1. Chapter 17
Objectives
Identify locations and functions of the major parts of the eye and ear.
Name the combining forms, prefixes, and suffixes most commonly used to describe these organs and their parts.
Describe the abnormal conditions that may affect the eye and ear.
Identify clinical procedures that pertain to ophthalmology and otology.
Apply your new knowledge to understanding medical terms in their proper contexts, such as medical reports and records.

2. Sense Organs: The Eye & The Ear
Chapter 17
Pages 697 – 748

3. Vocabulary – The Eye Pages 702 – 703 accommodation cornea optic nerve
anterior chamber
fovea centralis
pupil
fundus of the eye
refraction
aqueous humor
retina
biconvex
iris
rod
choroid
lens
sclera
ciliary body
macula
thalamus
cone
optic chiasm
vitreous humor
conjunctiva
optic disc
ACCOMMODATION (ă-kŏm-ō-DĀ-shŭn) Normal adjustment of the eye to focus on objects. When the eye focuses from far to near, the ciliary body adjusts the lens (rounding it) and the pupil constricts. When the eye focuses from near to far, the ciliary body flattens the lens and the pupil dilates.
ANTERIOR CHAMBER (ăn-TĒ-rē-ŏr CHĀM-bĕr) Space behind the cornea and in front of the lens and iris; contains aqueous humor.
AQUEOUS HUMOR (ĂK-wē-ŭs or Ā-kwē-ŭs HŪ-mĕr) Fluid produced by the ciliary body and found in the anterior chamber of the eye. A humor [Latin humidusmeans moist] is any body fluid, including blood and lymph.
BICONVEX (bī-KŎN-vĕks) Consisting of two surfaces that are rounded, elevated, and curved evenly, like part of a sphere. The lens of the eye is a biconvex body.
CHOROID (KŎR-oyd) Middle, vascular layer of the eye, between the retina and the sclera
CILIARY BODY (SĬL-ē-ăr-ē BŎD-ē) Structure on each side of the lens that connects the choroid and iris; contains ciliary muscles that control the shape of the lens, and it secretes aqueous humor
CONE (kōn) Photoreceptor cell in the retina that transforms light energy into a nerve impulse; responsible for color and central vision
CONJUNCTIVA (kŏn-jŭnk-TĪ-vă) Delicate membrane lining the eyelids and covering the eyeball
CORNEA (KŎR-nē-ă) Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball
FOVEA CENTRALIS (FŌ-vē-ă sĕn-TRĂ-lĭs) Tiny pit or depression in the retina that is the region of clearest vision
FUNDUS OF THE EYE (FŬN-dŭs) Large, posterior inner part of the eye that is visualized with an ophthalmoscope
IRIS (Ī-rĭs) Colored, pigmented portion of the eye; surrounds the pupil
LENS (lĕnz) Transparent biconvex body behind the pupil of the eye; bends (refracts) light rays to bring them into focus on the retina
MACULA (MĂK-ū-lă) Yellowish region on the retina lateral to and slightly below the optic disc; contains the fovea centralis [area of clearest vision]
OPTIC CHIASM (ŎP-tĭk KĪ-ăzm) Point at which optic nerve fibers cross in the brain
OPTIC DISC (ŎP-tĭk dĭsk) Region at the back of the eye where the optic nerve meets the retina; the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light
OPTIC NERVE (ŎP-tĭk nĕrv) Cranial nerve that carries impulses from the rod and cone cells of the retina to the cerebral cortex in the occipital lobe of the brain
PUPIL (PŪ-pĭl) Dark, central portion of the eye, surrounded by the iris, through which light rays pass
REFRACTION (rē-FRĂK-shŭn) Bending of light rays by the cornea, lens, and fluids of the eye to bring the rays into focus on the retina
RETINA (RĔT-ĭ-nă) Light-sensitive nerve cell layer of the eye containing photoreceptor cells [rods and cones].
ROD (rŏd) Photoreceptor retinal cell; essential for seeing objects in low light and for peripheral vision
SCLERA (SKLĔ-ră) Tough, white outer coat of the eyeball.
THALAMUS (THĂL-ă-mŭs) Relay center in the brain through which optic nerve fibers pass on their way to the cerebral cortex
VITREOUS HUMOR (VĬT-rē-ŭs HŪ-mŏr) Soft, jelly-like material behind the lens in the vitreous chamber; helps maintain the shape of the eyeball

