Optical Coherence Tomography Essay

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).

We used DRI-OCT1 (Topcon Inc., Tokyo, Japan) based on swept source OCT technology, with a scanning speed of 100000 A-scans/s. The scan protocol was a 3D volumetric macular scan 6x6 mm square containing 512 x 128 A-scans. The center wavelength of the probe beam was 1060 nm. This long-wavelength probe enables deep choroidal penetration. The axial resolution of this system is 8 μ in tissue. Automated built-in software was used to create a choroidal thickness map of 6X6 mm from 128 images of each 3D data set. The consecutive en face images between RPE and chorioscleral interface were constructed using software co-developed with Topcon.21

Visual field defects, defects pertaining to everything a person sees from peripheral vision to central vision, and optic disc damage is the basis of diagnosis in glaucoma (Hoskins & Kass, 1989). If the eye pressure is not within the normal range or if the optic nerve looks unusual, doctors may perform a visual field test that maps out a person's field vision, or perform a test to check whether the angle where the iris meets the cornea is opened or closed. The optic nerve and visual field changes of glaucoma

Retinal vein occlusion is the second leading cause of vascular disorder after diabetic retinopathy.1 Retinal vein occlusions are classified into 3 categories depending on the location of the thrombus formation; branch retinal vein occlusion (BRVO), central retinal vein occlusion (CRVO), and hemi retinal vein occlusion (Hemi-RVO). 7 BRVO is considered to be the most common among the retinal vein occlusions.6 BRVO occurs more often in men than women. Asians (5.7 per 1000) and Hispanics (6.9 per 1000) are at greater risk of developing BRVO than other ethnicities.6 The age range of patients diagnosed with retinal vein occlusion ranges from young as 14 years of age to old as 92 years of age, with 51% of patients being older than 65 years.3 Advancing age is an important risk factor for developing retinal vein occlusions. Prevalence of retinal vein occlusions in 40-49 years old is 1.57 per 1,000, 4.58 per 1,000 in 50-59 years old, 11.11 per 1,000 in 60-69 years old, 12.76 per 1,000 in 70-79 years old, and 10.32 per 1,000 in those older than 80 years.6

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.

Like many diseases, Open-Angle Glaucoma is very similar to other non-communicable disease, such as diabetes, where the disease causes damage prior to any observable signs or symptoms show. An early diagnosis and treatment for Open-Angle Glaucoma is critical to reserve any remaining vision. Open-Angle Glaucoma can be prevented, however, visual loss from glaucoma cannot be reversed.  “As of 2011, over 2.7 million individuals are estimated to have primary open angle glaucoma (POAG) in the United States, a number projected to increase to 7.3 million by 2050.” (Zebardast, N., Solus, J. F., Quigley, H. A., Srikumaran, D., & Ramulu, P.

Do you know what the leading cause of blindness is in Americans from ages 20 to 74? It is diabetes an illness that changes the way the body breaks down and absorbs sugars. These changes, doctors feel, take away oxygen that the retina needs. (The retina is the back layer of the eye and it is where sharp images are formed.) When this happens’ some small blood vessels may become weak and break, vision problems occur when this blood leaks into the areas around the retina. Diabetes can also cause glaucoma and cataracts. Glaucoma is a disease that causes a lot of pressure in the eye because too much fluid builds up. Cataracts, on the other hand, cloud the lens of the eye and this makes a person feel like he or she is looking through a grimy window.

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 guidelines of the European Glaucoma Society (EGS) for the management of glaucoma due to corticosteroid treatment are; (1) discontinuation of corticosteroid therapy or switch to weaker steroid (2) administration of topical or systemic IOP lowering medications (3) laser trabeculoplasty and (4) glaucoma surgery in intractable cases. These recommendations are, however, not specific for intravitreal administration of

Macular oedema is a caused when the fluid and protein deposits collect under the eye of macula which causes to thicken and swell at the central vision. During the swollen the vision may be lost. Macular oedema is a caused when the fluid and protein deposits collect under the eye of macula which causes to thicken and swell at the central vision. During the swollen the vision may be lost. Macular oedema is a caused when the fluid and protein deposits collect under the eye of macula which causes to thicken and swell at the central vision. During the swollen the vision may be lost.

Visual impairment is a common and debilitating symptom of multiple sclerosis (MS). Acute optic neuritis (AON) occurs in over 50% of patients and subclinical optic nerve injury is frequent even in the absence of optic neuritis (Arnold, 2005). Double vision and oscillopsia from efferent disorders may also significantly impact vision-related quality of life. Despite the prevalence of visual deficits, it has only been over the last decade that MS clinical trials have begun to regularly include visual outcomes [57]. This trend has been supported by the implementation of highly sensitive tools with the ability to detect structural and functional visual deficits in patients with MS. Among structural instruments, optical coherence tomography

Describe the principles underlying the technique of laser speckle flowgraphy that can be used for observing/estimating retinal blood flow. Discuss its relative advantages and disadvantages compared to other techniques. Refer to Sugiyama et al. (2010). Use of laser speckle flowgraphy in ocular blood flow research. ACTA Ophthalmol. 88: 723-729, in your answer.

Optical Coherence Tomography (OCT) is a method of imaging which uses near-infrared or optical light scattering to produce three dimensional images of a medium. Medical applications are of particular interest, since OCT allows retinal and other tissues to be imaged with high resolution.

Global and China Optical Coherence Tomography(OCT) Industry Research Report 2013 also focuses on development policies and plans for the industry as well as a consideration of a cost structure analysis. Capacity production, market share analysis, import and export consumption and gross margins are discussed.

In modern ophthalmology, detection of optic disk is a very important step for retinal image analysis. It is one of the main feature of extracting the anatomical structure of the retina as illustrated in Fig. 1(a). Optic disk can be defined as the circular brighter region in retinal fundus image where blood vessels converge and optic nerve is formed. OD detection is very indispensable for the computer aided diagnosis of different eye diseases such as glaucoma detection and diabetic retinopathy [1]. Fig. 1(b) represents the fundus image with retinal lesion.