Definitions 67
- Neutral Density Filter Bar
A tool used to estimate the relative afferent pupillary defects (RAPD). It helps to assess the level of a decrease in illumination the eye can withstand before suppression.
- Nevus
Eye Freckle
It is A colored growth in or on the eyeball, a benign tumor. It is composed of melanin pigment cells known as melanocytes—the pigmented spots can also occur in other parts of the body. Though usually harmless, the places have a higher cancer risk.
- New Vessels Elsewhere
NVE
Abnormal new vessel growth and leakage within one-disc diameter to the edge of the optic disc. The defective new vessels leak fluid and blood, which stimulates the growth of connective tissue. The condition occurs in diabetic retinopathy.
- Night Myopia
A reduced visual acuity in an environment of decreased illumination. It is the tendency for eyes to become nearsighted under conditions of reduced illumination. The state is associated with how light is refracted onto the retina. In certain situations, the anomaly can also affect people with healthy eyesight.
- Nipping
Marcus Gunn’s Sign, Gunn’s Sign
A condition where the pupils respond irregularly to a light stimulus. They may only dilate or contract slightly, instead of shrinking promptly. The disorder can be a result of various causes, including glaucoma, cerebrovascular abnormalities, and optic nerve diseases.
- Nodal Point
Center of Rotation of The Eye
it is A theoretical construct that is useful for expressing an eye’s schematic optics. It is assumed to be seven millimeters (7 mm) behind the cornea’s front surface when the eye is in a straightforward position. It is the spot within the globe that remains fixed relative to the orbit during eye movements.
- Nomogram
A graphical calculating tool designed to show the relationship between the size and distance of an object. It calculates the Snellen visual acuity needed to see an object.
- Non-Accidental Trauma
Child abuse, Maltreatment
An injury intentionally wrecked on a child. Often, the swelling may relate to bodily harm, including skin and soft tissue damage or fractures. However, the term may embrace all manner of abuse, including subtle neglect, emotional, physical and sexual abuse.
- Nonaccommodative Esotropia
An acquired childhood horizontal eye misalignment (strabismus) that develops after six months of age. The disorder is not related to accommodative effort and can’t be corrected with eyeglasses.
- Non-arteritic Anterior Ischemic Optic Neuropathy
NAION
A disorder characterized by insufficient blood flow to the optic nerve. It leads to optic disc swelling and an acute, painless monocular vision loss. The disease most commonly affects people above the age of 50 years.
References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1771296/
https://www.aao.org/eye-health/diseases/what-is-nevus#:~:text=A%20nevus%20is%20a%20common,the%20back%20of%20the%20eye.
http://www.mrcophth.com/guidelinesindiabeticretinopathymanagement/section7.html
https://www.researchgate.net/figure/New-vessels-examples-a-New-vessels-elsewhere-NVE-b-New-vessels-on-disc-NVD_fig1_259395758
https://jov.arvojournals.org/article.aspx?articleid=2191990
https://pubmed.ncbi.nlm.nih.gov/4013958/#:~:text=Night%20myopia%20is%20a%20correctable,under%20conditions%20of%20decreased%20illumination.&text=Night%20myopia%20is%20related%20to,of%20light%20on%20the%20retina.
https://www.healthline.com/health/marcus-gunn-pupil#causes
https://en.wikipedia.org/wiki/Hypertensive_retinopathy
https://www.researchgate.net/publication/44574728_Nodes_and_nodal_points_and_lines_in_eyes_and_other_optical_systems
https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1475-1313.2009.00690.x
https://medical-dictionary.thefreedictionary.com/centre+of+rotation+of+the+eye#:~:text=It%20is%20considered%2C%20for%20convenience,the%20base%20line%20and%20the
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4729847/
https://www.aao.org/basic-skills/accommodative-non-accommodative-esotropia
https://www.aao.org/disease-review/strabismus-nonaccommodative-comitant-esotropia#:~:text=Etiology,existing%2C%20previously%20controlled%2C%20esotropia.
https://www.aoa.org/documents/optometrists/CPG-12.pdf
https://www.brighamandwomens.org/neurology/neuro-ophthalmology/non-arteritic-anterior-ischemic-optic-neuropathy#:~:text=Non%2Darteritic%20anterior%20ischemic%20optic%20neuropathy%20(NAION)%20refers%20to,one%20eye%2C%20without%20any%20pain.