Search results for "Nerve fibre"
showing 8 items of 8 documents
Bright Retinal Lesions Detection using Color Fundus Images Containing Reflective Features
2009
Recently, the research community has developed many techniques to detect and diagnose diabetic retinopathy with retinal fundus images. This is a necessary step for the implementation of a large scale screening effort in rural areas where ophthalmologists are not available. In the United States of America, the incidence of diabetes is increasing among the young population. Retina fundus images of patients younger than 20 years old present a high amount of reflectance due to the Nerve Fibre Layer (NFL). Generally, the younger the patient the more the reflectance is visible. We are not aware of algorithms able to explicitly deal with this type of artifact.
Association of ocular, cardiovascular, morphometric and lifestyle parameters with retinal nerve fibre layer thickness.
2017
BACKGROUND Glaucoma is a neurodegenerative disease, leading to thinning of the retinal nerve fibre layer (RNFL). The exact influence of ocular, cardiovascular, morphometric, lifestyle and cognitive factors on RNFL thickness (RNFLT) is unknown and was analysed in a subgroup of the Gutenberg Health Study (GHS). METHODS Global peripapillary RNFLT was measured in 3224 eyes of 1973 subjects (49% female) using spectral-domain optical coherence tomography (SD-OCT). The association of age, sex, ocular, cardiovascular, morphometric, lifestyle and cognitive factors on RNFLT was analysed using Pearson correlation coefficient and fitting a linear mixed model. RESULTS In the univariable analysis highest…
Retinal nerve fibre layer and brain grey substance as early prognostic factors for disability in multiple sclerosis.
2012
We read with interest the article by Bock et al ,1 in which the association between retinal nerve fibre layer (RNFL) and total macular volume (TMV) was analysed by optical coherence tomography (OCT) and contrast sensitivity was measured by functional acuity contrast testing in relapsing-remitting multiple sclerosis (MS) patients. The authors found that the functional contrast vision in MS is influenced by morphological changes in the anterior visual pathway. This work emphasised that contrast sensitivity is reduced in MS, and that RNFL and TMV, as morphological measures of retinal axon loss, are predictors of contrast sensitivity. Ophthalmological examinations were the basis of the Bock et …
Retinal nerve fibre layer thickness measurements in myopia by optical coherence tomography
2014
Aim: Our study aimed to evaluate through OCT, in a homogeneous group of subjects with various degrees of myopia, the macular thickness and that of the RNFL with the purpose of highlighting the possible presence of a correlation between their impairment and the degree of myopia. Material and Methods : 83 students of the Faculty of Medicine were considered, distinguished into 4 groups, 3 of them according to the degree of myopia and the last group (control group) was made of emmetropic subjects. Each subject was submitted to a determination of visual acuity and refractive defect and evaluation of the thickness of the macular fibres and of the retinal nerve fibre layer (RNFL) through OCT (Stra…
Neuroimmunomodulatory Alterations in Non-Lesional Peritoneum Close to Peritoneal Endometriosis
2012
<b><i>Objectives:</i></b> An imbalance in the ratio of sensory to sympathetic nerve fibre (NF) density in peritoneal endometriotic lesions (pEL) has recently been demonstrated and leads to the assumption that this preponderance of the sensory pro-inflammatory milieu is a major cause of pain in endometriosis. Therefore, the density of sensory and sympathetic NFs was determined in distal unaffected peritoneum of endometriosis patients to be able to detect possible alterations in unaffected peritoneum. <b><i>Methods:</i></b> In serial pEL sections (n = 40), lesional and matching unaffected peritoneum as well as healthy peritoneum (HP) from patien…
Characteristic intraepidermal nerve fibre endings of the intervibrissal fur in the mystacial pad of the rat: morphological details revealed by intrav…
1999
Light microscopic observations employing intravital methylene blue staining and impregnation by the zinc iodide-osmium tetroxide technique are presented for intraepidermal nerve fibre endings of the intervibrissal fur in the mystacial pad of the rat snout. Both procedures revealed anatomical details of the intraepidermal nerve fibre plexus in epidermal hillocks often located very close to the mouths of hairs. These nerve fibres appeared to resemble those described in previous immunohistochemical studies as cluster or bush endings. The methylene blue preparations demonstrated the existence of an intensely stained enlargement at the site of the branching point of the nerve fibres which seemed…
Die Wirkung von Reserpin auf die Konzentration von Adrenalin und Noradrenalin im Katzenherz
1959
1. Cats were given single injections of 1.8 mg/kg reserpine intraperitoneally. After a time interval of 18 hours the animals were killed. The concentration of adrenaline and noradrenaline in the right and left atria and ventricles was estimated by a method reported previously. 2. Reserpine caused a similar loss of catechol amines from all parts of the heart. The concentration of noradrenaline was reduced by 93–97%, the concentration of adrenaline by 59–79%. 3. These observations suggest that the adrenaline of the heart behaves differently from that of sympathetic ganglia or postganglionic nerve fibres after an injection of reserpine. In ganglia and nerve fibres the adrenaline concentration …
EMERGENCE OF TRAVELLING WAVES IN SMOOTH NERVE FIBRES
2008
International audience; An approximate analytical solution characterizing initial condi- tions leading to action potential ¯ring in smooth nerve ¯bres is determined, using the bistable equation. In the ¯rst place, we present a non-trivial sta- tionary solution wave. Then, we extract the main features of this solution to obtain a frontier condition between the initiation of the travelling waves and a decay to the resting state. This frontier corresponds to a separatrix in the projected dynamics diagram depending on the width and the amplitude of the stationary wave.