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Transcript of Chapter041
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Timby/Smith: Introductory Medical-Surgical Nursing, 10/e
Timby/Smith: Introductory Medical-Surgical Nursing, 10/e
Chapter 41: Introduction to the Sensory System
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Anatomy, Physiology of the Eye Anatomy, Physiology of the Eye
• Extraocular Structures
– Eyelids, eyelashes, tears: Protect the eye
– Canthus: Where eyelids meet; Usually horizontal; Down syndrome; Epicanthal fold
– Blinking: Clears dust, particles from eye surface
– Eyelids: Adjust amount of light entering eyes; Distribute tears; Multiple glands; Conjunctiva; Caruncle; Lacrimal apparatus
– Tears: Water, Sodium chloride, lysozyme
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Anatomy, Physiology of the EyeAnatomy, Physiology of the Eye
Figure 41-1 External
structures of the eye and position of the lacrimal
structures
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Intraocular StructuresIntraocular Structures• Three Layers
– Sclera (White of the eye)
• Protects structures within the eye
• Connects to cornea, anterior chamber, pupil
– Uvea (Vascular coat of the eye)
• Choroid; Iris; Pupil; Aqueous humor; Vitrous humor
– Retina
• Rods and cones; Macula
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
The EyeThe Eye
Figure 41-2 Three-dimensional cross-section of the eye
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Visual FunctionVisual Function• Light Nerve signals: Interpreted in cerebral cortex
• Refraction; Rods, cones Optic nerve; Accommodation
• Near point; Cataract: Opaque lens, blurred, cloudy images
Figure 41-3 A normal opthalmoscopic picture. The fundus or back of the eye as seen through an ophthamoscope. The optic disc, with its radiating vasculature, is easily distinguished from the macula lutea.
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Nursing AssessmentNursing Assessment• Client History
– Allergy; Vision changes; Discomfort; Corrective lenses
– Eye medications; Eye trauma, disease, surgery
– Family history of eye disease
• Physical Assessment
– Symmetry
– Inflammation; Exudate
– Pupil constriction
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Eye Assessment Eye Assessment • Visual Screening Tests
– Snellen eye chart: Visual acuity
– Jaeger chart; Rosenbaum Pocket Vision Screener: Near vision
– Ishihara polychromatic plates: Color vision
• Extraocular Muscle Function
– Corneal light reflex test: Eye alignment
– Cover-uncover test: Extraocular muscle function
– Positions test: Eye muscle strength, cranial nerve function
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Diagnostic StudiesDiagnostic Studies• Ophthalmoscopy: Examination of fundus
• Retinoscopy: Focusing power of each eye
• Tonometry: Intraocular pressure
– Normal IOP: 10 to 21 mm Hg
• Visual Field Examination
– Peripheral vision; Gaps
– Visual field change associations: Glaucoma; Stroke; Brain tumor; Retinal detachment
• Color Vision Testing: Color differentiation ability
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Diagnostic StudiesDiagnostic Studies• Amsler Grid: Macular problems
• Slit-lamp Examination: Magnifies eye surface
– Identifies: Corneal abrasions; Iritis; Cataracts; Conjunctivitis
• Retinal Angiography: Vascular changes, blood flow
• Ultrasonography: Used when posterior of eye difficult to visualize
• Retinal Imaging: High-resolution; Pupil dilation unnecessary
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Nursing ManagementNursing Management• Client Education
– Maintenance, preservation of eye function
• Obtain an Accurate Baseline
• Client Assessment for Further Action
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Anatomy and Physiology of the Ear Anatomy and Physiology of the Ear • Subdivisions of the Ear: Outer; Middle; Inner
– Outer ear (Auricle)
• Pinna; External acoustic meatus; Tympanic membrane
– Middle ear
• Eustachian tubes; Malleus; Incus; Stapes
– Inner ear (Labyrinth)
• Cochlea (hearing); Semicircular canals (balance); Vestibulocochlear nerve (Cranial nerve VIII; Organ of Corti
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Subdivisions of the EarSubdivisions of the Ear
Figure 41-8Diagram of the ear, showing the external, middle, and
internal subdivisions.
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Ear AssessmentEar Assessment
• Basic Auditory Acuity Tests
– Whisper test: Gross auditory acuity
• Otoscopic Examination: External acoustic canal, tympanic membrane inspection
• Tuning Fork Tests
– Conductive or sensorineural hearing loss
– Rinne test; Weber test
• Romberg Test: Ability to sustain balance
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Diagnostic StudiesDiagnostic Studies• Audiometry: Precise measurement of hearing
acuity; Measured in decibels (dB)
– Lowest perceptible sound perceived: 20 dB
– Painful sound level: 120 dB
• Caloric Stimulation Test Nystagmus
– Measures vestibular reflexes of inner ear
• Electronystagmography: Vestibular function
– Used in conjunction with caloric stimulation test
– Measures duration, velocity of eye movements during nystagmus
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
Nursing ManagementNursing Management
• Client Assessment: Ear structure; Hearing function
– Screening in healthcare settings
– Baseline for further testing, referral
– Client education: Maintenance of hearing function and testing
Copyright © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins
End of Presentation