S E N S E S

THE VISUAL SYSTEM• The eye is a unique organ

because its external anatomy may be easily assessed. Even the internal eye is visible through the cornea, where blood vessels and Central Nervous System tissues (the retina and optic nerve) may be visualized without the use of x-rays or invasive procedures.

External Structures of the Eye• Eyelids (palpebrae) and

eyelashes: protect the eye from foreign particles

• • Conjunctiva

– Palpebral Conjunctiva: pink; lines inner surface of eyelids

– Bulbar Conjunctiva: white with small blood vessels, covers anterior sclera

External Structures of the Eye• Lacrimal apparatus (lacrimal gland

and its ducts and passages): produces tears to lubricate the eye and moisten the cornea; tears drain into the nasolacrimal duct, which empties into nasal cavity.

• Tears- lipids, dissolve salts, glucose, urea, CHON, lysozyme

• Meibomian glands- oil secreting gland on upper and lower lids

• Movement of the eye is controlled by six extraocular muscles.

Internal Structures of the Eye• Three Layers of the Eyeball

– Outer Layer• Sclera: tough, white connective

tissue (“white of the eye”); located anteriorly and posteriorly

• Cornea: transparent avascular tissue , convex in shape and 0.5 mm thick , through which light enters the eye. Powerful lens that bends and direct light to the retina. Derives O2 from the env’t.

Internal Structures of the Eye– Middle Layer /Uveal tract –

middle vascular layer that furnishes blood supply to the retina

• Choroid: highly vascular layer; located between retina and sclera, compose of 3 layers of vessels attached that both ciliary body and optic nerve; nourishes the retina

• Ciliary body: anterior to choroids, secretes acqueous humor; muscles change shape of lens

Internal Structures of the Eye– Middle Layer

• Iris: pigmented membrane behind cornea; gives color to the eye; located anteriorly; color is determined by the degree of pigmentation; 2 iris muscles (sphincter and dilator) determine pupil diameter hence regular amount of light entering the eye

• Pupil: a circular opening in the middle of the iris that constricts or dilates to regulate amount of light entering the eye.

Internal Structures of the Eye

Inner Layer: Retina

• RETINA - Thin semitransparent layer of nerve tissue that forms the innermost lining of the eye

• Light-sensitive layer composed of rods and cones (visual cells)

• a.1 Cones: specialized structure for fine discrimination and color vision; 6 million and concentrated at the center peak sensitive to red, green, and blue

• Macula – center of the retina about 5mm in dm; yellowish spot with depressed center known as fovea (point of finest vision)

• a.2 Rods: more sensitive to light than cones; aid in peripheral vision; about 125 million distributed in the periphery of the retina; fxns best in dim light (night vision/scotopic vision); sensitive to green and yellow; damage could lead to night blindness

• Optic disk: area in retina for entrance of optic nerve; has no photoreceptors, blind spot

Internal Structures of the Eye• Lens: transparent body that focuses image on retina

biconcave avascular, 4mm thick, 9 mm in dm, suspended behind the iris, consist of 65% H2O and 75% CHON

• Fluids of the Eye

– Aqueous Humor: clear, watery fluid in anterior and posterior chambers in anterior part of the eye; serves as refracting medium and provides nutrients to lens and cornea; contributes to the maintenance of intraocular pressure.

– Vitreous Humor: clear, gelatinous material that fills posterior cavity of the eye; maintains transparency and form of the eye. Account about 2/3 of the eye fluid

Visual Pathways

• Light passes through the cornea, aqueous humor, lens and vitreous humor. Retina (rods and cones) translates light waves into neural impulses that travel over the optic nerves. Optic nerves for each eye meet at the optic chiasm Optic nerves continue from optic chiasm as optic tracts and travel to the cerebrum (occipital lobe), where visual impulses are perceived and interpreted.

