Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 1 Chapter 19 Visual and Auditory Systems
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved Describe the functions of the eyes and ears. 2. List the major components of the eyes. 3. List the various infections that affect the eyes. 3a. Describe the different types of conjunctivitis and their treatments. 3b. Describe what causes glaucoma. 3c. Explain how medications work to relieve glaucoma. Anatomy, Conditions, and Treatments of the Eyes Lesson 19.1
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved List the major components of the ears. 5. List the various infections that affect the ears. 6. Drugs affecting the visual and auditory systems: a. List both trade and generic drug names covered in this chapter. b. Explain the drug action of the medications listed. Anatomy, Conditions, and Treatments of the Ears Lesson 19.2
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 4 Introduction Five main senses of body system are sight, hearing, touch, smell, taste. Two senses that can change ____ dramatically are seeing and hearing. Equilibrium is another sense that plays a role in the ability to ______.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 5 The Eyes (Opthalmic System) Eyes link outside world to the ____. Images translate into impulses that create lasting memories in the mind. Three different levels of eye specialists: Opticians make lenses. Optometrists perform eye exams. Ophthalmologists are medical ______
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 6 Anatomy of the Eye Eyebrows shade eyes from _______. Eyelashes (more than ______) catch debris, keep eyes moist, shade the eyes. Orbit is ______ socket that holds the eye. Eye position is 100 degrees peripheral vision.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 7 Anatomy of the Eye (cont’d) Eyelids: Eyelids have four layers (outer skin, muscles, connective tissue, __________. Layers allow the eyes to open and close. Blinking protects eyes from foreign objects. ________ fluid cleanses the eye.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 8 Anatomy of the Eye (cont’d) Conjunctiva is thin transparent layer, mucous membrane, covers ______ eyelids and sclera. Lacrimal gland, in orbit, secretes tear into eye; has ducts to nasal cavity. Lysozyme is enzyme in _____ with antimicrobial properties.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 9 Anatomy of the Eye (cont’d)
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 10 Anatomy of the Eye (cont’d) Cornea: transparent cover allows ______ into the eye Connective tissue covered with thin epithelial layer No blood ______—nourished by aqueous humor (tissue fluid) and oxygen Nerve fibers sensitive to pain
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 11 Anatomy of the Eye (cont’d) Sclera: Attached to cornea; wraps around back of ________ White portion of eye: many fibers and muscles with opening for optic nerve Optic _______ sends images to brain for interpretation
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 12 Anatomy of the Eye (cont’d) Choroid coat: layer inside sclera Fovea: _____most layer where sharpest vision occurs Sclera joins with iris and ciliary body in front of eye Iris: _______ part of eye to filter light
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 13 Anatomy of the Eye (cont’d) Posterior cavity: ________ space in eye; surrounded by lens, ciliary body, retina Ciliary body: forms ring around front of eye; holds lens in place Vitreous body: holds ______ and form of eye Vitreous humor: nourishes and ______ eye
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 14 Anatomy of the Eye (cont’d) Retina: Thin layer; contains layers of neurons, nerves, pigmented epithelium, membranous tissues Receptor cells responsible for ______ Six muscles responsible for eye movements
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 15 Eye Muscles and Direction of Movement
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 16 Anatomy of the Eye (cont’d) Pupil: Dilates (mydriasis) when focusing on ______ figure or darkness Constricts (miosis) in extreme light Aqueous humor provides the nutrients and oxygen to maintain lens and cornea.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 17 Anatomy of the Eye (cont’d) Aqueous humor: Accumulates; must be released to maintain _______ Canal of Schlemm: ducts used to release aqueous humor Retina contains nerve endings to transmit electrical impulses to _____.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 18 Vision Retina contains ____ and ________ responsible for vision. Rods: sight in dim light; produce black and white images. Cones detect ______. Rods and cones synapse with nerve endings; signals sent through optic nerve to brain. Occipital lobe—visual interpretation.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 19 Conditions That Affect the Eye New developments/treatments: Laser surgery-correct vision Lens implantation—for blindness Conditions: glaucoma, conjunctivitis, congestion of eye, viral and bacterial infections
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 20 Allergies With allergies, eyes become itchy, red and watery. Treatment includes: avoiding irritants, getting allergy shots, _____ cell stabilizers, antihistamines, and decongestants.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 21 Drug Treatment for Allergies Mast cell stabilizers: prevent allergy cells from opening and releasing chemicals that cause ______________. Solutions, suspensions, systemic agents Antihistamines and decongestants alleviate symptoms of and inflammation. Corticosteroids: relieve __________.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 22 Conjunctivitis Conjunctivitis known as “_____ ____.” Is common in daycare centers; contagious. Is acute inflammation of the conjunctiva. Causes include: viral, bacterial, fungal, allergies. Symptoms include: inflammation, itching, burning, white ____________. Wash hands and avoid touching the eyes.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 23 Drug Treatment for Conjunctivitis ____ treatment for viral infection; antibiotics for bacterial infection Antiinfectives: vidarabine, natamycin, gentamicin, ciprofloxacin Ophthalmic sulfonamides ________glycosides Macrolides
