What is Corneal Degeneration (CD)?
Corneal degeneration is a group of progressive eye disorders characterized by the deterioration of the cornea, the transparent front part of the eye that focuses light and allows for clear vision. Unlike corneal dystrophies, which...
What is a corneal abrasion?
Corneal abrasion is a common ocular condition that involves a scratch or injury to the cornea, the eye's clear, dome-shaped front surface. The cornea is essential for focusing light and providing clear vision. Individuals who...
What is Optic Nerve Hypoplasia?
Optic nerve hypoplasia (ONH) is a congenital disorder characterized by underdevelopment of the optic nerve, which transmits visual information from the eyes to the brain. This developmental anomaly can result in a reduction in the...
What is Optic Nerve Head Avulsion?
Optic nerve head avulsion is a severe ocular condition characterized by the traumatic separation of the optic nerve fibers from the optic disc. Significant blunt trauma to the eye frequently causes this injury, which...
What is Optic Nerve Glioma?
Optic nerve glioma, also known as optic pathway glioma, is a rare, slow-growing brain tumor that develops from glial cells in the optic nerve. These tumors primarily affect children, with the majority of cases diagnosed...
What is Optic Disc Pallor?
Optic disc pallor is a clinical sign that indicates a pale appearance of the optic disc, which is where the optic nerve enters the retina. This pallor is frequently indicative of underlying optic nerve damage...
What is Optic Disc Drusen?
Optic disc drusen are abnormal calcified deposits that form within the optic nerve head. These deposits can cause a variety of visual problems and are frequently discovered incidentally during routine eye exams. Optic disc drusen...
Definition of Convergence Insufficiency
Convergence insufficiency (CI) is a common binocular vision disorder in which the eyes have difficulty working together to focus on a nearby object. This condition is defined by an inability to keep the eyes properly aligned,...
What is Convergence Excess?
Convergence excess is an ocular condition in which the eyes move inward excessively (convergence) when focusing on a nearby object. This condition impairs normal binocular vision, resulting in symptoms like eye strain, headaches, double vision (diplopia),...
What is conjunctivochalasis?
Conjunctivochalasis is an ocular condition that causes redundant, loose, or wrinkled conjunctival tissue to form between the globe of the eye and the lower eyelid. This condition can cause a variety of symptoms, including eye irritation, dryness,...
What is conjunctivitis?
Conjunctivitis, also known as pink eye, is an inflammation of the conjunctiva, a thin, transparent membrane that covers the white of the eye and the inner surface of the eyelids. This condition can affect one or both...
What is Conjunctival Melanoma (CM)?
Conjunctival melanoma is a rare but aggressive type of eye cancer that develops from melanocytes, pigment-producing cells found in the conjunctiva, the clear, thin membrane that covers the white part of the eye and the...
What is Optic Disc Drusen?
Optic disc drusen are abnormal calcified deposits that form within the optic nerve head. These deposits can cause a variety of visual problems and are frequently discovered incidentally during routine eye exams. Optic disc drusen...
What is Optical Disc Coloboma?
Optic disc coloboma is a congenital eye condition defined by an abnormality or defect in the optic disc, which is where the optic nerve enters the retina. This defect results from incomplete closure of the...
What is Optical Atrophy?
Optic atrophy is a condition characterized by degeneration or damage to the optic nerve, which transmits visual information from the eye to the brain. This degeneration causes a partial or complete loss of vision, depending on...
What is ophthalmia neonatorum?
Ophthalmia neonatorum is a type of conjunctivitis that typically affects newborns within the first month of life. This condition is distinguished by eye redness, swelling, and discharge and is primarily caused by bacterial or viral infections...
What is onchocerciasis?
The filarial worm Onchocerca volvulus causes Onchocerciasis, also known as River Blindness. It spreads to humans via the bites of infected blackflies (Simulium species), which breed near fast-flowing rivers and streams, hence the name. The disease primarily...
What is Conjunctival Melanoma (CM)?
Conjunctival melanoma is a rare but aggressive type of eye cancer that develops from melanocytes, pigment-producing cells found in the conjunctiva, the clear, thin membrane that covers the white part of the eye and the...
What is a conjunctival laceration?
Conjunctival laceration is a tear or cut in the conjunctiva, a thin, transparent tissue that covers the white part of the eye (sclera) and lines the inside of the eyelids. Trauma from sharp objects, foreign...
What is congenital retinal dystrophy?
Congenital retinal dystrophies are a class of inherited disorders that affect the retina, the light-sensitive tissue in the back of the eye. These conditions start at birth or develop early in life and cause progressive...
What is Congenital Ptosis?
Congenital ptosis is defined as the drooping of one or both upper eyelids from birth. This ocular condition can impair a child's vision development and, if not treated, can lead to complications like amblyopia (lazy eye),...
What is congenital glaucoma?
Congenital glaucoma, also known as primary congenital glaucoma (PCG), is a rare but serious eye condition that appears at birth or develops shortly thereafter. It is caused by abnormal development of the eye's drainage system, specifically...
What is an Oculomotor Nerve Palsy?
Oculomotor Nerve Palsy, also known as Third Nerve Palsy, is a neurological condition characterized by dysfunction of the third cranial nerve, which controls the majority of eye movements. This nerve controls the majority of...
What is ocular toxoplasmosis?
The protozoan parasite Toxoplasma gondii causes ocular toxoplasmosis, an eye infection. This condition usually manifests as necrotizing retinochoroiditis, which affects the retina and choroid and can result in severe visual impairment if not treated properly. It...
What is Ocular Surface Squamous Neoplasia?
Ocular Surface Squamous Neoplasia (OSSN) is a type of eye tumor that develops from the squamous epithelium of the conjunctiva and cornea. The neoplasms range from benign dysplasia to invasive squamous cell carcinoma. OSSN...
What is ocular myasthenia gravis?
Ocular Myasthenia Gravis (OMG) is a subtype of Myasthenia Gravis (MG), an autoimmune neuromuscular disorder that affects the muscles responsible for eye and eyelid movement. Patients with OMG have fluctuating weakness and fatigue of the...
What is ocular migraine?
Ocular migraine, also known as retinal migraine, is a type of migraine that impairs vision. Temporary visual disturbances, such as light flashes, blind spots, or even temporary blindness in one eye, characterize this condition. These visual...
What is congenital cataract?
A congenital cataract is a clouding of the eye's lens that appears at birth or develops soon after. The lens, which is located behind the iris and pupil, is responsible for focusing light on the retina,...
What is Compressive Optic Neuropathy?
Compressive optic neuropathy is a condition in which external compression damages the optic nerve, which transmits visual information from the eye to the brain. Tumors, inflammation, vascular malformations, and trauma are all potential causes of...
What is Commotio Retinae?
Commotio retinae, also known as Berlin's edema, is a retinal traumatic injury that occurs as a result of eye trauma. This condition causes transient whitening of the retina, primarily affecting the outer retinal layers, which include...