•

• BINOCULAR VISION – ability of the eyes to fuse 2 images into a single image

• Near vision – contraction of the ciliary muscles which increases curvature of the lens and brings near objects into focus on the retina

• Far vision – accomplished by relaxing ciliary muscle and flattening the lens

ASSESSMENT OF THE EYE4 MOST COMMON PREVENTABLE CAUSES OF PERMANENT VISION LOSS IN DEVELOPED NATION:1) Amblyopia2) Diabetic Retinopathy3) Age related maculopathy4) Glaucoma

Biographical and Demographic data Incidence of cataracts, dry eye, retinal

detachment, glaucoma, esotropia, exotropia increases with age

Hereditary color vision deficits are more common among men (7%) than women (0.5%)

Exploration of Current Manifestations Chief Complaint – most common is a

change or loss of vision; it may also be headache or eyestrain. Chief complaint is often a vague problem as “something is wrong with my eye”.

Symptom analysis • Abnormal Vision – considerations include:• a refractive (focusing) error, such as in the

presence of glare or halos in uncorrected refractive error, scratches on glasses, dilated pupils, corneal edema, or cataract

• interference from lid ptosis (drooping eyelid)

• clouding or interference in the cornea, lens, aqueous or vitreous space

• malfunction of the retina, optic nerve or intracranial visual pathway

• flashing or flickering light- may indicate retinal traction or migraine

• floating spots – may represent normal vitreous body strands or pathologic presence of blood, pigment, or inflammatory cells in the vitreous body

• Diplopia – double vision, may be caused by refractive correction, muscle imbalance, neurologic d/o

DIPLOPIA

RETINAL DETACHMENT

NORMAL VISION

MACULAR DEGENERATION -loss of central vision

GLAUCOMA-loss of peripheral vision

CATARACT-hazy & out of focus

DIABETIC RETINOPATHY-blind spot

• Abnormal Appearance – most common is red eye. Includes growth or lesions, edema, and abnormal position

Diseases causing red eye:• Conjunctivitis – bacterial, viral, allergic, and irritative• Herpes Simplex Keratitis – inflammation of the cornea• Scleritis – inflammation of the sclera• Angle- closure glaucoma – sudden occlusion of the anterior chamber

angle by iris tissue• Adnexal disease – stye, dacryocystitis, blepharitis, lid lesions

(carcinoma), thyroid disease and vascular lesion• Subconjunctival Hemorrhage – accumulation of blood in the potential

space between the conjunctiva and sclera• Pterygium – abN growth of tse that progresses over the cornea• Keratoconjunctivitis sicca – inflammation assoc. w/ lacrimal def.• Abrasions and foreign bodies – hyperemic response• AbN lid fxn - bell’s palsy, opthalmopathy, or lesion that cause

ocular occlusion

Abnormal Sensation

• non-specific complaints include eyestrain, pulling, pressure, fullness or generalized headache.

• Eye pain• Foreign- body sensation• Deeper internal aching• Itching

Dryness, burning, grittiness and mild foreign-body sensation

TearingIncreased ocular

secretions usually indicate viral or bacterial infections and may also be present in allergic and non-infectious irritations.

Abnormal Sensation

Past Health History

• Childhood and infectious Diseases – Ask about systemic disorders with possible ocular sequelae such as diabetes mellitus, retinoblastoma, thyroid disorders, rheumatoid arthritis exposure to STDs such as syphilis and AIDS. Inquire about vaccinations, particularly for measles.

• RETINOBLASTOMA

Major Illnesses and Hospitalizations

Ask about hypertension, multiple sclerosis, myasthenia gravis, and adult onset of thyroid disorders, rheumatoid arthritis, and DM. Inquire also when was the last eye exam and if there is any history of head or eye trauma related to vehicular accidents, sports, injury, or other unintentional events. Ocular diseases and structural problems include refractive errors, strabismus, amblyopia, cataracts, glaucoma, retinal detachment

• Medications- Ask for both prescription and OTC drugs (insulin, oral hypoglycemics, and thyroid replacement hormones, OTC drops, antihistamines and decongestants)

• Allergies – allergies on medications and other substances such as inhalants (dusts, chemicals or pollens) and contactants (cosmetics or pollens

Family Health History – ask about strabismus, glaucoma, myopia and hyperopia, migraine, retinoblastoma, macular degeneration, retinitis pigmentosa, sickle cell anemia and DM

Psychosocial History and Lifestyle – occupational hazards, leisure activities and hobbies, and health mgmt, driving history, exposure to irritating fumes, smoke, or airborne particle, use of safety garments, insufficient lighting, harsh or glaring light, contact sports, outdoor activities such as gardening, hiking, etc.

