in the arachnoid layer of the optic nerve sheath. Finally, immunohistochemistry of the optic nerve cross sections demonstrated that MMP19 shows a peripheral to central gradient, with more abundant labeling along the edges of the optic nerve and in the arachnoid layer than in the center of the nerve. Conclusions Abundant MMP19 was detected in the optic nerve head, the primary site of pathology in patients with CODA. The localization of MMP19 to the optic nerve septa is consistent with its predicted secretion and accumulation within the extracellular spaces of this tissue. Moreover, the lateral localization of MMP19 observed in the optic nerve cross

  15. Head Tilt

    MedlinePlus

    ... Throat Emotional Problems Eyes Fever From Insects or Animals Genitals and Urinary Tract Glands & Growth Head Neck & Nervous System Heart Infections Learning Disabilities Obesity Orthopedic Prevention Sexually Transmitted Skin Tobacco ...

  16. Head Noises.

    ERIC Educational Resources Information Center

    Senior, Tom

    2000-01-01

    Explains how a toy called "Sound Bites" can be modified to demonstrate the transmission of sound waves. Students can hear music from the toy when they press it against any bone in their heads or shoulders. (WRM)

  17. Head Injuries

    MedlinePlus

    ... before. Often, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  18. Head lice

    MedlinePlus

    ... make the nits easier to remove. Some dishwashing detergents can help dissolve the "glue" that makes the ... clothes and bed linens in hot water with detergent. This also helps prevent head lice from spreading ...

  19. Head Injuries

    MedlinePlus

    ... won't stop crying complains of head and neck pain (younger or nonverbal children may be more fussy) ... vision pupils of unequal size weakness or paralysis neck pain or stiffness seizure If your child is unconscious: ...

  20. Modeling Heart Rate Regulation—Part I: Sit-to-stand Versus Head-up Tilt

    PubMed Central

    Olufsen, Mette S.; Alston, April V.; Tran, Hien T.; Ottesen, Johnny T.; Novak, Vera

    2008-01-01

    In this study we describe a model predicting heart rate regulation during postural change from sitting to standing and during head-up tilt in five healthy elderly adults. The model uses blood pressure as an input to predict baroreflex firing-rate, which in turn is used to predict efferent parasympathetic and sympathetic outflows. The model also includes the combined effects of vestibular and central command stimulation of muscle sympathetic nerve activity, which is increased at the onset of postural change. Concentrations of acetylcholine and noradrenaline, predicted as functions of sympathetic and parasympathetic outflow, are then used to estimate the heart rate response. Dynamics of the heart rate and the baroreflex firing rate are modeled using a system of coupled ordinary delay differential equations with 17 parameters. We have derived sensitivity equations and ranked sensitivities of all parameters with respect to all state variables in our model. Using this model we show that during head-up tilt, the baseline firing-rate is larger than during sit-to-stand and that the combined effect of vestibular and central command stimulation of muscle sympathetic nerve activity is less pronounced during head-up tilt than during sit-to-stand. PMID:18064571

  1. Blood-brain barrier permeability and nerve cell damage in rat brain 14 and 28 days after exposure to microwaves from GSM mobile phones.

    PubMed

    Eberhardt, Jacob L; Persson, Bertil R R; Brun, Arne E; Salford, Leif G; Malmgren, Lars O G

    2008-01-01

    We investigated the effects of global system for mobile communication (GSM) microwave exposure on the permeability of the blood-brain barrier and signs of neuronal damage in rats using a real GSM programmable mobile phone in the 900 MHz band. Ninety-six non-anaesthetized rats were either exposed to microwaves or sham exposed in TEM-cells for 2 h at specific absorption rates of average whole-body Specific Absorption Rates (SAR) of 0.12, 1.2, 12, or 120 mW/kg. The rats were sacrificed after a recovery time of either 14 or 28 d, following exposure and the extravazation of albumin, its uptake into neurons, and occurrence of damaged neurons was assessed. Albumin extravazation and also its uptake into neurons was seen to be enhanced after 14 d (Kruskal Wallis test: p = 0.02 and 0.002, respectively), but not after a 28 d recovery period. The occurrence of dark neurons in the rat brains, on the other hand, was enhanced later, after 28 d (p = 0.02). Furthermore, in the 28-d brain samples, neuronal albumin uptake was significantly correlated to occurrence of damaged neurons (Spearman r = 0.41; p < 0.01).

  2. Sword-Like Trauma to the Shoulder with Open Head-Splitting Fracture of the Head

    PubMed Central

    Pantazis, Konstantinos; Iliopoulos, Ilias; Seferlis, Ioannis; Kokkalis, Zinon

    2016-01-01

    Head-splitting fractures occur as a result of violent compression of the head against the glenoid; the head splits and the tuberosities may remain attached to the fragments or split and separate. Isolated humeral head-splitting fractures are rare injuries. Favorable results with osteosynthesis can be difficult to achieve because of the very proximal location of the head fracture and associated poor vascularity. We present a case of a 67-year-old man who sustained a severe, sword-like trauma to his left shoulder after a road traffic accident with associated isolated open Gustilo-Anderson IIIA humeral head-splitting fracture. Bony union was achieved with minimal internal fixation but the clinical outcome deteriorated due to accompanying axillary nerve apraxia. To our knowledge, this type of sword-like injury with associated humeral head-split fracture has not previously been reported. PMID:27478665

  3. Abducens Nerve Palsy in Pregnancy: A Case Report

    PubMed Central

    Yousefi, Sayedeh Reyhaneh

    2016-01-01

    Headache, blurring of vision and confusion are neurologic symptoms of preeclampsia. Whereas abducens nerve palsy during pregnancy is an extremely rare condition, we report here a 40-year-old patient with diplopia, blurring of vision and abducens nerve palsy in the 39th week of pregnancy with history of hypertension (HTN). No specific pathology was found. Symptoms of abducens nerve palsy were resolved spontaneously by controlling blood pressure after delivery. PMID:28208948

  4. Nerve Injuries in Athletes.

    ERIC Educational Resources Information Center

    Collins, Kathryn; And Others

    1988-01-01

    Over a two-year period this study evaluated the condition of 65 athletes with nerve injuries. These injuries represent the spectrum of nerve injuries likely to be encountered in sports medicine clinics. (Author/MT)

  5. Electromechanical Nerve Stimulator

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Supplee, Frank H., Jr.; Prass, Richard L.

    1993-01-01

    Nerve stimulator applies and/or measures precisely controlled force and/or displacement to nerve so response of nerve measured. Consists of three major components connected in tandem: miniature probe with spherical tip; transducer; and actuator. Probe applies force to nerve, transducer measures force and sends feedback signal to control circuitry, and actuator positions force transducer and probe. Separate box houses control circuits and panel. Operator uses panel to select operating mode and parameters. Stimulator used in research to characterize behavior of nerve under various conditions of temperature, anesthesia, ventilation, and prior damage to nerve. Also used clinically to assess damage to nerve from disease or accident and to monitor response of nerve during surgery.

  6. Update and critical appraisal of combined timolol and carbonic anhydrase inhibitors and the effect on ocular blood flow in glaucoma patients.

    PubMed

    Moss, Adam M; Harris, Alon; Siesky, Brent; Rusia, Deepam; Williamson, Kathleen M; Shoshani, Yochai

    2010-04-26

    Topical hypotensive therapy with both timolol and carbonic anhydrase inhibitors has been shown to be efficacious at reducing intraocular pressure. Many prospective studies have also suggested that carbonic anhydrase inhibitors augment ocular blood flow and vascular regulation independent of their hypotensive effects. Although consistent in their findings, these studies must be cautiously interpreted due to the limitations of study design and specific blood flow imaging modalities. The purpose of this review is to appraise and critically evaluate the current body of literature investigating the effects of combined treatment with topical carbonic anhydrase inhibitors and timolol in patients with glaucoma with respect to ocular blood flow, visual function, and optic nerve head structure.

  7. Effect of 1% Inspired CO2 During Head-Down Tilt on Ocular Structures, Cerebral Blood Flow, and Visual Acuity in Healthy Human Subjects

    NASA Technical Reports Server (NTRS)

    Laurie, S. S.; Hu, X.; Lee, S. M. C.; Martin, D. S.; Phillips, T. R.; Ploutz-Snyder, R.; Smith, S. M.; Stenger, M. B.; Taibbi, G.; Zwart, S. R.; Vizzeri, G.

    2016-01-01

    The cephalad fluid shift induced by microgravity has been hypothesized to elevate intracranial pressure (ICP) and contribute to the development of the visual impairment/intracranial pressure (VIIP) syndrome experienced by many astronauts during and after long-duration space flight. In addition, elevated ambient partial pressure of carbon dioxide (PCO2) on the International Space Station (ISS) has also been hypothesized to contribute to the development of VIIP. We seek to determine if an acute, mild CO2 exposure, similar to that occurring on the ISS, combined with the cephalad fluid shift induced by head-down tilt will induce ophthalmic and ICP changes consistent with the VIIP syndrome.

  8. Optic Nerve Pit

    MedlinePlus

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

  9. What are Head Cavities? - A History of Studies on Vertebrate Head Segmentation.

    PubMed

    Kuratani, Shigeru; Adachi, Noritaka

    2016-06-01

    Motivated by the discovery of segmental epithelial coeloms, or "head cavities," in elasmobranch embryos toward the end of the 19th century, the debate over the presence of mesodermal segments in the vertebrate head became a central problem in comparative embryology. The classical segmental view assumed only one type of metamerism in the vertebrate head, in which each metamere was thought to contain one head somite and one pharyngeal arch, innervated by a set of cranial nerves serially homologous to dorsal and ventral roots of spinal nerves. The non-segmental view, on the other hand, rejected the somite-like properties of head cavities. A series of small mesodermal cysts in early Torpedo embryos, which were thought to represent true somite homologs, provided a third possible view on the nature of the vertebrate head. Recent molecular developmental data have shed new light on the vertebrate head problem, explaining that head mesoderm evolved, not by the modification of rostral somites of an amphioxus-like ancestor, but through the polarization of unspecified paraxial mesoderm into head mesoderm anteriorly and trunk somites posteriorly.

  10. Re-innervation of facial nerve territory using a composite hypoglossal nerve--muscle autograft--facial nerve bridge. An experimental model in sheep.

    PubMed

    Drew, S J; Fullarton, A C; Glasby, M A; Mountain, R E; Murray, J A

    1995-04-01

    The hypoglossal nerve has been used both entirely and in part to repair the facial nerve. Using the partial technique it may be difficult to obtain sufficient length and a free interposed graft is then required to extend the hypoglossal element. In six sheep the facial nerve was excised between its emergence from the stylomastoid foramen and its bifurcation in the parotid gland. The hypoglossal nerve was exposed and split longitudinally producing a limb which was reflected towards the distal stump of the facial nerve. This left a gap of 4-5 cm which was bridged with a freeze-thawed coaxially aligned skeletal muscle autograft. The sheep were examined at 8 months. Laser doppler blood-flow studies showed the blood-flow distal to the graft to be about 25% of that at an equivalent site on the normal side. Peak nerve conduction velocities were also reduced on the repaired side but stimulation of the proximal hypoglossal nerve was nevertheless capable of causing adequate contraction of both facial and tongue muscles. Histological comparison of the repaired facial nerves with equivalent sites on the normal side showed a reduction in mean axon and fibre diameters with normal myelin sheath thickness for the regenerated axon sizes. All of these features are to be expected in a regenerated nerve and are consistent with a good level of recovery of function.

  11. Optic Nerve Elongation

    PubMed Central

    Alvi, Aijaz; Janecka, Ivo P.; Kapadia, Silloo; Johnson, Bruce L.; McVay, William

    1996-01-01

    The length of the optic nerves is a reflection of normal postnatal cranio-orbital development. Unilateral elongation of an optic nerve has been observed in two patients with orbital and skull base neoplasms. In the first case as compared to the patient's opposite, normal optic nerve, an elongated length of the involved optic nerve of 45 mm was present. The involved optic nerve in the second patient was 10 mm longer than the normal opposite optic nerve. The visual and extraocular function was preserved in the second patient. The first patient had only light perception in the affected eye. In this paper, the embryology, anatomy, and physiology of the optic nerve and its mechanisms of stretch and repair are discussed. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 13 PMID:17170975

  12. Assessment of nerve morphology in nerve activation during electrical stimulation

    NASA Astrophysics Data System (ADS)

    Gomez-Tames, Jose; Yu, Wenwei

    2013-10-01

    The distance between nerve and stimulation electrode is fundamental for nerve activation in Transcutaneous Electrical Stimulation (TES). However, it is not clear the need to have an approximate representation of the morphology of peripheral nerves in simulation models and its influence in the nerve activation. In this work, depth and curvature of a nerve are investigated around the middle thigh. As preliminary result, the curvature of the nerve helps to reduce the simulation amplitude necessary for nerve activation from far field stimulation.

  13. Magnetic Heads

    NASA Astrophysics Data System (ADS)

    Yokoshima, Tokihiko

    Figure 6.1 shows how rapidly the areal density of hard disk drives (HDD) has been increasing over the past 20 years [1]. Several critical innovations were necessary to bring about such rapid progress in the field of magnetic recording [2]. One of the most significant innovations from the viewpoint of material improvement was the electrodeposition of permalloy (Ni80Fe20), which was introduced by IBM in 1979 as the core material of a thin-film inductive head to increase the magnetic recording density [3]. After the introduction of the magneto-resistive (MR) element as the read head and the electrodeposited permalloy as the write head by IBM in 1991 [4], the rate of increase in the recording density of HDDs jumped from 30% per year to 60% per year. Recently, a giant magneto-resistive (GMR) element has been used for the read element instead of the MR element. The rate of increase in the recording density jumped to over 100% per year in 1999, which is an incredible rate of increase. Since 2002, however, the rate of increase has decreased to 30%; thus, new innovations are required to maintain the rate of increase. In 2004, the practical use of perpendicular magnetic recording instead of longitudinal magnetic recording was announced [5]. This system is a critical innovation for developing high-performance HDD systems with high-recording density. The design of the magnetic recording head was changed because of the change of the recording system.

  14. Angioleiomyomas in the head and neck: A retrospective clinical and immunohistochemical analysis

    PubMed Central

    LIU, YING; LI, BO; LI, LONGJIANG; LIU, YANBIN; WANG, CHENXING; ZHA, LAGABAIYILA

    2014-01-01

    Angioleiomyoma is a benign soft-tissue tumor originating from vascular smooth muscle, and is rare in the head and neck. The present study retrospectively examined a cohort of patients with head and neck angioleiomyoma treated at the West China Hospital of Stomatology, and also subjected archived tissues to modern immunohistochemical analysis. In total, 21 patients were treated for angioleiomyoma between 1978 and 2012 at the West China Hospital of Stomatology, Sichuan University (Chengdu, Sichuan, China). Medical records were examined and paraffin block sections were cut and stained with hematoxylin and eosin, Masson’s trichrome stain and Van Gieson stain, prior to being subjected to immunohistochemical analysis to re-evaluate and confirm the diagnoses. Angioleiomyomas were found to account for only 0.18% of the benign head and neck tumors in the patients presenting to the hospital over the past 34 years. The diagnosis was more common in males (male:female ratio, 1.625:1) and the mean age at diagnosis was 42.5 years. The most common sites were the buccal mucosa, parotid gland and palate. More than half of the tumors (61.9%) were >2 cm in diameter. Five tumors presented with pain and/or tenderness. The histological subtype was reported as solid in five cases, venous in six, cavernous in nine and venous-cavernous in one. Three tumors exhibited nerve neurofibrils. All tumors were excised with no subsequent recurrence. Cytological and imaging examinations were not useful for pre-operative diagnosis. Angioleiomyoma is a benign tumor that causes limited morbidity. Surgical excision is the only effective treatment and recurrence is rare. The present study revealed that nerves were present in a small proportion (14.3%) of tumors. It was hypothesized that the compression of nerves accompanying numerous blood vessels in the tumor may cause pain, particularly in venous- and cavernous-type angioleiomyomas. PMID:24959254

  15. Effects of intranasal cocaine on sympathetic nerve discharge in humans.

    PubMed Central

    Jacobsen, T N; Grayburn, P A; Snyder, R W; Hansen, J; Chavoshan, B; Landau, C; Lange, R A; Hillis, L D; Victor, R G

    1997-01-01

    Cocaine-induced cardiovascular emergencies are mediated by excessive adrenergic stimulation. Animal studies suggest that cocaine not only blocks norepinephrine reuptake peripherally but also inhibits the baroreceptors, thereby reflexively increasing sympathetic nerve discharge. However, the effect of cocaine on sympathetic nerve discharge in humans is unknown. In 12 healthy volunteers, we recorded blood pressure and sympathetic nerve discharge to the skeletal muscle vasculature using intraneural microelectrodes (peroneal nerve) during intranasal cocaine (2 mg/kg, n = 8) or lidocaine (2%, n = 4), an internal local anesthetic control, or intravenous phenylephrine (0.5-2.0 microg/kg, n = 4), an internal sympathomimetic control. Experiments were repeated while minimizing the cocaine-induced rise in blood pressure with intravenous nitroprusside to negate sinoaortic baroreceptor stimulation. After lidocaine, blood pressure and sympathetic nerve discharge were unchanged. After cocaine, blood pressure increased abruptly and remained elevated for 60 min while sympathetic nerve discharge initially was unchanged and then decreased progressively over 60 min to a nadir that was only 2+/-1% of baseline (P < 0.05); however, plasma venous norepinephrine concentrations (n = 5) were unchanged up to 60 min after cocaine. Sympathetic nerve discharge fell more rapidly but to the same nadir when blood pressure was increased similarly with phenylephrine. When the cocaine-induced increase in blood pressure was minimized (nitroprusside), sympathetic nerve discharge did not decrease but rather increased by 2.9 times over baseline (P < 0.05). Baroreflex gain was comparable before and after cocaine. We conclude that in conscious humans the primary effect of intranasal cocaine is to increase sympathetic nerve discharge to the skeletal muscle bed. Furthermore, sinoaortic baroreflexes play a pivotal role in modulating the cocaine-induced sympathetic excitation. The interplay between these

  16. Endocrine tumors associated with the vagus nerve.

    PubMed

    Varoquaux, Arthur; Kebebew, Electron; Sebag, Fréderic; Wolf, Katherine; Henry, Jean-François; Pacak, Karel; Taïeb, David

    2016-09-01

    The vagus nerve (cranial nerve X) is the main nerve of the parasympathetic division of the autonomic nervous system. Vagal paragangliomas (VPGLs) are a prime example of an endocrine tumor associated with the vagus nerve. This rare, neural crest tumor constitutes the second most common site of hereditary head and neck paragangliomas (HNPGLs), most often in relation to mutations in the succinate dehydrogenase complex subunit D (SDHD) gene. The treatment paradigm for VPGL has progressively shifted from surgery to abstention or therapeutic radiation with curative-like outcomes. Parathyroid tissue and parathyroid adenoma can also be found in close association with the vagus nerve in intra or paravagal situations. Vagal parathyroid adenoma can be identified with preoperative imaging or suspected intraoperatively by experienced surgeons. Vagal parathyroid adenomas located in the neck or superior mediastinum can be removed via initial cervicotomy, while those located in the aortopulmonary window require a thoracic approach. This review particularly emphasizes the embryology, molecular genetics, and modern imaging of these tumors.

  17. Structure-Activity Relationship of Nerve-Highlighting Fluorophores

    PubMed Central

    Gibbs, Summer L.; Xie, Yang; Goodwill, Haley L.; Nasr, Khaled A.; Ashitate, Yoshitomo; Madigan, Victoria J.; Siclovan, Tiberiu M.; Zavodszky, Maria; Tan Hehir, Cristina A.; Frangioni, John V.

