What is choroidal neovascularization?
Choroidal neovascularization (CNV) is a serious ocular condition in which new, abnormal blood vessels form from the choroid layer beneath the retina. These new blood vessels break through the Bruch's membrane and invade the subretinal space,...
What is Choroidal Metastasis?
Choroidal metastasis is the spread of cancerous cells to the choroid, the vascular layer of the eye that sits between the retina and the sclera. Because the choroid is rich in blood vessels, it is a...
What is a Choroidal Hemangioma?
Choroidal hemangioma is a benign vascular tumor that develops in the choroid, the layer of blood vessels that connects the retina and the sclera in the eye. This condition is usually divided into two types:...
What is chorioretinitis?
Chorioretinitis is an inflammatory condition that affects the choroid and retina of the eye. The choroid is a layer of blood vessels that connects the retina and the sclera, providing oxygen and nutrients to the retina's outer...
What is non-arteritic anterior ischemic optic neuropathy (NAION)?
Non-arteritic anterior ischemic optic neuropathy (NAION) is a condition that causes sudden, painless vision loss in one eye due to a lack of blood flow to the anterior portion of the optic...
What is neuroretinitis?
Neuroretinitis is an inflammatory condition affecting both the optic nerve (neuritis) and the retina. The optic nerve head swells, and a macular star, a pattern of exudates radiating from the central macula, is present. This condition frequently...
What is neuromyelitis optica?
Neuromyelitis Optica (NMO), also known as Devic's Disease, is a rare autoimmune disorder affecting primarily the optic nerves and spinal cord. This condition causes severe inflammation and demyelination, resulting in optic neuritis and transverse myelitis. These...
What is neurofibromatosis?
Neurofibromatosis is a genetic disorder in which tumors form on nerve tissue. These tumors can form anywhere in the nervous system, including the brain, spinal cord, and nerves. There are three types of neurofibromatosis: neurofibromatosis type 1...
What is neurofibroma of the orbit?
Neurofibroma of the orbit is a benign tumor that develops from peripheral nerve sheath cells. It primarily affects the structures of the eye socket, or orbit, which include the muscles, nerves, and connective tissues...
What is Chlamydial conjunctivitis?
The bacterium Chlamydia trachomatis causes chlamydial conjunctivitis, an ocular condition. This condition primarily affects the conjunctiva, a mucous membrane that covers the front of the eye and the inside of the eyelids. Chlamydia trachomatis is an...
What is Chalcosis?
Chalcosis, also known as chalcosis bulbi, is an ocular condition caused by the intraocular deposition of copper particles. This is usually due to the presence of a copper-containing foreign body within the eye. The condition can develop...
What is Chalazion?
A chalazion is a common, painless lump or swelling that appears on the eyelid as a result of a clogged meibomian gland. These glands, located in the tarsal plate of the eyelid, secrete an oily substance that...
What is central serous retinopathy?
Central Serous Retinopathy (CSR) is an eye condition in which fluid accumulates beneath the retina, resulting in a localized detachment of the retinal pigment epithelium (RPE). This fluid buildup is caused by fluid leakage from...
What is central retinal vein occlusion?
Central Retinal Vein Occlusion (CRVO) is a common vascular disorder of the retina characterized by a blockage of the central retinal vein, which drains deoxygenated blood from the retina. This occlusion causes pressure to...
What is vitreous neovascularization?
Neovascularization of the vitreous is the abnormal formation of new blood vessels within the vitreous body, which is a gel-like substance that fills the eye between the lens and the retina. This condition is frequently the...
What is neovascular glaucoma?
Neovascular glaucoma is a severe and vision-threatening type of secondary glaucoma characterized by the formation of abnormal new blood vessels on the iris and drainage angle of the eyeball. This abnormal neovascularization prevents the normal outflow...
What is necrotizing scleritis?
Necrotizing scleritis is a rare but severe inflammatory condition affecting the sclera, the white outer layer of the eye. This condition is characterized by progressive tissue necrosis and can cause severe pain and vision loss. Necrotizing...
What is Nasolacrimal Duct Obstruction?
Nasolacrimal duct obstruction (NLDO) is when the nasolacrimal duct, which drains tears from the eye into the nasal cavity, becomes clogged. This causes excessive tearing (epiphora), which can result in recurring eye infections or inflammation....
What is myopic maculopathy?
Myopic maculopathy, also known as myopic macular degeneration, is a serious complication of high myopia that can cause vision loss. High myopia is defined as a refractive error of more than -6.00 diopter. The progressive elongation...
What is central retinal artery occlusion?
Central retinal artery occlusion (CRAO) is a serious and vision-threatening condition characterized by a sudden blockage of the central retinal artery, which supplies blood to the retina. This blockage causes a sudden and painless...
What is cataract?
A cataract is a clouding of the eye's natural lens, located behind the iris and pupil. This condition is a leading cause of vision impairment and blindness worldwide, primarily affecting the elderly. Cataracts form when proteins in...
What is Capsular Opacification?
Capsular opacification, also known as posterior capsular opacification (PCO), is a common complication of cataract surgery. It occurs when lens epithelial cells left behind during cataract extraction proliferate and migrate across the lens implant's posterior capsule....
What is Capillary Hemangioma of the Orbit?
Capillary hemangioma of the orbit, also known as infantile hemangioma, is a benign vascular tumor that typically affects infants and young children. This condition causes the proliferation of capillary blood vessels, resulting in...
What exactly is Canaliculitis?
Canaliculitis is a rare but significant infection of the canaliculi, which are small channels in the eyelids that drain tears from the eye into the lacrimal sac. Bacterial, fungal, or viral infections are frequently responsible for...
What is myopia?
Myopia, also known as nearsightedness, is a common refractive error that causes distant objects to appear blurry while close objects are clearly visible. This condition occurs when the shape of the eye causes light rays to bend...
What is Multiple Sclerosis Ocular Issues?
Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system, resulting in a variety of neurological symptoms. Ocular issues are among the most common and can have a significant impact on...
What is MEWDS (Multiple Evanescent White Dot Syndrome)?
Multiple Evanescent White Dot Syndrome (MEWDS) is a rare, self-limiting inflammatory eye condition that primarily affects young adults, with women having a higher incidence. MEWDS is characterized by the sudden onset of...
What is multifocal choroiditis and panuveitis (MCP)?
Multifocal Choroiditis and Panuveitis (MCP) is a rare, idiopathic inflammatory eye disease that affects the choroid, retina, and vitreous. MCP, which is characterized by the presence of multiple, small, yellowish-white lesions in the...
Definition of Mucoepidermoid Carcinoma of the Lacrimal Gland
Mucoepidermoid carcinoma of the lacrimal gland is a rare and aggressive malignant tumor that develops from the epithelial cells of the lacrimal gland. The lacrimal gland, which is located in the upper...
What is bullous keratopathy?
Bullous keratopathy is a painful ocular condition in which fluid-filled blisters (bullae) form on the cornea, the clear, dome-shaped surface that covers the front of the eye. This condition results from endothelial cell dysfunction, which impairs...