Review of Systems (ROS)

• inquire about manifestations such as headaches and problems with sinusitis. Ask if such manifestations occur with pain or discomfort, visual changes, swelling, redness, or drainage from the eyes.

PHYSICAL EXAMINATION

• Examination of the eyes include assessment of external structures, using inspection and palpation, extracocular movements (EOMs), visual acuity, and visual fields (peripheral vision)

External eye examination• Eye position – assess eye position for symmetry and

alignment• Eyebrows –inspect for symmetry, hair distribution, skin

condition and movement– Eyelids and Eyelashes for placement and symmetry

• PTOSIS• ENTROPION• EXTROPION

ENTROPION

PTOSIS

Blink response – an involuntary reflex that occurs bilaterally up to 20 times a minute

Eyeballs – palpate for symmetry and firmness.

Lacrimal Apparatus – observe the area for swelling or tenderness. Inspect the area between the lower lid and the nose. Gently palpate the area over the lower orbit rim near the inner canthus.

• Conjunctivae and Sclerae – inspect for color changes, texture, vascularity, lesions, thickness, secretions and foreign bodies.

• Corneal reflex – performed to assess the function of the 5th (trigeminal) cranial nerve.

• Cornea –inspect for abnormalities such as surface irregularities and cloudiness (opacity).– ARCUS SENILIS

» Anterior Chamber – inspect for clarity and transparency with no shadow cast upon the irises.

» Iris and Pupil – assess or test for PERRLA, and direct and consensual response.

» AbN if with photophobia, irregular or unequal pupils (anisocuria)

» AbN pupil may be due to neurologic dse, intaocular inflammation, iris adhesions, ocular meds S/E

Ocular motility/ Extraocular Muscle Test

• provides information about the extraocular muscles; the orbit; the oculomotor, trochlear and abducen nerves; the brain stem connection and the cerebral cortex. Note for speed, smoothness, range and symmetry of ocular movements and observe for unsteadiness of fixation.

NYSTAGMUS

Corneal Light Reflex Test (Hirschberg’s Test)

• – determines eye alignment• STRABISMUS• TROPIA/PHORIA

• ESOTROPIA• EXOTROPIA• HYPERTROPIA• HYPOTROPIA

Cover-Uncover Test

• – assess eye muscle function and alignment for tropia and phoria.

Visual acuity

• Testing visual acuity is the standard and routine method used to determine the clarity of the ocular media (cornea, lens and vitreous) and the function of the visual pathway from the retina to the brain. Traditionally measured with the SNELLEN CHART at a distance of 20 feet.

• Test near vision w/ card or newsprint held 12 to 14 in from the client’s eyes

• Correctives lenses maybe worn if needed• If client becomes familiar with the letters

through repeated exam’n, have the client read the letters backward

• If client can read most of the letter in a particular line but misses 1 or 2, document the visual acuity as 20/40 - 2

SNELLEN CHART

– A 20/20 vision is normal; the patient can read at 20 feet what a person with normal vision can read at 20 feet.

– A visual acuity of 20/60 means that the patient can read at a distance of 20 feet only what a patient with a normal vision can read at 60 feet

Visual acuity

– The patient with myopia has results of 20/30 or greater, signifying that the patient can read at 20 feet only what a person with normal vision can read at 30 feet.

– Hyperopia results are 20/15 or less; that is the patient can read at 20 feet what a person with normal vision can read at 15 feet.

– Legal blindness is defined as 20/200 or less with corrected vision (glasses or contact lenses) or less than 20 degrees of visual field in the better eye.

Visual acuity

TEST FOR COLOR VISION

• ISHIHARA PLATE• Causes: nutritional problems, optic nerve d/o

and problems w/ fovea centralis• Use for screening people seeking a license to

operate a motor vehicle or for employment• Scotoma – central area blindness

Visual fields-Used to evaluate peripheral vision

• Two Methods– Confrontational Method– Perimetry - assesses

peripheral vision, visual fields

PERIMETRY

Internal Eye Examination

• Opthalmoscopic Exam• Direct opthalmoscopy –

hand-held direct opthalmoscope provides a magnified (x15) image of the fundus (posterior portion of the eye), and detailed view of disc and retinal vascular bed

• Indirect opthalmoscopy – provides a stereoscopic picture over a large area of the retina. The light source comes from the hand mounted light– The examiner holds a convex lens in front of the

client’s eye, and through a viewing device attached to the headband, sees inverted reversed image

– It provides a binocular visual perception with depth perception and permits a wider field of view compared with the direct method

Tonometry

• – a method of measuring intraocular fluid pressure with the use of calibrated instruments that indent or flatten the corneal apex.

