Special Senses

Word Parts Belphar/o: eyelid Chromat/o: color Choroid/o: choroid coat Conjunctiv/o: conjunctiva Cochle/o: cochlea Corne/o: cornea Cor/o, core/o, pupill/o: pupil Dacry/o, lacrim/o: tear

Word Parts Irid/o: iris Ocul/o: eye Phot/o: light Presby/o: old age Retin/o: retina Stigmat/o: point, mark

Word Parts Ton/o: tension Eso-: inward -tropia: turning -ptosis: prolapse, sagging -acusis, -cusis: hearing -opia, -opsia: vision Acous/o, audi/o, audit/o: hearing Myring/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 interpreted Ears: 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