4. Combining Forms Pages 704 – 705
Meaning Example
aque/o blephar/o, palpebr/o conjunctiv/o cor/o, pupill/o corne/o, kerat/o cycl/o dacry/o, lacrim/o
water
eyelid
conjunctiva
pupil
cornea
ciliary body
tears, tear duct
aqueous humor
blepharitis, blepharoptosis, palpebral
conjunctivitis
anisocoria, pupillary
corneal abrasion, keratitis
cycloplegic
dacryoadenitis, lacrimal, lacrimation
COMBINING FORMS THAT HAVE TO DO WITH STRUCTURES AND FLUIDS
AQUEOUS HUMOR (ĂK-wē-ŭs or Ā-kwē-ŭs HŪ-mĕr) Fluid produced by the ciliary body and found in the anterior chamber of the eye. A humor [Latin humidusmeans moist] is any body fluid, including blood and lymph.
BLEPHARITIS (blĕf-ă-RĪ-tĭs) Inflammation of an eyelid, causing redness, crusting, and swelling along lid margins – See Figure 17-6A. BLEPHAROPTOSIS (blĕf-ă-rŏp-TŌ-sĭs) Prolapse of the upper eyelid
ETIOLOGY: abnormalities of the eyelid muscle or by nerve damage
PALPEBRAL (PĂL-pĕ-brăl) Pertaining to an eyelid
CONJUNCTIVITIS (kŏn-jŭnk-tĭ-VĪ-tĭs) Inflammation of the conjunctiva; Also known as pinkeye (Figure 17-6B).
SYMPTOM: blood vessels dilate
ETIOLOGY: allergens like pollen (allergic conjunctivitis), bacterial infection (bacterial conjunctivitis), or virus (viral conjunctivitis).
ANISOCORIA (ăn-ī-sō-KŌ-rē-ă) Inequality in the size of pupils; may indication of neurologic injury or disease (Figure 17-7A).
PUPILLARY (PŪ-pĭ-lăr-ē) Pertaining to the pupil of the eye
CORNEAL ABRASION (KŎR-nē-ăl ă-BRĀ-zhŭn) Rubbing off of a part of the outer layer of the cornea
KERATITIS (kĕr-ă-TĪ-tĭs) Inflammation of the cornea
CYCLOPLEGIC (sī-klō-PLĒ-jĭk) Paralysis of the muscles of the ciliary body
DACRYOADENITIS (dăk-rē-ō-ăd-ĕ-NĪ-tĭs) Inflammation of tear glands (Figure 17-7B shows the lacrimal gland and lacrimal ducts.)
LACRIMAL (LĂK-rĭ-măl) Pertaining to tears
LACRIMATION (lă-krĭ-MĀ-shŭn) Production of tears

5. Combining Forms (cont’d)
Pages 705 – 706
Combining Forms (cont’d)
Meaning Example
ir/o, irid/o ocul/o, ophthalm/o opt/o, optic/o papill/o phac/o, phak/o
iris
eye
eye, vision
optic disc; nipple-like
lens of the eye
iritis, iridic, iridectomy
intraocular, ophthalmologist, ophthalmic, ophthalmoplegia
optic, optometrist, optician
papilledema
phacoemulsification, aphakia
IRITIS (ī-RĪ-tĭs) Inflammation of the iris of the eye
SYMPTOM: pain, sensitivity to light, and lacrimation [Production of tears].
TREATMENT: corticosteroid [reduce inflammation] IRIDIC (ĭ-RĪD-ĭk) Pertaining to the iris
IRIDECTOMY (ĭr-ĭ-DĔK-tō-mē) Removal of a portion of the iris to improve drainage of aqueous humor or to extract a foreign body.
INTRAOCULAR (ĭn-tră-ŎK-ū-lăr) Pertaining to within the eye
OPHTHALMOLOGIST (ŏf-thăl-MŎL-ō-jĭst) Medical doctor specializing in treating diseases and disorders of the eye
OPHTHALMIC (ŏf-THĂL-mĭk) Pertaining to the eye
OPHTHALMOPLEGIA (ŏf-thăl-mō-PLĒ-jă) Paralysis of muscles that move the eyeball
OPTIC (ŏp-tĭc) of or relating to vision or the eye
OPTOMETRIST (ŏp-TŎM-ĕ-trĭst) Non-medical professional trained to examine and measure the eye to prescribe and fit eyeglasses and contact lenses; a doctor of optometry (O.D.). OPTICIAN (ŏp-TĬSH-ăn) Non-medical professional trained in grinding lenses and fitting eyeglasses but cannot prescribe lenses.
PAPILLEDEMA (păp-ĕ-lĕ-DĒ-mă) Swelling of the optic disc; associated with increased intracranial pressure and hyperemia [increased blood flow] in the region of the optic disc.
PHACOEMULSIFICATION (făk-ō-ĕ-mŭl-sĭ-fĭ-KĀ-shŭn) A technique of cataract extraction using ultrasonic vibrations break up the lens; the pieces are then aspirated through the ultrasonic probe. In most patients, a foldable intraocular lens (IOL) is implanted at the time of surgery. (Figure 17-19)
APHAKIA (ă-FĀ-kē-ă) Absence of the lens of the eye
ETIOLOGY: may be congenital, but most often it is the result of extraction of a cataract [clouded lens] without placement of an artificial lens [pseudophakia].

6. Combining Forms (cont’d)
Pages 706 – 707
Combining Forms (cont’d)
Meaning Example
retin/o scler/o uve/o vitre/o
retina
sclera (white of the eye); hard
uvea
glassy
retinitis, hypertensive retinopathy
corneoscleral, scleritis
uveitis
vitreous humor
RETINITIS (rĕt-ĭ-NĪ-tĭs) Inflammation of the retina.
EXAMPLE: RETINITIS PIGMENTOSA (rĕt-ĭ-NĪ-tĭs pĭg-mĕn-TŌ-să) Inflammation of the retina with pigmentation and progressive scarring of tissue [destruction of rods]
ETIOLOGY: genetic disorder
SYMPTOM: Decreased vision and night blindness [nyctalopia]. HYPERTENSIVE RETINOPATHY (hī-pĕr-TĔN-sĭv rĕ-tĭ-NŎP-ă-thē) Disease of the retina due to high blood pressure; Lesions such as narrowing of arterioles, microaneurysms, hemorrhages, and exudates (fluid leakage) are found on examination of the fundus.
CORNEOSCLERAL (kŏr-nē-ō-SKLĔ-răl) Pertaining to the cornea and sclera, which is the white of the eye
SCLERITIS (sklĕ-RĪ-tĭs) Inflammation of the sclera
UVEITIS (ū-vē-Ī-tĭs) Inflammation of the uvea [iris, choroids, and ciliary body], which is the vascular layer of the eye
VITREOUS HUMOR (VĬT-rē-ŭs HŪ-mŏr) Soft, jelly-like material behind the lens in the vitreous chamber; helps maintain the shape of the eyeball