    2013-01-01

    Nerve damage is a major morbidity associated with numerous surgical interventions. Yet, nerve visualization continues to challenge even the most experienced surgeons. A nerve-specific fluorescent contrast agent, especially one with near-infrared (NIR) absorption and emission, would be of immediate benefit to patients and surgeons. Currently, there are only three classes of small molecule organic fluorophores that penetrate the blood nerve barrier and bind to nerve tissue when administered systemically. Of these three classes, the distyrylbenzenes (DSBs) are particularly attractive for further study. Although not presently in the NIR range, DSB fluorophores highlight all nerve tissue in mice, rats, and pigs after intravenous administration. The purpose of the current study was to define the pharmacophore responsible for nerve-specific uptake and retention, which would enable future molecules to be optimized for NIR optical properties. Structural analogs of the DSB class of small molecules were synthesized using combinatorial solid phase synthesis and commercially available building blocks, which yielded more than 200 unique DSB fluorophores. The nerve-specific properties of all DSB analogs were quantified using an ex vivo nerve-specific fluorescence assay on pig and human sciatic nerve. Results were used to perform quantitative structure-activity relationship (QSAR) modeling and to define the nerve-specific pharmacophore. All DSB analogs with positive ex vivo fluorescence were tested for in vivo nerve specificity in mice to assess the effect of biodistribution and clearance on nerve fluorescence signal. Two new DSB fluorophores with the highest nerve to muscle ratio were tested in pigs to confirm scalability. PMID:24039960

  18. Low-order chaos in sympathetic nerve activity and scaling of heartbeat intervals

    NASA Astrophysics Data System (ADS)

    Osaka, Motohisa; Kumagai, Hiroo; Sakata, Katsufumi; Onami, Toshiko; Chon, Ki H.; Watanabe, Mari A.; Saruta, Takao

    2003-04-01

    The mechanism of 1/f scaling of heartbeat intervals remains unknown. We recorded heartbeat intervals, sympathetic nerve activity, and blood pressure in conscious rats with normal or high blood pressure. Using nonlinear analyses, we demonstrate that the dynamics of this system of three variables is low-order chaos, and that sympathetic nerve activity leads to heartbeat interval and blood pressure changes. It is suggested that impaired regulation of blood pressure by sympathetic nerve activity is likely to cause experimentally observable steeper scaling of heartbeat intervals in hypertensive (high blood pressure) rats.

  19. Low-order chaos in sympathetic nerve activity causes 1/f fluctuation of heartbeat intervals

    NASA Astrophysics Data System (ADS)

    Osaka, Motohisa; Kumagai, Hiroo; Sakata, Katsufumi; Onami, Toshiko; Chon, Ki H.; Watanabe, Mari A.; Saruta, Takao

    2004-04-01

    The mechanism of 1/f scaling of heartbeat intervals remains unknown. We recorded heartbeat intervals, sympathetic nerve activity, and blood pressure in conscious rats with normal or high blood pressure. Using nonlinear analyses, we demonstrate that the dynamics of this system of 3 variables is low-order chaos, and that sympathetic nerve activity leads to heartbeat interval and blood pressure changes. It is suggested that 1/f scaling of heartbeat intervals results from the low-order chaos of these variables and that impaired regulation of blood pressure by sympathetic nerve activity is likely to cause experimentally observable steeper scaling of heartbeat intervals in hypertensive (high blood pressure) rats.

  20. Vestibular activation of sympathetic nerve activity

    NASA Technical Reports Server (NTRS)

    Ray, C. A.; Carter, J. R.

    2003-01-01

    AIM: The vestibulosympathetic reflex refers to sympathetic nerve activation by the vestibular system. Animal studies indicate that the vestibular system assists in blood pressure regulation during orthostasis. Although human studies clearly demonstrate activation of muscle sympathetic nerve activity (MSNA) during engagement of the otolith organs, the role of the vestibulosympathetic reflex in maintaining blood pressure during orthostasis is not well-established. Examination of the vestibulosympathetic reflex with other cardiovascular reflexes indicates that it is a powerful and independent reflex. Ageing, which is associated with an increased risk for orthostatic hypotension, attenuates the vestibulosympathetic reflex. The attenuated reflex is associated with a reduction in arterial pressure. CONCLUSION: These findings suggest that the vestibulosympathetic reflex assists in blood pressure regulation in humans, but future studies examining this reflex in other orthostatically intolerant populations are necessary to address this hypothesis.

  1. The nerve: A fragile balance between physiology and pathophysiology.

    PubMed

    Estebe, Jean-Pierre; Atchabahian, Arthur

    2017-03-01

    Regarding nerves as simple cables and electrical conduits is a gross error that does not allow us to understand the anomalies and disorders observed postoperatively. Instead, nerves should be seen as a living tissue of which physiological regulation is as complex as that of the blood-brain barrier. This review describes the basic structure and functions of this blood-nerve barrier and highlights the mechanisms of its breakdown and the resultant disorders. For clinical practice, it is important to note that the diffusion of molecules from the perineurium or from the blood is very limited, and so the blood-nerve barrier is a major pharmacologic barrier. Any stress upon neural physiological balance, particularly the terminal vascular blood supply, will induce the classic inflammatory cascade. Due to the complexity of the vascular system, nerve ischaemia will occur more quickly when the terminal blood supply is compromised. This blood supply can adapt in a variety of ways but when these possibilities of adaptation are exceeded, tissue ischaemia may be more extensive. Also, even after the initial injury has subsided, inflammation can cause a secondary insult. This could be particularly important in some patients with subclinical neuropathy.

  2. Early applications of granulocyte colony-stimulating factor (G-CSF) can stabilize the blood-optic-nerve barrier and ameliorate inflammation in a rat model of anterior ischemic optic neuropathy (rAION).

    PubMed

    Wen, Yao-Tseng; Huang, Tzu-Lun; Huang, Sung-Ping; Chang, Chung-Hsing; Tsai, Rong-Kung

    2016-10-01

    Granulocyte colony-stimulating factor (G-CSF) was reported to have a neuroprotective effect in a rat model of anterior ischemic optic neuropathy (rAION model). However, the therapeutic window and anti-inflammatory effects of G-CSF in a rAION model have yet to be elucidated. Thus, this study aimed to determine the therapeutic window of G-CSF and investigate the mechanisms of G-CSF via regulation of optic nerve (ON) inflammation in a rAION model. Rats were treated with G-CSF on day 0, 1, 2 or 7 post-rAION induction for 5 consecutive days, and a control group were treated with phosphate-buffered saline (PBS). Visual function was assessed by flash visual evoked potentials at 4 weeks post-rAION induction. The survival rate and apoptosis of retinal ganglion cells were determined by FluoroGold labeling and TUNEL assay, respectively. ON inflammation was evaluated by staining of ED1 and Iba1, and ON vascular permeability was determined by Evans Blue extravasation. The type of macrophage polarization was evaluated using quantitative real-time PCR (qRT-PCR). The protein levels of TNF-α and IL-1β were analyzed by western blotting. A therapeutic window during which G-CSF could rescue visual function and retinal ganglion cell survival was demonstrated at day 0 and day 1 post-infarct. Macrophage infiltration was reduced by 3.1- and 1.6-fold by G-CSF treatment starting on day 0 and 1 post-rAION induction, respectively, compared with the PBS-treated group (P<0.05). This was compatible with 3.3- and 1.7-fold reductions in ON vascular permeability after G-CSF treatment compared with PBS treatment (P<0.05). Microglial activation was increased by 3.8- and 3.2-fold in the early (beginning treatment at day 0 or 1) G-CSF-treated group compared with the PBS-treated group (P<0.05). Immediate (within 30 mins of infarct) treatment with G-CSF also induced M2 microglia/macrophage activation. The cytokine levels were lower in the group that received immediate G-CSF treatment compared to

  3. Effects of mild (33 degrees C) and moderate (29 degrees C) hypothermia on cerebral blood flow and metabolism, lactate, and extracellular glutamate in experimental head injury.

    PubMed

    Mori, K; Maeda, M; Miyazaki, M; Iwase, H

    1998-12-01

    The effects of mild (33 degrees C) and moderate (29 degrees C) hypothermia were investigated to determine which temperature was more effective against compression-induced cerebral ischemia. Eighteen cats were anesthetized. The animals were divided into three groups according to deep-brain temperature (control, 37 degrees C; mild hypothermia, 33 degrees C; and moderate hypothermia, 29 degrees C). Intracranial pressure (ICP) and cerebral blood flow (CBF) were monitored, the latter by hydrogen clearance. Arteriovenous oxygen difference (AVDO2) and cerebral venous oxygen saturation (ScvO2) were measured in blood samples from the superior sagittal sinus. The cerebral metabolic rate of oxygen (CMRO2) and the cerebral metabolic rate of lactate (CMR lactate) were calculated. Extracellular glutamate was measured by microdialysis. ICP was increased by inflation of an epidural balloon until CBF became zero, and this ischemia was maintained for 5 min, after which the balloon was quickly deflated. All parameters were recorded over 6 h. Evans blue was injected to examine vascular permeability changes. CBF was decreased by 56% by mild hypothermia and by 77% by moderate hypothermia. Mild hypothermia had a coupled metabolic suppression whereas moderate hypothermia significantly increased AVDO2 and decreased ScvO2, producing a low CBF/CMRO2 (relative ischemia). After balloon deflation, all three groups showed reactive hyperemia, which was significantly reduced by mild and moderate hypothermia. CBF then decreased to 50% of pre-inflation values and ScvO2 decreased (post-ischemic hypoperfusion). CBF/CMRO2, ScvO2, and AVDO2 did not differ significantly between the three groups. After balloon deflation, all three groups showed increased CMR lactate, which was significantly reduced by mild and moderate hypothermia. Extracellular glutamate increased in control animals (3.8 +/- 1.72 microM), an effect most effectively suppressed in the mild hypothermia group (1.0 +/- 0.46 microM). Damaged

  4. Laryngeal nerve damage

    MedlinePlus

    ... Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery . 6th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap ... and Reconstructive Surgery, Department of Otolaryngology – Head and Neck Surgery, The University of Texas Medical School at Houston, ...

  5. Myocardial blood flow measurement with a conventional dual-head SPECT/CT with spatiotemporal iterative reconstructions - a clinical feasibility study

    PubMed Central

    Alhassen, Fares; Nguyen, Nhan; Bains, Sukhkarn; Gould, Robert G; Seo, Youngho; Bacharach, Stephen L; Song, Xiyun; Shao, Lingxiong; Gullberg, Grant T; Aparici, Carina Mari

    2014-01-01

    Cardiac single photon emission computed tomography (SPECT) cameras typically rotate too slowly around a patient to capture changes in the blood pool activity distribution and provide accurate kinetic parameters. A spatiotemporal iterative reconstruction method to overcome these limitations was investigated. Dynamic rest/stress 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) SPECT/CT was performed along with reference standard rest/stress dynamic positron emission tomography (PET/CT) 13N-NH3 in five patients. The SPECT data were reconstructed using conventional and spatiotemporal iterative reconstruction methods. The spatiotemporal reconstruction yielded improved image quality, defined here as a statistically significant (p<0.01) 50% contrast enhancement. We did not observe a statistically significant difference between the correlations of the conventional and spatiotemporal SPECT myocardial uptake K 1 values with PET K 1 values (r=0.25, 0.88, respectively) (p<0.17). These results indicate the clinical feasibility of quantitative, dynamic SPECT/CT using 99mTc-MIBI and warrant further investigation. Spatiotemporal reconstruction clearly provides an advantage over a conventional reconstruction in computing K 1. PMID:24380045

  6. Peripheral nerve surgery.

    PubMed

    McQuarrie, I G

    1985-05-01

    In treating the three main surgical problems of peripheral nerves--nerve sheath tumors, entrapment neuropathies, and acute nerve injuries--the overriding consideration is the preservation and restoration of neurologic function. Because of this, certain other principles may need to be compromised. These include achieving a gross total excision of benign tumors, employing conservative therapy as long as a disease process is not clearly progressing, and delaying repair of a nerve transection until the skin wound has healed. Only three pathophysiologic processes need be considered: neurapraxia (focal segmental dymyelination), axonotmesis (wallerian degeneration caused by a lesion that does not disrupt fascicles of nerve fibers), and neurotmesis (wallerian degeneration caused by a lesion that interrupts fascicles). With nerve sheath tumors and entrapment neuropathies, the goal is minimize the extent to which neurapraxia progresses to axonotmesis. The compressive force is relieved without carrying out internal neurolysis, a procedure that is poorly tolerated, presumably because a degree of nerve ischemia exists with any long-standing compression. When the nerve has sustained blunt trauma (through acute compression, percussion, or traction), the result can be a total loss of function and an extensive neuroma-in-continuity (scarring within the nerve). However, the neural pathophysiology may amount to nothing more than axonotmesis. Although this lesion, in time, leads to full and spontaneous recovery, it must be differentiated from the neuroma-in-continuity that contains disrupted fascicles requiring surgery. Finally, with open nerve transection, the priority is to match the fascicles of the proximal stump with those of the distal stump, a goal that is best achieved if primary neurorrhaphy is carried out.

  7. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    PubMed

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure.

  8. Head lice

    PubMed Central

    2011-01-01

    Introduction Head lice can only be diagnosed by finding live lice, as eggs take 7 days to hatch and may appear viable for weeks after death of the egg. Infestation may be more likely in school children, with risks increased in children with more siblings, longer hair, and of lower socioeconomic group. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for head lice? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 26 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: benzyl alcohol, dimeticone, herbal and essential oils, insecticide combinations, isopropyl myristate, ivermectin, lindane, malathion, mechanical removal by combing ("bug busting"), oral trimethoprim–sulfamethoxazole (co-trimoxazole, TMP-SMX), permethrin, phenothrin, pyrethrum, and spinosad. PMID:21575285

  9. Head lice

    PubMed Central

    2015-01-01

    Introduction Head louse infection is diagnosed by finding live lice, as eggs take 7 days to hatch (but a few may take longer, up to 13 days) and may appear viable for weeks after death of the egg. Infestation may be more likely in school children, with risks increased in children with more siblings or of lower socioeconomic group. Factors such as longer hair make diagnosis and treatment more difficult. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of physically acting treatments for head lice? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found six studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: 1,2-octanediol, dimeticone, herbal and essential oils, and isopropyl myristate. PMID:25587918

  10. Effects of lead acetate on guinea pig - cochear microphonics, action potential, and motor nerve conduction velocity

    SciTech Connect

    Yamamura, K.; Maehara, N.; Terayama, K.; Ueno, N.; Kohyama, A.; Sawada, Y.; Kishi, R.

    1987-04-01

    Segmental demyelination and axonal degeneration of motor nerves induced by lead exposure is well known in man, and animals. The effect of lead acetate exposure to man may involve the cranial nerves, since vertigo and sensory neuronal deafness have been reported among lead workers. However, there are few reports concerning the dose-effects of lead acetate both to the peripheral nerve and the cranial VII nerve with measurement of blood lead concentration. The authors investigated the effects of lead acetate to the cochlea and the VIII nerve using CM (cochlear microphonics) and AP (action potential) of the guinea pigs. The effects of lead acetate to the sciatic nerve were measured by MCV of the sciatic nerve with measurement of blood lead concentration.

  11. Pathophysiology of nerve regeneration and nerve reconstruction in burned patients.

    PubMed

    Coert, J Henk

    2010-08-01

    In extensive burns peripheral nerves can be involved. The injury to the nerve can be direct by thermal or electrical burns, but nerves can also be indirectly affected by the systemic reaction that follows the burn. Mediators will be released causing a neuropathy to nerves remote from the involved area. Involved mediators and possible therapeutic options will be discussed. In burned patients nerves can be reconstructed using autologous nerve grafts or nerve conduits. A key factor is an adequate wound debridement and a well-vascularized bed to optimize the outgrowth of the axons. Early free tissue transfers have shown promising results.

  12. Glossopharyngeal Nerve Schwannoma

    PubMed Central

    Puzzilli, F.; Mastronardi, L.; Agrillo, U.; Nardi, P.

    1999-01-01

    Complete resection with conservation of cranial nerves is the primary goal of contemporary surgery for lower cranial nerve tumors. We describe the case of a patient with a schwannoma of the left glossopharyngeal nerve, operated on in our Neurosurgical Unit. The far lateral approach combined with laminectomy of the posterior arch of C1 was done in two steps. The procedure allowed total tumor resection and was found to be better than classic unilateral suboccipital or combined supra- and infratentorial approaches. The advantages and disadvantages of the far lateral transcondylar approach, compared to the other more common approaches, are discussed. ImagesFigure 1Figure 2 PMID:17171083

  13. Effects of ozone on sciatic nerve in rat.

    PubMed

    Lin, Q; Chen, H; Lu, C; Wang, B; Zhang, Y; He, X; Yu, B

    2011-09-01

    This study evaluated the influence of ozone on rat sciatic nerve structure and function. Thirty Wistar rats were randomly divided into six groups (n = 5). In groups I to IV, 1ml of ozone (O(3)) 10 μg/ml, 30 μg/ml, 50 μg/ml, 8 0 μg/ml was injected at the junction of gluteus maximus margin and lateral edge of the long head of biceps femoris respectively, in group V, 1 ml of pure O(2) was injected at the same point, and group V had puncture without any injection. Ozone was manufactured by an ozone generator (Ozone Line Co, Italy). The rats were investigated by both gross measurement and behavioral changes. One day, one week and three weeks after injection, rat hindlimb footprints were measured and the sciatic nerve function index (SFI) was calculated, and after three weeks, all right sciatic nerves were exposed under anesthesia. Near neural stimulation of the rat sciatic nerve was calculated and nerve conduction velocity, latency and maximum amplitude recorded. Animals were sacrificed for pathology, and ipsilateral triceps surae were taken for wet weight. No serious behavioral abnormalities were observed in any animal. SFI comparison in the various times and various groups showed no significant differences (p<0.05), and nerve conduction velocity, latency and maximum amplitude difference amongst the groups was not significant (p<0.05). There were no abnormalities in peripheral nerves pathologically after injection. Our initial study suggests that ozone concentrations from 10 μg/ml to 80 μg/ml injected around rat's peripheral nerve will not cause serious sequelae or serious damage to the structure and function of peripheral nerve. This finding provides evidence of the safety of ozone injected around the peripheral nerve.

  14. Degenerative Nerve Diseases

    MedlinePlus

    Degenerative nerve diseases affect many of your body's activities, such as balance, movement, talking, breathing, and heart function. Many of these diseases are genetic. Sometimes the cause is a medical ...

  15. Optic Nerve Imaging

    MedlinePlus

    ... machines can help monitor and detect loss of optic nerve fibers. The Heidelberg Retina Tomograph (HRT) is a special ... keeping organized, you can establish a routine that works for you. Read more » Are You at Risk ...

  16. Axillary nerve dysfunction

    MedlinePlus

    ... Causes Axillary nerve dysfunction is a form of peripheral neuropathy . It occurs when there is damage to the ... Multiple mononeuropathy Muscle function loss Numbness and tingling Peripheral neuropathy Systemic Review Date 2/3/2015 Updated by: ...

  17. Tibial nerve dysfunction

    MedlinePlus

    ... Tibial nerve dysfunction is an unusual form of peripheral neuropathy . It occurs when there is damage to the ... PA: Elsevier Saunders; 2012:chap 76. Shy ME. Peripheral neuropathies. In: Goldman L, Schafer AI, eds. Goldman-Cecil ...

  18. Vagus Nerve Stimulation.

    PubMed

    Howland, Robert H

    2014-06-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality.

  19. Ulnar nerve damage (image)

    MedlinePlus

    ... is commonly injured at the elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where it crosses the elbow, so prolonged pressure on the elbow or entrapment ...

  20. Optic Nerve Disorders

    MedlinePlus

    ... of optic nerve disorders, including: Glaucoma is a group of diseases that are the leading cause of blindness in the United States. Glaucoma usually happens when the fluid pressure inside the eyes slowly rises and damages the ...

  1. Nerve Damage (Diabetic Neuropathies)

    MedlinePlus

    ... may include numbness or insensitivity to pain or temperature a tingling, burning, or prickling sensation sharp pains ... from working properly, the body cannot regulate its temperature as it should. Nerve damage can also cause ...

  2. Vagus Nerve Stimulation

    PubMed Central

    Howland, Robert H.

    2014-01-01

    The vagus nerve is a major component of the autonomic nervous system, has an important role in the regulation of metabolic homeostasis, and plays a key role in the neuroendocrine-immune axis to maintain homeostasis through its afferent and efferent pathways. Vagus nerve stimulation (VNS) refers to any technique that stimulates the vagus nerve, including manual or electrical stimulation. Left cervical VNS is an approved therapy for refractory epilepsy and for treatment resistant depression. Right cervical VNS is effective for treating heart failure in preclinical studies and a phase II clinical trial. The effectiveness of various forms of non-invasive transcutaneous VNS for epilepsy, depression, primary headaches, and other conditions has not been investigated beyond small pilot studies. The relationship between depression, inflammation, metabolic syndrome, and heart disease might be mediated by the vagus nerve. VNS deserves further study for its potentially favorable effects on cardiovascular, cerebrovascular, metabolic, and other physiological biomarkers associated with depression morbidity and mortality. PMID:24834378

  3. Diabetic Nerve Problems

    MedlinePlus

    ... at the wrong times. This damage is called diabetic neuropathy. Over half of people with diabetes get it. ... you change positions quickly Your doctor will diagnose diabetic neuropathy with a physical exam and nerve tests. Controlling ...

