Eye Structure & Physical Assessment

Physical Assessment Overview

• Includes assessing eye structure and visual acuity, ears and hearing, mouth, throat & nose, thorax and lungs, and breasts and lymphatic vessels.

Eye Assessment - Overview

• The eye is the organ of the visual system that detects light, converts it into electrochemical impulses in neurons, and interprets visible light information.

External Eye Structures

• Eyelids: Both eyelids contain a tarsal plate with Meibomian glands and join at the medial and lateral canthi.
• Sclera: It is a thick, protective outer coat of the eye that underlies the conjunctiva, usually white and opaque, and its inflammation is very painful and associated with vision loss.
• Episclera: Covers the anterior sclera, lacks the scleral bluish discoloration, is continuous with the cornea, and its inflammation is not typically painful and does not change vision.
• Limbus: It is the corneal-scleral junction.
• Iris: It filters light, is a muscular aperture controlling pupil size, and contains the stroma and pigmented epithelium layers.
• Pupil: It is a central hole or shutter within the iris and its size is controlled by iris constriction (Miosis) and relaxation (Mydriasis), and determines the amount of light exposure on the retina.
• Conjunctiva: thin, vascular tissue that covers the inner lid lining (palpebral) and sclera (bulbar) with 60% focusing image.
• Cornea: It is the transparent front refractive window of the eye.
• Macula and Fovea: Fine central vision area at the posterior pole including the oval depression at the center of macula.

Extraocular Muscles

• Innervated by CN3,4,6 and enable eye movement.
• Medial Range of Motion: Medial Rectus (Cranial Nerve III)
• Lateral Range of Motion: Lateral Rectus (Cranial Nerve VI)
• Upward Range of Motion: Superior Rectus (Cranial Nerve III) & Inferior Oblique (Cranial Nerve III)
• Downward Range of Motion: Inferior Rectus (Cranial Nerve III) & Superior Oblique (Cranial Nerve IV)

Internal Eye Structures

• Anterior Chamber: Located between the cornea and iris and contains aqueous humor.
• Posterior Chamber: Located between the iris and zonulae and contains aqueous humor.
• Ciliary Body: Produces aqueous humor and suspends lens by zonulae.
• Aqueous Humor: Clear fluid filling the anterior and posterior chambers; produced by the ciliary body, passes through the pupil, and drains via the trabecular meshwork.
• Vitreous Cavity: Large space (4.5cc) between the lens and retina that contains transparent gel (vitreous humor).
• Aqueous Outflow Angle: Intersection of cornea, iris, and ciliary body and its blockage results in glaucoma.
• Choroid: Vascular pigmented tissue between the sclera and retina and vascular supply for outer Retina
• Avascular structures: Lens, anterior vitreous, and cornea endothelium.

Intrinsic Eye Muscles

• Ciliary Muscle: Innervated by CN III, constricts ciliary body and relaxes tension on the lens for eye accommodation.
• Sphincter Pupillae: Innervated by CN III and constricts pupil.
• Dilator Pupillae: Innervated by sympathetic nerves and dilates pupils.

Eye Muscle Deficit:

• CN3 Palsy: Lateral & downward deviation, ptosis
• CN4 Palsy: Upward deviation
• CN6 Palsy: Medial deviation

Eye Examination Recommendations

• Under 40 Years: every 3-5 years without family history of hypertension, diabetes, or eye disease.
• 40 Years and Up: every 2 years
• Procedure: Let the client wear glasses during the examination, and check external eye structures, accommodation, visual fields, extraocular muscles, and visual acuity.

Visual Acuity Test

• Assesses sharpness and clarity of vision at various distances.
• Procedure: Light Perception, Hand Movement Test, Counting Fingers
• Normal findings: Denominator of 40 or more on Snellen-type chart with corrective lenses, 20/20 vision on Snellen-type chart, Emmetropia - normal vision
• Abnormal findings:
• Myopia (nearsightedness): Difficulty seeing distant objects clearly.
• Hyperopia (farsightedness): Difficulty seeing close objects clearly.
• Presbyopia: Age-related loss of the ability to focus on nearby objects.
• Glaucoma: Eye pressure damages optic nerve, leading to vision loss.
• Retinal Detachment: Retina pulls away from the back of the eye, causing vision loss.
• Astigmatism: Irregular cornea shape causing blurred vision.
• Papilledema: Swelling of optic disc due to increased intracranial pressure.
• Optic Atrophy: Damage to the optic nerve, leading to vision loss.
• Diabetic Retinopathy: Damage to retina blood vessels caused by diabetes.
• AMD (Age-related Macular Degeneration): Deterioration of the macula causing central vision loss.

Visual Field Test

• Measures the entire area you can see when your eyes are fixed on a central point.
• Definition: Helps to evaluate the range of your peripheral (side) vision and detect any blind spots or vision loss.
• Normal findings: Peripheral field - 90° angle (temporally), upward field vision - 50° (orbital ridge), downward field vision - 70° (cheekbone), nasal field vision - 50° (nose)
• Abnormal Findings:
• Smaller than normal possible glaucoma.
• Loss in specific fields (e.g., left superior quadrant anopia, right homonymous hemianopia).
• Unilateral/bilateral blindness: Loss of vision in one or both eyes.
• Anopsia/anopia: General vision loss or blindness.
• Bitemporal hemianopia: Loss in the outer half of both visual fields.

