Special Senses

Word PartsBelphar/o: eyelidChromat/o: colorChoroid/o: choroid coatConjunctiv/o: conjunctivaCochle/o: cochleaCorne/o: corneaCor/o, core/o, pupill/o: pupilDacry/o, lacrim/o: tear

Word Parts

Irid/o: irisOcul/o: eyePhot/o: light Presby/o: old ageRetin/o: retinaStigmat/o: point, mark

Word PartsTon/o: tension Eso-: inward-tropia: turning -ptosis: prolapse, sagging-acusis, -cusis: hearing -opia, -opsia: visionAcous/o, audi/o, audit/o: hearingMyring/o, tympan/o: tympanic membrane (eardrum)

Overview Eyes: special sensory organs that detect stimuli in the environment and transmit those observations to the brain to be interpretedEars: special sensory organs that enable us to hear and maintain our balance

Overview • Ophthalmology: the branch of medicine dealing

with eye disorders• Otorhinolaryngology: The branch of medicine

dealing with disorders of the ear, nose and throat “ENT”

Diseases and Conditions: Eye• Achromatopsia: a congenital, hereditary deficiency

in color perception “color-blindness”• Astigmatism: a disorder where the cornea is curved

and light scatters over the retina instead of focusing on the retina• Cataract: a degenerative disease due to age where

the lens of the eye becomes cloudy• Glaucoma: when the aqueous humor of the eye

fails to drain properly and causes pressure in the eye• Can lead to blindness

Diseases and Conditions: Eye • Conjunctivitis: inflammation of the conjunctiva that

can be caused by bacteria, allergy, irritation or a foreign body “pink eye”• Diabetic retinopathy: retinal damage in diabetic

patients with bleeding of the blood vessels in the eye impairing vision • Hordeolum: small, purulent, inflammatory infection of

a sebaceous gland of the eyelid “sty”• Macular degeneration: deterioration of the macula

resulting in central vision loss (in old age)• Myopia: near sightedness• Hyperopia: far sightedness

Diseases and Conditions: Eye • Photophobia: intolerance and sensitivity to light

that occurs in eye disorders• Retinal detachment: separation of the retina from

the choroid coat leading to blindness• Strabismus: a muscular eye disorder where the

eyes turn from their normal position• Esotropia: deviation of one eye toward the other

eye “cross-eyed”• Exotropia: deviation of one eye away from the

other eye “wall-eye”

Diagnostic Procedures• Tonometery: a test to measure the pressure inside

the eyes to screen for glaucoma• Visual acuity test: a standard eye exam to

determine the smallest letters a person can read on a Snellen chart at a distance of 20 feet

Medical and Surgical Procedures• Cataract surgery: excision of a lens affected by a

cataract• Phacoemulsification: excision of the lens by

ultrasonic vibrations that break the lens into tiny pieces which are suctioned out of the eye• Iridectomy: removal of part of the iris to relieve

glaucoma pressure• Laser iridotomy: laser surgery that cuts the iris to

drain the aqueous humor• Laser photocoagulation: a laser seals leaking

retinal blood vessels to treat diabetic retinopathy

Pharmacology • Anti-glaucoma agents: reduce the pressure in the

eye by reducing the amount of aqueous humor production or increasing its outflow• Miotics: cause the pupil to constrict• Mydriatics: cause the pupil to dilate

Diseases and Conditions: Ear • Hearing Loss: loss of sense or perception of sound • Anacusis: total deafness• Conductive: any condition that prevents sound

waves from being transmitted to auditory receptors • Presbycusis: gradual hearing loss as people grow

older• Sensorineural: the inability of nerve stimuli to be

delivered to the brain from the inner ear “nerve deafness”

Diseases and Conditions: Ear • Meniere disease: a rare disorder with progressive

deafness, vertigo, and tinnitus• Otitis media: inflammation of the middle ear as a

result of an URI “ear infection”• Otosclerosis: progressive deafness because of

ossification of the inner ear• Tinnitus: a ringing noise heard constantly or

intermittently in one or both ears• Vertigo: the sensation of moving around in space

or feeling of spinning or dizziness due to damage to the inner ear

Diagnostic Procedures• Audiometry: a test that measures hearing acuity at

various sound frequencies• Otoscopy: a visual examination of the ear canal and

tympanic membrane• Tuning fork test: hearing tests that use a tuning

fork that is struck then placed on the side of the head to assess nerve and bone sound conduction• Rinne: evaluates bone conduction in one ear at a

time• Weber: evaluates bone conduction in both ears at

once

Medical and Surgical Procedures• Cochlear implant: an electronic transmitter

implanted in the cochlea to restore hearing• Ear irrigation: flushing the ear canal with water to

remove ear wax• Myringoplasty: surgical repair of a torn eardrum

“tympanoplasty”• Myringotomy: incision of the tympanic membrane

to relieve pressure and drain fluid from the middle ear or to insert tubes in the eardrums

Pharacology

• Vertigo and motion sickness agents: decrease the sensitivity of the inner ear to motion and prevent nerve impulses from reaching the vomit center of the brain• Wax emulsifiers: loosen and help remove impacted

ear wax

Abbreviations• ARMD: age-related macular degeneration• Ast: astigmatism• ENT: ear, nose, throat• IOP: intraocular pressure• Myop: myopia• OM: otitis media• SICS: small incision cataract surgery• ST: esotropia