• Normal intraocular pressure (IOP): 12-20 mmHg

2 types of tonometer• Measures the force

required to flatten the corneal apex by standard amount

• Applanation tonometer

• Measures the amount of tension on the cornea. First, the cornea is anesthetized w/ topical anesthetic drop. While the client sits and looks straight forward, the tonopen is held perpendicular to the cornea and tapped several times directly on the cornea

Hand-held tonometer

Slit-Lamp Examination

• Use to illuminate and examine the anterior segment of the eye under magnification an optical cross section of anterior chamber

AUDITORY SYSTEMAUDITORY SYSTEM

Hearing and balance Hearing and balance problems can reduce the problems can reduce the ability to communicate, ability to communicate, limit social activities, and limit social activities, and hinder the constructive use hinder the constructive use of leisure time. The ears are of leisure time. The ears are a pair of complex sensory a pair of complex sensory organs for both hearing and organs for both hearing and balance. Their location on balance. Their location on either side of the head either side of the head produces binaural hearing, produces binaural hearing, allows the detection of allows the detection of sound direction, and aids in sound direction, and aids in maintaining equilibrium.maintaining equilibrium.

STRUCTURES OF THE EARSTRUCTURES OF THE EAR

External EarExternal Ear Auricle (Pinna):Auricle (Pinna):

outer projection outer projection of the ear of the ear composed of composed of cartilage and cartilage and covered by skin; covered by skin; collects collects soundwaves.soundwaves.

Parts of cartilage that hold the pinnaParts of cartilage that hold the pinna

– Helix – outer rim of the pinnaHelix – outer rim of the pinna– Lobule – inferior portionLobule – inferior portion– Concha – deepest part leading to the ear canalConcha – deepest part leading to the ear canal– Tragus and antitragus – triangular folds of Tragus and antitragus – triangular folds of

cartilage that protect over the entrance to the cartilage that protect over the entrance to the ear canalear canal

STRUCTURES OF THE EARSTRUCTURES OF THE EAR External EarExternal Ear External auditory canal :External auditory canal : lined lined

with skin; glands secrete with skin; glands secrete cerumen, providing protection; cerumen, providing protection; transmits sound waves to transmits sound waves to tympanic membrane.tympanic membrane.

Tympanic membrane (eardrum):Tympanic membrane (eardrum): located at the end of the located at the end of the external canal; vibrates in external canal; vibrates in respond to sound and transmits respond to sound and transmits vibrations to middle ear.vibrations to middle ear.

Thin, translucent, pearly gray Thin, translucent, pearly gray membrane obliquely directed membrane obliquely directed downward and inwarddownward and inward

Middle EarMiddle Ear A. OssiclesA. Ossicles Three small bones: Three small bones:

Malleus (Hammer) Malleus (Hammer) attached to tympanic attached to tympanic membrane, Incus (Anvil), membrane, Incus (Anvil), Stapes (Stirrups)Stapes (Stirrups)

Ossicles are set in motion Ossicles are set in motion by sound waves from by sound waves from tympanic membrane.tympanic membrane.

Sound waves are Sound waves are conducted by vibration to conducted by vibration to the foot plate of the the foot plate of the stapes in the oval window stapes in the oval window ( an opening between the ( an opening between the middle and the inner ear.)middle and the inner ear.)

B. Eustachian Tube: B. Eustachian Tube: connects nasopharynx and connects nasopharynx and middle ear; brings air into middle ear; brings air into middle ear, thus equalizing middle ear, thus equalizing pressure on both sides of pressure on both sides of the eardrum (maintains the eardrum (maintains ventilation and pressure).ventilation and pressure).