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 24 Cataracts Cataracts are characterized by a _____ over the eyes. Vision becomes blurred; can lead to blindness. Cause: formation of ________ buildup onto the lens. Eyeglasses/contacts can clear up vision problems. Surgery
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 25 Cataracts (cont’d) Mydriatic-cycloplegic drugs used to _______- eyes Atropine, cyclopentolate, homatropine tropicamide
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 26 Glaucoma Pressure within the eyes is _____ than normal (increased ocular pressure [IOP]). Two causes: overproduction of aqueous humor; blocked ducts that drain excess aqueous humor. Left untreated, causes __________. Types of glaucoma include primary, acute congestive, and chronic simple.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 27 Drug Treatment for Glaucoma β-adrenergic blockers: lower intraocular pressure Carbonic anhydrase inhibitors _________: reduce intraocular pressure Sympathomimetics: decrease aqueous humor Prostaglandin agonists: increase outflow of aqueous humor
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 28 Blindness Blindness is ______ or total lack of vision. Blindness has many causes. Macular degeneration - only peripheral vision Retinitis pigmentosa: field of vision is limited to a small circular opening in the middle. Most common treatment: eye_______.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 29 Blindness (cont’d) __________ transplant—may correct blindness. _______ cell transplant—may reverse blindness.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 30 Miscellaneous Ophthalmic Agents Artificial tears bought _____. Used to relieve dry eyes, irritation. Ingredients include: sodium chloride, buffers to adjust pH, additives to prolong effects. Dosage form is _________. Comes in various strengths, combinations.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 31 Miscellaneous Ophthalmic Agents (cont’d) All contain sodium _________ and all used for same reasons. Artificial tear inserts available by prescriptions for dry eye syndrome, severe keratoconjunctivitis.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 32 Artificial Tears Products Trade NameManufacturerIngredients Tear DropParmedPolyvinyl alcohol, NaCl, EDTA, benzalkonium Cl Artificial TearsVarious mfgPolyvinyl alcohol, povidone, NaCl, chlorbutanol CellufreshAllerganCarboxymethylcellulose, NaCl, KCl, Na lactate RefreshAllerganPolyvinyl alcohol, povidone, NaCl Just TearsBlairexBenzalkonium Cl, EDTA, polyvinyl alcohol, NaCl MurineRossPolyvinyl alcohol, povidone, benzalkonium Cl, dextrose, EDTA, NaCl, sodium bicarbonate, sodium phosphate RestasisAllerganCyclosporine, glycerin, polysorbate,, carbomer, purified water, sodium hydroxide
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 33 The Ears (Auditory System) Human ear responsible for hearing, _________, equilibrium, communication skills. Ear is composed of three sections: external, middle, inner. External ear—auricle; composed of cartilage and skin; entrance for sound waves.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 34 Anatomy of the Ear
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 35 External Ear Auditory canal: about __ inch long; leads to tympanic membrane (________). There are two major functions of tympanic membrane: protection of middle ear from foreign objects; transmission of sounds to middle ear. Sounds transmitted by vibrations. Cerumen is ____ substance produced by glands.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 36 Middle Ear Vibration carried to middle ear. Cavity (space) contains bony structures (ossicles): ________, incus, stapes. Ossicles connected to each other. Eustacian tube: Eustacian tube leads to nasopharynx. It __________ pressure between outside and inside atmosphere.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 37 Inner Ear Stapes continues transfer of sound to inner ear. Fluid-filled cavity—_________; comprise many components that process and transmit audible sounds via nerve impulses to brain. There are two areas: perilymph, membrane division.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 38 Inner Ear (cont’d) Three main areas of the inner ear include: Cochlea _________ Semicircular canal
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 39 Conditions Affecting the Ear Various conditions affect quality of hearing: infections, ____ ____ accumulation, damage to eardrum, genetic defects. Most infections are viral but may lead to bacterial infection as well.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 40 Deafness Causes include: aging, heredity, infections, ______ ________, medications, trauma. Loud noises break hair-like structures in middle ear; do not regenerate No medication available—hearing aids, implants.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 41 Otitis Media Otitis media is infection of the middle ear associated with inflammation of eustachian tube. Sore throat—can lead to middle ear infection— often seen in _______. For reoccurring infections, insertion of small tubes by physicians to drain middle ear.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 42 Drug Treatment for Otitis Media Antiinfectives: treat infection Antibiotics if infection is severe: ____________ or sulfamethoxazole/trimethoprim Antihistamines, decongestants, and analgesics: treat _________
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 43 Cerumen Buildup Excessive wax builds up or dries—impedes ______ quality. Doctor removes wax buildup. Irrigation kit includes saline solution and ear syringe. Other treatments include: mineral oil, glycerin, or hydrogen ________ in the ear to soften the wax.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 44 Ototoxicity Ototoxicity caused by some drugs. Tinnitus—buzzing or _______ in ears—if untreated leads to permanent ear damage. Balance may also be affected. Prognosis: some cases reverse themselves; others cause permanent hearing loss.
Copyright © 2013 by Saunders, an imprint of Elsevier Inc. All rights reserved. 45 Miscellaneous Otic Preparations Bacterial infections treated with bactericidal or bacteriostatic preparations. All ear agents—combinations—antibiotics, steroids, ear wax removers.