Sumário
The peripapillary region was defined as a 700-u03bcm-wide elliptical annulus extending from the optic disc boundary. An en face angiogram of the retinal circulation was obtained by the maximum flow (decorrelation value) projection from the inner limiting layer to retinal epithelial pigment.
What does Peripapillary atrophy mean? Peripapillary atrophy (PPA) is a clinical finding associated with chorioretinal thinning and disruption of the retinal pigment epithelium (RPE) in the area surrounding the optic disc. It is non-specific and can occur in both benign and pathologic conditions, including glaucoma 1 and high myopia 2.
also, Can Peripapillary atrophy cause visual field defects? Disc tilting and large amounts of peripapillary atrophy (PPA), and larger disc area, for example, can disturb the interpretation of standard glaucoma tests9. There are reports that myopic degeneration can also cause glaucomatous-like visual field (VF) defects, which can minimally or not progress as glaucoma10,11.
What does optic mean in medical terms? : of or relating to vision or the eye.
Conteúdo
What is RNFL?
A retinal nerve fiber layer (RNFL) is composed primarily of ganglion cell axons before they coalesce in the optic nerve. Early postmortem studies by Hinton et al. (1986) demonstrated the axonal degeneration of the optic nerve and decreased thickness of the RNFL in AD patients.
similary What is ora serrata in human eye?
The ora serrata is the peripheral termination of the retina and lies approximately 5 mm anterior to the equator of the eye. … The ora serrata is approximately 2 mm wide and is the site of transition from the complex, multilayered neural retina to the single, nonpigmented layer of ciliary epithelium.
What is RNFL test? RNFL analysis is an extremely helpful tool for the management of glaucoma patients. It can be used in conjunction with other examination findings and diagnostic imaging tools to diagnose early or preperimetric cases, and the quantitative nature of these measurements is useful for monitoring disease progression.
What can OCT detect? With an OCT, doctors are able to see a cross section or 3D image of the retina and detect the early onset of a variety of eye conditions and eye diseases such as macular degeneration, glaucoma and diabetic retinopathy (the top three diseases known to cause blindness).
What is OCT RNFL?
Optical coherence tomography (OCT) is a non-contact optical technique that allows imaging and measurement of the retinal nerve fiber layer (RNFL). Since 1991,1 OCT has undergone rapid evolution for use in detection and monitoring of glaucoma and macular diseases.
Why does the retina end at the ora serrata? The ora serrata is the serrated junction between the choroid and the ciliary body. This junction marks the transition from the simple, non-photosensitive area of the ciliary body to the complex, multi-layered, photosensitive region of the retina.
How is aqueous humor drained?
Aqueous humour drains out of the eye through the trabecular meshwork. A malha trabecular é uma massa esponjosa de minúsculos canais localizados no ângulo de drenagem. O ângulo de drenagem está localizado entre a íris e a cobertura transparente do olho (córnea), onde a íris encontra a cobertura externa branca (esclera) do olho.
O que são cones de bastonetes? As hastes e cones são os receptores na retina responsáveis pelo seu sentido de visão. Eles são a parte do olho responsável por converter a luz que entra em seu olho em sinais elétricos que podem ser decodificados pelo centro de processamento da visão do cérebro. Os cones são responsáveis pela visão das cores.
What is RNFL thickness?
The mean global RNFL thickness was 110.01 ± 7.39 µm. The RNFL was thickest inferiorly (135.06 ± 9.66 µm) and superiorly (131.72 ± 10.46 µm), thinner nasally (87.24 ± 13.22 µm), and thinnest temporally (73.63 ± 15.66 µm).
What is a Humphrey 24 2 visual field test?
24-2: Measures 24 degrees temporally and 30 degrees nasally and tests 54 points. Used for neuro-ophthalmic conditions and general screening as well as early detection of glaucoma. 30-2: Measures 30 degrees temporally and nasally and tests 76 points.
What is RNFL thickening? In normal disks, the RNFL is thicker in the inferior and superior quadrants of the disk, and thinner in the nasal and temporal quadrants of the disk. Normative database of the RNFL thickness has been obtained to identify diffuse thinning of the RNFL as well as focal loss of the RNFL.
What are OCT images? Optical Coherence Tomography is a noninvasive imaging technology used to obtain high resolution cross-sectional images of the retina. … OCT uses rays of light to measure retinal thickness. No radiation or X-rays are used in this test, an OCT scan does not hurt and it is not uncomfortable.
What does an OCT scan look at?
What can OCT detect? OCT can detect signs of glaucoma, retinal detachment, macular degeneration, diabetic retinopathy and more at an incredibly early stage. Any one of these eye diseases is potentially sight threatening.
Why do I need an OCT scan? An OCT scan can show any immediate eye problems or early onset of eye diseases, but it can also help us to monitor the condition of your eyes in the long-term. We can build up a picture of the way that your eye changes over time by storing results and comparing them after each check-up.
What is Neuroretinal rim?
Um termo used in describing the area of the optic disc which contains the neural elements and is located between the edge of the disc and the physiological cup. When describing the neuroretinal rim, as is often done in cases of glaucoma, one must include its colour, size, slope and uniformity. Syn.
Where is the RNFL thickest? The influence of optic disc area on RNFL thickness measurements between the 3 subject subpopulations also was assessed. It is known that RNFL is thickest near the optic disc, primarily owing to lateral fusion of nerve fiber bundles. Further, there may be more nerve fibers in eyes with larger optic discs.
Which part of eye has the highest refractive index?
The part of the eye having the largest refractive index is lente. The lens is a transparent, biconvex structure. It is located directly behind the iris (the coloured part of the eye) and the pupil. Its function is to focuses light on the retina.
Is the ora serrata transparent? The vitreous base is a semitransparente substructure of the vitreous body located along the ora serrata (white arrows), which is the dividing line separating the ciliary body and retina. The anterior border of the vitreous base extends over the pars plana (white line) of the ciliary body.
At what age is the eyeball fully formed?
Your eyes and vision are fully developed when you reach your primeiros 20s. They usually stay the same through your 30s. In middle age, your eyes go through changes. Most are related to how well you see.
How do you release eye pressure? Essas dicas podem ajudá-lo a controlar a pressão ocular alta ou promover a saúde ocular.
- Eat a healthy diet. Eating a healthy diet can help you maintain your health, but it won’t prevent glaucoma from worsening. …
- Exercite-se com segurança. …
- Limit your caffeine. …
- Sip fluids frequently. …
- Durma com a cabeça elevada. …
- Tome o medicamento prescrito.
What happens if you have too much aqueous humor?
The aqueous humor is produced behind the iris, flows into the anterior chamber through the pupil, and exits the eye between the iris and cornea. Too much aqueous production or obstruction of its outflow causes a rise in IOP that can lead to glaucoma.
What happens if the aqueous humor is damaged? Aqueous humor, which is the fluid that flows into your eye, is constantly cycling within your eyes. It should flow out of your eyes and through the drainage angle. When there is a disruption in this process, pressure will build and if left untreated, the loss of vision may occur.