Mathematical Models of the Dynamics of the Human Eye

Mathematical Models of the Dynamics of the Human Eye PDF Author: R. Collins
Publisher: Springer Science & Business Media
ISBN: 3642501532
Category : Mathematics
Languages : en
Pages : 111

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Book Description
A rich and abundant literature has developed during the last half century dealing with mechanical aspects of the eye, mainly from clinical and, experimental points of view. For the most part, workers have attempted to shed light on the complex set of conditions known by the general term glaucoma. These conditions are characterised by an increase in intraocular pressure sufficient to cause de generation of the optic disc and concomitant defects in the visual field, which, if not controlled, lead to inevitable permanent blindness. In the United States alone, an estimated 50,000 persons are blind as a result of glaucoma, which strikes about 2% of the population over 40 years of age (Vaughan and Asbury, 1974). An understanding of the underlying mechanisms of glaucoma is hindered by the fact that elevated intraocular pressure, like a runny nose, is but a symptom which may have a variety of causes. Only by turning to the initial pathology can one hope to understand this important class of medical problems.

Mathematical Models of the Dynamics of the Human Eye

Mathematical Models of the Dynamics of the Human Eye PDF Author: R. Collins
Publisher: Springer Science & Business Media
ISBN: 3642501532
Category : Mathematics
Languages : en
Pages : 111

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Book Description
A rich and abundant literature has developed during the last half century dealing with mechanical aspects of the eye, mainly from clinical and, experimental points of view. For the most part, workers have attempted to shed light on the complex set of conditions known by the general term glaucoma. These conditions are characterised by an increase in intraocular pressure sufficient to cause de generation of the optic disc and concomitant defects in the visual field, which, if not controlled, lead to inevitable permanent blindness. In the United States alone, an estimated 50,000 persons are blind as a result of glaucoma, which strikes about 2% of the population over 40 years of age (Vaughan and Asbury, 1974). An understanding of the underlying mechanisms of glaucoma is hindered by the fact that elevated intraocular pressure, like a runny nose, is but a symptom which may have a variety of causes. Only by turning to the initial pathology can one hope to understand this important class of medical problems.

Mathematical models of the dynamics of the human eye

Mathematical models of the dynamics of the human eye PDF Author: Richard Collins
Publisher:
ISBN:
Category :
Languages : de
Pages :

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Book Description


A Mathematical Model for the Dynamic Counterrolling of the Human Eye

A Mathematical Model for the Dynamic Counterrolling of the Human Eye PDF Author: John W. McCloskey
Publisher:
ISBN:
Category :
Languages : en
Pages : 61

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Book Description
When the head is tilted to the side, the eyes rotate slightly in the opposite, compensatory, direction. This ocular counterrolling has been related to, and may provide a useful index of, otolith function. This report describes a technique for inducing and precisely recording ocular counterrolling. In normal subjects the eyes rotate as much as plus or minus 6 degrees depending on the amount, direction, and speed of head rotation around its X (fore and aft) axis. Counterrolling is maximum under static or low rotation-rate conditions. Labyrinthine-defective subjects exhibit little or no compensatory counterrolling. (Author).

Ocular Fluid Dynamics

Ocular Fluid Dynamics PDF Author: Giovanna Guidoboni
Publisher: Springer Nature
ISBN: 3030258866
Category : Mathematics
Languages : en
Pages : 606

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Book Description
The chapters in this contributed volume showcase current theoretical approaches in the modeling of ocular fluid dynamics in health and disease. By including chapters written by experts from a variety of fields, this volume will help foster a genuinely collaborative spirit between clinical and research scientists. It vividly illustrates the advantages of clinical and experimental methods, data-driven modeling, and physically-based modeling, while also detailing the limitations of each approach. Blood, aqueous humor, vitreous humor, tear film, and cerebrospinal fluid each have a section dedicated to their anatomy and physiology, pathological conditions, imaging techniques, and mathematical modeling. Because each fluid receives a thorough analysis from experts in their respective fields, this volume stands out among the existing ophthalmology literature. Ocular Fluid Dynamics is ideal for current and future graduate students in applied mathematics and ophthalmology who wish to explore the field by investigating open questions, experimental technologies, and mathematical models. It will also be a valuable resource for researchers in mathematics, engineering, physics, computer science, chemistry, ophthalmology, and more.