Visual Inspection

• Detects disease or abnormalities that may affect the eyes or vision.
• Eyes aligned and symmetrical, with no squinting, tilting, or asymmetry.
• Normal Findings: Eyelids display 15 - 20 involuntary blinks per minute and demonstrates bilateral blinking.
• Abnormal findings:
• Ptosis is drooping eyelids caused by muscle weakness or nerve damage.
• Entropion: Eyelid turns inward, causing eyelashes to irritate the eye.
• Ectropion: Eyelid turns outward, leading to dryness and irritation of eye.
• Trichiasis: Eyelashes growing inwards towards the eye, causing irritation and discomfort.
• Abnormal findings:
• Dacryocystitis: Swelling, redness, or tenderness, indicating possible blocked tear ducts.
• Abnormal findings:
• Allergic Conjunctivitis with results in itchy, red, watery eyes.
• Viral Conjunctivitis often associated with other cold symptoms, watery discharge, red eyes,
• Bacterial Conjunctivitis causing yellow/green discharge, red eyes.
• Episcleritis: Inflammation of the episclera with localized redness and mild discomfort.
• Jaundiced sclera indicating liver issues.
• Pale sclera indicating anemia.
• Reddened sclera indicating inflammation.
• Lesions or nodules.
• Abnormal Findings:
• Arcus senilis: A gray ring around the cornea (possibly high cholesterol).
• Keratoconus: Bulging cornea causing distortion.

Pupils

• Black, equal size (3-7 mm), round, smooth border in its normal state.
• Abnormal findings:
• Cloudiness - cataracts
• Mydriasis - dilated pupils
• Miosis - constricted pupils
• Anisocoria - unequal sizes pupils
• Bulging iris - glaucoma

Pupillary Reaction Test

• Definition: Assesses the neural pathways responsible for pupillary light reflexes and detects potential neurological problems.
• Direct Response: Refers to the constriction of the pupil that is directly exposed to light.
• Consensual Response: Refers to the constriction of the opposite, non-illuminated pupil when the light is shined on the first pupil.
• Normal Findings: Both pupils constrict with light (direct and consensual).
• Abnormal Findings:
• Unequal or sluggish responses, absent response.
• Horner Syndrome: Smaller pupil, drooping eyelid, lack of sweating (nerve damage).
• Unilateral Dilated Pupil: Potential brain injury or increased pressure.
• Definitions:
• Esotropia: One or both eyes turn inward.
• Exotropia: One or both eyes turn outward.
• Hypertropia: One eye turns upward.
• Hypotropia: One eye turns downward.

Cardinal Gaze

• Tests the movement and coordination of the extraocular muscles and assesses for conditions such as strabismus or nerve palsies.
• Normal Findings: Eyes move in unison with coordinated, parallel movements.
• Abnormal Findings:
• Eyes fail to follow the finger in certain directions, or one eye fails to follow.
• Strabismus - cross - eye
• Nystagmus - rapid involuntary rhythmic eye movement. Other than at end point may indicate neurologic impairment

Accommadation Test

• To test the eye's ability to change focus and assess the health of the accommodation system.
• Normal Findings: Pupils constrict for near object, dilate for distant object, and converge as the object moves toward the nose.
• Abnormal Findings: One or both pupils fail to constrict, dilate, or converge.

Corneal Light Reflex (Hirschberg Test)

• Used to assess the alignment of the eyes and detect strabismus (misalignment of the eyes).
• Normal Findings: Symmetrical reflection indicating proper ocular alignment.
• Abnormal Findings:
• Uneven corneal light reflections, indicating misalignment (strabismus).
• Strabismus - asymmetry misalignment or involuntary eye movements.

Convergence

• To assess the eye's ability to work together when focusing on a close object, which is important for binocular vision.
• Normal findings: Pupils converge as the object moves toward the nose.
• Abnormal findings: One or both pupils fail to converge.

Refraction

• Definitions: Measured in Diopters & refers to the bending of light rays
• Cornea: Provides 66% of the eye's focusing power (fixed focusing power)
• Crystalline lens: Provides 33% of the eye's focusing power, changing shape to focus on objects (accommodation)
• Refractive Power: Reciprocal of focal length (measured in meters)
• Example:
• 1 diopter lens has a focal length of 1 meter
• 2 diopter lens has a focal length of 0.5 meters
• Emmetropia (Normal Vision): The eye's focusing power is perfectly matched to the globe length with the image focused precisely on the retina
• Myopia (Nearsightedness):
• Causes: Autosomal Dominant inheritance and environmental factors like prolonged reading or close work.
• Mild Myopia (-0.5 to -2.0 D) typically appears between 5-8 years.
• Moderate Myopia (-2.0 to -5.0 D) usually develops between 8-14 years.
• Severe Myopia (<-6.0 D) occurs between 20-28 years.
• Pathophysiology:
• Light rays focus in front of the cornea
• Distant objects are blurred
• Correction: Concave lenses (divergent, minus power)
• Degrees of refractive error:
• Mild Myopia (> -1.5 Diopters)
• Moderate Myopia (-1.5 to -6.0 Diopters)
• High Myopia (< -6 Diopters)
• Severe Myopia (< -8 Diopters), often associated with conditions like Glaucoma, Retinal detachment, and Macular degeneration
• Hyperopia (Farsightedness):
• Normal in infants (+0.50 to +2.50 Diopters) and vision usually normalizes by 5-8 years
• Light rays focus behind the cornea and near objects are blurry
• Correction: Convex lenses (convergent, plus power)
• Astigmatism: Results from a non-spherical corneal surface where certain areas are steeper, causing blurry vision at any distance.

