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Chapter 11...

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Chapter 11 Major Structures

Relat Relate ed Combining F Forms orms

Primary Functions

Major Structures

Relat Relate ed Combining F Forms orms

Primary Functions

Eyes

opt/i , opt/o , optic/o , ophthalm/o

Receptor organs for the sense of sight.

Iris

ir/i , ir/o , irid/o , irit/o

Controls the amount of light entering the eye.

Lens

phac/o , phak/o

Focuses rays of light on the retina.

Retina

re retin/o tin/o

Converts light images into electrical impulses and transmits them to the brain.

Lacrimal Apparatus

dacryocyst/o , lacrim/o

Accessory structures of the eyes that produce, store, and remove tears.

Ears

acous/o , acoust/o , audi/o , audit/o , ot ot/o /o

Receptor organs for the sense of hearing; also help maintain balance.

Outer Ear

pinn/i

Transmits sound waves to the middle ear.

Middle Ear

myring/o , tympan/o

Transmits sound waves to the inner ear.

Inner Ear

labyrinth/o

Receives sound vibrations and transmits them to the brain.

Word Parts  blephar/o eyelid  -cusis hearing  irid/o iris, colored part of eye  kerat/o horny, hard, cornea  myring/o tympanic membrane, eardrum  ophthalm/o eye, vision  -opia vision condition  opt/o eye, vision  ot/o ear, hearing  phak/o lens of eye  presby/o old age  retin/o retina, net

  

scler/o sclera, white of eye, hard trop/o turn, change tympan/o tympanic membrane, eardrum

adnexa The appendages or accessory structures of an organ. In the eye, these are the structures outside the eyeball, including the orbit, eye muscles, eyelids, eyelashes, conjunctiva, and lacrimal apparatus. Amblyopia Dimness of vision or the partial loss of sight, especially in one eye, without detectable disease of the eye. Ametropia Any error of refraction in which images do not focus properly on the retina. Anisocoria A condition in which the pupils are unequal in size. Astigmatism A condition in which the eye does not focus properly because of uneven curvatures of the cornea. Audiometry The use of an audiometer to measure hearing acuity. Cataract The loss of transparency of the lens of the eye that causes a progressive loss of visual clarity. Chalazion A nodule or cyst, usually on the upper eyelid, caused by obstruction in a sebaceous gland. cochlear implant An electronic device that bypasses the damaged portions of the ear and directly stimulates the auditory nerve. Conjunctivitis Inflammation of the conjunctiva, usually caused by an infection or allergy; also known as pinkeye. Dacryoadenitis An inflammation of the lacrimal gland that can be a bacterial, viral, or fungal infection. Diplopia The perception of two images of a single object; also known as double vision. Ectropion The eversion (turning outward) of the edge of an eyelid. Emmetropia The normal relationship between the refractive power of the eye and the shape of the eye that that enables light rays to focus correctly on the retina. Entropion The inversion (turning inward) of the edge of an eyelid.

Esotropia Strabismus characterized by an inward deviation of one eye or both eyes; also known as cross-eyes Exotropia Strabismus characterized by the outward deviation of one eye relative to the other; also known as walleye. fluorescein angiographyA photographic study of the blood vessels in the back of the eye following the intravenous injection of a fluorescein dye that acts as a contrast medium. Glaucoma A group of eye diseases characterized by increased intraocular pressure (IOP) that causes damage to the optic nerve and retinal nerve fibers. Hemianopia Blindness in one-half of the visual field. Hordeolum A pus-filled and often painful lesion on the eyelid resulting from an infection in a sebaceous gland; also known as a stye. Hyperopia A vision defect in which light rays focus beyond the retina; also known as farsightedness. infectious myringitis A contagious inflammation associated with a middle-ear infection that causes painful blisters on the eardrum. Iridectomy The surgical removal of a portion of the iris tissue. Iritis Inflammation of the uvea affecting primarily structures in the front of the eye. Keratitis Inflammation of the cornea. Labyrinthectomy The surgical removal of all or a portion of the labyrinth of the inner ear. laser trabeculoplasty Treatment of open-angle glaucoma in which a laser is used to create an opening in the trabecular meshwork to allow fluid to drain properly. Mastoidectomy The surgical removal of mastoid cells. Mydriasis The dilation of the pupil. Myopia A vision defect in which light rays focus in front of the retina; also known as nearsightedness. Myringotomy A small surgical incision into the eardrum to relieve pressure from excess pus or fluid or to create an opening for the placement of ear tubes. Nyctalopia A condition in which an individual with normal daytime vision has difficulty seeing at night; also known as night blindness.

Nystagmus Involuntary, constant, rhythmic movement of the eyeball. Ophthalmoscopy The visual examination of the fundus (back part) of the eye with an ophthalmoscope; also known as funduscopy Optometrist A specialist who holds a Doctor of Optometry degree and provides primary eye care, including diagnosing eye diseases and conditions and measuring the accuracy of vision to determine if corrective lenses are needed. otitis media Inflammation of the middle ear. Otomycosis A fungal infection of the external auditory canal; also known as swimmer's ear. Otopyorrhea The flow of pus from the ear. Otorrhea Any discharge from the ear. Otosclerosis Ankylosis of the bones of the middle ear, resulting in a conductive hearing loss. Papilledema Swelling and inflammation of the optic nerve at the point of entrance into the eye through the optic disk; also known as choked disk. periorbital edema Swelling of the tissues surrounding the eye or eyes. Photophobia Excessive sensitivity to light. Presbycusis A gradual sensorineural hearing loss that occurs as the body ages. Presbyopia Decline of near vision that occurs with age as the lens becomes less flexible and the muscles of the ciliary body become weaker. Ptosis Drooping of the upper eyelid that is usually due to paralysis. radial keratotomy A surgical procedure to treat myopia. Retinopexy Treatment to reattach the detached area in a retinal detachment Scleritis Inflammation of the sclera of the eye. sensorineural hearing loss Deafness that develops when the auditory nerve or hair cells in the inner ear are damaged. Stapedectomy The surgical removal of part of the stapes bone and its replacement with a small prosthetic device.

Strabismus A disorder in which the eyes point in different directions or are not aligned correctly because the eye muscles are unable to focus. Tarsorrhaphy The partial or complete suturing together of the upper and lower eyelids. Tinnitus A ringing, buzzing, or roaring sound in one or both ears. Tonometry The part of a routine eye examination in which intraocular pressure (IOP) is measured. Tympanometry The use of air pressure in the ear canal to test for disorders of the middle ear. Vertigo A sense of whirling, dizziness, and the loss of balance, often combined with nausea and vomiting. Vitrectomy The removal of the vitreous fluid of the posterior chamber of the eye and its replacement with a clear solution. Xerophthalmia Drying of the eye surfaces, including the conjunctiva; also known as dry eye.

The eye lids o Ptosis is the drooping of the upper eyelid that is usually due to paralysis o ptosis means drooping or sagging  The term blepharoptosis has the same meaning. o A chalazion is a nodule or cyst, usually on the upper eyelid, caused by obstruction in a sebaceous gland. The plural of chalazion is chalazia. A chalazion is a type of granuloma. Compare with a hordeolum. o A hordeolum, also known as a stye, is a pus-filled and often painful lesion on the eyelid resulting from an acute infection in a sebaceous gland. Compare with a chalazion. o Blepharitis is swelling of the eyelid, often at the location of the eyelash hair follicles. o blephar means eyelid, and -itis means inflammation o Ectropion is the eversion of the edge of an eyelid o ec- means out, trop means turn, and -ion means condition  Eversion means turning outward. This usually affects the lower lid, thereby exposing the inner surface of the eyelid to irritation and preventing tears from draining properly Ectropion is the opposite of entropion. o Entropion is the inversion of the edge of an eyelid o en- means in, trop means turn, and -ion means condition  Inversion means turning inward. This usually affects the lower eyelid and causes the eyelashes to rub against the cornea. Entropion is the opposite of ectropion. o Periorbital edema is swelling of the tissues surrounding the eye or eyes o peri- means surrounding, orbit means eyeball, and -al means pertaining to  This can give the face a bloated appearance and cause the eyes to be partially covered by the swollen eyelids. This swelling is associated with conditions such as allergic reaction, nephrotic syndrome, or cellulitis.

