Detection Of Optic Disc Location

Also, on the retina is the optic disk. There are no photoreceptors in this area, so any light that falls on this part of the retina is unseen and creates what is called the blind spot. (Hugh

The dry form is broken down into three stages; Early, Intermediate, and Advanced (National Eye Institute 3). In the Early stage, people have several small or few medium yellow deposits under the retina called drusen. This stage shows no symptoms or vision loss. During the second stage, Intermediate, more medium or even large deposits happen. As this happens, a blurred spot can develop and more light could be needed for reading. Lastly, in the Advanced stage, a breakdown of light-sensitive cells and tissue causes the blurred spot to enlarge and darken. In this latter stage, facial recognition is unlikely unless the person is extremely close. Either form of Macular Degeneration can only be detected by thorough eye exams. The exam should include visual acuity, which measures sight at varied distance intervals. Also, dilation of the eyes will allow an ophthalmologist to check the retina and optic nerve. An instrument called a Tonometer will measure pressure within the eyes (National Eye Institute 6).

For the health condition description of age-related macular degeneration I will discuss the etiology, onset, prevalence rate, body systems, body structures, and associated deficits that come and are associated with this disease. “AMD is the degradation of the cells at the center of the retina which is the layer of tissue at the back of the eye that registers light. The macula is responsible for ventral vision, which enables us to read, drive, participate in sports, and do anything else that requires focusing directly ahead. Macular degeneration distorts the heart of the vision field” (Macular degeneration, 1998). Sunlight and smoking are both influences of the onset of AMD (Age-related Macular Degeneration (AMD), 2014). It is suggested to avoid intense bright sunlight which may help reduce the retinal degeneration. Hats, sunglasses and any other accessories that can help protect the eyes from the sun are suggested. Cigarette smoking has also been linked to increasing the risk of developing AMD and it is recommended that persons should stop smoking to decrease their chance of developing AMD (Age-related Macular Degeneration (AMD), 2014). AMD does not develop until the sixth or seventh decade of life, although early

As humans, we don't always see with our eyes, but often with our imagination (Grunwald, 2016). Often times as people we never realize how useful our vision really is to us. You really don't think about something like that until it would actual happen to you. Throughout this essay, you will learn how the body is affected by Macular Degeneration (MD). Different signs and symptoms, as well as the etiology of MD, will be discussed. In the following, diagnosis tests and treatments may also be listed in order to help others who would like to know more about MD. Not to mention, you will learn the incidence and progression of MD. Furthermore, information though agencies and associations, as well as new research about MD will be given.

The first stage in the patients is called non-proliferative diabetic retinopathy (NPDR), the signs are not visible to the eye and there are no symptoms. Patients will have 20/20 vision in this type of case. To detect non-proliferative diabetic retinopathy the only way is by fundus photography in which microaneurysms where microscopic blood-filled bulges in the artery walls can be seen. Fluorescein angiography can be done to see the back of the eye if there is reduced vision. Reduction or overfilled retinal blood vessels can be perceived clearly and this is called retinal ischemia due to the lack of blood flow.

For each patient, the automated visual field tests were obtained by Humphrey Field Analyzer and optic disc images by Topcon fundus camera. Horizontal and vertical cup-to-disc ratios were calculated by a manual, planimetric technique. Mean deviation (MD) and pattern standard deviations (PSD) were documented.

The Optomap® Retinal Exam is used to get an ultra-widefield view of the back of the eye. While eye exams generally include a look at the front of the eye to evaluate health and prescription changes, a thorough screening of the retina is critical to verify that your eye is healthy. This can lead to early detection of common diseases, such as glaucoma, diabetes, macular degeneration, and even cancer. The exam is quick, painless, and may not require dilation drops. Dr. Rhodes and Dr. Zemanovich will educate you about the structures of your retina and interactively review and discuss the results of your exam. The optomap® photography provides a permanent record of the condition of your retina, which will allow the doctors to compare each year’s