  4. Nerves and Tissue Repair.

    DTIC Science & Technology

    1992-05-21

    complete dependence on nerves. Organ culture of sciatic nerves, combined with an assay for axolotl transferrin developed earlier, allows quantitative study...axonal release of various unknown proteins. Combining this approach with the ELISA for quantitative measurement of axolotl transferrin developed with...light microscope autoradiographic analysis following binding of radiolabelled Tf. Studies of Tf synthesis will employ cDNA probes for axolotl Tf mRNA

  5. Traumatic facial nerve injury.

    PubMed

    Lee, Linda N; Lyford-Pike, Sofia; Boahene, Kofi Derek O

    2013-10-01

    Facial nerve trauma can be a devastating injury resulting in functional deficits and psychological distress. Deciding on the optimal course of treatment for patients with traumatic facial nerve injuries can be challenging, as there are many critical factors to be considered for each patient. Choosing from the great array of therapeutic options available can become overwhelming to both patients and physicians, and in this article, the authors present a systematic approach to help organize the physician's thought process.

  6. Lower cranial nerves.

    PubMed

    Soldatos, Theodoros; Batra, Kiran; Blitz, Ari M; Chhabra, Avneesh

    2014-02-01

    Imaging evaluation of cranial neuropathies requires thorough knowledge of the anatomic, physiologic, and pathologic features of the cranial nerves, as well as detailed clinical information, which is necessary for tailoring the examinations, locating the abnormalities, and interpreting the imaging findings. This article provides clinical, anatomic, and radiological information on lower (7th to 12th) cranial nerves, along with high-resolution magnetic resonance images as a guide for optimal imaging technique, so as to improve the diagnosis of cranial neuropathy.

  7. Optic nerve aspergillosis.

    PubMed

    Yuan, Lisi; Prayson, Richard A

    2015-07-01

    We report a 55-year-old woman with optic nerve Aspergillosis. Aspergillus is an ubiquitous airborne saprophytic fungus. Inhaled Aspergillus conidia are normally eliminated in the immunocompetent host by innate immune mechanisms; however, in immunosuppressed patients, they can cause disease. The woman had a past medical history of hypertension and migraines. She presented 1 year prior to death with a new onset headache behind the left eye and later developed blurred vision and scotoma. A left temporal artery biopsy was negative for giant cell arteritis. One month prior to the current admission, she had an MRI showing optic nerve thickening with no other findings. Because of the visual loss and a positive antinuclear antibody test, she was given a trial of high dose steroids and while it significantly improved her headache, her vision did not improve. At autopsy, the left optic nerve at the level of the cavernous sinus and extending into the optic chiasm was enlarged in diameter and there was a 1.3 cm firm nodule surrounding the left optic nerve. Histologically, an abscess surrounded and involved the left optic nerve. Acute angle branching, angioinvasive fungal hyphae were identified on Grocott's methenamine silver stained sections, consistent with Aspergillus spp. No gross or microscopic evidence of systemic vasculitis or infection was identified in the body. The literature on optic nerve Aspergillosis is reviewed.

  8. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect.

    PubMed

    Luo, Lihua; Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan; Wang, Xiong; Huselstein, Celine; Chen, Yun

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  9. Abnormal Head Position

    MedlinePlus

    ... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

  10. Head injury - first aid

    MedlinePlus

    ... happen from a gunshot to the head. Head injuries include: Concussion , in which the brain is shaken, is the most common type of traumatic brain injury. Scalp wounds. Skull fractures. Head injuries ...

  11. Head circumference (image)

    MedlinePlus

    Head circumference is a measurement of the circumference of the child's head at its largest area (above the eyebrows and ears and around the back of the head). During routine check-ups, the distance is measured ...

  12. [New treatment for peripheral nerve defects: nerve elongation].

    PubMed

    Kou, Y H; Jiang, B G

    2016-10-18

    Peripheral nerve defects are still a major challenge in clinical practice, and the most commonly used method of treatment for peripheral nerve defects is nerve transplantation, which has certain limitations and shortcomings, so new repair methods and techniques are needed. The peripheral nerve is elongated in limb lengthening surgery without injury, from which we got inspirations and proposed a new method to repair peripheral nerve defects: peripheral nerve elongation. The peripheral nerve could beelongated by a certain percent, but the physiological change and the maximum elongation range were still unknown. This study discussed the endurance, the physiological and pathological change of peripheral nerve elongation in detail, and got a lot of useful data. First, we developed peripheral nerve extender which could match the slow and even extension of peripheral nerve. Then, our animal experiment result confirmed that the peripheral nerve had better endurance for chronic elongation than that of acute elongation and cleared the extensibility of peripheral nerve and the range of repair for peripheral nerve defects. Our result also revealed the histological basis and changed the rule for pathological physiology of peripheral nerve elongation: the most important structure foundation of peripheral nerve elongation was Fontana band, which was the coiling of nerve fibers under the epineurium, so peripheral nerve could be stretched for 8.5%-10.0% without injury because of the Fontana band. We confirmed that peripheral nerve extending technology could have the same repair effect as traditional nerve transplantation through animal experiments. Finally, we compared the clinical outcomes between nerve elongation and performance of the conventional method in the repair of short-distance transection injuries in human elbows, and the post-operative follow-up results demonstrated that early neurological function recovery was better in the nerve elongation group than in the

  13. Multiple Heads of Gastrocnemius with Bipennate Fiber Arrangement- A Clinically Significant Variation

    PubMed Central

    Rodrigues, Vincent; Nayak, Shivananda

    2016-01-01

    It is common to have additional muscles or muscle slips in the extremities. Some of them may compress the nerves and vessels or restrict the movements, while others may enhance the muscular activity. However, a small number of them may go unnoticed. Knowledge of such variant muscles becomes important for plastic surgeons while performing various reconstructive surgeries and for clinicians while managing the pain. A case of multiple heads of gastrocnemius muscle was observed during routine dissection of the right lower limb of about 70-year-old male cadaver. It was observed that the medial head of gastrocnemius was attached to the femur with 3 thick heads and lateral head was arising from the lateral condyle of femur by 3 thick heads. All the heads of the muscles remained separate till they formed tendocalcaneus. Some of these heads showed bipinnate fiber arrangement. All the heads were innervated by the branches of tibial nerve. As the muscle heads passed down from their origin, they entrapped the sural nerve and sural nerve was seen emerging at the beginning of tendocalcaneus. Further, detailed literature and the clinical and surgical importance of the case are discussed. PMID:27656426

  14. Vagus Nerve Stimulation in Ischemic Stroke: Old Wine in a New Bottle

    PubMed Central

    Cai, Peter Y.; Bodhit, Aakash; Derequito, Roselle; Ansari, Saeed; Abukhalil, Fawzi; Thenkabail, Spandana; Ganji, Sarah; Saravanapavan, Pradeepan; Shekar, Chandana C.; Bidari, Sharatchandra; Waters, Michael F.; Hedna, Vishnumurthy Shushrutha

    2014-01-01

    Vagus nerve stimulation (VNS) is currently Food and Drug Administration-approved for treatment of both medically refractory partial-onset seizures and severe, recurrent refractory depression, which has failed to respond to medical interventions. Because of its ability to regulate mechanisms well-studied in neuroscience, such as norepinephrine and serotonin release, the vagus nerve may play an important role in regulating cerebral blood flow, edema, inflammation, glutamate excitotoxicity, and neurotrophic processes. There is strong evidence that these same processes are important in stroke pathophysiology. We reviewed the literature for the role of VNS in improving ischemic stroke outcomes by performing a systematic search for publications in Medline (1966–2014) with keywords “VNS AND stroke” in subject headings and key words with no language restrictions. Of the 73 publications retrieved, we identified 7 studies from 3 different research groups that met our final inclusion criteria of research studies addressing the role of VNS in ischemic stroke. Results from these studies suggest that VNS has promising efficacy in reducing stroke volume and attenuating neurological deficits in ischemic stroke models. Given the lack of success in Phase III trials for stroke neuroprotection, it is important to develop new therapies targeting different neuroprotective pathways. Further studies of the possible role of VNS, through normally physiologically active mechanisms, in ischemic stroke therapeutics should be conducted in both animal models and clinical studies. In addition, recent advent of a non-invasive, transcutaneous VNS could provide the potential for easier clinical translation. PMID:25009531

  15. Pituitary adenylatecyclase-activating polypeptide-immunoreactive nerve fibers in the rat epiglottis and pharynx.

    PubMed

    Kano, Mitsuhiro; Shimizu, Yoshinaka; Suzuki, Yujiro; Furukawa, Yusuke; Ishida, Hiroko; Oikawa, Miho; Kanetaka, Hiroyasu; Ichikawa, Hiroyuki; Suzuki, Toshihiko

    2011-12-20

    The distribution of pituitary adenylatecyclase-activating polypeptide-immunoreactive (PACAP-IR) nerve fibers was studied in the rat epiglottis and pharynx. PACAP-IR nerve fibers were located beneath the mucous epithelium, and occasionally penetrated the epithelium. These nerve fibers were abundant on the laryngeal side of the epiglottis and in the dorsal and lateral border region between naso-oral and laryngeal parts of the pharynx. PACAP-IR nerve fibers were also detected in taste buds within the epiglottis and pharynx. In addition, many PACAP-IR nerve fibers were found around acinar cells and blood vessels. The double immunofluorescence method demonstrated that distribution of PACAP-IR nerve fibers was similar to that in CGRP-IR nerve fibers in the epithelium and taste bud. However, distributions of PACAP-IR and CGRP-IR nerve fibers innervating mucous glands and blood vessels were different. The retrograde tracing method also demonstrated that PACAP and CGRP were co-expressed by vagal and glossopharyngeal sensory neurons innervating the pharynx. These findings suggest that PACAP-IR nerve fibers in the epithelium and taste bud of the epiglottis and pharynx which originate from the vagal and glossopharyngeal sensory ganglia include nociceptors and chemoreceptors. The origin of PACAP-IR nerve fibers which innervate mucous glands and blood vessels may be the autonomic ganglion.

  16. Four-headed biceps brachii, three-headed coracobrachialis muscles associated with arterial and nervous anomalies in the upper limb

    PubMed Central

    Catli, Mehmet Mutlu; Ozsoy, Umut; Kaya, Yasemin; Hizay, Arzu; Yildirim, Fatos Belgin

    2012-01-01

    A four-headed biceps brachii muscle and three-headed coracobrachialis muscle, high-originated radial artery and communication between the median and musculocutaneous nerves have been well documented in the available literature. However co-existence of these variations is rare. In this study we aimed to describe multiple variations in the upper limb and discuss their co-existence from clinical and embryological points of view. PMID:22822469

  17. Beta-nerve growth factor levels in newborn cord sera.

    PubMed

    Haddad, J; Vilge, V; Juif, J G; Maitre, M; Donato, L; Messer, J; Mark, J

    1994-06-01

    This study was designed to examine beta-nerve growth factor (NGF) levels in human cord blood by a two-site enzyme immunoassay using MAb 27/21 to mouse NGF and to determine whether beta-NGF levels show developmental changes. Blood was collected at delivery from 61 newborns, 55 neonates appropriate for gestational age (46 term infants and 9 premature infants), 5 neonates small for gestational age, and 1 neonate with congenital hydrocephalus. In addition, samples were collected from 2 microcephalic children (microcephaly vera) aged 15 and 18 mo, 2 control children, and 4 healthy adults. Mean levels of NGF in preterm infants (n = 9; 13.7 +/- 8 pg/mL) were significantly lower than levels in term infants (n = 47; 21.2 +/- 8.8 pg/mL; p = 0.034 by Mann-Whitney U test). There was no correlation between birth weight, length, head circumference, and beta-NGF levels. In microcephalic children, NGF levels were low (8 pg/mL) compared with control infants' values (22 pg/mL). In adults, beta-NGF levels were higher and ranged between 238 and 292 pg/mL. Our study demonstrates that beta-NGF levels can be assessed in human newborn sera using a two-site enzyme immunoassay with MAb 27/21 to mouse beta-NGF, that beta-NGF levels are extremely low in newborns compared with adults, that beta-NGF levels seems to show developmental changes, and that beta-NGF levels may be used to assess NGF utilization under normal and pathologic conditions such as cerebral malformations.

  18. Melanocytoma of the optic nerve head - a diagnostic dilemma

    PubMed Central

    Mohmad, Zalilawati; Kah, Tan Aik; Yong, Ku Chui; Abdul Halim, Wan Haslina Wan; Kong Yong, Then

    2011-01-01

    The clinical features, autofluorescence, B-scan ultrasonography, optical coherence tomography and fluorescein angiography of the lesion were described. Multiple investigation modalities are needed to confirm the benign nature of the lesion. Careful evaluation and follow-up is crucial to avoid misdiagnosis and erroneous management. PMID:24765321

  19. Melanocytoma of the optic nerve head - a diagnostic dilemma.

    PubMed

    Mohmad, Zalilawati; Kah, Tan Aik; Yong, Ku Chui; Abdul Halim, Wan Haslina Wan; Kong Yong, Then

    2011-07-01

    The clinical features, autofluorescence, B-scan ultrasonography, optical coherence tomography and fluorescein angiography of the lesion were described. Multiple investigation modalities are needed to confirm the benign nature of the lesion. Careful evaluation and follow-up is crucial to avoid misdiagnosis and erroneous management.

  20. Heading and head injuries in soccer.

    PubMed

    Kirkendall, D T; Jordan, S E; Garrett, W E

    2001-01-01

    In the world of sports, soccer is unique because of the purposeful use of the unprotected head for controlling and advancing the ball. This skill obviously places the player at risk of head injury and the game does carry some risk. Head injury can be a result of contact of the head with another head (or other body parts), ground, goal post, other unknown objects or even the ball. Such impacts can lead to contusions, fractures, eye injuries, concussions or even, in rare cases, death. Coaches, players, parents and physicians are rightly concerned about the risk of head injury in soccer. Current research shows that selected soccer players have some degree of cognitive dysfunction. It is important to determine the reasons behind such deficits. Purposeful heading has been blamed, but a closer look at the studies that focus on heading has revealed methodological concerns that question the validity of blaming purposeful heading of the ball. The player's history and age (did they play when the ball was leather and could absorb significant amounts of water), alcohol intake, drug intake, learning disabilities, concussion definition and control group use/composition are all factors that cloud the ability to blame purposeful heading. What does seem clear is that a player's history of concussive episodes is a more likely explanation for cognitive deficits. While it is likely that the subconcussive impact of purposeful heading is a doubtful factor in the noted deficits, it is unknown whether multiple subconcussive impacts might have some lingering effects. In addition, it is unknown whether the noted deficits have any affect on daily life. Proper instruction in the technique is critical because if the ball contacts an unprepared head (as in accidental head-ball contacts), the potential for serious injury is possible. To further our understanding of the relationship of heading, head injury and cognitive deficits, we need to: learn more about the actual impact of a ball on the

  1. Blood sugar test - blood

    MedlinePlus

    ... sugar; Blood sugar level; Fasting blood sugar; Glucose test; Diabetic screening - blood sugar test; Diabetes - blood sugar test ... The test may be done in the following ways: After you have not eaten anything for at least 8 ...

  2. Malignant Peripheral Nerve Sheath Tumor -A Rare Malignancy in Mandible

    PubMed Central

    Majumdar, Sumit; Kotina, Sreekanth; Uppala, Divya; Kumar, Singam Praveen

    2016-01-01

    Malignant Peripheral Nerve Sheath Tumor (MPNST) is biologically an aggressive tumor that is usually found in the extremities, trunk and infrequently found in the head and neck area particularly in the jaws, arising from the cells allied with nerve sheath. Mandibular MPNST may either arise from a preexisting neurofibroma or develop de novo. Because of the greater variability from case to case in overall appearance both clinically and histologically, a case of MPNST of the mandible in a 25-year-old female patient is reported. The lesion was excised and immunohistological studies (S-100 & Neuron specific enolase) were conducted to confirm the neural origin. PMID:27504425

  3. Barriers of the peripheral nerve

    PubMed Central

    Peltonen, Sirkku; Alanne, Maria; Peltonen, Juha

    2013-01-01

    This review introduces the traditionally defined anatomic compartments of the peripheral nerves based on light and electron microscopic topography and then explores the cellular and the most recent molecular basis of the different barrier functions operative in peripheral nerves. We also elucidate where, and how, the homeostasis of the normal human peripheral nerve is controlled in situ and how claudin-containing tight junctions contribute to the barriers of peripheral nerve. Also, the human timeline of the development of the barriers of the peripheral nerve is depicted. Finally, potential future therapeutic modalities interfering with the barriers of the peripheral nerve are discussed. PMID:24665400

  4. Neuromuscular ultrasound of cranial nerves.

    PubMed

    Tawfik, Eman A; Walker, Francis O; Cartwright, Michael S

    2015-04-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed.

  5. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect

    SciTech Connect

    Luo, Lihua; Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan; Wang, Xiong; Huselstein, Celine; Chen, Yun

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  6. Genes and nerves.

    PubMed

    Dieu, Tam; Johnstone, Bruce R; Newgreen, Don F

    2005-04-01

    The unpredictability of a brachial plexus graft, a median nerve repair, or a facial-nerve reconstruction is well known. No matter how precise the technical skills, a perfect recovery from a peripheral-nerve lesion is elusive. To resolve this problem, understanding of the normal development of the peripheral nervous system is needed. Presently, the development of the innervation in the upper limb is complex and not fully understood. However, many of the genes involved in this process are now known, and the link between anatomy and genetics is becoming clearer. This short review aims to acquaint the clinical surgeon with some of the main genes. The principal steps in the establishment of neural circuits will be summarized, in particular, the specification and development of neurons and glia, the pathfinding of cells and axons towards their target, and the downstream molecules that control the circuitry of these neurons.

  7. [Lumbosacral nerve bowstring disease].

    PubMed

    Shi, J G; Xu, X M; Sun, J C; Wang, Y; Guo, Y F; Yang, H S; Kong, Q J; Yang, Y; Shi, G D; Yuan, W; Jia, L S

    2017-03-21

    Objective: To define a novel disease-lumbosacral nerve bowstring disease, and propose the diagnostic criteria, while capsule surgery was performed and evaluated in the preliminary study. Methods: From June 2016 to December 2016, a total of 30 patients (22 male and 8 female; mean age of 55.1±9.7 years) with lumbosacral nerve bowstring disease were included in Department of Spine Surgery, Changzheng Hospital, the Second Military Medical University.Lumbosacral nerve bowstring disease was defined as axial hypertension of nerve root and spinal cord caused by congenital anomalies, which could be accompanied by other lesions as lumbar disc herniation, spinal cord stenosis or spondylolisthesis, or aggravated by iatrogenic lesions, resulting in neurological symptoms.This phenomenon is similar to a stretched string, the higher tension on each end the louder sound.Meanwhile, the shape of lumbosacral spine looks like a bow, thus, the disease is nominated as lumbosacral nerve bowstring disease.All the patients underwent capsule surgery and filled out Owestry disability index (ODI) and Tempa scale for kinesiophobia (TSK) before and after surgery. Results: The mean surgery time was (155±36) min, (4.3±0.4) segments were performed surgery.The pre-operative VAS, TSK and ODI scores were (7.6±0.8), (52.0±10.3) and (68.4±12.7), respectively.The post-operative VAS, TSK and ODI scores were (3.3±0.4), ( 24.6±5.2) and (32.1±7.4)(P<0.05, respectively), respectively. Conclusion: The definition and diagnostic criteria of lumbosacral nerve bowstring disease was proposed.Capsule surgery was an effective strategy with most patients acquired excellent outcomes as symptoms relieved and quality of life improved.

  8. Pre-implanted Sensory Nerve Could Enhance the Neurotization in Tissue-Engineered Bone Graft.

    PubMed

    Wu, Yan; Jing, Da; Ouyang, Hongwei; Li, Liang; Zhai, Mingming; Li, Yan; Bi, Long; Guoxian, Pei

    2015-08-01

    In our previous study, it was found that implanting the sensory nerve tract into the tissue-engineered bone to repair large bone defects can significantly result in better osteogenesis effect than tissue-engineered bone graft (TEBG) alone. To study the behavior of the preimplanted sensory nerve in the TEBG, the TEBG was constructed by seeding bone mesenchymal stem cells into β-tricalcium phosphate scaffold with (treatment group) or without (blank group) implantation of the sensory nerve. The expression of calcitonin gene-related peptide (CGRP), which helps in the healing of bone defect in the treatment group was significantly higher than the blank group at 4, 8, and 12 weeks. The expression of growth-associated protein 43 (GAP43), which might be expressed during nerve healing in the treatment group, was significantly higher than the blank group at 4 and 8 weeks. The nerve tracts of the preimplanted sensory nerve were found in the scaffold by the nerve tracing technique. The implanted sensory nerve tracts grew into the pores of scaffolds much earlier than the vascular. The implanted sensory nerve tracts traced by Dil could be observed at 4 weeks, but at the same time, no vascular was observed. In conclusion, the TEBG could be benefited from the preimplanted sensory nerve through the healing behavior of the sensory nerve. The sensory nerve fibers could grow into the pores of the TEBG rapidly, and increase the expression of CGRP, which is helpful in regulating the bone formation and the blood flow.

  9. Comparison of safety and efficiency of microendoscopic discectomy with automatic nerve retractor and with nerve hook

    PubMed Central

    Yin, He-Ping; Wang, Yu-Peng; Qiu, Zhi-Ye; Du, Zhi-Cai; Wu, Yi-Min; Li, Shu-Wen

    2016-01-01

    This study compares the safety and efficiency of two techniques in microendoscopic discectomy (MED) for lumbar disc herniation. The two techniques are MED with automatic nerve retractor and MED with nerve hook which had been widely used for many years. The former involves a newly developed MED device which contains three parts to protect nerve roots during operation. Four hundred and twenty-eight patients underwent MED treatments between October 2010 and September 2015 were recruited and randomized to either intraoperative utilization of automatic nerve retractor (n = 315, group A) or application of nerve hook during surgery (n = 113, group B). Operation time and intraoperative bleeding volume were evaluated. Simultaneously, Visual Analogue Scales (VAS) and muscle strength grading were performed preoperatively, and 1, 2, 3 days, 1, 2 weeks, 3 and 6 months postoperatively. No dramatic difference of pain intensity was observed between the two groups before surgery and 6 months after surgery (P > 0.05). The operation time was shorter in group A (30.30 ± 1.89 min) than that in group B (59.41 ± 3.25 min). Group A (67.83 ± 13.14 ml) experienced a significant decrease in the amount of blood loss volume when compared with group B (100.04 ± 15.10 ml). There were remarkable differences of VAS score and muscle strength grading after postoperative 1, 2, 3 days, 1, 2 weeks and 3 months between both groups (P ≤ 0.05). MED with automatic nerve retractor effectively shortened operation time, decreased the amount of bleeding, down-regulated the incidence of nerve traction injury. PMID:27699062

  10. Nerve Transfers in Tetraplegia.

    PubMed

    Fox, Ida K

    2016-05-01

    Hand and upper extremity function is instrumental to basic activities of daily living and level of independence in cervical spinal cord injury (SCI). Nerve transfer surgery is a novel and alternate approach for restoring function in SCI. This article discusses the biologic basis of nerve transfers in SCI, patient evaluation, management, and surgical approaches. Although the application of this technique is not new; recent case reports and case series in the literature have increased interest in this field. The challenges are to improve function, achieve maximal gains in function, avoid complications, and to primum non nocere.

  11. [Intraneural ganglion of the peroneal nerve. A case report].

    PubMed

    Bischoff, J; Kortmann, K-B; Engelhardt, M

    2010-09-01

    This is a report of a 70-year-old patient with spontaneous pain of the dorsum area of the left foot. A few days later there was a sudden onset of foot drop. First, an idiopathic peroneal palsy was assessed but an MRI showed a cystic tumour near the fibular head. These findings resulted in the patient attending our clinic for surgical treatment. During the operation we found an intraneural ganglion of the deep peroneal nerve and the common peroneal nerve. There was no connection with the superior tibiofibular joint. The ganglion was therefore removed. Two months after the operation the patient reported an improvement of the pain but no improvement of movement of the foot. An intraneural ganglion of the peroneal nerve derives from the superior tibiofibular joint. Given access to the articular branch, the cyst typically spreads out proximally from the deep peroneal nerve to the common peroneal nerve and to the point of the sciatic nerve. The clinical symptoms are correlated with the extent of cyst propagation. Recommended therapy would include the ligation of the aricular branch, or synovectomy, or resection of the superior tibiofibular joint and decompression of the cyst.

  12. Topographical anatomy of the radial nerve and its muscular branches related to surface landmarks.

    PubMed

    Cho, Hyejin; Lee, Hye-Yeon; Gil, Young-Chun; Choi, Yun-Rak; Yang, Hee-Jun

    2013-10-01

    Understanding of the anatomy of the radial nerve and its branches is vital to the treatment of humeral fracture or the restoration of upper extremity function. In this study, we dissected 40 upper extremities from adult cadavers to locate the course of the radial nerve and the origins and insertions of the branches of the radial nerve using surface landmarks. The radial nerve reached and left the radial groove and pierced the lateral intermuscular septum, at the levels of 46.7, 60.5, and 66.8% from the acromion to the transepicondylar line, respectively. Branches to the long head of the triceps brachii originated in the axilla, and branches to the medial and lateral heads originated in the axilla or in the arm. The muscular attachments to the long, medial, and lateral heads were on average 34.0 mm proximal, 16.4 mm distal, and 19.3 mm proximal to the level of inferior end of the deltoid muscle, respectively. The radial nerve innervated 65.0% of the brachialis muscles. Branches to the brachioradialis and those to the extensor carpi radialis longus arose from the radial nerve above the transepicondylar line. Branches to the extensor carpi radialis brevis usually arose from the deep branch of radial nerve (67.5%); however, in some cases, branches to the extensor carpi radialis brevis arose from either the radial nerve (20.0%) or the superficial branch of the radial nerve (12.5%). Using these data, the course of the radial nerve can be estimated by observing the surface of the arm.

  13. Overview of the Cranial Nerves

    MedlinePlus

    ... and toxins. Some cranial nerve disorders interfere with eye movement. Eye movement is controlled by 3 pairs of muscles. These ... be able to move their eyes normally. How eye movement is affected depends on which nerve is affected. ...

  14. Nerve Injuries of the Upper Extremity

    MedlinePlus

    ... of individual nerve fibers and surrounding outer sheath (“insulation”) Figure 2: Nerve repair with realignment of bundles © ... of individual nerve fibers and surrounding outer sheath insulation Figure 2 - Nerve repair with realignment of bundles ...

  15. Blood typing

    MedlinePlus

    ... ABO blood typing; Blood group; Anemia - immune hemolytic blood type; ABO blood type; A blood type; AB blood type; O blood type ... The 2 steps above can accurately determine your blood type. Rh typing uses a method similar to ABO ...

  16. Optic nerve hypoplasia in children.

    PubMed Central

    Zeki, S. M.; Dutton, G. N.

    1990-01-01

    Optic nerve hypoplasia (ONH) is characterised by a diminished number of optic nerve fibres in the optic nerve(s) and until recently was thought to be rare. It may be associated with a wide range of other congenital abnormalities. Its pathology, clinical features, and the conditions associated with it are reviewed. Neuroendocrine disorders should be actively sought in any infant or child with bilateral ONH. Early recognition of the disorder may in some cases be life saving. Images PMID:2191713

  17. Femoral nerve dysfunction

    MedlinePlus

    ... Read More Abscess Diabetes Mononeuropathy Multiple mononeuropathy Myelin Peripheral neuropathy Polyarteritis nodosa Systemic Tumor Review Date 1/5/ ... Related MedlinePlus Health Topics Leg Injuries and Disorders Peripheral Nerve Disorders Browse the Encyclopedia A.D.A.M., Inc. ...

  18. Nerves and Tissue Repair.

    DTIC Science & Technology

    1994-07-01

    axolotl limbs are transected the concentration of transferrin in the distal limb tissue declines rapidly and limb regeneration stops. These results...transferrin binding and expression of the transferrin gene in cells of axolotl peripheral nerve indicate that both uptake and synthesis of this factor occur

  19. Ischemic Nerve Block.

    ERIC Educational Resources Information Center

    Williams, Ian D.

    This experiment investigated the capability for movement and muscle spindle function at successive stages during the development of ischemic nerve block (INB) by pressure cuff. Two male subjects were observed under six randomly ordered conditions. The duration of index finger oscillation to exhaustion, paced at 1.2Hz., was observed on separate…

  20. ANATOMICAL STUDY OF CRANIAL NERVE EMERGENCE AND SKULL FORAMINA IN THE HORSE USING MAGNETIC RESONANCE IMAGING AND COMPUTED TOMOGRAPHY.

    PubMed

    Gonçalves, Rita; Malalana, Fernando; McConnell, James Fraser; Maddox, Thomas

    2015-01-01

    For accurate interpretation of magnetic resonance (MR) images of the equine brain, knowledge of the normal cross-sectional anatomy of the brain and associated structures (such as the cranial nerves) is essential. The purpose of this prospective cadaver study was to describe and compare MRI and computed tomography (CT) anatomy of cranial nerves' origins and associated skull foramina in a sample of five horses. All horses were presented for euthanasia for reasons unrelated to the head. Heads were collected posteuthanasia and T2-weighted MR images were obtained in the transverse, sagittal, and dorsal planes. Thin-slice MR sequences were also acquired using transverse 3D-CISS sequences that allowed mutliplanar reformatting. Transverse thin-slice CT images were acquired and multiplanar reformatting was used to create comparative images. Magnetic resonance imaging consistently allowed visualization of cranial nerves II, V, VII, VIII, and XII in all horses. The cranial nerves III, IV, and VI were identifiable as a group despite difficulties in identification of individual nerves. The group of cranial nerves IX, X, and XI were identified in 4/5 horses although the region where they exited the skull was identified in all cases. The course of nerves II and V could be followed on several slices and the main divisions of cranial nerve V could be distinguished in all cases. In conclusion, CT allowed clear visualization of the skull foramina and occasionally the nerves themselves, facilitating identification of the nerves for comparison with MRI images.

  1. Surgical Outcomes of Inferior Oblique Myectomy in Unilateral Congenital Superior Oblique Palsy with or without Trochlear Nerve

    PubMed Central

    Hwang, Jeong-Min

    2016-01-01

    Objectives To compare the surgical outcomes of inferior oblique (IO) myectomy in congenital superior oblique palsy (SOP) according to the presence of the trochlear nerve identified with high-resolution MRI. Data Extraction Forty-one congenital SOP patients without a trochlear nerve (absent group) and 23 patients with a trochlear nerve (present group) who underwent IO myectomy as the primary surgical treatment were retrospectively reviewed. “Motor success” was defined as postoperative ipsilateral hypertropia ≤ 4 prism diopter (PD). “Head tilt improvement” was regarded as postoperative angle of head tilt < 5 degrees (°). Success rates for motor alignment and head tilt improvement, cumulative probabilities of success, and factors influencing surgical responses were evaluated. Results The cumulative probabilities of motor success at 2 years after IO myectomy were 92% in patients with a trochlear nerve and 86% in patients without a trochlear nerve (P = 0.138). The cumulative probabilities of undercorrection and recurrence of hypertropia after 2 years were 0% in the present group versus 21% in the absent group (P = 0.014). The cumulative probabilities of persistent head tilt after 2 years were 14% in the present group and 20% in the absent group (P = 0.486). A younger age at operation was associated with reduced probabilities of motor success and head tilt improvement (P = 0.009, P = 0.022 respectively). A greater preoperative angle of head tilt was associated with persistent head tilt after surgery (P = 0.038). Conclusions Congenital SOP without a trochlear nerve had a higher risk of hypertropia undercorrection after IO myectomy compared to patients with a trochlear nerve. A younger age at operation and larger preoperative head tilt was related to poor outcomes. PMID:27391445

  2. SU-E-J-241: Wavelet-Based Temporal Feature Extraction From DCE-MRI to Identify Sub-Volumes of Low Blood Volume in Head-And-Neck Cancer

    SciTech Connect

    You, D; Aryal, M; Samuels, S; Eisbruch, A; Cao, Y

    2015-06-15

    Purpose: A previous study showed that large sub-volumes of tumor with low blood volume (BV) (poorly perfused) in head-and-neck (HN) cancers are significantly associated with local-regional failure (LRF) after chemoradiation therapy, and could be targeted with intensified radiation doses. This study aimed to develop an automated and scalable model to extract voxel-wise contrast-enhanced temporal features of dynamic contrastenhanced (DCE) MRI in HN cancers for predicting LRF. Methods: Our model development consists of training and testing stages. The training stage includes preprocessing of individual-voxel DCE curves from tumors for intensity normalization and temporal alignment, temporal feature extraction from the curves, feature selection, and training classifiers. For feature extraction, multiresolution Haar discrete wavelet transformation is applied to each DCE curve to capture temporal contrast-enhanced features. The wavelet coefficients as feature vectors are selected. Support vector machine classifiers are trained to classify tumor voxels having either low or high BV, for which a BV threshold of 7.6% is previously established and used as ground truth. The model is tested by a new dataset. The voxel-wise DCE curves for training and testing were from 14 and 8 patients, respectively. A posterior probability map of the low BV class was created to examine the tumor sub-volume classification. Voxel-wise classification accuracy was computed to evaluate performance of the model. Results: Average classification accuracies were 87.2% for training (10-fold crossvalidation) and 82.5% for testing. The lowest and highest accuracies (patient-wise) were 68.7% and 96.4%, respectively. Posterior probability maps of the low BV class showed the sub-volumes extracted by our model similar to ones defined by the BV maps with most misclassifications occurred near the sub-volume boundaries. Conclusion: This model could be valuable to support adaptive clinical trials with further

  3. Combination treatment of biomechanical support and targeted intra-arterial infusion of peripheral blood stem cells mobilized by granulocyte-colony stimulating factor for the osteonecrosis of the femoral head: a randomized controlled clinical trial.

    PubMed

    Mao, Qiang; Wang, Weidong; Xu, Taotao; Zhang, Shanxing; Xiao, Luwei; Chen, Di; Jin, Hongting; Tong, Peijian

    2015-04-01

    The objective of this study was to determine the benefits of combination treatment with mechanical support and targeted intra-arterial infusion of peripheral blood stem cells (PBSCs) mobilized by granulocyte-colony stimulating factor (G-CSF) via the medial circumflex femoral artery on the progression of osteonecrosis of the femoral head (ONFH). Fifty-five patients (89 hips) with early and intermediate stage ONFH were recruited and randomly assigned to combination treatment or mechanical support treatment (control group). All hips received mechanical support treatment (porous tantalum rod implantation). Then, hips in the combination treatment group were performed targeted intra-arterial infusion of PBSCs. At each follow-up, Harris hip score (HHS) and Association Research Circulation Osseous (ARCO) classification were used to evaluate the symptoms and progression of osteonecrosis. Total hip arthroplasty (THA) was assessed as an endpoint at each follow-up. At 36 months, 9 of the 41 hips (21.95%) in the control group progressed to clinical failure and underwent THA whereas only 3 of the 48 hips (6.25%) in the combination treatment group required THA (p = 0.031). Kaplan-Meier survival analysis showed a significant difference in the survival time between the two groups (log-rank test; p = 0.025). Compared to the control group, combination treatment significantly improved the HHS at 36 months (p = 0.003). At the final follow-up examination, radiological progression was noted in 13 of 41 hips (31.71%) for the control group, but in only 4 of 48 hips (8.33%) for the combination treatment group (p = 0.005). The overall collapse rates were 15.15% (5/33 hips) and 8.11% (3/37 hips) in the control and combination treatment groups, respectively. Targeted intra-arterial infusion of PBSCs is capable of enhancing the efficacy of biomechanical support in the treatment of ONFH. This clinical trial confirmed that the combination treatment might be a safe and feasible

  4. Probabilistic Modeling of Intracranial Pressure Effects on Optic Nerve Biomechanics

    NASA Technical Reports Server (NTRS)

    Ethier, C. R.; Feola, Andrew J.; Raykin, Julia; Myers, Jerry G.; Nelson, Emily S.; Samuels, Brian C.

    2016-01-01

    Altered intracranial pressure (ICP) is involved/implicated in several ocular conditions: papilledema, glaucoma and Visual Impairment and Intracranial Pressure (VIIP) syndrome. The biomechanical effects of altered ICP on optic nerve head (ONH) tissues in these conditions are uncertain but likely important. We have quantified ICP-induced deformations of ONH tissues, using finite element (FE) and probabilistic modeling (Latin Hypercube Simulations (LHS)) to consider a range of tissue properties and relevant pressures.

  5. The radio-radial nerve transfer for elbow extension restoration in C5 to C7 nerve root injury.

    PubMed

    Flores, Leandro Pretto

    2012-01-01

    Extension of the elbow is required to oppose gravity; however, activation of the triceps brachii is frequently underestimated during the surgical planning for brachial plexus injuries. This report aims to describe a novel technique of distal nerve transfer designed for elbow extension reconstruction in patients sustaining a C5-C7 nerve root injury. We report a patient sustaining a brachial plexus injury with triceps palsy and preserved finger extension motion; after careful intraneural dissection of the radial nerve, a fascicle innervating the extensor digitorum communis muscle was sectioned, derouted and connected to a motor branch to the lateral head of the triceps. Eleven months after surgery, elbow extension strength scored MRC M4. No deficits on finger extension were observed.

  6. Donating Blood

    MedlinePlus

    ... blood transfusion. Blood donors — especially donors with certain blood types — are always in demand. Who Can Donate Blood? ... Natural Disasters: How to Help Blood Blood Transfusions Blood Types Contact Us Print Resources Send to a Friend ...

  7. Whole body heating reduces the baroreflex response of sympathetic nerve activity during Valsalva straining.

    PubMed

    Yamazaki, Fumio; Yamauchi, Katsuya; Tsutsui, Yuka; Endo, Yutaka; Sagawa, Sueko; Shiraki, Keizo

    2003-01-31

    The present experiment was carried out to examine the possible effects of whole body heating on the baroreflex control of muscle sympathetic nerve activity (MSNA) and heart rate (HR). Nine healthy male volunteers underwent the Valsalva maneuver during exposure to heat stress using a hot water-perfused suit. To exclude an effect from the unloading of the cardiopulmonary baroreceptors during hyperthermia, the central hypovolemia was counterbalanced by head-down tilt (HDT) at 8 degrees. The baroreflex slopes of MSNA and HR against mean arterial pressure were determined by regression analysis during the early phase II (falling blood pressure period) of the Valsalva maneuver. The core temperature increased from 36.9 +/- 0.1 degrees C at thermoneutral to 37.7 +/- 0.1 degrees C during heat exposure, whereas the left atrial diameter (LAD) decreased. Both the MSNA and HR increased (P < 0.05) during hyperthermia. The baroreflex slopes of MSNA and HR in the phase II decreased 30 +/- 8% (P < 0.05) and 24 +/- 9% (P < 0.05), respectively, during hyperthermia. The HDT increased LAD, but there was no change in HR, arterial pressure and the baroreflex slopes. These results suggest that hyperthermia reduces the baroreflex responses of MSNA and HR during a transient falling period of blood pressure. These reduced baroreflex responses may not be attributable to an unloading of the cardiopulmonary baroreceptors during heat stress.

  8. Retinal hyperaemia-related blood vessel artifacts are relevant to automated OCT layer segmentation.

    PubMed

    Balk, L J; Mayer, M; Uitdehaag, B M J; Petzold, A

    2014-03-01

    A frequently observed local measurement artifact with spectral domain OCT is caused by the void signal of the retinal vasculature. This study investigated the effect of suppression of blood vessel artifacts with and without retinal hyperaemia. Spectral domain OCT scans, centred on the optic nerve head, were performed in 46 healthy subjects (92 eyes). Baseline scans were made during rest, while for the follow-up scan, 23 subjects (50 %) performed strenuous physical exercise. Systemic and retinal hyperaemia were quantified. Quantification of retinal nerve fibre layer (RNFL) thickness was performed with and without suppression of retinal blood vessel artifacts. The potential systematic effect on RNFL thickness measurements was analysed using Bland-Altman plots. At baseline (no retinal hyperaemia), there was a systematic difference in RNFL thickness (3.4 μm, limits of agreement -0.9 to 7.7) with higher values if blood vessel artifacts were not suppressed. There was significant retinal hyperaemia in the exercise group (p < 0.0001). Baseline thickness increased from 93.18 to 93.83 μm (p < 0.05) in the exercise group using the algorithm with blood vessel artifact suppression, but no significant changes were observed using the algorithm without blood vessel artifact suppression. Retinal hyperaemia leads to blood vessel artifacts which are relevant to the precision of OCT layer segmentation algorithms. The two algorithms investigated in this study can not be used interchangeably. The algorithm with blood vessel artifact suppression was more sensitive in detecting small changes in RNFL thickness. This may be relevant for the use of OCT in a range of neurodegenerative diseases were only a small degree of retinal layer atrophy have been found so far.

  9. Nerve root replantation.

    PubMed

    Carlstedt, Thomas

    2009-01-01

    Traumatic avulsion of nerve roots from the spinal cord is a devastating event that usually occurs in the brachial plexus of young adults following motor vehicle or sports accidents or in newborn children during difficult childbirth. A strategy to restore motor function in the affected arm by reimplanting into the spinal cord the avulsed ventral roots or autologous nerve grafts connected distally to the avulsed roots has been developed. Surgical outcome is good and useful recovery in shoulder and proximal arm muscles occurs. Pain is alleviated with motor recovery but sensory improvement is poor when only motor conduits have been reconstructed. In experimental studies, restoration of sensory connections with general improvement in the outcome from this surgery is pursued.

  10. Head CT scan

    MedlinePlus

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... conditions: Birth (congenital) defect of the head or brain Brain infection Brain tumor Buildup of fluid inside ...

  11. Head and Neck Cancer

    MedlinePlus

    Head and neck cancer includes cancers of the mouth, nose, sinuses, salivary glands, throat, and lymph nodes in the ... swallowing A change or hoarseness in the voice Head and neck cancers are twice as common in men. Using ...

  12. Increased head circumference

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003305.htm Increased head circumference To use the sharing features on this page, please enable JavaScript. Increased head circumference is when the measured distance around the ...

  13. The role of OCT in the differential diagnosis between buried optic nerve drusen and papilloedema.

    PubMed

    Rebolleda, G; Muñoz-Negrete, F J

    2016-09-01

    Buried optic nerve head drusen are one of the most common causes of pseudo-papilloedema. In this review, we have chronologically addressed several useful traits in the differential diagnosis of a true papilloedema, using the different features of optical coherence tomography (OCT). The specificity of these features has improved at the same time as the improvement in penetration capability and resolution of newer OCT devices. Spectral domain OCT, and more specifically the enhanced depth imaging (EDI) technology, represents a turning point in directly visualise drusen, to quantify their size and to recognise their impact on neighbouring structures inside the optic nerve head.

  14. Cranial nerves in the Australian lungfish, Neoceratodus forsteri, and in fossil relatives (Osteichthyes: Dipnoi).

    PubMed

    Kemp, A

    2017-02-01

    Three systems, two sensory and one protective, are present in the skin of the living Australian lungfish, Neoceratodus forsteri, and in fossil lungfish, and the arrangement and innervation of the sense organs is peculiar to lungfish. Peripheral branches of nerves that innervate the sense organs are slender and unprotected, and form before any skeletal structures appear. When the olfactory capsule develops, it traps some of the anterior branches of cranial nerve V, which emerged from the chondrocranium from the lateral sphenotic foramen. Cranial nerve I innervates the olfactory organ enclosed within the olfactory capsule and cranial nerve II innervates the eye. Cranial nerve V innervates the sense organs of the snout and upper lip, and, in conjunction with nerve IX and X, the sense organs of the posterior and lateral head. Cranial nerve VII is primarily a motor nerve, and a single branch innervates sense organs in the mandible. There are no connections between nerves V and VII, although both emerge from the brain close to each other. The third associated system consists of lymphatic vessels covered by an extracellular matrix of collagen, mineralised as tubules in fossils. Innervation of the sensory organs is separate from the lymphatic system and from the tubule system of fossil lungfish.

  15. Intraoperative Assessment of Facial Nerve Trunk Width in Early Childhood With Cervicofacial Lymphatic Malformation

    PubMed Central

    Kim, Ara; Seo, Jeong-Meen; Lim, So Young

    2017-01-01

    Background Facial nerve damage during head and neck surgery has long been an important issue. However, few publications on the gross anatomy of the facial nerve are available in the young population. The aim of this study was to provide in vivo measurements of the facial nerve trunk during lymphatic malformation (LM) resection and to determine the association between the trunk width and patient- and disease-related variables. Methods We conducted a retrospective analysis of 11 consecutive pediatric patients (11 facial nerve trunks) who underwent cervicofacial LM resection. The facial nerve of the affected side was dissected, and its trunk width at bifurcation was measured using calipers under a microscope during the operation. Results Eleven patients younger than 6 years were enrolled. The median width of the facial nerve in patients younger than 1 year was 1.15 mm; it was 2.5 mm in those older than 1 year. Trunk width was significantly greater in patients older than 1 year than those younger than 1 year, whereas no statistical significance was found when comparing other age groups. Patient weight was positively correlated with trunk width, whereas LM grade and diameter showed no significant correlation. Conclusions The significantly greater width of the facial nerve trunk in LM patients older than 1 year than those younger than 1 year suggests that the age of 1 may be a threshold for facial nerve hypertrophy and growth acceleration. This study provides informative in vivo data to help understand facial nerve characteristics in young patients. PMID:27922488

  16. Intraoral Neurinoma of the Lingual Nerve: An Uncommon Tumor in Floor of the Mouth

    PubMed Central

    Kumar kuppusamy, Santhosh; Ramkumar, Subramaniyam; Narasimhan, Malathi; Azariah Dhiravia Sargunam, Emmanuel

    2014-01-01

    Neurinoma or schwannoma is an uncommon benign tumor that arises primarily from the nerve sheath of Schwann cells. About 25% has been reported in head and neck region extracranially, but only 1% in the intraoral origin. Intraorally, the tongue is the most common site followed by the palate, floor of the mouth, lips and buccal mucosa. In review of literature, intraoral schwannoma of the lingual nerve origin has not been reported frequently. So, we present a case of intraoral neurinoma of the lingual nerve. PMID:24639903

  17. Isolated glossopharyngeal and vagus nerves palsy due to fracture involving the left jugular foramen.

    PubMed

    Alberio, N; Cultrera, F; Antonelli, V; Servadei, F

    2005-07-01

    This report describes a case of delayed post-traumatic glossopharyngeal and vagus nerves palsy (i.e. dysphonia and swallowing dysfunction). A high resolution CT study of the cranial base detected a fracture rim encroaching on the left jugular foramen. Treatment consisted in supportive measures with incomplete recovery during a one-year follow-up period. Lower cranial nerves palsies after head trauma are rare and, should they occur, a thorough investigation in search of posterior cranial base and cranio-cervical lesions is warranted. The presumptive mechanism in our case is a fracture-related oedema and ischemic damage to the nerves leading to the delayed occurrence of the palsy.

  18. Cardiopulmonary baroreflex inhibition of sympathetic nerve activity is preserved with age in healthy humans.

    PubMed

    Tanaka, H; Davy, K P; Seals, D R

    1999-02-15

    1. We tested the hypothesis that the ability of the cardiopulmonary baroreflex to produce sympathoinhibition is reduced with age in humans. Eleven young (23 +/- 1 years, mean +/- s.e.m.) and ten older (64 +/- 1) healthy adult males were studied under supine conditions (control) and in response to cardiopulmonary baroreflex stimulation evoked by acute central circulatory hypervolaemia (10 deg head-down tilt). The two groups were normotensive and free of overt cardiovascular disease. 2. Supine baseline (control) levels of efferent muscle sympathetic nerve activity (MSNA) burst frequency were twice as high in the older men (41 +/- 2 vs. 21 +/- 2 bursts min-1, P < 0.05). In both groups in response to head-down tilt arterial blood pressure and heart rate were unchanged, peripheral venous pressure (PVP) increased (P < 0.05), MSNA total activity decreased (P < 0.05), antecubital venous plasma noradrenaline concentrations did not change significantly, and forearm blood flow and vascular conductance increased (vascular resistance decreased) (all P < 0.05). The mean absolute DeltaMSNA/DeltaPVP was similar in the young and older men, although the higher control levels of MSNA in the older men resulted in a smaller percentage DeltaMSNA/DeltaPVP (P < 0.05). Per DeltaPVP, the reduction in forearm vascular resistance was smaller in the older men, but there were no age group differences when expressed as increases in forearm vascular conductance. 3. These results indicate that the ability of the cardiopulmonary baroreflex to inhibit MSNA is well preserved with age in healthy adult humans. As such, these findings are not consistent with the concept that this mechanism plays a role in the age-associated elevation in basal MSNA.

  19. The Head Start Debates

    ERIC Educational Resources Information Center

    Zigler, Edward, Ed.; Styfco, Sally J., Ed.

    2004-01-01

    The future of Head Start depends on how well people learn from and apply the lessons from its past. That's why everyone involved in early education needs this timely, forward-thinking book from the leader of Head Start. The first book to capture the Head Start debates in all their complexity and diversity, this landmark volume brings together the…

  20. Mania following head injury.

    PubMed

    Yatham, L N; Benbow, J C; Jeffers, A M

    1988-03-01

    A case of mania following head injury in an individual with a genetic predisposition to schizophrenia is reported. It is argued that the head injury is probably causative in his case and suggested that head injury should be considered as one of the aetiological factors in secondary mania.

  1. Head and Neck Cancer

    MedlinePlus

    ... a person’s risk of head and neck cancer. Marijuana use. Research suggests that people who have used marijuana may be at higher risk for head and ... head and neck cancer include: Avoiding alcohol Discussing marijuana as a risk factor with your doctor and ...

  2. Head Start Automation Manual.

    ERIC Educational Resources Information Center

    Maryland Univ., College Park. Univ. Coll.

    The task for the National Data Management Project is to share technological capabilities with the Head Start Community in order to implement improved services for children and families involved in Head Start. Many Head Start programs have incorporated technology into their programs, including word processing, database management systems,…

  3. Head Injury Prevention Tips

    MedlinePlus

    ... Fax: 847-378-0600 www.NeurosurgeryToday.org A traumatic brain injury (TBI) is defined as a blow or jolt to the head or a penetrating head injury that disrupts the normal function of the brain. TBI can result when the head suddenly and ...

  4. Histomorphometric measurements in human and dog optic nerve and an estimation of optic nerve pressure gradients in human.

    PubMed

    Balaratnasingam, Chandrakumar; Morgan, William H; Johnstone, Victoria; Pandav, Surinder S; Cringle, Stephen J; Yu, Dao-Yi

    2009-11-01

    Intraocular pressure and cerebrospinal fluid (CSF) pressure are important determinants of the trans-laminar pressure gradient which is believed to be important in the pathogenesis of glaucomatous optic nerve degeneration. Computational models and finite element calculations of optic nerve head biomechanics have been previously used to predict pressures and stresses in the human optic nerve. The purpose of this report is to morphometrically compare the optic nerve laminar and pia mater structure between humans and dogs, and to use previously reported tissue pressure measurements in the dog optic nerve to estimate individual-specific human optic nerve pressures and pressure gradients. High resolution light microscopy was used to acquire quantitative histological measurements from sagittal sections taken from the middle of the optic nerve in 34 human cadaveric eyes and 10 dog eyes. Parameters measured included the pre-laminar and lamina cribrosa thickness, distance from posterior boundary of lamina cribrosa to inner limiting membrane (ILM), shortest distance between anterior lamina cribrosa surface and subarachnoid space, shortest distance between ILM and inner surface of pia mater in contact with the subarachnoid space and optic nerve diameter. Pia mater thickness in the proximal 4 mm of post-laminar nerve was also determined. There was no significant difference in lamina cribrosa thickness between dog and human eyes (P = 0.356). The distance between the intraocular and subarachnoid space was greater in dogs (P < 0.001). Pia mater thickness was greatest at the termination of subarachnoid space in both species. In humans, pia mater thickness decreased over the proximal 500 mum to reach a constant value of approximately 60 mum. In dogs this decrease occurred over 1000 mum to reach a constant diameter of approximately 30 mum. Using previous measurements of optic nerve pressures and pressure gradients in dogs we estimate that at an IOP of 15 mmHg and a CSF pressure of 0

  5. Distribution of sensory nerve endings around the human sinus tarsi: a cadaver study.

    PubMed

    Rein, Susanne; Manthey, Suzanne; Zwipp, Hans; Witt, Andreas

    2014-04-01

    The aim of this study was to analyse the pattern of sensory nerve endings and blood vessels around the sinus tarsi. The superficial and deep parts of the fat pads at the inferior extensor retinaculum (IER) as well as the subtalar joint capsule inside the sinus tarsi from 13 cadaver feet were dissected. The distribution of the sensory nerve endings and blood vessels were analysed in the resected specimens as the number per cm(2) after staining with haematoxylin-eosin, S100 protein, low-affinity neurotrophin receptor p75, and protein gene product 9.5 using the classification of Freeman and Wyke. Free nerve endings were the predominant sensory ending (P < 0.001). Ruffini and Golgi-like endings were rarely found and no Pacini corpuscles were seen. Significantly more free nerve endings (P < 0.001) and blood vessels (P = 0.01) were observed in the subtalar joint capsule than in the superficial part of the fat pad at the IER. The deep part of the fat pad at the IER had significantly more blood vessels than the superficial part of the fat pad at the IER (P = 0.012). Significantly more blood vessels than free nerve endings were seen in all three groups (P < 0.001). No significant differences in distribution were seen in terms of right or left side, except for free nerve endings in the superficial part of the fat pad at the IER (P = 0.003). A greater number of free nerve endings correlated with a greater number of blood vessels. The presence of sensory nerve endings between individual fat cells supports the hypothesis that the fat pad has a proprioceptive role monitoring changes and that it is a source of pain in sinus tarsi syndrome due to the abundance of free nerve endings.

  6. Abducens nerve palsy due to inferior petrosal sinus thrombosis.

    PubMed

    Mittal, Shivam Om; Siddiqui, Junaid; Katirji, Bashar

    2017-02-24

    Isolated unilateral abducens nerve palsy is usually due to ischemia, trauma or neoplasm. Dorello's canal is the space between the petrous apex and superolateral portion of the clivus, bound superiorly by Gruber's ligament. The abducens nerve travels with inferior petrosal sinus (IPS) though the Dorello's canal before entering the cavernous sinus. A 31-year-old man presented with neck pain, and binocular horizontal diplopia, worse looking towards left and at distance. He had a history of intravenous drug abuse but no history of hypertension or diabetes. On examination, he had complete left 6th nerve palsy with normal fundi, pupils, and other cranial nerves. Methicillin-resistant Staphylococcus aureus bacteremia was detected with naïve tricuspid valve endocarditis and multiple septic emboli to lungs with infarcts. His cerebrospinal fluid was normal. MRI of the brain was normal. MRV of head and neck showed thrombosis of the left internal jugular vein, left sigmoid sinus and left inferior petrosal sinus with normal cavernous sinus and no evidence of mastoiditis. He was treated with broad spectrum antibiotics. He was not anticoagulated for fear of pulmonary hemorrhage from pulmonary infarcts. Although cerebral venous sinus thrombosis commonly presents with elevated intracranial pressure, isolated ipsilateral 6th nerve palsy from its compression in Dorello's canal due to thrombosis of the ipsilateral inferior petrosal sinus is extremely rare. To our knowledge, only two patients have been reported with isolated abducens palsy due to IPS thrombosis; one caused by septic emboli and the other developed it during IPS cortisol level sampling.

  7. High spatial resolution imaging mass spectrometry of human optic nerve lipids and proteins.

    PubMed

    Anderson, David M G; Spraggins, Jeffrey M; Rose, Kristie L; Schey, Kevin L

    2015-06-01

    The human optic nerve carries signals from the retina to the visual cortex of the brain. Each optic nerve is comprised of approximately one million nerve fibers that are organized into bundles of 800-1200 fibers surrounded by connective tissue and supportive glial cells. Damage to the optic nerve contributes to a number of blinding diseases including: glaucoma, neuromyelitis optica, optic neuritis, and neurofibromatosis; however, the molecular mechanisms of optic nerve damage and death are incompletely understood. Herein we present high spatial resolution MALDI imaging mass spectrometry (IMS) analysis of lipids and proteins to define the molecular anatomy of the human optic nerve. The localization of a number of lipids was observed in discrete anatomical regions corresponding to myelinated and unmyelinated nerve regions as well as to supporting connective tissue, glial cells, and blood vessels. A protein fragment from vimentin, a known intermediate filament marker for astrocytes, was observed surrounding nerved fiber bundles in the lamina cribrosa region. S100B was also found in supporting glial cell regions in the prelaminar region, and the hemoglobin alpha subunit was observed in blood vessel areas. The molecular anatomy of the optic nerve defined by MALDI IMS provides a firm foundation to study biochemical changes in blinding human diseases.

  8. High Spatial Resolution Imaging Mass Spectrometry of Human Optic Nerve Lipids and Proteins

    NASA Astrophysics Data System (ADS)

    Anderson, David M. G.; Spraggins, Jeffrey M.; Rose, Kristie L.; Schey, Kevin L.

    2015-06-01

    The human optic nerve carries signals from the retina to the visual cortex of the brain. Each optic nerve is comprised of approximately one million nerve fibers that are organized into bundles of 800-1200 fibers surrounded by connective tissue and supportive glial cells. Damage to the optic nerve contributes to a number of blinding diseases including: glaucoma, neuromyelitis optica, optic neuritis, and neurofibromatosis; however, the molecular mechanisms of optic nerve damage and death are incompletely understood. Herein we present high spatial resolution MALDI imaging mass spectrometry (IMS) analysis of lipids and proteins to define the molecular anatomy of the human optic nerve. The localization of a number of lipids was observed in discrete anatomical regions corresponding to myelinated and unmyelinated nerve regions as well as to supporting connective tissue, glial cells, and blood vessels. A protein fragment from vimentin, a known intermediate filament marker for astrocytes, was observed surrounding nerved fiber bundles in the lamina cribrosa region. S100B was also found in supporting glial cell regions in the prelaminar region, and the hemoglobin alpha subunit was observed in blood vessel areas. The molecular anatomy of the optic nerve defined by MALDI IMS provides a firm foundation to study biochemical changes in blinding human diseases.

  9. Peripheral Nerve Injury: Stem Cell Therapy and Peripheral Nerve Transfer

    PubMed Central

    Sullivan, Robert; Dailey, Travis; Duncan, Kelsey; Abel, Naomi; Borlongan, Cesario V.

    2016-01-01

    Peripheral nerve injury can lead to great morbidity in those afflicted, ranging from sensory loss, motor loss, chronic pain, or a combination of deficits. Over time, research has investigated neuronal molecular mechanisms implicated in nerve damage, classified nerve injury, and developed surgical techniques for treatment. Despite these advancements, full functional recovery remains less than ideal. In this review, we discuss historical aspects of peripheral nerve injury and introduce nerve transfer as a therapeutic option, as well as an adjunct therapy to transplantation of Schwann cells and their stem cell derivatives for repair of the damaged nerve. This review furthermore, will provide an elaborated discussion on the sources of Schwann cells, including sites to harvest their progenitor and stem cell lines. This reflects the accessibility to an additional, concurrent treatment approach with nerve transfers that, predicated on related research, may increase the efficacy of the current approach. We then discuss the experimental and clinical investigations of both Schwann cells and nerve transfer that are underway. Lastly, we provide the necessary consideration that these two lines of therapeutic approaches should not be exclusive, but conversely, should be pursued as a combined modality given their mutual role in peripheral nerve regeneration. PMID:27983642

  10. Nerve regeneration in nerve grafts conditioned by vibration exposure.

    PubMed

    Bergman, S; Widerberg, A; Danielsen, N; Lundborg, G; Dahlin, L B

    1995-01-01

    Regeneration distances were studied in nerves from vibration-exposed limbs. One hind limb of anaesthetized rats was attached to a vibration exciter and exposed to vibration (80 Hz/32 m/s2) for 5 h/day for 2 or 5 days. Seven days after the latest vibration period a 10-mm long nerve graft was taken from the vibrated sciatic nerve and sutured into a corresponding defect in the con-tralateral sciatic nerve and vice versa, thereby creating two different models within the same animal: (i) regeneration from a freshly transected unvibrated nerve into a vibrated graft and (ii) regeneration from a vibrated nerve into a fresh nerve graft (vibrated recipient side). Four, 6 or 8 days postoperatively (p.o.) the distances achieved by the regenerating axons were determined using the pinch reflex test. Two days of vibration did not influence the regeneration, but 5 days of vibration reduced the initial delay period and a slight reduction of regeneration rate was observed. After 5 days of vibration an increased regeneration distance was observed in both models at day 4 p.o. and at day 6 p.o. in vibrated grafts. This study demonstrates that vibration can condition peripheral nerves and this may be caused by local changes in the peripheral nerve trunk and in the neuron itself.

  11. Primary amyloidosis presenting as "dropped head syndrome".

    PubMed

    Chuquilin, Miguel; Al-Lozi, Muhammad

    2011-06-01

    A 77-year-old man, with a history of lymphoma, presented with isolated neck extensor weakness and a 2-year history of bilateral carpal tunnel syndrome (CTS). Needle electromyography showed myopathic changes, and biopsy of cervical paraspinal muscles showed amyloid deposition in blood vessels. Amyloidosis should be considered in the differential diagnosis of dropped head syndrome.