7. Combining Forms (cont’d)
Page 707
Combining Forms (cont’d)
Meaning Example
ambly/o dipl/o glauc/o mi/o mydr/o nyct/o phot/o presby/o scot/o xer/o
dull, dim
double
gray
smaller, less
widen, enlarge
night
light
old age
darkness
dry
amblyopia
diplopia
glaucoma
miosis
mydriasis
nyctalopia
photophobia
presbyopia
scotoma
xerophthalmia
COMBINING FORMS THAT HAVE TO DO WITH CONDITIONS
AMBLYOPIA (ăm-blē-Ō-pē-ă) Reduced vision [poor eyesight]; can be a unilateral or bilateral reduction of visual acuity. Early in life (before age 7 to 10) ocular misalignment, such as with strabismus, uncorrected errors of refraction, or other eye disorders, can lead to amblyopia –also known as lazy eye.
DIPLOPIA (dĭp-LŌ-pē-ă) Double vision
GLAUCOMA (glaw-KŌ-mă) Increased intraocular pressure because of the inability of aqueous humor to drain from the eye and enter the bloodstream. (Figure 17-10)
Normally, aqueous humor is formed by the ciliary body, flows into the anterior chamber, and leaves the eye at the angle where the cornea and the iris meet.
COMPLICATION: damage to the retina and optic nerve with loss of vision.
DIAGNOSED: tonometry with an instrument applied externally to the eye after administration of local anesthetic.
EXAMPLE:
Acute glaucoma = extreme ocular pain, blurred vision, redness of the eye, and dilation of the pupil. If untreated→ blindness.
Chronic glaucoma = no symptoms initially.
SYMPTOM: may experience a gradual loss of peripheral vision, with headaches, blurred vision, and halos around bright lights, or they may experience no symptoms at all.
TREATMENT: Administration of drugs to lower intraocular pressure. Sometimes, laser therapy is used to treat narrow-angle glaucoma by creating a hole in the periphery of the iris (iridotomy), which allows aqueous humor to flow more easily out of the anterior chamber and reduces intraocular pressure. 
EXAMPLES OF LASER THERAPY: Trabeculoplasty   (laser therapy) for chronic open-angle glaucoma causes scarring in the drainage angle, improving aqueous humor outflow and reducing intraocular pressure. Argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT) are used. SLT, which is as effective as ALT, uses a lower power laser and may be repeated, because the lower level of energy should cause less scarring.
MIOSIS (mī-Ō-sĭs) Contraction of the pupil of the eye.
EXAMPLE: MIOTIC (mī-ŎT-ĭk) Drug that causes the pupil of the eye to contract [such as pilocarpine]
MYDRASIS (mĭ-DRĪ-ă-sĭs) Widening of the pupil of the eye
EXAMPLE: Tropicamide, atropine, and cocaine cause dilation, or enlargement, of pupils.
NYCTALOPIA (nĭk-tă-LŌ-pē-ă) Night blindness or difficult, poor vision at night but good vision on bright days.
ETIOLOGY: Deficiency of vitamin A
PHOTOPHOBIA (fō-tō-FŌ-bē-ă) Sensitivity to light
PRESBYOPIA (prĕz-bē-Ō-pē-ă) Impairment of vision associated with middle or older age. With increasing age, loss of elasticity of the ciliary body impairs its ability to adjust the lens for accommodation to near vision. The lens of the eye cannot thicken to bend the rays coming from near objects (less than 20 feet away). The light rays focus behind the retina, as in hyperopia.
TREATMENT: a convex lens is needed to refract the rays coming from objects closer than 20 feet.
SCOTOMA (skō-TŌ-mă) Blind spot in the field of vision
ETIOLOGY: damage to the retina or the optic nerve.
XEROPHTHALMIA (zĕr-ŏf-THĂL-mē-ă) Condition of excessive dryness of the eye

8. Suffixes Page 708 -opia, -opsia -tropia vision to turn
Meaning Example
-opia, -opsia -tropia
vision
to turn
hyperopia, hemianopsia
esotropia, exotropia
HYPEROPIA (hī-pĕr-Ō-pē-ă) light rays are focused beyond, instead of directly on the retina; Also known as farsightedness or hypermetropia (Figure 17-8B) 
TREATMENT: A convex lens (thicker in the middle than at the sides) bends the rays inward before they reach the cornea, and thus the rays can be focused properly on the retina.
HEMIANOPSIA (hĕ-mē-ă-NŎP-sē-ă) Absence of vision for one half, right or left, of an individual's field of vision
ETIOLOGY: Stroke victims
ESOTROPIA (ĕs-ō-TRŌ-pē-ă) Turning inward of one or both pupils; Also known as cross-eyes
EXOTROPIA (ĕk-sō-TRŌ-pē-ă) Turning to the side or outward of one or both eyes
These conditions are examples of strabismus [defect in eye muscles so that both eyes cannot be focused on the same point at the same time].

9. Errors of Refraction Pages 708 – 709
ASTIGMATISM (ă-STĪG-mă-tĭzm) Defective curvature of the cornea or lens of the eye. This causes light rays to be unevenly and not sharply focused on the retina, so that the image is distorted.
TREATMENT: A cylindrical lens placed in the proper position in front of the eye can correct this problem (Figure 17-8A).
HYPEROPIA (hī-pĕr-Ō-pē-ă) light rays are focused beyond, instead of directly on the retina; Also known as farsightedness or hypermetropia (Figure 17-8B) 
TREATMENT: A convex lens (thicker in the middle than at the sides) bends the rays inward before they reach the cornea, and thus the rays can be focused properly on the retina.
MYOPIA (mī-Ō-pē-ă) Nearsightedness [vision for near objects is better than for far]; the eyeball is too long [front to back] or the refractive power of the lens so strong that light rays do not properly focus on the retina.
TREATMENT: Concave glasses (thicker at the periphery than in the middle) correct this condition because the lenses spread the rays out before they reach the cornea, so that they can be properly focused directly on the retina (Figure C).
PRESBYOPIA (prĕz-bē-Ō-pē-ă) Impairment of vision associated with middle or older age. With increasing age, loss of elasticity of the ciliary body impairs its ability to adjust the lens for accommodation to near vision. The lens of the eye cannot thicken to bend the rays coming from near objects (less than 20 feet away). The light rays focus behind the retina, as in hyperopia.
TREATMENT: a convex lens is needed to refract the rays coming from objects closer than 20 feet.

10. Pathology: Eye Pages 710 – 711 Cataract Chalazion Diabetic retinopathy
Glaucoma
CATARACT (KĂT-ă-răkt) The degenerative loss of transparency [Clouding] of the lens of the eye, causing a decreased in vision
ETIOLOGY: protein in the lens aggregates and clouds vision it is linked to the process of aging [senile cataracts]. Some cataracts, however, are present at birth, and others occur with diabetes mellitus, ocular trauma, and prolonged high-dose corticosteroid administration.
SYMPTOM: Vision appears blurred as the lens clouds over and becomes opaque.
TREATMENT: Surgical removal of the lens with implantation of an artificial lens behind the iris [the preferred position]. If an intraocular lens cannot be inserted, the patient may wear eyeglasses or contact lenses to help refraction.
PICTURE
CHALAZION (kă-LĀ-zē-ŏn) Small, hard mass [granuloma] formed around an inflamed sebaceous gland on the eyelid.
TREATMENT: often requires incision and drainage.
DIABETIC RETINOPATHY (dī-ă-BĔT-ĭk rĕ-tĭn-NŎP-ă-thē) Disease of the retina due to long-term effects of diabetes which include microaneurysms, hemorrhages, dilation of retinal veins, macular edema [fluid leaks from blood vessels into the retina], and neovascularization (new blood vessels form in the retina)
SYMPTOM: vision is blurred. Exudates (fluid leaking from the blood) appear in the retina as yellow-white spots.
TREATMENT: Laser photocoagulation [treats severe hemorrhaging on the retina], vitrectomy [treats vitreous jelly after hemorrhaging], injecting medications into the vitreous jelly [treats diabetic macular edema] and Corticosteroids [which promote regression of abnormal blood vessels, treats fluid leakage and neovascularization]
GLAUCOMA (glaw-KŌ-mă) Increased intraocular pressure because of the inability of aqueous humor to drain from the eye and enter the bloodstream. (Figure 17-10)
Normally, aqueous humor is formed by the ciliary body, flows into the anterior chamber, and leaves the eye at the angle where the cornea and the iris meet.
COMPLICATION: damage to the retina and optic nerve with loss of vision.
DIAGNOSED: tonometry with an instrument applied externally to the eye after administration of local anesthetic.
EXAMPLE:
Acute glaucoma = extreme ocular pain, blurred vision, redness of the eye, and dilation of the pupil. If untreated→ blindness.
Chronic glaucoma = no symptoms initially.
SYMPTOM: may experience a gradual loss of peripheral vision, with headaches, blurred vision, and halos around bright lights, or they may experience no symptoms at all.
TREATMENT: Administration of drugs to lower intraocular pressure. Sometimes, laser therapy is used to treat narrow-angle glaucoma by creating a hole in the periphery of the iris (iridotomy), which allows aqueous humor to flow more easily out of the anterior chamber and reduces intraocular pressure. 
EXAMPLES OF LASER THERAPY: Trabeculoplasty   (laser therapy) for chronic open-angle glaucoma causes scarring in the drainage angle, improving aqueous humor outflow and reducing intraocular pressure. Argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT) are used. SLT, which is as effective as ALT, uses a lower power laser and may be repeated, because the lower level of energy should cause less scarring.

11. Pathology: Eye (Cont’d)
Pages 712 – 713
Pathology: Eye (Cont’d)
Hordeolum (stye)
Macular degeneration
Nystagmus
Retinal detachment
Strabismus
HORDEOLUM (hŏr-DĒ-ō-lŭm) Localized, purulent, inflammatory staphylococcal infection of a sebaceous oil-producing gland in the eyelid; Also known as a stye or sty
TREATMENT: Hot compresses may help localize the infection and promote drainage. In some cases, surgical incision is necessary.
MACULAR DEGENERATION (MĂK-ū-lăr dē-jĕn-ĕ-RĀ-shŭn) Progressive damage to the macula of the retina and producing a loss of central vision; one of the leading causes of blindness in the elderly. (Figure 17-11). There are two forms which include “dry” and a “wet” macular degeneration.
DRY: affects about 85% of patients and is marked by atrophy and degeneration of retinal cells and deposits of clumps of extracellular debris, or drusen. 
TREATMENT: no treatment other than attempting to slow the progression of the disease by taking vitamin and mineral supplements, and actions such as smoking cessation.
WET: development of new [neovascular] and leaky [exudative] blood vessels close to the macula.
TREATMENT: laser photocoagulation of the leaking vessels and injection of medication into the vitreous jelly that promotes regression of abnormal blood vessels. Unfortunately, in many cases, patients with wet macular degeneration have more severe vision loss, and success of treatment is limited.
NYSTAGMUS (nĭ-STĂG-mŭs) Repetitive, rhythmic movements of one or both eyes
ETIOLOGY: Brain tumors or diseases of the inner ear; however, it is normal in newborns.
RETINAL DETACHMENT (RĔ-tĭ-năl dē-TĂCH-mĕnt) Separation of the two layers of the retina from each other
ETIOLOGY: Trauma to the eye, head injuries, bleeding, scarring from infection, or shrinkage of the vitreous humor can produce holes or tears in the retina and result in the separation of layers.
SYMPTOM: photopsia [bright flashes of light] and floaters [black spots or filmy shapes]. Later patients, may notice a shadow or curtain falling across the field of vision.
TREATMENT: To repair smaller retinal tears – photocoagulation [making pinpoint burns to form scar tissue and seal holes] and cryotherapy [creating a “freezer burn” that forms a scar and knits a tear together]; For larger retinal detachments – a scleral buckle made of silicone [sutured to the sclera directly over the detached portion of the retina to push the two retinal layers together] or pneumatic retinopexy [a gas bubble is injected into the vitreous cavity to put pressure on the area of retinal tear until the retina is reattached].
STRABISMUS (stră-BĬZ-mŭs) A failure of the eyes to look in the same direction because of weakness of a muscle controlling the position of one eye (Figure 17-12).
EXAMPLE:
ESOTROPIA (ĕs-ō-TRŌ-pē-ă) Turning inward of one or both eyes; Also known as cross-eyes
EXOTROPIA (ĕk-sō-TRŌ-pē-ă) Turning to the side or outward of one or both eyes
HYPERTROPIA (hī-pĕr-TRŌ-pē-ă) upward deviation of one eye
HYPOTROPIA (hī-pō-TRŌ-pē-ă) downward deviation of one eye
TREATMENT: medications in the form of eye drops, corrective lenses, eye exercises with patching of the normal eye, or surgery to restore muscle balance.
COMPLICATION: In children, it may lead to amblyopia (ăm-blē-Ō-pē-ă) [partial loss of vision from “lazy eye”]. Amblyopia is reversible until the retina is fully developed, at the age of 7 to 10 years. When strabismus develops in an adult, diplopia (dĭp-LŌ-pē-ă) [double vision] is a common problem.

12. Eyelid Abnormalities Pages 710 – 713 Blepharitis Dacryocystitis
Ectropion
Entropion
Ptosis
Xanthelasma
BLEPHARITIS (blĕf-ă-RĪ-tĭs) Inflammation of an eyelid, causing redness, crusting, and swelling along lid margins – See Figure 17-6A.
DACRYOCYSTITIS (dăk-rē-ō-sĭs-TĪT-ĭs) Blockage, inflammation, and infection of a nasolacrimal duct and lacrimal sac, causing redness and swelling in the region between the nose and the lower lid
ECTROPION (ĕk-trō-pē-ăn) Outward sagging and eversion of the eyelid, leading to improper lacrimation and corneal drying and ulceration
ENTROPION (ĕn-trō-pē-ăn) Inversion of the eyelid, causing the lashes to rub against the eye; corneal abrasion may result
PTOSIS (tōsĭs) Drooping of upper lid margin from neuromuscular problems or trauma
XANTHELASMA (zăn-thĕ-lăz-mă) Raised yellowish plaque on eyelid caused by lipid disorder.

13. Clinical Procedures: Diagnostic
Page 714
Clinical Procedures: Diagnostic
fluorescein angiography
ophthalmoscopy
slit lamp microscopy
FLUORESCEIN ANGIOGRAPHY (floo-ō-RĔS-ē-ĭn ăn-jē-ŎG-ră-fē) Process of recording [viewing and photographing] the circulation of a fluorescein dye through the blood vessels of the retina
USE TO TEST: blood flow in the retina, detects vascular changes in diabetic and hypertensive retinopathy, and identifies lesions in the macular area of the retina (Figure 17-13).
OPHTHALMOSCOPY (ŏf-thăl-MŎS-kō-pē) Visual examination of the interior of the eye. Ideally, the pupil is dilated and the physician holds the ophthalmoscope close to the patient's eye, shining the light into the back of the eye (Figure 17-14). Ophthalmologists also may use special lenses in conjunction with a head lamp or a slit lamp (Figure 17-15).
SLIT LAMP MICROSCOPY (slĭt lămp mī-KRŎS-kō-pē) Examination of anterior ocular structures [conjunctiva, sclera, cornea, anterior chamber, iris, lens, and vitreous] under microscopic magnification. Tonometry (ton/o = tension) measures intraocular pressure to detect glaucoma (Figure 17-15). Special magnifying lenses also permit examination of the fundus, as with a direct ophthalmoscope.

14. Diagnostic (Cont’d) Page 715 visual acuity test visual field test
VISUAL ACUITY TEST (VĬZ-ū-ăl ă-KŪ-ĭ-tē tĕst) Clarity of vision is assessed (Figure 17-16A); assessed by reading letters of decreasing size on an eye chart [Snellen chart] at 20 feet.
It is expressed as a ratio [20/20]. The first number is the distance the patient is standing from the chart. The second number is the distance at which a person with normal vision could read the same line of the chart. If the best a patient can see is the 20/200 line on the chart, then at 20 feet the patient can see what a “healthy” eye sees at 200 feet. Mirrors are used so that measurements can be taken at less than 20 feet and still be equivalent to those for vision measured at 20 feet.
VISUAL FIELD TEST (VĬZ-ū-ăl fēld tĕst) Measurement of the entire scope of vision [peripheral and central] when the eyes are fixed, looking straight ahead without movement of the head. (Figure 17-16B)

15. Treatment Pages 716 – 718 enucleation phacoemulsification keratoplasty
scleral buckle
laser photocoagulation
vitrectomy
LASIK
ENUCLEATION (ē-nū-klē-Ā-shun) Removal of the eyeball from the orbit of the eye
USED TO TREAT: tumors → ocular melanoma [malignant tumor of pigmented cells in the choroid layer] or if an eye has become blind/painful from trauma or disease, such as glaucoma.
KERATOPLASTY (kĕr-ă-tō-PLĂS-tē) Surgical removal of the patient's scarred or opaque cornea and replacement with a donor cornea [“button” or graft], which is then sutured into place (Figure 17-17); Also known as a corneal transplant
PICTURE
LASER PHOTOCOAGULATION (LĀ-zĕr fō-tō-kō-ăg-ū-LĀ-shŭn) Intense, precisely focused light beam (argon laser) creates an inflammatory reaction that seals retinal tears and leaky retinal blood vessels.
USED TO TREAT: retinal tears, diabetic retinopathy, and wet macular degeneration
LASIK (lā-sĭk) [laser in situ keratomileusis (shaping the cornea)] Use of an excimer laser to correct errors of refraction (myopia, hyperopia, and astigmatism). The surgeon lifts the top layer of the cornea (a flap is made) and uses a laser to sculpt the cornea it is performed as an outpatient procedure with use of local anesthesia. (Figure 17-18).
PHACOEMULSIFICATION (făk-ō-ĕ-mŭl-sĭ-fĭ-KĀ-shŭn) A technique of cataract extraction using ultrasonic vibrations break up the lens; the pieces are then aspirated through the ultrasonic probe. In most patients, a foldable intraocular lens (IOL) is implanted at the time of surgery. (Figure 17-19)
SCLERAL BUCKLE (SKLĔ-răl BŬ-kl) Procedure to suture a band of silicone on the sclera directly over a detached portion of the retina. The band pushes the two parts of the retina against each other to bring together the two layers of the detached retina (Figure 17-20).
VITRECTOMY (vĭ-TRĔK-tō-mē) Removal of the vitreous humor which is replaced with a clear solution; necessary when blood and scar tissue accumulate in the vitreous humor [a complication of diabetic retinopathy].

16. Abbreviations – The Eye
Page 718
Abbreviations – The Eye
ALT OS
AMD OU
HEENT
PERRLA
IOL
POAG
IOP
PRK
LASER VA
LASIK
SLT OD VF
ALT = argon laser trabeculoplasty
AMD = age-related macular degeneration
HEENT = head, eyes, ears, nose, and throat
IOL = intraocular lens
IOP = intraocular pressure
LASIK = laser in situ keratomileusis
OD = right eye (Latin, oculus dexter)
OS = left eye (Latin, oculus sinister)
OU = both eyes (Latin, oculus uterque, “each eye”)
PERRLA = pupils equal, round, reactive to light and accommodation
POAG = primary open-angle glaucoma
PRK = photorefractive keratectomy—a laser beam flattens the top layer of the cornea to correct myopia
SLT = selective laser trabeculoplasty
VA = visual acuity
VF = visual field

17. Vocabulary – The Ear Page 721 auditory canal labyrinth auditory meatus
malleus
auditory nerve fibers
organ of Corti
auditory tube
ossicle
auricle
oval window
cerumen
perilymph
cochlea
pinna
endolymph
semicircular canals
eustachian tube
stapes
incus
tympanic membrane
vestibule
AUDITORY CANAL (ĂW-dĭ-tō-rē kă-NĂL) Channel leading from the pinna [ear flap] to the eardrum
AUDITORY MEATUS (ĂW-dĭ-tō-rē mē-Ā-tŭs) Opening of the auditory canal to the outside of the body
AUDITORY NERVE FIBERS (ĂW-dĭ-tō-re nĕrv FĪ-bĕrz) These carry impulses from the inner ear to the brain [cerebral cortex]. These fibers compose the vestibulocochlear nerve [cranial nerve VIII].
AUDITORY TUBE (ĂW-dĭ-tō-rē toob) Channel between the middle ear and the nasopharynx [throat]; Also known as the Eustachian tube
AURICLE (ĂW-rĭ-kl) the protruding part of the external ear; Also known as the flap of the ear or pinna
CERUMEN (sĕ-ROO-mĕn) Waxy substance secreted by the external ear; Also known as earwax
COCHLEA (KŎK-lē-ă) Snail shell–shaped, spirally wound tube in the inner ear; contains hearing-sensitive receptor cells
ENDOLYMPH (ĔN-dō-lĭmf) Fluid within the labyrinth (canals) of the inner ear; conducts sound waves
EUSTACHIAN TUBE (ū-STĀ-shŭn toob) Channel between the middle ear and the throat; Also known as auditory tube
INCUS (ĬNG-kŭs) Small anvil-shaped bone [ossicle] in the middle ear; second ossicle
LABYRINTH (LĂB-ĭ-rĭnth) Maze-like series of canals of the inner ear; includes the cochlea, vestibule and semicircular canals
MALLEUS (MĂL-ē-ŭs) Hammer-shaped, small bone (ossicle) in the middle ear; it is the first of the three ossicles
ORGAN OF CORTI (ŎR-găn of CŎR-tē) Sensitive auditory receptor area found in the cochlea of the inner ear
OSSICLE (ŎS-ĭ-kl) Small bone [malleus, incus, or stapes] of the middle ear
OVAL WINDOW (Ō-văl WĪN-dō) Membrane between the middle and inner ears
PERILYMPH (PĔR-ĭ-lĭmf) Fluid contained in the labyrinth [canals of the inner ear]
PINNA (PĬN-ă) Outer ear flap; Also known as an auricle
SEMICIRCULAR CANALS (sĕ-mē-SĔR-kū-lăr kă-NĂLZ) Passageways in the inner ear that are associated with maintaining equilibrium
STAPES (STĀ-pēz) Small, stirrup-shaped bone in the middle ear; third ossicle
TYMPANIC MEMBRANE (tĭm-PĂN-ĭk MĔM-brān) Membrane between the outer and middle ear; Also known as the eardrum
VESTIBULE (VĔS-tĭ-būl) Central cavity of the labyrinth, connecting the cochlea and semicircular canals. It contains two structures, the saccule and utricle, that help to maintain equilibrium.

