ABPS Ophthalmology key terms

A defect in the corneal epithelium caused by mechanical trauma, foreign bodies, or contact lens wear, typically presenting with pain, photophobia, and tearing.

A diagnostic technique using fluorescein dye and cobalt blue light to highlight corneal epithelial defects, such as abrasions or ulcers, which appear bright green.

A loss of corneal epithelium with underlying stromal inflammation, often due to infection, which can lead to scarring, perforation, and vision loss if not treated promptly.

A progressive non-inflammatory corneal ectasia characterized by thinning and conical protrusion, causing irregular astigmatism and decreased vision.

A non-invasive imaging technique that maps the shape and curvature of the corneal surface, used to diagnose conditions like keratoconus and to plan refractive surgery.

A cataract surgery technique that uses ultrasound energy to emulsify and remove the clouded lens through a small incision, often with implantation of an intraocular lens.

An artificial lens implanted during cataract surgery to replace the natural crystalline lens and restore optical power, available in monofocal, multifocal, and toric designs.

A common late complication of cataract surgery in which residual lens epithelial cells proliferate on the posterior capsule, causing blurred vision treated with laser capsulotomy.

A procedure using a neodymium:YAG laser to create an opening in an opacified posterior lens capsule after cataract surgery, restoring a clear visual axis.

Laser-assisted in situ keratomileusis, a refractive surgery that creates a corneal flap with a microkeratome or femtosecond laser and then uses an excimer laser to reshape the stroma.

A refractive surgery that removes the corneal epithelium and uses an excimer laser to ablate stromal tissue, avoiding a flap and often chosen for thin corneas.

A chronic progressive optic neuropathy with characteristic visual field loss, typically associated with elevated intraocular pressure despite an open anterior chamber angle.

A form of glaucoma caused by obstruction of aqueous outflow due to narrowing or closure of the anterior chamber angle, which can be acute and sight-threatening.

The fluid pressure within the eye, maintained by the balance of aqueous humor production and drainage, and a major modifiable risk factor for glaucoma.

A technique using a special contact lens and slit lamp to visualize the anterior chamber angle, essential for diagnosing angle-closure glaucoma and assessing angle structures.

A surgical procedure for glaucoma that creates a new drainage pathway for aqueous humor from the anterior chamber to the subconjunctival space, lowering intraocular pressure.

Enlargement and deepening of the central cup of the optic nerve head, a hallmark of glaucomatous damage reflecting loss of retinal ganglion cell axons.

An area of reduced or absent vision in the visual field, often detected by perimetry, and characteristic patterns (e.g., arcuate scotoma) help diagnose and monitor glaucoma and neurologic disease.

Microvascular retinal damage caused by diabetes, classified as non-proliferative (hemorrhages, exudates) or proliferative (neovascularization), and a leading cause of vision loss.

Swelling of the macula due to fluid accumulation, often from leaky retinal vessels in diabetes or other conditions, causing central vision distortion and blurring.

A laser treatment that applies scatter burns to the peripheral retina to reduce VEGF production and induce regression of neovascularization in proliferative diabetic retinopathy.

A non-invasive imaging technique using light interference to produce high-resolution cross-sectional images of the retina, used to diagnose and monitor macular and optic nerve disorders.

Separation of the neurosensory retina from the underlying retinal pigment epithelium, often due to a retinal tear, leading to vision loss if not repaired promptly.

Bleeding into the vitreous cavity, commonly from proliferative diabetic retinopathy, retinal tears, or trauma, causing sudden floaters or vision loss.

A pupillary abnormality in which the pupil dilates when light is swung from the normal eye to the affected eye, indicating asymmetric optic nerve or severe retinal dysfunction.

Inflammation of the optic nerve, often demyelinating and associated with multiple sclerosis, presenting with unilateral vision loss, pain on eye movement, and an RAPD.

Optic disc swelling caused by elevated intracranial pressure, typically bilateral, and a sign of conditions such as intracranial mass, hemorrhage, or idiopathic intracranial hypertension.

Drooping of the upper eyelid, which can be congenital or acquired due to levator muscle dysfunction, aponeurotic defects, or nerve palsy, and may obstruct vision.

The amount of upper eyelid excursion measured from downgaze to upgaze, used to classify ptosis severity and guide surgical planning.

A serious infection of the orbital tissues, often spreading from the sinuses, presenting with fever, proptosis, pain, and restricted eye movement, requiring urgent antibiotics.

Forward displacement of the eyeball from the orbit, measured with exophthalmometry, and a sign of orbital mass, inflammation, or thyroid eye disease.

Misalignment of the eyes, where one eye deviates inward, outward, upward, or downward, which can lead to amblyopia and impaired binocular vision if untreated.

Reduced vision in one or both eyes due to abnormal visual development, often from strabismus, refractive error, or deprivation, and treatable if detected early.

A clinical test to detect strabismus by alternately covering each eye and observing movement of the uncovered eye to reveal a manifest or latent deviation.

Inflammation of the uveal tract (iris, ciliary body, choroid), classified by location as anterior, intermediate, posterior, or panuveitis, with many infectious and autoimmune causes.

A collection of white blood cells in the anterior chamber, appearing as a layered sediment, often indicating severe intraocular inflammation or infection.

A malignant intraocular tumor arising from retinal precursor cells, most common in young children, presenting with leukocoria or strabismus and requiring urgent treatment.

A white pupillary reflex, which is an abnormal sign in children that can indicate retinoblastoma, congenital cataract, or other serious ocular conditions.

A measure of central vision using a chart with letters of decreasing size, expressed as a fraction comparing the test distance to the distance at which a normal eye sees that line.

A mismatch between the eye's optical power and its length that causes blurred vision, including myopia, hyperopia, and astigmatism, correctable with glasses or contact lenses.