  12. Management of peripheral facial nerve palsy.

    PubMed

    Finsterer, Josef

    2008-07-01

    Peripheral facial nerve palsy (FNP) may (secondary FNP) or may not have a detectable cause (Bell's palsy). Three quarters of peripheral FNP are primary and one quarter secondary. The most prevalent causes of secondary FNP are systemic viral infections, trauma, surgery, diabetes, local infections, tumor, immunological disorders, or drugs. The diagnosis of FNP relies upon the presence of typical symptoms and signs, blood chemical investigations, cerebro-spinal-fluid-investigations, X-ray of the scull and mastoid, cerebral MRI, or nerve conduction studies. Bell's palsy may be diagnosed after exclusion of all secondary causes, but causes of secondary FNP and Bell's palsy may coexist. Treatment of secondary FNP is based on the therapy of the underlying disorder. Treatment of Bell's palsy is controversial due to the lack of large, randomized, controlled, prospective studies. There are indications that steroids or antiviral agents are beneficial but also studies, which show no beneficial effect. Additional measures include eye protection, physiotherapy, acupuncture, botulinum toxin, or possibly surgery. Prognosis of Bell's palsy is fair with complete recovery in about 80% of the cases, 15% experience some kind of permanent nerve damage and 5% remain with severe sequelae.

  13. Visceral nerves: vagal and sympathetic innervation.

    PubMed

    Teff, Karen L

    2008-01-01

    The autonomic nervous system is the primary neural mediator of physiological responses to internal and external stimuli. It is composed of 2 branches: the sympathetic nervous system, which mediates catabolic responses, and the parasympathetic nervous system, composed of the vagus nerve, which regulates anabolic responses. As the vagus nerve innervates most tissues involved in nutrient metabolism, including the stomach, pancreas, and liver, activation of vagal efferent activity has the potential to influence how nutrients are absorbed and metabolized. Vagal efferent activity is initially activated at the onset of food intake by receptors in the oropharyngeal cavity and then during food intake postprandially. Vagal efferent innervation of the pancreas contributes to early-phase insulin release as well as to optimizing postprandial insulin release. In the absence of vagal activation, which occurs when glucose is administered intragastrically, postprandial glucose levels are higher and insulin levels blunted compared with when there is activation of oropharyngeal receptors by food. An induction of vagal efferent activity also occurs during chronic pancreatic B-cell challenge with 48-hour glucose infusions. Under these conditions, the compensatory increase in insulin secretion is partially mediated by an increase in vagal efferent activity. In conclusion, the vagus nerve, part of the parasympathetic nervous system, plays a critical role in the regulation of blood glucose levels and is an often overlooked factor contributing to glucose homeostasis.

  14. The complex interaction between ocular perfusion pressure and ocular blood flow - relevance for glaucoma.

    PubMed

    Schmidl, Doreen; Garhofer, Gerhard; Schmetterer, Leopold

    2011-08-01

    Glaucoma is an optic neuropathy of unknown origin. The most important risk factor for the disease is an increased intraocular pressure (IOP). Reducing IOP is associated with reduced progression in glaucoma. Several recent large scale trials have indicated that low ocular perfusion pressure (OPP) is a risk factor for the incidence, prevalence and progression of the disease. This is a strong indicator that vascular factors are involved in the pathogenesis of the disease, a hypothesis that was formulated 150 years ago. The relation between OPP and blood flow to the posterior pole of the eye is, however, complex, because of a phenomenon called autoregulation. Autoregulatory processes attempt to keep blood flow constant despite changes in OPP. Although autoregulation has been observed in many experiments in the ocular vasculature the mechanisms underlying the vasodilator and vasoconstrictor responses in face of changes in OPP remain largely unknown. There is, however, recent evidence that the human choroid regulates its blood flow better during changes in blood pressure induced by isometric exercise than during changes in IOP induced by a suction cup. This may have consequences for our understanding of glaucoma, because it indicates that blood flow regulation is strongly dependent not only on OPP, but also on the level of IOP itself. Indeed there is data indicating that reduction of IOP by pharmacological intervention improves optic nerve head blood flow regulation independently of an ocular vasodilator effect.

  15. Neuromuscular Ultrasound of Cranial Nerves

    PubMed Central

    Tawfik, Eman A.; Cartwright, Michael S.

    2015-01-01

    Ultrasound of cranial nerves is a novel subdomain of neuromuscular ultrasound (NMUS) which may provide additional value in the assessment of cranial nerves in different neuromuscular disorders. Whilst NMUS of peripheral nerves has been studied, NMUS of cranial nerves is considered in its initial stage of research, thus, there is a need to summarize the research results achieved to date. Detailed scanning protocols, which assist in mastery of the techniques, are briefly mentioned in the few reference textbooks available in the field. This review article focuses on ultrasound scanning techniques of the 4 accessible cranial nerves: optic, facial, vagus and spinal accessory nerves. The relevant literatures and potential future applications are discussed. PMID:25851889

  16. Head and Neck Cancer Treatment

    MedlinePlus

    ... News Physician Resources Professions Site Index A-Z Head and Neck Cancer Treatment Head and neck cancer overview What ... there any new developments in treating my disease? Head and neck cancer overview The way a particular head and ...

  17. Head, Neck, and Oral Cancer

    MedlinePlus

    ... find out more. Head, Neck and Oral Pathology Head, Neck and Oral Pathology Close to 49,750 Americans ... find out more. Head, Neck and Oral Pathology Head, Neck and Oral Pathology Close to 49,750 Americans ...

  18. Intercostal nerve blockade for evaluation of local anaesthetic agents.

    PubMed

    Bridenbaugh, P O

    1975-02-01

    Bilateral intercostal nerve block provides the opportunity to subject as many as 16 separate peripheral nerves in a single subject to known or unknown local anaesthetic agents in a variety of concentrations, volumes, and additives. It permits the observation of local (e.g., neuritis), clinical (e.g., onset and duration), and systemic (e.g., toxicity and blood concentration) effects of these variables. In double-blind studies, bilateral intercostal nerve block allows the use of each side of the trunk for comparison of two experimental drugs, a new drug against a standard, or two new drugs. Subtle differences in clinical properties as well as simultaneous blood concentrations may be detected in these studies. The advantages of this technique in evaluating local anaesthetic agents are primarily the use of a single subject as his own control while studying may separate peripheral nerves. This aids appreciably in limiting the variable of age, temperature, and perfusion, as well as techniques of administration and evaluation. The constancy of the anatomy of the intercostal nerve provides a highly reliable and reproducible block technique.

  19. Patterning of sympathetic nerve activity in response to vestibular stimulation

    NASA Technical Reports Server (NTRS)

    Kerman, I. A.; McAllen, R. M.; Yates, B. J.

    2000-01-01

    Growing evidence suggests a role for the vestibular system in regulation of autonomic outflow during postural adjustments. In the present paper we review evidence for the patterning of sympathetic nerve activity elicited by vestibular stimulation. In response to electrical activation of vestibular afferents, firing of sympathetic nerves located throughout the body is altered. However, activity of the renal nerve is most sensitive to vestibular inputs. In contrast, high-intensity simultaneous activation of cutaneous and muscle inputs elicits equivalent changes in firing of the renal, superior mesenteric and lumbar colonic nerves. Responses of muscle vasoconstrictor (MVC) efferents to vestibular stimulation are either inhibitory (Type I) or are comprised of a combination of excitation and inhibition (Type II). Interestingly, single MVC units located in the hindlimb exhibited predominantly Type I responses while those located in the forelimb and face exhibited Type II responses. Furthermore, brachial and femoral arterial blood flows were dissociated in response to vestibular stimulation, such that brachial vascular resistance increased while femoral resistance decreased. These studies demonstrate that vestibulosympathetic reflexes are patterned according to both the anatomical location and innervation target of a particular sympathetic nerve, and can lead to distinct changes in local blood flow.

  20. Contralateral genitofemoral sympathetic nerve discharge increases following ipsilateral testicular torsion.

    PubMed

    Otçu, Selçuk; Durakoğugil, Murat; Orer, Hakan S; Tanyel, Feridun C

    2002-10-01

    The decrease in blood flow due to the activation of sympathetic system has been suggested to play a role in contralateral testicular deterioration associated with unilateral testicular torsion. Sympathetic nerve discharges (SND) from the genitofemoral nerve were evaluated before and during unilateral testicular torsion. Under urethane anesthesia, arterial blood pressure and SND from splanchnic and right genitofemoral nerves were recorded in 12 male Sprague-Dawley rats, 8 of which were included in subsequent analyses. After control recordings of basal discharges for 2 min the left testis was twisted 720 degrees counterclockwise, and recording was resumed for an additional 30 min. Changes in nerve activity were calculated by measuring the area under the autospectrum curve, and alterations were compared. Following testicular torsion no significant changes were obtained for splanchnic SND, but the amplitude of SND from contralateral genitofemoral nerve showed an overall increase of 21.20+/-7.03% in six rats. This increase lasted about 10-15 min and activities returned to pretorsion levels. In two other rats no significant change was observed in either splanchnic or genitofemoral SND. Ipsilateral testicular torsion results in a transient increase in genitofemoral SND. A possible autonomic reflex mechanism may exist, and it may be activated by noxious stimuli from contralateral side. This reflex mechanism may initiate a series of events that lead to the injury of contralateral testis.

  1. Nerve Cross-Bridging to Enhance Nerve Regeneration in a Rat Model of Delayed Nerve Repair

    PubMed Central

    2015-01-01

    There are currently no available options to promote nerve regeneration through chronically denervated distal nerve stumps. Here we used a rat model of delayed nerve repair asking of prior insertion of side-to-side cross-bridges between a donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) nerve stump ameliorates poor nerve regeneration. First, numbers of retrogradely-labelled TIB neurons that grew axons into the nerve stump within three months, increased with the size of the perineurial windows opened in the TIB and CP nerves. Equal numbers of donor TIB axons regenerated into CP stumps either side of the cross-bridges, not being affected by target neurotrophic effects, or by removing the perineurium to insert 5-9 cross-bridges. Second, CP nerve stumps were coapted three months after inserting 0-9 cross-bridges and the number of 1) CP neurons that regenerated their axons within three months or 2) CP motor nerves that reinnervated the extensor digitorum longus (EDL) muscle within five months was determined by counting and motor unit number estimation (MUNE), respectively. We found that three but not more cross-bridges promoted the regeneration of axons and reinnervation of EDL muscle by all the CP motoneurons as compared to only 33% regenerating their axons when no cross-bridges were inserted. The same 3-fold increase in sensory nerve regeneration was found. In conclusion, side-to-side cross-bridges ameliorate poor regeneration after delayed nerve repair possibly by sustaining the growth-permissive state of denervated nerve stumps. Such autografts may be used in human repair surgery to improve outcomes after unavoidable delays. PMID:26016986

  2. Peptide therapy with pentadecapeptide BPC 157 in traumatic nerve injury.

    PubMed

    Gjurasin, Miroslav; Miklic, Pavle; Zupancic, Bozidar; Perovic, Darko; Zarkovic, Kamelija; Brcic, Luka; Kolenc, Danijela; Radic, Bozo; Seiwerth, Sven; Sikiric, Predrag

    2010-02-25

    We focused on the healing of rat transected sciatic nerve and improvement made by stable gastric pentadecapeptide BPC 157 (10 microg, 10ng/kg) applied shortly after injury (i) intraperitoneally/intragastrically/locally, at the site of anastomosis, or after (ii) non-anastomozed nerve tubing (7 mm nerve segment resected) directly into the tube. Improvement was shown clinically (autotomy), microscopically/morphometrically and functionally (EMG, one or two months post-injury, walking recovery (sciatic functional index (SFI)) at weekly intervals). BPC 157-rats exhibited faster axonal regeneration: histomorphometrically (improved presentation of neural fascicles, homogeneous regeneration pattern, increased density and size of regenerative fibers, existence of epineural and perineural regeneration, uniform target orientation of regenerative fibers, and higher proportion of neural vs. connective tissue, all fascicles in each nerve showed increased diameter of myelinated fibers, thickness of myelin sheet, number of myelinated fibers per area and myelinated fibers as a percentage of the nerve transected area and the increased blood vessels presentation), electrophysiologically (increased motor action potentials), functionally (improved SFI), the autotomy absent. Thus, BPC 157 markedly improved rat sciatic nerve healing.

  3. Reversible reactivity by optic nerve astrocytes.

    PubMed

    Sun, Daniel; Qu, Juan; Jakobs, Tatjana C

    2013-08-01

    Reactive astrocytes are typically studied in models that cause irreversible mechanical damage to axons, neuronal cell bodies, and glia. Here, we evaluated the response of astrocytes in the optic nerve head to a subtle injury induced by a brief, mild elevation of the intraocular pressure. Astrocytes demonstrated reactive remodeling that peaked at three days, showing hypertrophy, process retraction, and simplification of their shape. This was not accompanied by any significant changes in the gene expression profile. At no time was there discernible damage to the optic axons, as evidenced by electron microscopy and normal anterograde and retrograde transport. Remarkably, the morphological remodeling was reversible. These findings underscore the plastic nature of reactivity. They show that reactivity can resolve fully if the insult is removed, and suggest that reactivity per se is not necessarily deleterious to axons. This reaction may represent very early events in the sequence that eventually leads to glial scarring.

  4. Optic nerve axons and acquired alterations in the appearance of the optic disc.

    PubMed Central

    Wirtschafter, J D

    1983-01-01

    The pathophysiologic events in optic nerve axons have recently been recognized as crucial to an understanding of clinically significant acquired alterations in the ophthalmoscopic appearance of the optic disc. Stasis and related abnormalities of axonal transport appear to explain most aspects of optic nerve head swelling, including optic disc drusen and retinal cottonwool spots. Loss of axoplasm and axonal death can be invoked to interpret optic disc pallor, thinning and narrowing of rim tissue, changes in the size and outline of the optic cup, laminar dots, atrophy of the retinal nerve fiber layer, and acquired demyelination and myelination of the retinal nerve fiber layer. It is speculated that the axons may also play a role in the mechanical support of the lamina cribrosa in resisting the pressure gradient across the pars scleralis of the optic nerve head. Axons and their associated glial cells may be involved in those cases where "reversibility" of cupping of the optic disc has been reported. The structure, physiology, and experimental pathologic findings of the optic nerve head have been reviewed. Many aspects concerning the final anatomic appearance of the optic nerve head have been explained. However, many questions remain concerning the intermediate mechanisms by which increased intracranial pressure retards the various components of axonal transport in papilledema and by which increased IOP causes axonal loss in glaucoma. Investigation of the molecular biology of axonal constituents and their responses to abnormalities in their physical and chemical milieu could extend our understanding of the events that result from mechanical compression and local ischemia. Moreover, we have identified a need to further explore the role of axons in the pathophysiology of optic disc cupping. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 11 FIGURE 12 FIGURE 13 PMID:6203209

  5. Nerve blocks for chronic pain.

    PubMed

    Hayek, Salim M; Shah, Atit

    2014-10-01

    Nerve blocks are often performed as therapeutic or palliative interventions for pain relief. However, they are often performed for diagnostic or prognostic purposes. When considering nerve blocks for chronic pain, clinicians must always consider the indications, risks, benefits, and proper technique. Nerve blocks encompass a wide variety of interventional procedures. The most common nerve blocks for chronic pain and that may be applicable to the neurosurgical patient population are reviewed in this article. This article is an introduction and brief synopsis of the different available blocks that can be offered to a patient.

  6. Nerves on magnetic resonance imaging.

    PubMed Central

    Collins, J. D.; Shaver, M. L.; Batra, P.; Brown, K.

    1989-01-01

    Nerves are often visualized on magnetic resonance imaging (MRI) studies of the soft tissues on the chest and shoulder girdle. To learn the reasons for the contrast between the nerves and adjacent tissues, the authors obtained a fresh specimen containing part of the brachial plexus nerves from the left axilla and compared MRI with x-ray projections and photomicrographs of histologic sections. The results suggest that the high signals from the nerves stand out in contrast to the low signals from their rich vascular supply. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6A Figure 6B Figure 7 PMID:2733051

  7. [Imaging anatomy of cranial nerves].

    PubMed

    Hermier, M; Leal, P R L; Salaris, S F; Froment, J-C; Sindou, M

    2009-04-01

    Knowledge of the anatomy of the cranial nerves is mandatory for optimal radiological exploration and interpretation of the images in normal and pathological conditions. CT is the method of choice for the study of the skull base and its foramina. MRI explores the cranial nerves and their vascular relationships precisely. Because of their small size, it is essential to obtain images with high spatial resolution. The MRI sequences optimize contrast between nerves and surrounding structures (cerebrospinal fluid, fat, bone structures and vessels). This chapter discusses the radiological anatomy of the cranial nerves.

  8. Accuracy of regenerating motor neurons: influence of diffusion in denervated nerve.

    PubMed

    Madison, R D; Robinson, G A

    2014-07-25

    Following injury to a peripheral nerve the denervated distal nerve segment undergoes remarkable changes including loss of the blood-nerve barrier, Schwann cell proliferation, macrophage invasion, and the production of many cytokines and neurotrophic factors. The aggregate consequence of such changes is that the denervated nerve becomes a permissive and even preferred target for regenerating axons from the proximal nerve segment. The possible role that an original end-organ target (e.g. muscle) may play in this phenomenon during the regeneration period is largely unexplored. We used the rat femoral nerve as an in vivo model to begin to address this question. We also examined the effects of disrupting communication with muscle in terms of accuracy of regenerating motor neurons as judged by their ability to correctly project to their original terminal nerve branch. Our results demonstrate that the accuracy of regenerating motor neurons is dependent upon the denervated nerve segment remaining in uninterrupted continuity with muscle. We hypothesized that this influence of muscle on the denervated nerve might be via diffusion-driven movement of biomolecules or the active axonal transport that continues in severed axons for several days in the rat, so we devised experiments to separate these two possibilities. Our data show that disrupting ongoing diffusion-driven movement in a denervated nerve significantly reduces the accuracy of regenerating motor neurons.

  9. The distribution of galanin-immunoreactive nerve fibers in the rat pharynx.

    PubMed

    Suzuki, Toshihiko; Sato, Tadasu; Kano, Mitsuhiro; Ichikawa, Hiroyuki

    2013-08-01

    Galanin (GAL) consists of a chain of 29/30 amino acids which is widely distributed in the central and peripheral nervous systems. In this study, the distribution of GAL-immunoreactive (-IR) nerve fibers was examined in the rat pharynx and its adjacent regions. GAL-IR nerve fibers were located beneath the epithelium and taste bud-like structure of the pharynx, epiglottis, soft palate and larynx. These nerve fibers were abundant in the laryngeal part of the pharynx, and were rare in other regions. Mucous glands were mostly devoid of GAL-IR nerve fibers. In the musculature of pharyngeal constrictor muscles, many GAL-IR nerve fibers were also located around small blood vessels. However, intrinsic laryngeal muscles contained only a few GAL-IR nerve fibers. The double immunofluorescence method demonstrated that the distribution pattern of GAL-IR nerve fibers was partly similar to that of calcitonin gene-related peptide-IR nerve fibers in the pharyngeal mucosa and muscles. The present findings suggest that the pharynx is one of main targets of GAL-containing nerves in the upper digestive and respiratory systems. These nerves may have sensory and autonomic origins.

  10. Sulodexide prevents peripheral nerve damage in streptozotocin induced diabetic rats.

    PubMed

    Jin, Heung Yong; Lee, Kyung Ae; Song, Sun Kyung; Liu, Wei Jing; Choi, Ji Hae; Song, Chang Ho; Baek, Hong Sun; Park, Tae Sun

    2012-01-15

    We investigated whether sulodexide has additional protective effects against peripheral nerve damage caused by microvascular dysfunction in a rat model of diabetes. Female Sprague-Dawley (SD) rats were divided into the following 4 groups (n=7-9/group): Normal, Normal+Sulodexide (sulodexide 10mg/kg), diabetic group, and diabetic+Sulodexide (sulodexide 10mg/kg). We assessed current perception threshold, skin blood flow, superoxide dismutase, and proteinuria in experimental rats after oral administration of sulodexide for 20 weeks. We also performed morphometric analysis of sciatic nerves and intraepidermal nerve fibers of the foot. Superoxide dismutase activity in the blood and sciatic nerve were increased significantly after sulodexide treatment in the diabetic group. Current perception threshold was reduced at 2000 Hz (633.3 ± 24.15 vs 741.2 ± 23.5 μA, P<0.05) and skin blood flow was improved (10.90 ± 0.67 vs 8.85 ± 0.49 TPU, P<0.05) in the diabetic+Sulodexide group compared with the diabetic group. The mean myelinated axon area was significantly larger (56.6 ± 2.2 vs 49.8 ± 2.7 μm(2), P<0.05) and the intraepidermal nerve fiber density was significantly less reduced (6.27 ± 0.24 vs 5.40 ± 0.25/mm, P<0.05) in the diabetic+Sulodexide group compared to the diabetic group. Our results demonstrate that sulodexide exhibits protective effects against peripheral nerve damage in a rat experimental model of diabetes. Therefore, these findings suggest that sulodexide is a potential new therapeutic agent for diabetic peripheral neuropathy.