18. Combining Forms Pages 722 – 723
Meaning Example
acous/o, audi/o, audit/o aur/o, auricul/o, ot/o cochle/o mastoid/o myring/o, tyman/o
hearing
ear
cochlea
mastoid process
eardrum, tympanic membrane
acoustic, audiogram, audiologist, auditory
aural, postauricular, otic, otomycosis, otopyorrhea, otolaryngologist
cochlear
mastoiditis
myringotomy, myringitis, tympanoplasty
ACOUSTIC (ă-KOOS-tĭk) Pertaining to hearing
AUDIOGRAM (ĂW-dē-ō-grăm) Record of hearing using an audiometer
AUDIOLOGIST (ăw-dē-ŎL-ō-gĭst) Healthcare professional specializing in the evaluation and rehabilitation of people with hearing loss
auditory 
AURAL (ĂW-răl) Pertaining to the ear
POSTAURICULAR (pōst-aw-RĬK-ū-lăr) Pertaining to behind the ear
OTIC (Ō-tĭk) Pertaining the ear
OTOMYCOSIS (ō-tō-mī-KŌ-sĭs) Fungal infection of the ear
OTOPYORRHEA (ō-tō-pī-ō-RĒ-ă) Discharge of pus from the ear
OTOLARYNGOLOGIST (ō-tō-lă-rĭn-GŎL-ō-jĭst) Specialist (surgeon) in ear, nose and throat disorders
COCHLEAR (KŎK-lē-ăr) Pertaining to the cochlea
MASTOIDITIS (măs-toy-DĪ-tĭs) Inflammation and infection of the mastoid process [posterior portion of the temporal bone extending downward behind the external auditory meatus] just behind the ear
ETIOLOGY: bacterial infection, spreads from the middle ear.
MYRINGOTOMY (mĭr-ĭn-GŎT-ō-mē) Incision of the eardrum
MYRINGITIS (mĭr-ĭn-JĪ-tĭs) Inflammation of the eardrum
TYMPANOPLASTY (tĭm-pă-nō-PLĂS-tē) Surgical repair of the eardrum (Figure 17-24 shows a normal tympanic membrane (eardrum).)

19. Combining Forms (cont’d)
Pages 722 – 723
Combining Forms (cont’d)
Meaning Example
ossicul/o salping/o staped/o vestibul/o
ossicle
Eustachian tube
stapes
vestibule
ossiculoplasty
salpingopharyngeal
stapedectomy
vestibulocochlear
OSSICULOPLASTY (ŏs-ĭ-kū-lō-PLĂS-tē) Surgical repair of an ossicle [small bone] of the middle ear
SALPINGOPHARYNGEAL (săl-pĭng-gō-fă-RĬN-gē-ăl) Pertaining to the eustachian tube and the throat
In the context of female reproductive anatomy, salping/o means the fallopian tubes.
STAPEDECTOMY (stā-pĕ-DĔK-tō-mē) Removal of the stapes (third middle ear bone)
After stapedectomy a prosthetic device is used to connect the incus and the oval window (Figure 17-23).
VESTIBULOCOCHLEAR (vĕs-tĭb-ū-lō-KŌK-lē-ăr) Pertaining to the vestibule and cochlea

20. Suffixes Page 723 -acusis, -cusis -meter -otia hearing
Meaning Example
-acusis, -cusis -meter -otia
hearing
instrument for measure
ear condition
hyperacusis, presbycusis
audiometer
macrotia
HYPERACUSIS (hī-pĕr-ă-KŪ-sis) Excessive sensitivity to sounds
PRESBYCUSIS (prĕz-bē-KŪ-sĭs) Progressive loss of hearing, occurring in middle and older age
AUDIOMETER (ăw-dē-ŎM-ĕ-tĕr) Instrument to measure or test hearing
MACROTIA (măk-RŌ-shē-ă) Abnormally large ears
ETIOLOGY: congenital anomaly.

21. Pathology: Ear Page 724 acoustic neuroma cholesteatoma deafness
Ménière disease
ACOUSTIC NEUROMA (ă-KOOS-tĭk nū-RŌ-mă) Benign tumor arising from the acoustic vestibulocochlear nerve [eighth cranial nerve] in the brain.
SYMPTOM: Initially, this tumor causes tinnitus [ringing in the ears], vertigo [dizziness], and decreased hearing.
TREATMENT: Small tumors are resected by microsurgical techniques or ablated [removed] by radiosurgery [using powerful and precise x-ray beams rather than a surgical incision].
CHOLESTEATOMA (kō-lē-stē-ă-TŌ-mă) Middle ear cyst-like mass of cellular debris and cholesterol crystals; they produce a foul-smelling discharge and are most often the result of chronic otitis media. They are associated with perforations of the tympanic membrane (Figure 17-24B).
DEAFNESS (DĔF-nĕs) Loss of the ability to hear.
EXAMPLE:
Nerve deafness (sensorineural hearing loss) results from impairment of the cochlea or auditory (acoustic) nerve. 
Conductive deafness results from impairment of the middle ear ossicles and membranes transmitting sound waves into the cochlea.
TREATMENT: Hearing aids help people with conductive or sensorineural hearing loss. These devices have a microphone to pick up sounds, an amplifier to increase their volume, and a speaker to transmit amplified sounds. See Figure 17-25
MENIERE DISEASE (mĕn-YĔRZ dĭ-ZĒZ) Disorder of the labyrinth of the inner ear; elevated endolymph (fluid) pressure within the cochlea (cochlear hydrops) and semicircular canals (vestibular hydrops)
SYMPTOM: tinnitus, heightened sensitivity to loud sounds, progressive loss of hearing, headache, nausea, and vertigo. Attacks last minutes or continue for hours.
ETIOLOGY: unknown
TREATMENT: bed rest, sedation, and drugs to combat nausea and vertigo. Surgery may be necessary to relieve accumulation of fluid from the inner ear.