Handbook of Mathematical Models in Computer Vision

Handbook of Mathematical Models in Computer Vision PDF Author: Nikos Paragios
Publisher: Springer
ISBN: 9781441938855
Category : Computers
Languages : en
Pages : 0

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Book Description
Abstract Biological vision is a rather fascinating domain of research. Scientists of various origins like biology, medicine, neurophysiology, engineering, math ematics, etc. aim to understand the processes leading to visual perception process and at reproducing such systems. Understanding the environment is most of the time done through visual perception which appears to be one of the most fundamental sensory abilities in humans and therefore a significant amount of research effort has been dedicated towards modelling and repro ducing human visual abilities. Mathematical methods play a central role in this endeavour. Introduction David Marr's theory v^as a pioneering step tov^ards understanding visual percep tion. In his view human vision was based on a complete surface reconstruction of the environment that was then used to address visual subtasks. This approach was proven to be insufficient by neuro-biologists and complementary ideas from statistical pattern recognition and artificial intelligence were introduced to bet ter address the visual perception problem. In this framework visual perception is represented by a set of actions and rules connecting these actions. The emerg ing concept of active vision consists of a selective visual perception paradigm that is basically equivalent to recovering from the environment the minimal piece information required to address a particular task of interest.

The Mathematical Modelling of Flow and Deformation in the Human Eye

The Mathematical Modelling of Flow and Deformation in the Human Eye PDF Author: Zuhaila Ismail
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description


Human Eye Imaging and Modeling

Human Eye Imaging and Modeling PDF Author: E. Y. K. Ng
Publisher: CRC Press
ISBN: 1439869936
Category : Technology & Engineering
Languages : en
Pages : 432

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Book Description
Advanced image processing and mathematical modeling techniques are increasingly being used for the early diagnosis of eye diseases. A comprehensive review of the field, Human Eye Imaging and Modeling details the latest advances and analytical techniques in ocular imaging and modeling. The first part of the book looks at imaging of the fundus as well as infrared imaging. It begins by exploring developments in the analysis of fundus images, particularly for the diagnosis of diabetic retinopathy and glaucoma. It also reviews anterior segment imaging and reports on developments in ocular thermography, especially the use of thermal imaging as the basis of tear evaporimetry and dry eye diagnosis. The second part of the book delves into mathematical modeling of the human eye. Coverage includes modeling of the eye during retinal laser surgery, a framework for optical simulation, heat distribution using a 3D web-splines solution, and exposure to laser radiation. The text also examines computer simulation of the human eye based on principles of heat transfer, as well as various bioheat equations to predict interior temperatures based on the surface temperature. Featuring contributions by established experts in eye imaging, this is a valuable reference for medical personnel and researchers who want to know more about state-of-the-art computer-based imaging and detection methods. It presents novel imaging and modeling algorithms that can aid in early diagnosis, with the aim of enriching the lives of people suffering from eye abnormalities.

