Eye Diseases

ischemia

a severe reduction in the blood supply to any part of the body

neoplasm

a new growth of different or abnormal tissue

symptoms

the changes in vision they experience and the pain or other effects they feel

signs

abnormal changes observed by the physician on examination of the patient

proptosis/exophthalmus

any increase in volume of the orbital contents, pushing the eyeball forward

unilateral proptosis

bulging of only one eye

edema

swelling from large amounts of fluid

orbital cellulitis

diffuse infection of tissues in the orbit, symptoms may include decreased vision and ocular pain

strabismus

when the extraocular muscles are not functioning properly or are not in good balance, the eyes can go out of alignment, may cause diplopia

exodeviation

outward deviation of the eye

esodeviation

inward deviation of the eye

tropia

deviation is continually manifest or visible

phoria

can be elicited by covering only one eye so that the brain’s ability to fuse the images is blocked

stereopsis

3-dimensional visual perception

suppression

the brain ignores the image of the deviating eye

amblyopia

decreased vision

nystagmus

a condition in which the eyes shift involuntarily in a rhythmic beating motion

null point

an abnormal head position patients adopt to slow down the nystagmus and to see better

lagophthalmos

a condition in which the globe is not completely covered when the eyelids are closed

basal cell carcinoma

the most common malignant eye tumor, characteristic appearance of a pit surrounded by raised “pearly” edges

keratoconjunctivitis sicca

dry eye syndrome; patients report irritation, blurred vision, and a foreign-body sensation

ophthalmia neonatorum

conjunctivitis occurring in the first thirty days of life

pinguecula

a small, benign, yellow-white mass of degenerated tissue of the bulbar conjunctiva

pterygium

a wedge-shaped growth of the bulbar conjunctiva, probably the result of chronic sun exposure

keratitis

inflammation of the cornea

corneal ulcer

can be produced by bacterial or fungal infection of lesions; the corneal epithelium becomes eroded and the cornea loses its transparency and develops a gray-white opacity that can obscure vision

hypopyon

white blood cells and pus accumulate in the anterior chamber

herpes simplex virus

the virus that produces cold sores can also lead to keratitis and corneal ulcer, produces symptoms similar to but less severe than those associated with bacterial or fungal ulcers, dendritic figure can be seen on the corneal surface with fluorescent dye

arcus senilis

the outer edge of the cornea gradually becomes opaque, vision is unaffected

keratoconus

the cornea thins and assumes the shape of a cone, seriously affects the vision

scleritis

inflammation of the sclera, may occur in patients with autoimmune diseases

episcleritis

inflammation of the layer overlying the sclera, may result from allergy

hyphema

blood may collect in the anterior chamber as the result of trauma or certain diseases

glaucoma

exists when intraocular pressure is too high for continues normal function of the eye, can eventually damage the optic nerve causing an irreversible visual field loss

neovascular glaucoma

a form of secondary glaucoma that occurs when the drainage angle is blocked with abnormal blood vessels

congenital glaucoma

a rare disease in infants due to a malformation of the anterior chamber angle

neovascularization of the iris

the abnormal growth of new blood vessels on the iris

anisocoria

pupils of unequal size

aphakia

absence of the crystalline lens, usually because of cataract extraction

pseudophakia

correction for more normal vision

floaters

the particles and vitreous collagen fibers that are seen by the patient as spots or cobwebs

endophthalmitis

infection of the vitreous and adjacent tissues by bacteria accidentally introduced through injury or surgery

posterior vitrectomy

surgical removal of the vitreous

retinal detachment

separation of the sensory layers of the retina from its blood supply and the underlying pigment layer

rhegmatogenous, exudative, tractional

three major mechanisms for retinal detachment

rhegmatogenous retinal detachment

liquid vitreous enters the subretinal space through a retinal tear or hole; patient may notice stars or flashes of light at one corner of the eye, a sensation of a curtain moving across the eye, peripheral field abnormalities, and a painless loss of vision

exudative retinal detachment

results from fluid collecting in the subretinal space as a result of abnormalities of the underlying retinal pigment epithelium, blood vessels, choroid, or sclera

tractional retinal detachment

results from scarring and tension on the retina by the fibrous tissue growth, often seen in proliferative diabetic retinopathy or after trauma to the retina

photocoagulation

“welding” with light from a laser

pneumatoretinopexy

injection of gas into the eye

scleral buckle

placing a band of silicone or other material on the eye to indent the wall

cryopexy

freezing the tissues of the eye in the location of the detachment to form a scar

diabetic retinopathy

the most common abnormality of the eye in patients with diabetes mellitus

retinal hemorrhages

dots or blots of blood within the retina

microaneurysms

balloonlike dilaiton of the vessels

macular edema

fluid collecting within the macula

dry AMD

characterized by drusen and atrophic spots

drusen

yellow-white deposits in the retinal pigment epithelium

wet AMD

characterized by leaking and bleeding from fragile new blood vessel growth underlying the macula

retinitis pigmentosa

one of the most common hereditary, progressive retinal diseases that results in severe bilateral peripheral vision loss, causes the rod photoreceptors within the retina to degenerate

nyctalopia

loss of vision in dim light

vascular occlusions

blockage of the blood vessels that serve the retina

optic neuropathies

disease processes affecting the function of the optic nerve

papilledema

swelling of the optic disc caused by engorged blood vessels, cotton-wool spots, and hemorrhages

optic neuritis

inflammation of the optic nerve; can produce sudden, painful, but reversible, loss of sight; may be due to infections or immune reactions

anterior ischemic optic neuropathy

occlusion of the blood supply to the optic nerve; can cause sudden severe vision loss