22. Pathology: Ear (cont’d)
Page 725
Pathology: Ear (cont’d)
otitis media
Myringotomy
otosclerosis
tinnitus
vertigo
OTITIS MEDIA (ō-TĪ-tĭs MĒ-dē-ă) Inflammation of the middle ear
EXAMPLE:
ACUTE OTITIS MEDIA (ă-kūt ō-TĪ-tĭs MĒ-dē-ă) infection of the middle ear following an upper respiratory infection (URI). SYMPTOM: pus formation, pain and fever with redness and loss of mobility of the tympanic membrane; Also known as suppurative otitis media (Figure 17-24C)
TREATMENT: antibiotics, but if the condition becomes chronic, myringotomy may be required to ventilate the middle ear.
SEROUS OTITIS MEDIA (SĔR-ŭs ō-TĪ-tĭs MĒ-dē-ă) Non-infectious inflammation of the middle ear with accumulation of clear fluid. It often results from a dysfunctional or obstructed auditory tube.
TREATMENT: myringotomy to aspirate fluid and placement of tympanostomy tubes in the eardrum to allow ventilation of the middle ear (Figure 17-24D).
OTOSCLEROSIS (ō-tō-sklĕ-RŌ-sĭs) bone forms around the oval window and causes fixation or ankylosis (stiffening) of the stapes bone (ossicle)
ETIOLOGY: hereditary condition
COMPLICATION: Conduction deafness occurs, as the ossicles cannot pass on vibrations when sound enters the ear.
TREATMENT: Stapedectomy with replacement by a prosthesis (artificial part) restores hearing. In order to perform this operation, the oval window must be fenestrated (opened) using a laser. (Figure 17-23)
TINNITUS (TĬN-nĭ-tŭs) Sensation of noises [ringing, buzzing, whistling, booming or roaring] in the ears; can be persistent and severe and can interfere with the affected person's daily life.
ETIOLOGY: irritation of delicate hair cells in the inner ear
MAY BE INDICATIVE OF: presbycusis, Meniere disease, otosclerosis, chronic otitis, labyrinthitis, and other disorders.
TREATMENT: medication and biofeedback to manage stress and anxiety if these are contributing factors.
VERTIGO (VĔR-tĭ-gō) Sensation of irregular or whirling motion either of oneself or of external objects; Equilibrium and balance are affected, and nausea may occur as well
ETIOLOGY: disease in the labyrinth or in the nerve that carries messages from the semicircular canals to the brain.

23. Clinical Procedures Page 726 Audiometry Cochlear implant
Ear thermometry
Otoscopy
Tuning fork test
Rinne
Weber
AUDIOMETRY (ăw-dē-ŎM-ĕ-trē) The process of testing hearing. An audiometer is an electrical device that delivers acoustic stimuli of specific frequencies to determine a patient's hearing loss for each frequency (Figure 17-26A). Results are shown on a chart or audiogram (Figure 17-26B).
COCHLEAR IMPLANT PROCEDURE (KŎK-lē-ăr) Surgical insertion of a device that allows sensorineural hearing–impaired persons to understand speech. Electrical signals are sent directly into the auditory nerve by means of multiple electrodes inserted into the cochlea. An external microphone and speech processor pick up sound signals and convert them to electrical impulses (Figure 17-27A).
EAR THERMOMETRY (ēr thĕr-MŎM-ĕ-trē) Measurement of the temperature of the tympanic membrane by detection of infrared radiation from the eardrum. A device is inserted into the auditory canal, and results, which reflect the body's temperature, are obtained within 2 seconds.
OTOSCOPY (ō-TŎS-kō-pē) Visual examination of the ear using an otoscope (Figure 17-27B)
TUNING FORK TEST (TOO-nĭng fŏrk tĕst) Test of ear conduction using a vibration source [tuning fork].
EXAMPLE:
Rinne test = vibrating tuning fork is placed against the patient's mastoid bone [bone conduction] and in front of the auditory meatus [air conduction].
Weber test = vibrating tuning fork is placed on the center of the forehead. The perceived loudness of sound is the same in both ears if hearing is normal.

24. Abbreviations – The Ear
Page 727
Abbreviations – The Ear AD
ETD
AOM
HEENT AS
PE tube
EENT
SOM
ENG
ENT
AD = right ear (Latin, auris dextra)
AOM = acute otitis media
AS = left ear (Latin, auris sinistra)
EENT = eyes, ears, nose, and throat
ENG = electronystagmography—a test of the balance mechanism of the inner ear by assessing eye movements (nystagmus is rapidly twitching eye movements)
ENT = ears, nose, and throat
ETD = eustachian tube dysfunction
HEENT = head, eyes, ears, nose, and throat
PE tube = pressure-equalizing tube—a polyethylene ventilating tube placed in the eardrum (to treat recurrent episodes of acute otitis media)
SOM = serous otitis media