Sensory Problems of the Eye and Ear Flashcards

Vocabulary flashcards covering sensory problems of the eye and ear, including anatomy, refractive errors, infections, retinal/macular diseases, glaucoma, and hearing disorders.

Sclera

The white, dense connective tissue layer of the eye containing no blood vessels, whose clear front portion forms the cornea.

Choroid

The middle layer of the eye containing abundant blood vessels and pigment, which attaches to the iris to control pupil size.

Retina

The innermost sensory layer of the eye that transforms light waves into nerve impulses.

Anterior Chamber

The fluid-filled space in front of the lens containing aqueous humor produced by the ciliary body.

Canal of Schlemm

The drainage structure in the eye through which aqueous humor exits after passing through the trabecular meshwork.

Posterior Chamber

The space behind the lens that contains vitreous humor.

Miosis

Pupil constriction triggered by parasympathetic nervous system activation and contraction of the circular sphincter muscle in strong light.

Mydriasis

Pupil dilation triggered by sympathetic nervous system activation and contraction of the radial/dilator muscle in weak light.

Pinna

The funnel-shaped outer structure of the external ear that conducts sound waves to the tympanic membrane.

Auditory Ossicles

Three tiny bones in the middle ear (malleus, incus, stapes) that vibrate in response to the tympanic membrane to transmit sound to the oval window.

Eustachian Tube

The canal connecting the middle ear to the nasopharynx that equalizes pressure between the inner ear and outside atmosphere.

Organ of Corti

The sensory receptor organ for hearing located inside the cochlea.

Membranous Labyrinth

The system of fluid-filled structures in the inner ear containing semicircular canals that regulate movement and balance.

Refraction

The eye's ability to bend light rays so that they fall directly on the retina.

Myopia

Nearsightedness caused by excessive light refraction or an abnormally long eye, resulting in light focusing in front of the retina.

Hyperopia

Farsightedness where light rays focus behind the retina, requiring accommodation to focus near objects.

Presbyopia

The loss of ocular accommodation associated with aging.

Astigmatism

A refractive error caused by an uneven or irregular curvature of the cornea.

Legal Blindness

Defined as a visual acuity of $20/200$ or worse in the better eye with best correction.

Hordeolum

A small, superficial white nodule along the lid margin caused by a bacterial infection (usually Staphylococcus aureus) of a meibomian gland.

Chalazion

A chronic inflammatory granuloma of the meibomian gland that may evolve from a hordeolum or blocked gland rupture.

Conjunctivitis

Infection or inflammation of the conjunctiva (pink eye) caused by bacteria, viruses, allergens, or chemical irritants.

Trachoma

A major cause of blindness worldwide caused by Chlamydia, transmitted by hands or flies, leading to mucopurulent discharge and lid swelling.

Keratitis

Inflammation or infection of the cornea, for which contact lens wear is a major risk factor.

Corneal Ulcer

Tissue loss caused by corneal infection resulting in pain, photophobia, discharge, and potential permanent vision loss.

Keratoconjunctivitis Sicca

Dry eye disorder caused by a decrease in tear film quality or quantity, commonly linked to aging and autoimmune conditions like Sjögren's.

Cataracts

Opacity or clouding of the lens leading to gradual, painless visual impairment and light glare.

Diabetic Retinopathy

A process of microvascular damage to the retina occurring in patients with diabetes mellitus.

Nonproliferative Retinopathy

The most common form of diabetic retinopathy, marked by capillary microaneurysms, retinal swelling, hard exudates, and intraretinal dot/blot hemorrhages.

Proliferative Retinopathy

A severe form of diabetic retinopathy in which fragile, abnormal new blood vessels grow and leak blood, causing severe vision loss.

Hypertensive Retinopathy

Damage and blockages in retinal blood vessels caused by chronic high blood pressure.

Papilledema

Swelling of the optic disc and nerve resulting from sustained, severe hypertension.

Retinal Detachment

Separation of the sensory retina from the underlying pigment epithelium with fluid accumulation between the two layers.

Retinal Breaks

Interruptions in the full thickness of retinal tissue, classified as spontaneous atrophic holes or tractional tears from vitreous shrinkage.

Age-Related Macular Degeneration

A progressive eye disease affecting the macula, representing the most common cause of irreversible central vision loss in Americans over age $60$.

Drusen

Yellowish extracellular deposits that abnormally accumulate in the retinal pigment epithelium in dry macular degeneration.

Metamorphopsia

A visual distortion where straight lines appear bent or wavy, commonly occurring in macular degeneration.

Glaucoma

A group of disorders characterized by elevated intraocular pressure, optic nerve atrophy, and peripheral visual field loss.

Primary Open-Angle Glaucoma

The most common form of glaucoma, developing slowly and painlessly with gradual peripheral vision loss leading to tunnel vision.

Acute Angle-Closure Glaucoma

A medical emergency caused by pupil dilation blocking aqueous humor outflow, resulting in sudden severe eye pain, halos around lights, and nausea.

Nasolacrimal Pressure

The application of pressure to the inner corner of the eye for $2\text{ minutes}$ during drop instillation to prevent systemic drug absorption.

Timolol

A non-selective beta-blocker prototype (Timoptic) used in glaucoma to lower intraocular pressure by decreasing aqueous humor production.

Brimonidine

An alpha2-adrenergic agonist (Alphagan) used for open-angle glaucoma that decreases aqueous humor production.

Latanoprost

A prostaglandin analog (Xalatan) that increases aqueous humor outflow to treat glaucoma, known to cause brown iris pigmentation.

Presbycusis

Age-related sensorineural hearing loss causing difficulty hearing high-pitched sounds and understanding speech in background noise.

Conductive Hearing Loss

Hearing impairment resulting from obstruction of sound transmission in the outer or middle ear, such as impacted cerumen or otosclerosis.

Sensorineural Hearing Loss

Hearing loss caused by damage to the inner ear (cochlea), auditory nerve, or central auditory pathways.

Meniere's Disease

A progressive inner ear disorder caused by endolymph accumulation in the membranous labyrinth, causing episodic vertigo, tinnitus, and hearing loss.

Tinnitus

A perception of ringing or roaring sounds in the ear associated with inner ear or auditory nerve disorders.

Vertigo

An illusion of motion or spinning sensation caused by vestibular dysfunction, often accompanied by nausea and vomiting.