Additional Adnexa Pathology o Conjunctivitis, also known as pinkeye, is an inflammation of the conjunctiva that is usually caused by an infection or allergy o conjunctiv means conjunctiva, and -itis means inflammation o Dacryoadenitis is an inflammation of the lacrimal gland caused by a bacterial, viral, or fungal infection o dacry/o means tear, aden means gland, and -itis means inflammation  Signs and symptoms of this condition include sudden severe pain, redness, and pressure in the orbit of the eye. o Subconjunctival hemorrhage is bleeding between the conjunctiva and the sclera. This condition, which is usually caused by an injury, creates a red area over the white of the eye.

o Xerophthalmia, also known as dry eye , is drying of eye surfaces, including the conjunctiva, because the tear glands do not produce enough tears o xer means dry, ophthalm means eye, and -ia means abnormal condition  This condition is often associated with aging. It can also be due to systemic diseases such as rheumatoid arthritis or caused by a lack of vitamin A.  Uvea, Cornea, Iris, and Sclera o Uveitis is an inflammation of the uvea causing swelling and irritation o uve means uvea, and -itis means inflammation  Complications from uveitis can potentially lead to permanent vision loss. o Iritis is the most common form of uveitis. This inflammation of the uvea affects primarily structures in the front of the eye o ir means iris, and -itis means inflammation  This condition has a sudden onset and may last six to eight weeks. o A corneal abrasion is an injury, such as a scratch or irritation, to the outer layers of the cornea o corne means cornea, and -al means pertaining to  Compare with corneal ulcer. o A corneal ulcer is a pitting of the cornea caused by an infection or injury. Although these ulcers heal with treatment, they can leave a cloudy scar that impairs vision. Compare with corneal abrasion. o Diabetic retinopathy is damage to the retina as a complication of uncontrolled diabetes. As diabetic retinopathy progresses, diabetic macular edema can occur. o Keratitis is an inflammation of the cornea o kerat means cornea, and -itis means inflammation  This condition can be due to many causes, including bacterial, viral, or fungal infections. Note: kerat/o also means hard. o Keratoconus occurs when the cornea becomes irregular and cone-shaped, causing blurring and distortion of vision. o Scleritis is an inflammation of the sclera o scler means white of the eye, and -itis means inflammation  This condition is usually associated with infections, chemical injuries, or autoimmune diseases.

The Eye o Anisocoria is a condition in which the pupils are unequal in size o anis/o means unequal, cor means pupil, and -ia means abnormal condition  This condition can be congenital or caused by a head injury, an aneurysm, or pathology of the central nervous system. o A cataract is the loss of transparency of the lens that causes a progressive loss of visual clarity. The formation of most cataracts is associated with aging; however, this condition can be congenital or due to an injury or disease

o Floaters, also known as vitreous floaters, are particles of cellular debris that float in the vitreous humor and cast shadows on the retina. Floaters often occur normally but may be an indication of retinal detachment, especially when accompanied by photopsia. o Photopsia is the presence of what appears to be flashes of light, or flashers o phot means light, and -opsia means view of  These are often caused by damage to the eye or migraine headaches. o Miosis is the contraction of the pupil, normally in response to exposure to light but also possibly due to the use of prescription or illegal drugs o mio- means smaller, and -sis means abnormal condition o Mydriasis, the dilation of the pupil, is the opposite of miosis o mydrias means the dilation of the pupil, and -is means abnormal condition  The causes of mydriasis include diseases, trauma (injury), and drugs. o Nystagmus is an involuntary, constant, rhythmic movement of the eyeball that can be congenital or caused by a neurological injury or drug use. o Papilledema, also known as choked disk, is swelling and inflammation of the optic nerve at the point of entrance into the eye through the optic disk o papill means nipple-like, and -edema means swelling.  This swelling is caused by increased intracranial pressure and can be due to a tumor pressing on the optic nerve. o Retinal detachment, also known as a detached retina, and retinal tears are the separation of some or all of the light-sensitive retina from the choroid. If not treated, the entire retina can detach, causing blindness. These conditions can be caused by head trauma, aging, or the vitreous humor separating from the retina

o Retinitis pigmentosa is a progressive degeneration of the retina that affects night and peripheral vision. It can be detected by the presence of dark pigmented spots in the retina. o Temporal arteritis is a form of vasculitis that can cause a sudden vision loss, usually in one eye Glaucoma Glaucoma is a group of diseases characterized by increased intraocular pressure that causes damage to the retinal nerve fibers and the optic nerve. This increase in pressure is caused by a blockage in the flow of fluid out of the eye. If untreated, this pressure can cause the loss of peripheral vision and eventually blindness. • Open-angle glaucoma, also known as chronic glaucoma, is by far the most common form of this condition. The trabecular meshwork gradually becomes blocked, causing a buildup of pressure. Symptoms of this condition are not noticed by the patient until the optic nerve has been damaged; however, it can be detected earlier through regular eye examinations, including tonometry and visual field testing. See the later section “Diagnostic Procedures for Vision and the Eyes.”

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In closed-angle glaucoma, also known as acute glaucoma, the opening between the cornea and iris narrows so that fluid cannot reach the trabecular meshwork. This narrowing can cause a sudden increase in the intraocular pressure that produces severe pain, nausea, redness of the eye, and blurred vision. Without immediate treatment, blindness can occur in as little as two days. Macular Degeneration Macular degeneration (MD) is a gradually progressive condition in which the macula at the center of the retina is damaged, resulting in the loss of central vision but not in total blindness.  macul means spot, and -ar mean pertaining to • Age-related macular degeneration occurs most frequently in older people and is the leading cause of severe vision loss in those over 60. • Dry macular degeneration, which accounts for 90% of all AMD cases, is caused by the slow deterioration of the cells of the macula.  Wet macular degeneration is an advanced form of dry AMD. New blood vessels growing beneath the retina leak blood and fluid, damaging the retinal cells. These small hemorrhages usually result in rapid and severe vision loss. Functional Defects o Diplopia, also known as double vision, is the perception of two images of a single object o dipl means double, and -opia means vision condition  It is sometimes a symptom of a serious underlying disorder such as multiple sclerosis or a brain tumor. o Hemianopia is blindness in one-half of the visual field o hemi- means half, an- means without, and -opia means vision condition o Monochromatism also known as color blindness, is the inability to distinguish certain colors in a normal manner o mon/o means one, chromat means color, and -ism means condition  This is a genetic condition caused by deficiencies in or the absence of certain types of cones in the retina. o Nyctalopia, also known as night blindness, is a condition in which an individual with normal daytime vision has difficulty seeing at night o nyctal means night, and -opia means vision condition o Photophobia means excessive sensitivity to light and can be the result of migraines, excessive wearing of contact lenses, drug use, or inflammation o phot/o means light, and -phobia means abnormal fear o Presbyopia is the condition of common changes in the eyes that occur with aging o presby means old age, and -opia means vision condition  With age, near vision declines noticeably as the lens becomes less flexible and the muscles of the ciliary body become weaker. The result is that the eyes are no longer able to focus the image properly on the retina. Strabismus Strabismus is a disorder in which the eyes point in different directions or are not aligned correctly, because the eye muscles are unable to focus together.

o Esotropia, also known as cross-eyes, is strabismus characterized by an inward deviation of one or both eyes o eso- means inward, trop means turn, and -ia means abnormal condition. Esotropia is the opposite of exotropia. o Exotropia, also known as walleye, is strabismus characterized by the outward deviation of one eye relative to the other o exo- means outward, trop means turn, and -ia means abnormal condition Exotropia is the opposite of esotropia. A refractive disorder is a focusing problem that occurs when the lens and cornea do not bend light so that it focuses properly on the retina Refraction. (A) Normal vision. (B) Hyperopia. (C) Myopia.

Ametropia is any error of refraction in which images do not focus properly on the retina. o ametr means out of proportion, and -opia means vision condition  Astigmatism, hyperopia, and myopia are all forms of ametropia. o Astigmatism is a condition in which the eye does not focus properly because of uneven curvatures of the cornea. o Hyperopia, also known as farsightedness, is a defect in which light rays focus beyond the retina o hyper- means excessive, and -opia means vision condition  This condition can occur in childhood but usually causes difficulty after age 40. Hyperopia is the opposite of myopia. o Myopia, also known as nearsightedness, is a defect in which light rays focus in front of the retina o my is from the Greek word for shortsighted, and -opia means vision condition  This condition occurs most commonly around puberty. Myopia is the opposite of hyperopia. Blindness Blindness is the inability to see. Although some sight remains, legal blindness is the point at which, under law, an individual is considered to be blind. A commonly used standard is that a person is legally blind when his or her best-corrected vision is reduced to 20/200 or less. o

Amblyopia is a dimness of vision or the partial loss of sight, especially in one eye, without detectable disease of the eye o ambly means dim or dull, and -opia means vision condition o Scotoma also known as blind spot, ...