C. Mastoid Process:C. Mastoid Process:

bony protruberance behind bony protruberance behind the lower portion of the the lower portion of the pinna. Close to several pinna. Close to several impt cranial structures and impt cranial structures and internal carotid arteryinternal carotid artery

Middle EarMiddle Ear

Inner Ear (Labyrinth)Inner Ear (Labyrinth) A. CochleaA. Cochlea

– Contains Organ of Corti, Contains Organ of Corti, the receptor end-organ the receptor end-organ for hearingfor hearing

– Transmits sound waves Transmits sound waves from the oval window from the oval window and initiates nerve and initiates nerve impulses carried by CN impulses carried by CN VIII (acoustic nerve) to VIII (acoustic nerve) to the brain (temporal lobe the brain (temporal lobe of cerebrum.)of cerebrum.)

B. Vestibule (utricle and B. Vestibule (utricle and saccule)saccule)

C. Semicircular CanalC. Semicircular Canal

ASSESSMENT OF THE EARASSESSMENT OF THE EAR • • OTOLOGIC HISTORYOTOLOGIC HISTORY Biographical and Demographic Biographical and Demographic

DataData Current HealthCurrent Health • • Chief complaint – common Chief complaint – common

chief complaints are as follows: chief complaints are as follows: hearing loss, pain, tinnitus, ear hearing loss, pain, tinnitus, ear drainage, loss of balance, drainage, loss of balance, vertigo, dizziness, nausea or vertigo, dizziness, nausea or vomiting.vomiting.

Symptom analysisSymptom analysis

Hearing loss – may occur suddenly or gradually Hearing loss – may occur suddenly or gradually and can accompany the normal aging process. and can accompany the normal aging process. The loss may be conductive, sensorineural or r/t The loss may be conductive, sensorineural or r/t CNS d/oCNS d/o

The patient may report inability to hear certain The patient may report inability to hear certain words or sounds or that sounds are muffled.words or sounds or that sounds are muffled.

Pain may be perceived as a feeling of fullness in Pain may be perceived as a feeling of fullness in the ear.the ear.

Symptom analysisSymptom analysis

Ear drainage can be bloody Ear drainage can be bloody (sanguineous), clear (sanguineous), clear (serous), mixed (serous), mixed (serosanguineous), or (serosanguineous), or contain pus (purulent). contain pus (purulent). Drainage may also be Drainage may also be accompanied by an odor.accompanied by an odor.

TinnitusTinnitus Loss of balance may be Loss of balance may be

accompanied by vertigo.accompanied by vertigo.

VERTIGO VERTIGO

a sensation of a sensation of motion while the motion while the person is not person is not movingmoving

DIZZINESS –DIZZINESS –feeling of feeling of unsteadiness and unsteadiness and a feeling of mov’t a feeling of mov’t within the head within the head or light or light headednessheadedness

Past Health HistoryPast Health HistoryChildhood and Infectious DiseasesChildhood and Infectious Diseases

Common childhood diseases involving the ears include the Common childhood diseases involving the ears include the following:following:

acute middle ear infections (Otitis media)acute middle ear infections (Otitis media) eardrum perforations resulting from Otitis mediaeardrum perforations resulting from Otitis media complications of ear infections such as chronic Otitis complications of ear infections such as chronic Otitis

media, frequent upper respiratory tract infectionsmedia, frequent upper respiratory tract infections acute and chronic sinus infectionsacute and chronic sinus infections A pneumococcal conjugate vaccine shoes good promise in A pneumococcal conjugate vaccine shoes good promise in

preventing initial ear infection and reducing subsequent preventing initial ear infection and reducing subsequent episodes of acute otitis media in infants and childrenepisodes of acute otitis media in infants and children

Utero exposure to maternal influenza and rubella may Utero exposure to maternal influenza and rubella may result in congenital hearing loss in the childresult in congenital hearing loss in the child

Premature birth may cause hearing problemsPremature birth may cause hearing problems

Infectious diseases with ear Infectious diseases with ear sequelae include mumps, measles, sequelae include mumps, measles, and meningitis. Inquire if the patient and meningitis. Inquire if the patient has been immunized for mumps, has been immunized for mumps, measles, and haemophilus influenza measles, and haemophilus influenza type b (Hib). type b (Hib).