  11. Accessory nerve palsy.

    PubMed

    Olarte, M; Adams, D

    1977-11-01

    After apparently uncomplicated excision of benign lesions in the posterior cervical triangle, two patients had shoulder pain. In one, neck pain and trapezius weakness were not prominent until one month after surgery. Inability to elevate the arm above the horizontal without externally rotating it, and prominent scapular displacement on arm abduction, but not on forward pushing movements, highlighted the trapezius dysfunction and differentiated it from serratus anterior weakness. Spinal accessory nerve lesions should be considered when minor surgical procedures, lymphadenitis, minor trauma, or tumours involved the posterior triangle of the neck.

  12. Update and critical appraisal of combined timolol and carbonic anhydrase inhibitors and the effect on ocular blood flow in glaucoma patients

    PubMed Central

    Moss, Adam M; Harris, Alon; Siesky, Brent; Rusia, Deepam; Williamson, Kathleen M; Shoshani, Yochai

    2010-01-01

    Topical hypotensive therapy with both timolol and carbonic anhydrase inhibitors has been shown to be efficacious at reducing intraocular pressure. Many prospective studies have also suggested that carbonic anhydrase inhibitors augment ocular blood flow and vascular regulation independent of their hypotensive effects. Although consistent in their findings, these studies must be cautiously interpreted due to the limitations of study design and specific blood flow imaging modalities. The purpose of this review is to appraise and critically evaluate the current body of literature investigating the effects of combined treatment with topical carbonic anhydrase inhibitors and timolol in patients with glaucoma with respect to ocular blood flow, visual function, and optic nerve head structure. PMID:20463789

  13. Disorders of the lower cranial nerves

    PubMed Central

    Finsterer, Josef; Grisold, Wolfgang

    2015-01-01

    Lesions of the lower cranial nerves (LCN) are due to numerous causes, which need to be differentiated to optimize management and outcome. This review aims at summarizing and discussing diseases affecting LCN. Review of publications dealing with disorders of the LCN in humans. Affection of multiple LCN is much more frequent than the affection of a single LCN. LCN may be affected solely or together with more proximal cranial nerves, with central nervous system disease, or with nonneurological disorders. LCN lesions have to be suspected if there are typical symptoms or signs attributable to a LCN. Causes of LCN lesions can be classified as genetic, vascular, traumatic, iatrogenic, infectious, immunologic, metabolic, nutritional, degenerative, or neoplastic. Treatment of LCN lesions depends on the underlying cause. An effective treatment is available in the majority of the cases, but a prerequisite for complete recovery is the prompt and correct diagnosis. LCN lesions need to be considered in case of disturbed speech, swallowing, coughing, deglutition, sensory functions, taste, or autonomic functions, neuralgic pain, dysphagia, head, pharyngeal, or neck pain, cardiac or gastrointestinal compromise, or weakness of the trapezius, sternocleidomastoid, or the tongue muscles. To correctly assess manifestations of LCN lesions, precise knowledge of the anatomy and physiology of the area is required. PMID:26167022

  14. Disorders of the lower cranial nerves.

    PubMed

    Finsterer, Josef; Grisold, Wolfgang

    2015-01-01

    Lesions of the lower cranial nerves (LCN) are due to numerous causes, which need to be differentiated to optimize management and outcome. This review aims at summarizing and discussing diseases affecting LCN. Review of publications dealing with disorders of the LCN in humans. Affection of multiple LCN is much more frequent than the affection of a single LCN. LCN may be affected solely or together with more proximal cranial nerves, with central nervous system disease, or with nonneurological disorders. LCN lesions have to be suspected if there are typical symptoms or signs attributable to a LCN. Causes of LCN lesions can be classified as genetic, vascular, traumatic, iatrogenic, infectious, immunologic, metabolic, nutritional, degenerative, or neoplastic. Treatment of LCN lesions depends on the underlying cause. An effective treatment is available in the majority of the cases, but a prerequisite for complete recovery is the prompt and correct diagnosis. LCN lesions need to be considered in case of disturbed speech, swallowing, coughing, deglutition, sensory functions, taste, or autonomic functions, neuralgic pain, dysphagia, head, pharyngeal, or neck pain, cardiac or gastrointestinal compromise, or weakness of the trapezius, sternocleidomastoid, or the tongue muscles. To correctly assess manifestations of LCN lesions, precise knowledge of the anatomy and physiology of the area is required.

  15. Phosphylated tyrosine in albumin as a biomarker of exposure to organophosphorus nerve agents.

    PubMed

    Williams, Nichola H; Harrison, John M; Read, Robert W; Black, Robin M

    2007-09-01

    The organophosphorus nerve agents sarin, soman, cyclosarin and tabun phosphylate a tyrosine residue on albumin in human blood. These adducts may offer relatively long-lived biological markers of nerve agent exposure that do not 'age' rapidly, and which are not degraded by therapy with oximes. Sensitive methods for the detection of these adducts have been developed using liquid chromatography-tandem mass spectrometry. Adducts of all four nerve agents were detected in the blood of exposed guinea pigs being used in studies to improve medical countermeasures. The tyrosine adducts with soman and tabun were detected in guinea pigs receiving therapy 7 days following subcutaneous administration of five times the LD(50) dose of the respective nerve agent. VX also forms a tyrosine adduct in human blood in vitro but only at high concentrations.

  16. A practical approach to optic nerve crush in the mouse

    PubMed Central

    Geisert, Eldon E.

    2012-01-01

    Our goal is to provide an instructional resource to help others wishing to use the optic nerve crush (ONC) as an experimental procedure. The process is described beginning with the anesthesia, followed by positioning of the mouse, the surgery itself, and post-surgical care. We analyzed the effect of ONC on retinal blood flow, using optical coherence tomography doppler. This procedure produces a consistent loss of cells in the ganglion cell layer, using whole mounts of retina stained with TO-PRO-3. An instructional video is presented that demonstrates a simple surgical approach to effectively crush the optic nerve of the mouse. PMID:22876142

  17. [Effect of Solcoseryl on nerve tissue under in vitro conditions].

    PubMed

    Lindner, G; Grosse, G; Plonka, G

    1976-01-01

    Explants from trigeminal ganglia and skin of chick embryos and hippocampus from fetal rats were cultivated in Maximow assembly in the presence of Solcoseryl (Solco AG, Basel), a blood extract of calf. Solcoseryl in vitro did not influence the regeneration of nerve fibers from CNS explants. A stimulatory effect of Solcoseryl in vitro by 1% concentration on the outgrowth of new processes in explants of PNS was demonstrated. It is discussed: under optimal concentration Solcoseryl may be important for the influence of the composition of the medium in which explants of the nerve system and skin are cultivated.

  18. Preservation of cranial nerves during removal of the brain for an enhanced student experience in neuroanatomy classes.

    PubMed

    Long, Jennifer; Roberts, David J H; Pickering, James D

    2014-01-01

    Neuroanatomy teaching at the University of Leeds includes the examination of isolated brains by students working in small groups. This requires the prosected brains to exhibit all 12 pairs of cranial nerves. Traditional methods of removing the brain from the skull involve elevating the frontal lobes and cutting each cranial nerve as the brain is reflected posteriorly. This can leave a substantial length of each nerve attached to the skull base rather than to the removed brain. We have found a posterior approach more successful. In this study, five adult heads were disarticulated at the level of the thyroid cartilage and placed, prone, in a head stand. A wedge of bone from the occipital region was removed before the cerebellum and brainstem were elevated to visualize the cranial nerves associated with the medulla oblongata, cerebellopontine angle and mesencephalic-pontine junction prior to cutting them as close to the skull as possible. Five brains were successfully removed from the skull, each having a full complement of cranial nerves of good length attached to them. This approach significantly increases the length and number of cranial nerves remaining attached to the brain, which supports student education. For integration into head and neck dissection courses, careful consideration will be required to ensure the necks are suitably dissected and to decide whether the cranial nerves are best left attached to the skull base or brain.

  19. The Multiple Silicone Tube Device, “Tubes within a Tube,” for Multiplication in Nerve Reconstruction

    PubMed Central

    Dahlin, Lars B.

    2014-01-01

    Multiple nerve branches were created during the regeneration procedure after a nerve injury and such multiple branches are suggested to be used to control, for example, prosthesis with many degrees of freedom. Transected rat sciatic nerve stumps were inserted into a nine mm long silicone tube, which contained four, five mm long, smaller tubes, thus leaving a five mm gap for regenerating nerve fibers. Six weeks later, several new nerve structures were formed not only in the four smaller tubes, but also in the spaces in-between. The 7–9 new continuous nerve structures, which were isolated as individual free nerves after removal of the tubes, were delineated by a perineurium and contained both myelinated and unmyelinated nerve fibers as well as blood vessels. Stimulation of the proximal nerve elicited contractions in distal muscles. Thin metal electrodes, inserted initially into the smaller tubes in some experiments, became embedded in the new nerve structures and when stimulated contractions of the distal muscles were observed. The “tubes within a tube” technique, creating multiple new nerves from a single “mother” nerve, can be used to record multiple signals for prosthetic device control or as sources for supply of multiple denervated targets. PMID:24864255

  20. Facial nerve palsy due to birth trauma

    MedlinePlus

    Seventh cranial nerve palsy due to birth trauma; Facial palsy - birth trauma; Facial palsy - neonate; Facial palsy - infant ... infant's facial nerve is also called the seventh cranial nerve. It can be damaged just before or at ...

  1. Functions of the Renal Nerves.

    ERIC Educational Resources Information Center

    Koepke, John P.; DiBona, Gerald F.

    1985-01-01

    Discusses renal neuroanatomy, renal vasculature, renal tubules, renin secretion, renorenal reflexes, and hypertension as related to renal nerve functions. Indicates that high intensitites of renal nerve stimulation have produced alterations in several renal functions. (A chart with various stimulations and resultant renal functions and 10-item,…

  2. Neuromas of the calcaneal nerves.

    PubMed

    Kim, J; Dellon, A L

    2001-11-01

    A neuroma of a calcaneal nerve has never been reported. A series of 15 patients with heel pain due to a neuroma of a calcaneal nerve are reviewed. These patients previously had either a plantar fasciotomy (n = 4), calcaneal spur removal (n = 2), ankle fusion (n = 2), or tarsal tunnel decompression (n = 7). Neuromas occurred on calcaneal branches that arose from either the posterior tibial nerve (n = 1), lateral plantar nerve (n = 1), the medial plantar nerve (n = 9), or more than one of these nerves (n = 4). Operative approach was through an extended tarsal tunnel incision to permit identification of all calcaneal nerves. The neuroma was resected and implanted into the flexor hallucis longus muscle. Excellent relief of pain occurred in 60%, and good relief in 33%. One patient (17%) had no improvement and required resection of the lateral plantar nerve. Awareness that the heel may be innervated by multiple calcaneal branches suggests that surgery for heel pain of neural origin employ a surgical approach that permits identification of all possible calcaneal branches.

  3. Optic nerve atrophy

    MedlinePlus

    Optic atrophy; Optic neuropathy ... There are many causes of optic atrophy. The most common is poor blood flow. This is called ischemic optic neuropathy. The problem most often affects older adults. ...

  4. Distal median nerve dysfunction

    MedlinePlus

    ... hormone in the body ( acromegaly ) Diabetes Underactive thyroid ( hypothyroidism ) Kidney disease Blood cancer called multiple myeloma Pregnancy ... Read More Acromegaly Arthritis Carpal tunnel ... mononeuropathy Multiple myeloma Peripheral Peripheral neuropathy ...

  5. Bottom head assembly

    DOEpatents

    Fife, A.B.

    1998-09-01

    A bottom head dome assembly is described which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome. The bottom head dome has a plurality of openings extending there through. The liner also has a plurality of openings extending there through, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending there through, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore there through, and each support stub bore aligns with a respective bottom head dome opening. 2 figs.

  6. Bottom head assembly

    DOEpatents

    Fife, Alex Blair

    1998-01-01

    A bottom head dome assembly which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome is described. The bottom head dome has a plurality of openings extending therethrough. The liner also has a plurality of openings extending therethrough, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending therethrough, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore therethrough, and each support stub bore aligns with a respective bottom head dome opening.

  7. Deposition head for laser

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    1999-01-01

    A deposition head for use as a part of apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. The deposition head delivers the laser beam and powder to a deposition zone, which is formed at the tip of the deposition head. A controller comprised of a digital computer directs movement of the deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which the deposition head moves along the tool path.

  8. Peripheral nerve conduits: technology update

    PubMed Central

    Arslantunali, D; Dursun, T; Yucel, D; Hasirci, N; Hasirci, V

    2014-01-01

    Peripheral nerve injury is a worldwide clinical problem which could lead to loss of neuronal communication along sensory and motor nerves between the central nervous system (CNS) and the peripheral organs and impairs the quality of life of a patient. The primary requirement for the treatment of complete lesions is a tension-free, end-to-end repair. When end-to-end repair is not possible, peripheral nerve grafts or nerve conduits are used. The limited availability of autografts, and drawbacks of the allografts and xenografts like immunological reactions, forced the researchers to investigate and develop alternative approaches, mainly nerve conduits. In this review, recent information on the various types of conduit materials (made of biological and synthetic polymers) and designs (tubular, fibrous, and matrix type) are being presented. PMID:25489251

  9. "Dropped head syndrome" caused by Lambert-Eaton myasthenic syndrome.

    PubMed

    Ueda, T; Kanda, F; Kobessho, H; Hamaguchi, H; Motomura, M

    2009-07-01

    A 67-year-old man was admitted with a 2-year history of dropped head. Neurological examination revealed ptosis, dysarthria, neck weakness, hyporeflexia of all limbs, and autonomic failure. Electrophysiologic study showed a 400% increment response to high-rate repetitive nerve stimulation. Serum anti-P/Q-voltage-gated calcium channel antibody was positive, confirming the diagnosis of Lambert-Eaton myasthenic syndrome (LEMS). His symptoms and electrophysiological abnormalities improved with oral prednisolone following plasmapheresis. This is the first report of LEMS as a cause of dropped head syndrome.

  10. Optic Nerve Decompression through a Supraorbital Approach

    PubMed Central

    Rigante, Luigi; Evins, Alexander I.; Berra, Luigi V.; Beer-Furlan, André; Stieg, Philip E.; Bernardo, Antonio

    2015-01-01

    Objective We propose a stepwise decompression of the optic nerve (ON) through a supraorbital minicraniotomy and describe the surgical anatomy of the ON as seen through this approach. We also discuss the clinical applications of this approach. Methods Supraorbital approaches were performed on 10 preserved cadaveric heads (20 sides). First, 3.5-cm skin incisions were made along the supraciliary arch from the medial third of the orbit and extended laterally. A 2 × 3-cm bone flap was fashioned and extradural dissections were completed. A 180-degree unroofing of the ON was achieved, and the length and width of the proximal and distal portions of the optic canal (OC) were measured. Results The supraorbital minicraniotomy allowed for identification of the anterior clinoid process and other surgical landmarks and adequate drilling of the roof of the OC with a comfortable working angle. A 25-degree contralateral head rotation facilitated visualization of the ON. Conclusion The supraorbital approach is a minimally invasive and cosmetically favorable alternative to more extended approaches with longer operative times used for the management of ON decompression in posttraumatic or compressive optic neuropathy from skull base pathologies extending into the OC. The relative ease of this approach provides a relatively short learning curve for developing neurosurgeons. PMID:26225308

  11. Head and neck paragangliomas: clinical and molecular genetic classification

    PubMed Central

    Offergeld, Christian; Brase, Christoph; Yaremchuk, Svetlana; Mader, Irina; Rischke, Hans Christian; Gläsker, Sven; Schmid, Kurt W; Wiech, Thorsten; Preuss, Simon F; Suárez, Carlos; Kopeć, Tomasz; Patocs, Attila; Wohllk, Nelson; Malekpour, Mahdi; Boedeker, Carsten C; Neumann, Hartmut PH

    2012-01-01

    Head and neck paragangliomas are tumors arising from specialized neural crest cells. Prominent locations are the carotid body along with the vagal, jugular, and tympanic glomus. Head and neck paragangliomas are slowly growing tumors, with some carotid body tumors being reported to exist for many years as a painless lateral mass on the neck. Symptoms depend on the specific locations. In contrast to paraganglial tumors of the adrenals, abdomen and thorax, head and neck paragangliomas seldom release catecholamines and are hence rarely vasoactive. Petrous bone, jugular, and tympanic head and neck paragangliomas may cause hearing loss. The internationally accepted clinical classifications for carotid body tumors are based on the Shamblin Class I–III stages, which correspond to postoperative permanent side effects. For petrous-bone paragangliomas in the head and neck, the Fisch classification is used. Regarding the molecular genetics, head and neck paragangliomas have been associated with nine susceptibility genes: NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, SDHAF2 (SDH5), and TMEM127. Hereditary HNPs are mostly caused by mutations of the SDHD gene, but SDHB and SDHC mutations are not uncommon in such patients. Head and neck paragangliomas are rarely associated with mutations of VHL, RET, or NF1. The research on SDHA, SDHAF2 and TMEM127 is ongoing. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. The treatment of choice is surgical resection. Good postoperative results can be expected in carotid body tumors of Shamblin Class I and II, whereas operations on other carotid body tumors and other head and neck paragangliomas frequently result in deficits of the cranial nerves adjacent to the tumors. Slow growth and the tendency of hereditary head and neck paragangliomas to be multifocal may justify less aggressive treatment strategies. PMID:22584701

  12. Nerve glue for upper extremity reconstruction.

    PubMed

    Tse, Raymond; Ko, Jason H

    2012-11-01

    Nerve glue is an attractive alternative to sutures to improve the results of nerve repair. Improved axon alignment, reduced scar and inflammation, greater and faster reinnervation, and better functional results have been reported with the use of nerve glue. The different types of nerve glue and the evidence to support or oppose their use are reviewed. Although the ideal nerve glue has yet to be developed, fibrin sealants can be used as nerve glue in select clinical situations. Technology to allow suture-free nerve repair is one development that can potentially improve functional nerve recovery and the outcomes of upper extremity reconstruction.

  13. Facial nerve rerouting in skull base surgery.

    PubMed

    Parhizkar, Nooshin; Hiltzik, David H; Selesnick, Samuel H

    2005-08-01

    Facial nerve rerouting techniques were developed to facilitate re-section of extensive tumors occupying the skull base. Facial nerve rerouting has its own limitations and risks, requiring microsurgical expertise, additional surgical time, and often some degree of facial nerve paresis. This article presents different degrees of anterior and posterior facial nerve rerouting, techniques of facial nerve rerouting, and a comprehensive review of outcomes. It then reviews anatomic and functional preservation of the facial nerve in acoustic neuroma resection, technical aspects of facial nerve dissection, intracranial facial nerve repair options, and outcomes for successful acoustic neuroma surgery.

  14. Maternal nerve growth factor levels during pregnancy in women with preeclampsia: A longitudinal study.

    PubMed

    D'souza, Vandita; Kilari, Anitha; Pisal, Hemlata; Patil, Vidya; Mehendale, Savita; Wagh, Girija; Gupte, Sanjay; Joshi, Sadhana

    2015-12-01

    Preeclampsia (PE) is characterized by hypertension and proteinuria. Improper development of the placenta due to altered angiogenesis is the main culprit in PE. Nerve growth factor (NGF) is an angiogenic factor which is expressed and localized in the placenta. Our earlier cross sectional study has shown altered NGF levels at delivery in women with PE. However, there are no studies on NGF levels in PE early in pregnancy before manifestation of the disease. Thus, there is a need to examine the role of NGF in vascular development during different stages of gestation in PE. A longitudinal study was carried out where pregnant women were enrolled from two major hospitals from Pune, Bharati hospital and Gupte hospital. They were followed at three different time points [16-20 weeks (T1), 26-30 weeks (T2) and at delivery (T3)] during pregnancy and maternal blood at every time point and cord blood at delivery was collected and processed. This study included normotensive women (n=88) and women with PE (n=48). NGF levels were measured from maternal and cord plasma using the Emax Immuno Assay System (Promega). The data was analyzed using the SPSS/PC+ package (Version 20.0, Chicago, IL, USA). Maternal NGF levels did not change at all time points while cord NGF levels were higher (p<0.05) in women with PE. Further, maternal NGF levels were negatively associated with blood pressure while cord NGF levels were positively associated with baby head circumference. Our data suggests that there may possibly be a compensatory role for NGF in the foeto-placental circulation in PE.