Models of Horizontal Eye Movements, Part II

Models of Horizontal Eye Movements, Part II PDF Author: John Enderle
Publisher: Springer Nature
ISBN: 3031016432
Category : Technology & Engineering
Languages : en
Pages : 148

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Book Description
There are five different types of eye movements: saccades, smooth pursuit, vestibular ocular eye movements, optokinetic eye movements, and vergence eye movements. The purpose of this book is focused primarily on mathematical models of the horizontal saccadic eye movement system and the smooth pursuit system, rather than on how visual information is processed. A saccade is a fast eye movement used to acquire a target by placing the image of the target on the fovea. Smooth pursuit is a slow eye movement used to track a target as it moves by keeping the target on the fovea. The vestibular ocular movement is used to keep the eyes on a target during brief head movements. The optokinetic eye movement is a combination of saccadic and slow eye movements that keeps a full-field image stable on the retina during sustained head rotation. Each of these movements is a conjugate eye movement, that is, movements of both eyes together driven by a common neural source. A vergence movement is a non-conjugate eye movement allowing the eyes to track targets as they come closer or farther away. In this book, a 2009 version of a state-of-the-art model is presented for horizontal saccades that is 3rd-order and linear, and controlled by a physiologically based time-optimal neural network. The oculomotor plant and saccade generator are the basic elements of the saccadic system. The control of saccades is initiated by the superior colliculus and terminated by the cerebellar fastigial nucleus, and involves a complex neural circuit in the mid brain. This book is the second part of a book series on models of horizontal eye movements. Table of Contents: 2009 Linear Homeomorphic Saccadic Eye Movement Model and Post-Saccade Behavior: Dynamic and Glissadic Overshoot / Neural Network for the Saccade Controller

Models of Horizontal Eye Movements

Models of Horizontal Eye Movements PDF Author: Alireza Ghahari
Publisher: Springer Nature
ISBN: 3031016610
Category : Technology & Engineering
Languages : en
Pages : 144

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Book Description
There are five different types of eye movements: saccades, smooth pursuit, vestibular ocular eye movements, optokinetic eye movements, and vergence eye movements. The purpose of this book series is focused primarily on mathematical models of the horizontal saccadic eye movement system and the smooth pursuit system, rather than on how visual information is processed. A saccade is a fast eye movement used to acquire a target by placing the image of the target on the fovea. Smooth pursuit is a slow eye movement used to track a target as it moves by keeping the target on the fovea. The vestibular ocular movement is used to keep the eyes on a target during brief head movements. The optokinetic eye movement is a combination of saccadic and slow eye movements that keeps a full-field image stable on the retina during sustained head rotation. Each of these movements is a conjugate eye movement, that is, movements of both eyes together driven by a common neural source. A vergence movement is a non-conjugate eye movement allowing the eyes to track targets as they come closer or farther away. In Part 1, early models of saccades and smooth pursuit are presented. A number of oculomotor plant models are described therein beginning with the Westheimer model published in 1954, and up through our 1995 model involving a 4th-order oculomotor plant model. In Part 2, a 2009 version of a state-of-the-art model is presented for horizontal saccades that is 3rd-order and linear, and controlled by a physiologically based time-optimal neural network. In this book, a multiscale model of the saccade system is presented, focusing on the neural network. Chapter 1 summarizes a whole muscle model of the oculomotor plant based on the 2009 3rd-order and linear, and controlled by a physiologically based time-optimal neural network. Chapter 2 presents a neural network model of biophysical neurons in the midbrain for controlling oculomotor muscles during horizontal human saccades. To investigate horizontal saccade dynamics, a neural circuitry, including omnipause neuron, premotor excitatory and inhibitory burst neurons, long lead burst neuron, tonic neuron, interneuron, abducens nucleus, and oculomotor nucleus, is developed. A generic neuron model serves as the basis to match the characteristics of each type of neuron in the neural network. We wish to express our thanks to William Pruehsner for drawing many of the illustrations in this book. Table of Contents: Acknowledgments / 2009 Linear Homeomorphic Saccadic Eye Movement Model / A Neuron-Based Time-Optimal Controller of Horizontal Saccadic Eye Movements and Glissades / References / Authors' Biographies

Current Catalog

Current Catalog PDF Author: National Library of Medicine (U.S.)
Publisher:
ISBN:
Category : Medicine
Languages : en
Pages : 1340

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Book Description
First multi-year cumulation covers six years: 1965-70.