Major Illnesses Major Illnesses and Hospitalizations and Hospitalizations

– – inquire about a history of upper inquire about a history of upper respiratory tract infection, respiratory tract infection, tonsillectomy or adenoidectomy, ear tonsillectomy or adenoidectomy, ear surgery, trauma to the head or ear surgery, trauma to the head or ear such as severe blow or sustained such as severe blow or sustained loud noise exposure or concussion loud noise exposure or concussion from sudden changes in air pressure.from sudden changes in air pressure.

Medications – use of drugs like Medications – use of drugs like aspirin, aminoglycosides, aspirin, aminoglycosides, analgesics, salicylates, quinine, analgesics, salicylates, quinine, chemotherapeutic agents and chemotherapeutic agents and protozoal agentsprotozoal agents

• • Allergies – allergies to Allergies – allergies to medications and to other medications and to other substances, allergies resulting to substances, allergies resulting to stuffiness and congestion stuffiness and congestion (obstructs flow of air b/w the (obstructs flow of air b/w the middle ear and nose so that air middle ear and nose so that air pressure cannot be equalized).pressure cannot be equalized).

• • Psychosocial History – occupational Psychosocial History – occupational hazards, environmental exposure and hazards, environmental exposure and leisure activities and hobbies.leisure activities and hobbies.

50 dB – ordinary speech50 dB – ordinary speech

70 dB – heavy traffic70 dB – heavy traffic

80 dB – uncomfortable to the human 80 dB – uncomfortable to the human ear ear

85-90 dB – exposure to these for 85-90 dB – exposure to these for month or years could cause cochlear month or years could cause cochlear damagedamage

• • Review of Systems (ROS) – ask about Review of Systems (ROS) – ask about the problems with the nose, sinuses, the problems with the nose, sinuses, mouth, pharynx and throat. Has the mouth, pharynx and throat. Has the patient experienced head trauma, loss patient experienced head trauma, loss of balance, dizziness or vertigo of balance, dizziness or vertigo

PHYSICAL EXAMINATIONPHYSICAL EXAMINATION Examination of the ear includes Examination of the ear includes

assessment of hearing acuity, balance and assessment of hearing acuity, balance and equilibrium. equilibrium. – Note size, configuration, and angle of Note size, configuration, and angle of

attachment to the head. Note whether attachment to the head. Note whether ears protrude if so the degree of ears protrude if so the degree of protrusion, the color of the skin of the protrusion, the color of the skin of the ears . Note any lumps, lesions, cysts. ears . Note any lumps, lesions, cysts. Palpate and manipulate the pinna to Palpate and manipulate the pinna to detect, tenderness, nodules or tophi detect, tenderness, nodules or tophi

Inspection and palpation of auricle, Inspection and palpation of auricle, periauricular area, and mastoid areaperiauricular area, and mastoid area

Examination of the ear canalExamination of the ear canal 2 Methods:2 Methods:

– Direct observation Direct observation – Otoscopic examinationOtoscopic examination

Otoscope – a device that Otoscope – a device that consist of a handle, a light consist of a handle, a light source, magnifying lens, source, magnifying lens, and an attachment for and an attachment for visualizing the earcanal and visualizing the earcanal and ear drumear drum

Pneumatic device – bulb to Pneumatic device – bulb to instill air to the eardrum to instill air to the eardrum to test its mobility and test its mobility and integrityintegrity

C. Tests for Auditory AcuityC. Tests for Auditory Acuity

– – assessment assessment of the middle of the middle and inner ear and inner ear for hearing. for hearing.

• • Whispered Whispered voice or voice or ticking watch ticking watch testtest

C. Tests for Auditory AcuityC. Tests for Auditory Acuity

• • Weber testWeber test

C. Tests for Auditory AcuityC. Tests for Auditory Acuity

• • Rinne TestRinne Test

Tests for Vestibular AcuityTests for Vestibular Acuity

Romberg testRomberg test Test for Test for

NystagmusNystagmus Caloric test / Caloric test /

Oculovestibular Oculovestibular reflex testreflex test

LABORATORY TESTSLABORATORY TESTS

Blood testBlood test CulturesCultures Tests for Presence Tests for Presence

of Cerebrospinal of Cerebrospinal FluidFluid

Tissue SpecimensTissue Specimens

S E N S E S