  15. Isolated oculomotor nerve palsy resulting from acute traumatic tentorial subdural hematoma

    PubMed Central

    Cui, Victoria; Kouliev, Timur

    2016-01-01

    Acute subdural hematoma (SDH) resulting from head trauma is a potentially life-threatening condition that requires expedient diagnosis and intervention to ensure optimal patient outcomes. Rapidly expanding or large hematomas, elevated intracranial pressure, and associated complications of brain herniation are associated with high mortality rates and poor recovery of neurological function. However, smaller bleeds (clot thickness <10 mm) or hematomas occurring in infrequent locations, such as the tentorium cerebelli, may be difficult to recognize and patients may present with unusual or subtle signs and symptoms, including isolated cranial nerve palsies. Knowledge of neuroanatomy supported by modern neuroimaging can greatly aid in recognition and diagnosis of such lesions. In this report, we present a case of isolated oculomotor nerve palsy resulting from compressive tentorial SDH following blunt head trauma, review the literature concerning similar cases, and make recommendations regarding the diagnosis of SDH in patients presenting with isolated cranial nerve palsies. PMID:27843362

  16. Fluorescent nanoparticles for observing primo vascular system along sciatic nerve.

    PubMed

    Jia, Zhao-Feng; Lee, Byung-Cheon; Eom, Ki-Hoon; Cha, Jin-Myung; Lee, Jin-Kyu; Su, Zhen-Dong; Yu, Wen-Hui; Ryu, Pan Dong; Soh, Kwang-Sup

    2010-09-01

    The primo vascular system was found in the epineurium along the rat sciatic nerve following subcutaneous injection of fluorescent nanoparticles at the Zusanli acupoint (ST-36). Nanoparticles were injected into the primo-vessel near ST-36 and flowed along the sciatic nerve. Fluorescence revealed a structure in the epineurium that was hardly detectable. Images of the isolated sample stained with 4',6-diamidino-2-phenylindole were captured using confocal microscopy. These images showed the distinctive nuclei distribution and multi-lumen structure of primo-vessels that differentiate them from lymphatic vessels, blood capillaries and nerves. This study demonstrates a new use for nanoparticles in fluorescence reflectance imaging techniques during in vivo imaging of primo-vessels.

  17. Blood pressure

    MedlinePlus Videos and Cool Tools

    Normal blood pressure is important for proper blood flow to the body's organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart ...

  18. Lumbosacral nerve root avulsion.

    PubMed

    Chin, C H; Chew, K C

    1997-01-01

    Lumbosacral nerve root avulsion is a rare clinical entity. Since the first description in 1955, only 35 cases have been reported. It is often associated with pelvic fractures and may be missed in the initial clinical examination as these patients usually present with multiple injuries. We present three such cases with clinical and radiological findings. These patients were involved in road traffic accidents. Two had fractures of the sacroiliac joint with diastasis of the symphysis pubis (Tile type C 1.2) and one had fractures of the public rami (Tile type B 2.1). All three had various degrees of sensory and motor deficit of the lower limbs. Lumbar myelogram shows characteristic pseudomeningoceles in the affected lumboscral region. Magnetic resonance (MR) imaging provides an additional non-invasive modality to diagnose this condition.

  19. Optic Nerve Sheath Meningiomas.

    PubMed

    Radhakrishnan, Sunita; Lee, Michael S

    2005-01-01

    Optic nerve sheath meningiomas (ONSMs) grow slowly and, if untreated, patients may have stable visual function for up to several years. Treatment of an ONSM may lead to vision loss (radiation retinopathy or optic neuropathy). Therefore, observation is recommended for a patient with ONSM and relatively preserved visual acuity, color vision, pupils, and visual fields. Follow-up every 4 to 6 months initially is recommended extending to annual examinations if visual function and tumor size remain stable for a few years. Neuroimaging can be repeated every 12 months. An undisputed decline in visual function or any intracranial extension warrants treatment of the ONSM. The treatment of choice for a tumor confined to the orbit is stereotactic fractionated radiation. Stereotactic fractionated radiation uses multiple small doses of radiation using tight margins. A reasonable alternative, three-dimensional conformal fractionated radiation uses computed tomography-guided planning but usually requires wider margins. Conventional radiation uses much wider margins and would not be recommended for treatment of ONSM. The radiation can be administered during 5 to 6 weeks in 28 daily fractions of 1.8 to 2 Gy/fraction to a total of 50.4 to 56 Gy. Many patients have improvement or stabilization of their visual function. Gamma knife radiosurgery does not have a role in ONSM because the required dose is toxic to the optic nerve. A tumor that extends intracranially may be treated with fractionated radiation if any vision remains. Surgical excision can be considered for significant intracranial extension but this often leads to complete vision loss in the ipsilateral eye. A blind, disfigured eye also may be treated with en bloc surgical resection of the meningioma.

  20. Adipose-derived stem cells stimulate regeneration of peripheral nerves: BDNF secreted by these cells promotes nerve healing and axon growth de novo.

    PubMed

    Lopatina, Tatiana; Kalinina, Natalia; Karagyaur, Maxim; Stambolsky, Dmitry; Rubina, Kseniya; Revischin, Alexander; Pavlova, Galina; Parfyonova, Yelena; Tkachuk, Vsevolod

    2011-03-14

    Transplantation of adipose-derived mesenchymal stem cells (ASCs) induces tissue regeneration by accelerating the growth of blood vessels and nerve. However, mechanisms by which they accelerate the growth of nerve fibers are only partially understood. We used transplantation of ASCs with subcutaneous matrigel implants (well-known in vivo model of angiogenesis) and model of mice limb reinnervation to check the influence of ASC on nerve growth. Here we show that ASCs stimulate the regeneration of nerves in innervated mice's limbs and induce axon growth in subcutaneous matrigel implants. To investigate the mechanism of this action we analyzed different properties of these cells and showed that they express numerous genes of neurotrophins and extracellular matrix proteins required for the nerve growth and myelination. Induction of neural differentiation of ASCs enhances production of brain-derived neurotrophic factor (BDNF) as well as ability of these cells to induce nerve fiber growth. BDNF neutralizing antibodies abrogated the stimulatory effects of ASCs on the growth of nerve sprouts. These data suggest that ASCs induce nerve repair and growth via BDNF production. This stimulatory effect can be further enhanced by culturing the cells in neural differentiation medium prior to transplantation.

  1. Glucagon Release Induced by Pancreatic Nerve Stimulation in the Dog

    PubMed Central

    Marliss, Errol B.; Girardier, Lucien; Seydoux, Josiane; Wollheim, Claes B.; Kanazawa, Yasunori; Orci, Lelio; Renold, Albert E.; Porte, Daniel

    1973-01-01

    A direct neural role in the regulation of immunoreactive glucagon (IRG) secretion has been investigated during stimulation of mixed autonomic nerves to the pancreas in anesthetized dogs. The responses were evaluated by measurement of blood flow and hormone concentration in the venous effluent from the stimulated region of pancreas. Electrical stimulation of the distal end of the discrete bundles of nerve fibers isolated along the superior pancreaticoduodenal artery was invariably followed by an increase in IRG output. With 10-min periods of nerve stimulation, the integrated response showed that the higher the control glucagon output, the greater was the increment. Atropinization did not influence the response to stimulation. That the preparation behaved in physiologic fashion was confirmed by a fall in IRG output, and a rise in immunoreactive insulin (IRI) output, during hyperglycemia induced by intravenous glucose (0.1 g/kg). The kinetics of this glucose effect on IRG showed characteristics opposite to those of nerve stimulation: the lower the control output, the less the decrement. Furthermore, during the control steady state, blood glucose concentration was tightly correlated with the IRI/IRG molar output ratio, the function relating the two parameters being markedly nonlinear. Injection or primed infusion of glucose diminished the IRG response to simultaneous nerve stimulation. Measurement of IRG was inferred to reflect response of pancreatic glucagon secretion on the basis of the site of sample collection (the superior pancreaticoduodenal vein), the absence of changes in arterial IRG, and similar responses being obtained using an antibody specific for pancreatic glucagon. These studies support a role for the autonomic nervous system in the control of glucagon secretion: direct nerve stimulation induces glucagon release. Such sympathetic activation may be interpreted as capable of shifting the sensitivity of the A cell to glucose in the direction of higher

  2. [Post-traumatic infraorbital nerve neuropathy].

    PubMed

    Sakavicius, Dalius; Kubilius, Ricardas; Sabalys, Gintautas

    2002-01-01

    The authors have investigated functional state of infraorbital nerve of 479 patients with zygomatic fractures. The degree of nerve damage was evaluated according to changes of pain threshold during damaged nerve stimulation. It was estimated that in 64.3% of zygomatic fractures the infraorbital nerve was affected. The nerve damage degree could be mild, moderate and severe. In 43.18% of moderate and severe nerve damage cases the neuropathy develops. The symptoms, signs and treatment of neuropathy have been described. The neuropathy with clinical symptoms as permanent soreness and paresthesias (itch, "running ant", fibrillations of cheek tissues etc.) in the infraorbital nerve innervation zone occur to 43.18% of the patients after moderate and severe damage of the nerve. The treatment of neuropathy was analysed. In cases of moderate and severe nerve damages, authors recommend to perform decompression of the nerve, because if not applied, the function of nerve does not recover.

  3. Head Start. Fact Sheet.

    ERIC Educational Resources Information Center

    Administration for Children, Youth, and Families (DHHS), Washington, DC.

    Head Start is a national program that provides comprehensive developmental services for preschool children (ages 3 to 5) from low-income families and social services for their families. Approximately 1,400 community-based nonprofit organizations and school systems develop programs to meet specific needs. Head Start began in 1965 in the Office of…

  4. Woodpeckers and head injury.

    PubMed

    May, P R; Fuster, J M; Newman, P; Hirschman, A

    1976-02-28

    The woodpecker is an experiment in Nature, a model for the investigation of mechanisms of basic importance for head injury and its prevention. A preliminary anatomical study of the woodpecker's head suggests that it may be fruitful to explore impact protective systems which are radically different from those in common use.

  5. Hemodynamic Responses to Head and Neck Cooling

    NASA Technical Reports Server (NTRS)

    Ku, Yu-Tsuan E.; Carbo, Jorge E.; Montgomery, Leslie D.; Webbon, Bruce W.

    1994-01-01

    Personal thermoregulatory systems which provide head and neck cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objective of this study was to measure the scalp temperature and circulatory responses during use of one commercially available thermal control system. The Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used in this study. Two EEG electrodes and one skin temperature transducer were placed on the anterior midline of the scalp to measure the scalp blood and temperature. Blood flow was measured using a bipolar impedance rheograph. Ten subjects, seated in an upright position at normal room temperature, were tested at high, medium, moderate, moderate-low and low coolant temperatures. Scalp blood flow was recorded continuously using a computer data acquisition system with a sampling frequency of 200 Hz. Scalp temperature and cooling helmet Inlet temperature was logged periodically during the test period. This study quantifies the effect of head cooling upon scalp temperature and blood flow. These data may also be used to select operational specifications of the head cooling system for biomedical applications such as the treatment of migraine headaches, scalp cooling during chemotherapy, and cooling of multiple sclerosis patients.

  6. Electrostimulation and morphologic study of the nerves to the bone marrow of the albino rat.

    PubMed

    DePace, D M; Webber, R H

    1975-01-01

    The innervation of the bone marrow of the albino rat was investigated by electrostimulation and morphological methods. Stimulation of the lumbar sympathetic trunks resulted in the release of reticulocytes and neutrophils into the circulating blood. The effects of stimulation on other cell types in the bone marrow could not be definitely established. It was concluded that the nerve fibers to the bone marrow were distributed to the arteries. It is postulated that the transmitter substance released at the autonomic nerve endings may have an effect upon the permeability of the venous sinusiods and the mobility of the blood cells in the marrow parenchyma resulting in their release into the circulating blood.

  7. Iatrogenic selective lesion of the median nerve at the elbow.

    PubMed

    Di Fabio, Roberto; Casali, Carlo; Pierelli, Francesco

    2010-03-01

    A lesion of the median nerve may occur as a consequence of a compression by a haematoma or for a direct damage of the axons caused by a needle insertion. To date, no investigation reported a very selective lesion of the median nerve at the elbow, with the suffering limited only to the fibres for the first digit. A 53 year-old left-handed violinist underwent an arterial blood gas drawing. The patient complained immediately of an electrical shock impression going down the arm, followed by pin sensation into the first finger. A tingling sensation associated with numbness in the first fingertip and difficulty in the index-thumb pinch became progressively evident. The ENG-EMG findings showed an impairment mainly of the sensory fibres innervating the first digit and a drop of the motor action potential amplitude when the nerve was stimulated at the elbow. We reported a very partial lesion of the left median nerve at the elbow in a violinist who had a selective involvement of the fibres for his first digit. Even minimal lesions of the median nerve may impair severely the quality of life of patients.

  8. Biofabrication and testing of a fully cellular nerve graft.

    PubMed

    Owens, Christopher M; Marga, Francoise; Forgacs, Gabor; Heesch, Cheryl M

    2013-12-01

    Rupture of a nerve is a debilitating injury with devastating consequences for the individual's quality of life. The gold standard of repair is the use of an autologous graft to bridge the severed nerve ends. Such repair however involves risks due to secondary surgery at the donor site and may result in morbidity and infection. Thus the clinical approach to repair often involves non-cellular solutions, grafts composed of synthetic or natural materials. Here we report on a novel approach to biofabricate fully biological grafts composed exclusively of cells and cell secreted material. To reproducibly and reliably build such grafts of composite geometry we use bioprinting. We test our grafts in a rat sciatic nerve injury model for both motor and sensory function. In particular we compare the regenerative capacity of the biofabricated grafts with that of autologous grafts and grafts made of hollow collagen tubes by measuring the compound action potential (for motor function) and the change in mean arterial blood pressure as consequence of electrically eliciting the somatic pressor reflex. Our results provide evidence that bioprinting is a promising approach to nerve graft fabrication and as a consequence to nerve regeneration.

  9. Vagus nerve pain referred to the craniofacial region. A case report and literature review with implications for referred cardiac pain.

    PubMed

    Myers, D E

    2008-02-23

    The pain of angina pectoris and myocardial infarction is sometimes referred to the head and neck region. The mechanism for this effect remains obscure. A case is presented here that reports that electrical stimulation of a cardiac branch of the left vagus nerve in humans can cause referred craniofacial pain. This leads to the hypothesis that the vagus nerve plays a role in mediating this pain. A review of the clinical and physiologic literature supports this hypothesis.

  10. Controversies related to electromagnetic field exposure on peripheral nerves.

    PubMed

    Say, Ferhat; Altunkaynak, Berrin Zuhal; Coşkun, Sina; Deniz, Ömür Gülsüm; Yıldız, Çağrı; Altun, Gamze; Kaplan, Arife Ahsen; Kaya, Sefa Ersan; Pişkin, Ahmet

    2016-09-01

    Electromagnetic field (EMF) is a pervasive environmental presence in modern society. In recent years, mobile phone usage has increased rapidly throughout the world. As mobile phones are generally held close to the head while talking, studies have mostly focused on the central and peripheral nervous system. There is a need for further research to ascertain the real effect of EMF exposure on the nervous system. Several studies have clearly demonstrated that EMF emitted by cell phones could affect the systems of the body as well as functions. However, the adverse effects of EMF emitted by mobile phones on the peripheral nerves are still controversial. Therefore, this review summarizes current knowledge on the possible positive or negative effects of electromagnetic field on peripheral nerves.

  11. Cannieu-Riche anastomosis of the ulnar to median nerve in the hand: case report.

    PubMed

    Paraskevas, G; Ioannidis, O; Martoglou, S

    2010-01-01

    We observed in a male cadaver the presence of a new type of very long Cannieu-Riche anastomosis between the proximal portion of the deep branch of the ulnar nerve for the adductor pollicis and ramus of the recurrent branch of the median nerve to the superficial head of the flexor pollicis brevis. The clinical relevance of such a communication is the possible preservation of the function of all or part of thenar muscles from the ulnar nerve in case of median nerve lesion. The ignorance of that anomaly can induce obscure clinical, surgical and electroneuromyographical findings. We report on the incidence, the double innervation and the clinical significance of Cannieu-Riche anastomosis and provide a new classification of the various types of this nerval connection.

  12. In Vivo MR Microneurography of the Tibial and Common Peroneal Nerves

    PubMed Central

    Felisaz, Paolo F.; Chang, Eric Y.; Montagna, Stefano; Baldi, Maurizia

    2014-01-01

    MR microneurography is a noninvasive technique that provides visualization of the microanatomy of peripheral nerves, otherwise available only with histopathology. The objective of this study was to present a protocol to visualize the microstructure of peripheral nerves in vivo, using a 3T MRI scanner with a clinical set of coils and sequences. The tibial and the common peroneal nerves of healthy volunteers were imaged above the medial malleolus and at the level of the fibular head, respectively. The acquired images provided details about the internal structure of peripheral nerves, with visualization of the fascicles, the interfascicular fat, the epineurium, and the perineurium. MR microneurography can be performed in a clinical setting with acceptable imaging times and can be a potentially powerful tool that complements standard MR neurography. PMID:25548670

  13. Issues in the Optimal Selection of a Cranial Nerve Monitoring System

    PubMed Central

    Selesnick, Samuel H.; Goldsmith, Daniel F.

    1993-01-01

    Intraoperative nerve monitoring (IONM) is a safe technique that is of clear clinical value in the preservation of cranial nerves in skull base surgery and is rapidly becoming the standard of care. Available nerve monitoring systems vary widely in capabilities and costs. A well-informed surgeon may best decide on monitoring needs based on surgical case selection, experience, operating room space, availability of monitoring personnel, and cost. Key system characteristics that should be reviewed in the decision-making process include the monitoring technique (electromyography, pressure transducer, direct nerve monitoring, brainstem auditory evoked potential) and the stimulus technique (stimulating parameters, probe selection). In the past, IONM has been primarily employed in posterior fossa and temporal bone surgery, but the value of IONM is being recognized in more skull base and head and neck surgeries. Suggested IONM strategies for specific surgeries are presented. PMID:17170916

  14. In Vivo MR Microneurography of the Tibial and Common Peroneal Nerves.

    PubMed

    Felisaz, Paolo F; Chang, Eric Y; Carne, Irene; Montagna, Stefano; Balducci, Francesco; Maugeri, Giulia; Pichiecchio, Anna; Calliada, Fabrizio; Baldi, Maurizia; Bastianello, Stefano

    2014-01-01

    MR microneurography is a noninvasive technique that provides visualization of the microanatomy of peripheral nerves, otherwise available only with histopathology. The objective of this study was to present a protocol to visualize the microstructure of peripheral nerves in vivo, using a 3T MRI scanner with a clinical set of coils and sequences. The tibial and the common peroneal nerves of healthy volunteers were imaged above the medial malleolus and at the level of the fibular head, respectively. The acquired images provided details about the internal structure of peripheral nerves, with visualization of the fascicles, the interfascicular fat, the epineurium, and the perineurium. MR microneurography can be performed in a clinical setting with acceptable imaging times and can be a potentially powerful tool that complements standard MR neurography.

  15. Nanofibrous nerve conduit-enhanced peripheral nerve regeneration.

    PubMed

    Jiang, Xu; Mi, Ruifa; Hoke, Ahmet; Chew, Sing Yian

    2014-05-01

    Fibre structures represent a potential class of materials for the formation of synthetic nerve conduits due to their biomimicking architecture. Although the advantages of fibres in enhancing nerve regeneration have been demonstrated, in vivo evaluation of fibre size effect on nerve regeneration remains limited. In this study, we analyzed the effects of fibre diameter of electrospun conduits on peripheral nerve regeneration across a 15-mm critical defect gap in a rat sciatic nerve injury model. By using an electrospinning technique, fibrous conduits comprised of aligned electrospun poly (ε-caprolactone) (PCL) microfibers (981 ± 83 nm, Microfiber) or nanofibers (251 ± 32 nm, Nanofiber) were obtained. At three months post implantation, axons regenerated across the defect gap in all animals that received fibrous conduits. In contrast, complete nerve regeneration was not observed in the control group that received empty, non-porous PCL film conduits (Film). Nanofiber conduits resulted in significantly higher total number of myelinated axons and thicker myelin sheaths compared to Microfiber and Film conduits. Retrograde labeling revealed a significant increase in number of regenerated dorsal root ganglion sensory neurons in the presence of Nanofiber conduits (1.93 ± 0.71 × 10(3) vs. 0.98 ± 0.30 × 10(3) in Microfiber, p < 0.01). In addition, the compound muscle action potential (CMAP) amplitudes were higher and distal motor latency values were lower in the Nanofiber conduit group compared to the Microfiber group. This study demonstrated the impact of fibre size on peripheral nerve regeneration. These results could provide useful insights for future nerve guide designs.

  16. Solitary fibrous tumour of the vagus nerve.