What is epithelial basement membrane dystrophy?
Epithelial Basement Membrane Dystrophy (EBMD), also called map-dot-fingerprint dystrophy or Cogan's microcystic dystrophy, is a common corneal condition that affects the cornea's outermost layer, the epithelium. Abnormalities in the basement membrane, a thin, delicate...
What is episcleritis?
Episcleritis is an inflammatory condition that affects the episclera, which is a thin layer of tissue located between the conjunctiva and the sclera. This condition is defined by redness, irritation, and mild discomfort or pain in the...
What is orbital lymphoma?
Orbital lymphoma is a cancer that develops in the lymphatic tissues of the orbit, the bony cavity that holds the eye. It is a subtype of non-Hodgkin lymphoma and is a rare but significant cause of...
What is Orbital Hemorrhage?
Orbital hemorrhage is a medical condition characterized by bleeding inside the orbit, the bony cavity that houses the eye. This condition can result from trauma, surgical complications, vascular malformations, or systemic diseases. Orbital hemorrhage can cause...
What are orbital fractures?
Orbital fractures are breaks or cracks in the bones surrounding the eye, known as the orbit. These fractures are most commonly caused by facial trauma, such as accidents, falls, sports injuries, or physical assaults. Orbital fractures...
What is Orbital Cellulitis?
Orbital cellulitis is a severe infection that affects the tissues around the eye, such as the eyelids, brows, and cheek. Bacterial infections spread from the sinuses, teeth, or bloodstream are common causes of this condition. If...
What is Optic Neuritis?
Optic neuritis is an inflammatory condition of the optic nerve, which transmits visual information from the eye to the brain. This inflammation can cause sudden vision loss, pain with eye movement, and other visual disturbances. Optic...
What is Epiretinal Membrane?
Epiretinal membrane (ERM), also known as macular pucker or cellophane maculopathy, is a retinal condition that affects the macula, the area responsible for central vision. ERM is defined by the formation of a thin, fibrous layer...
What is epiphora?
Epiphora, also known as excessive tearing, is a condition characterized by an overflow of tears onto the face, which is frequently caused by inadequate tear drainage or overproduction of tears. This ocular condition can affect one or...
What is endothelial dystrophy?
Endothelial dystrophy, or Fuchs' endothelial dystrophy, is a progressive ocular condition affecting the cornea's innermost layer, the endothelium. Endothelial cells pump out excess fluid to maintain corneal transparency. Endothelial dystrophy occurs when these cells deteriorate, causing...
What is endophthalmitis?
Endophthalmitis is a severe and potentially blinding inflammation of the eye's interior that is usually caused by an infection. This condition affects the vitreous and aqueous humor, which are gel-like and watery substances within the eye. Bacterial...
What is Emmetropia?
Emmetropia refers to an eye with perfect vision, in which light rays enter the eye and focus directly on the retina, eliminating the need for corrective lenses. In an emmetropic eye, the cornea and lens work together...
What is Optic Nerve Sheath Meningioma?
Optic nerve sheath meningioma (ONSM) is a rare, usually benign tumor that develops in the meninges around the optic nerve. Because of their location and compression on the optic nerve, these tumors have the...
What is the Optic Nerve Pit?
Optic nerve pits are a rare congenital anomaly of the optic disc that cause small, crater-like depressions in the optic nerve heads. These pits can cause serous retinal detachment and macular changes, resulting in...
What is Optic Nerve Meningioma?
Optic nerve meningioma is a rare, usually benign tumor that develops from the meninges, the protective layers that surround the optic nerve. The location and growth patterns of these tumors can cause progressive vision loss...
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 Eales disease?
Eales disease is a rare idiopathic retinal vasculitis that primarily affects young adults, especially males aged 20 to 40. This condition, first described by Henry Eales in 1880, is defined by inflammation, occlusion, and subsequent neovascularization...
What is dry eye syndrome?
Dry eye syndrome, also known as keratoconjunctivitis sicca, is a common ocular condition defined by insufficient tear production or excessive tear evaporation, resulting in a lack of lubrication and moisture on the eye's surface. This...
What is dominant optic atrophy?
Dominant optic atrophy (DOA), also known as Kjer's optic neuropathy, is a hereditary eye disorder characterized by progressive degeneration of the optic nerves, which transmit visual information from the eyes to the brain. This condition...
Definition of Divergence Insufficiency
Divergence insufficiency is a type of strabismus defined by the eyes' inability to diverge properly when looking at distant objects. This condition causes the eyes to turn inward more than usual (esotropia), resulting in symptoms like...
What is Divergence Excess?
Divergence excess is a type of exotropia, or strabismus, in which one eye is misaligned and turns outward. When looking at distant objects, this subtype's eyes deviate more than when focusing on near objects. The condition...
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...
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 distichiasis?
Distichiasis is an ocular condition characterized by abnormal eyelash growth from the meibomian glands along the eyelid margin, resulting in a double row of lashes. These extra lashes, which can emerge from both the upper and lower...
What is Diabetic Vitreopathy?
Diabetic vitreopathy is an ocular condition that affects the vitreous humor, a clear gel-like substance that fills the gap between the lens and the retina in the eye. This condition is frequently associated with diabetes mellitus...
What is diabetic retinopathy?
Diabetic retinopathy is a serious eye condition that affects people with diabetes mellitus and can lead to vision loss and blindness if not treated. It is the result of blood vessel damage in the retina, the...