Ear Anatomy

• Outer Ear (External Ear):
  • Auricle (Pinna): The fleshy, visible part of the ear that protrudes from the side of the head is made of elastic cartilage covered by skin and collects and funnels sound waves towards the ear canal.
  • External Auditory Canal (Ear Canal): a bony and cartilaginous tube-like structure that leads from the auricle to the eardrum; guides and helps amplify sound waves.
• Middle Ear:
  • Tympanic Membrane (Eardrum): A thin, cone-shaped membrane that separates the external ear from the middle ear and transmits sound vibrations to the middle ear.
  • Ossicles: Three small bones (malleus, incus, stapes) that amplify the sound vibrations from the eardrum and transmit them to the inner ear.
• Inner Ear:
  • Cochlea: A spiral-shaped organ that contains sensory cells that convert sound vibrations into electrical signals sent to the brain via the auditory nerve.
  • Vestibular System: Includes the semicircular canals and the vestibule, which are involved in maintaining balance and spatial orientation.
  • Semicircular Canals: Three looped structures that detect rotational movements of the head.
  • Vestibule: Contains the utricle and saccule, which detect linear acceleration and gravity contributing to balance.
  • Eustachian Tube: A canal that connects the middle ear to the throat, helping equalize pressure;

Hearing

• Transmitted through malleus, incus, and stapes in the middle ear.
• Types of hearing loss:
• Conductive Hearing Loss: Transmission of sound through external and middle ear limited, bypasses air conduction and allows bone conduction
• Perceptive/Sensorineural Hearing Loss: Dysfunction in the phase where cochlea and auditory nerve.

Abnormal findings in hearing

• Sudden Hearing Loss with Otitis Media in one ear.
• Sudden Sensorineural Hearing Loss(SSHL) with require medical treatment immediately.
• Vertigo: (Client feels spinning) which makes him lose balance in his body or Objective Vertigo (room feels spinning).

Examination and health practices

• Swimmer’s ear (otitis ear external or external otitis);
• Gradual hearing loss or presbycusis common for old age people between age 50;
• Excessive earwax production
• Check history and any sign of skin cancer or trauma

Inspection

• Normal auricle, the tragus, and lobule, Tymapnic membrane (ear drum); should be visible and clear view. If obstructed, could have Buildup of cerumen , polyp or even tumor Tumpanic membrane with red, bulging, could indicate inner ear infection. Or yellowish from bubble.

Hearing test

Normal air conduction should be clear sound; if is, have poor earing it may lead to poorer ear If rinne test is not normal may indicate poor air conduction.

Inspection Of mouth

• For any abnormalities as cancer or infection; Check and ensure symmetry

Physical throat inspection.

Look for

• Swelling
• Color Look for enlarged thyroid

Sinuses

Are symmetrical with clear nasal; if it does not have smell could be indicate of smell distortion If have pain while breathing could indicate of sinuses infection

Early Signs of cancer

Acronym CAUTIONUP should be utilized during examination or patient review. Change in bowel or balder Lesion that not heel Unusual bleeding Thinking or lump in throat Indigestion occur with difficulty Obvious wart Nagging cough Unexplained reason or weight Pernicious reason

Mouth and throat

Is inspected by looking and abnormalities inside and tissue

Palpation is performed with glove and sterile

• Checking tongue
• Teeth
• Gums
• Salivary gland to see if there are tenderness, abnormalities

Throat

Located in throat area

• Nasopharynx
• Oropharynx
• Laryngopharynx

Tonsils are located in the back of the throat.

They are made of Palatine Lingual Pharyngeal

Nose consist of

Cartllage,bone divided by nasal sptum Consists of nasal passing ways

Mouth care

Smell and health may diminish or reduce due Medicatiol in older age cause

Thyroid

If having hard time difficulty Consult and speech therapy

Test that indicate ear disorder

• Balance
• Mobility If so then may be indicated cancer

Mouth

A good dental teeth care can make sure no teeth decay or mouth problem

Abnormal finding of lips

• Discolored , change to breath or foul color , and sign of disorder

Tapping nose is normal

Breathing

Respirations for normal; look for no skin problem, check the Skin for oxygen status

Thoractic or lunch shape

Diaphragm

Prime mover of inflation Contracts Elevates