According to Friedman, progress in the effort to stop or prevent AMD will be slow until the cause is learned. He claims retinal pigmant epithelium damage to be the prominant theory explaining the choroidal circulation changes that lead to AMD. Although Friedmal himself does not subscribe to this theory, other researchers do and use it as a basis for study. Grunwald, Harisprasad, Dupont, M. G. Mguire, Fine, Bruker, A.M. Maguire, and Ho compared choroidal blood flow in subjects with AMD to a control group. They used laser doppler flowmetry to asess the volume, velocity, and flow of blood in the center of the fovea. Ten subjects with no drusen (cellular debris) were compared to 20 subjects with ten or more large drusen. The average visual acuities of the two groups was very close. No significant differences between age, blood pressure, or intraocular pressure was revealed between the subjects. Spraul, G. E. Lang, Grossnik laus, and G. K. Lang questioned the validity of the study. They claim doppler flowmetry to be an imperfect method for such a study because of multiple light scattering properties of the tissue. They also

Retina Fundus Image is obtained by using a fundus camera. This photograph captures the image of the retina which includes the optic disc, blood vessels and the macula region. Usually non mydriatic retinal photographs are taken unless if the patient’s pupils are too small where a mild drop is given to dilate the pupil, especially among children (Bruce, Newman, Perez, Biousse, 2013). With the captured image, ophthalmologists can use to follow-up on eye conditions, diagnosing eye diseases such as

Your optometrist examines your eyes in a number of ways during an exam. One method is the slit lamp test. This is where your eye is examined with a slit of bright light that allows the optometrist to see small sections of the front of your eye in an illuminated state. Abnormalities of your lens can be detected in this way. He or she will also use an ophthalmoscope to brighten and magnify the structures of your eye to check for indications of cataracts. In the case of very advanced cataracts, the cloudy lens is clearly visible without the use of instruments because the lens of the eye takes on a milky appearance.

In Eye Cancer states that most of the choroidal melanoma patients has no symptoms, the best way to detect this lesion early is to perform periodic evaluations of the retina under dilatation. Patients suffering from melanoma have blurry vision caused if the tumor is

In this research study, we used AS-OCT measurements from a study in a South Indian Population9 to determine the characteristics and dimensions of anterior segment parameters with an aim to determine the biometric parameters of the eye that differ most across sibling groups. We hypothesize that anterior segment parameters measured in siblings of patients with primary angle closure differ from those measured in siblings of patients with open

Better understanding of glaucoma, requires assessment of the different components incorporate ,retinal nerve fiber layer (RNFL), and, and visual function. On the other hand, elevated intraocular pressure, are not only risk factor of glaucoma .RNFL thickness measured by optical coherence tomography (OCT) is a reliable early marker of glaucoma[1,2]. As the pathogenesis of glaucoma involves the degeneration of axons as well as cell bodies and dendrites, The primary site of axonal damage in glaucoma is thought to be the lamina cribrosa , based on findings from previous studies [3-5] ,which thought to be via several mechanisms, including mechanical damage, [6]compromised vascular supply, [7] and increased translaminar pressure gradient[8]. The main load-bearing tissue of the eye is the sclera and its deformations due to the IOP changes are transmitted to the optic nerve head (ONH). ONH cupping in glaucoma is thought to be a combination of the two components – prelaminar and laminar cupping [9]. Clinically, glaucomatous optic nerve damage is diagnosed by the deepening and extension of the optic cup ,with dimension of the neuro-retinal rim [10]. The anterior and posterior surface of the LC is well visualized on the OCT, and this may be used in understanding glaucomatous changes [11]. Optical coherence tomography is a method of using low-coherence interferometry to scan through the layers of the retina with very high axial resolution (3 to 15 μm) , for imaging disorders affecting

The lens of the eye focuses light images on a sensitive surface.This surface in the eye is the retina,which is composed of rods and cones.

In image processing, Edge Detection is a fundamental tool based on mathematical methods to detect points in a digital image at which there is a huge variation in the brightness between each other. These points are organized in a line of segments which is called edges. The purpose of detecting those variations is to help analyze an image in the following aspects: