Perceptual Disturbances
Perceptual Disturbances
Perceptual Disturbances
Medical Surgical Nursing - Stimulation of the photoreceptors to bipolar cells to ganglion cells
- Axons in optic tracts travel to thalamus, synapse with neurons (optic
TOPIC: Perceptual Disturbances (EENT Conditions) (Part 1) radiation)
- Visual fields overlap considerably (slightly different view in each eye)
ANATOMY, PHYSIOLOGY AND FUNCTIONS OF THE EYES
REFRACTION
- Contain 70% of body’s sensory receptors
- Primary functions - Bending of light rays as they pass from one medium to another medium
o Encode patterns of lights - Accommodation- Focusing of image on a single point
o Carry coded information to brain - Convergence- Medial rotation of eyeballs that allows focusing of the image
on retinal fovea of each eye
ACCESSORY STRUCTURES OF THE EYE
SUBJECTIVE DATA COLLECTION FOR THE EYE
- Eyebrows, Eyelids, Eyelashes
- Conjunctiva Category Questions to ask Rationale/Significance
- Lacrimal Apparatus during the health
- Extrinsic eye muscles history
Family History Do you have family Many eye disorders are
Eyebrow- Perhaps the most significant role of the eyebrows is to enhance facial members with a history genetically transmitted
expression, aiding in non-verbal communication. They also help keep of diabetes?
perspiration out of the eye and shields the eye from glare Hypertension?
Cataracts? Glaucoma?
Eyelids- Formed primarily by the orbicularis oculi muscle covered with skin, the Blindness? Diabetes
eyelids protect the eye from foreign bodies and block light when closed to allow mellitus?
for sleeping. Periodic blinking also helps moisten the eyes with tears and warm
out debris. Do any family
members wear glasses
Palpebral Fissure: This is the opening between the lids or contact lenses? Is
their vision corrected
Tarsal Glands- These glands which lie along the thickened area at the edge of with the lens?
the eye secretes oil to slow the evaporation of tears and help form a barrier seal Patient’s general How could you Some metabolic
when the eyes are closed health describe your general disorders are precursor
health? to eye disorders, such
Conjunctiva: Is a transparent mucous membrane that lines the inner surface of What health problems as diabetes and
the eyelid and covers the anterior surface of the eyeball (except for the cornea). do you currently have? hypertension.
It secretes a thin mucous film to help keep the eyeball moist. It is very vascular How are they treated? Assess for ocular
which becomes apparent when eyes are “bloodshot” a result of dilated vessels in What health problems effects of systems
the conjunctiva have you had in the medication.
past? Assess preventive
Eyelashes- These hairs along the edges of the eyelids help keep debris out of Have you ever had practices.
the eye. Touching the eyelashes stimulates the blink reflex. trauma to your eyes?
What medications do
Lacrimal Gland- This small gland secretes tears that flow onto the surface of the you take?
conjunctiva. Tears clean and moisten the eye’s surface and also deliver oxygen How often do you have
and nutrients to the conjunctiva. Furthermore, tears contain a bacterial enzyme eye examinations?
called lysozyme that helps prevent infection. When was the last time
you had an eye
Lacrimal Punctum: This is a tiny pore through which tears drain into the lacrimal examination?
canal and the nasolacrimal duct
Visual acuity Do you wear glasses or Any of these signs and
Nasolacrimal Duct- This passageway carries tears into the nasal cavity (which contact lenses? symptoms could
explains why crying or watery eyes can cause a runny nose. Have you had any indicate visual
changes in vison such disorders/disturbances
Vitreous Humor- the vitreous humor is the transparent gel that gives the as difficulty seeing
eye its shape distances, difficulty
Ciliary Body- The ciliary body makes the fluid inside the eye. It also enables seeing close up,
the lens of the eye to focus on objects at various distances. difficulty seeing at
Lens- The lens is clear part that receives the light that enters they eye. It night?
then bounces off this light to the back of the eye. Do you see things
Iris- The iris is the colored part in front of the eye. It helps screen and double?
Do you have clouded
control the amount of light that enters the eye.
vision?
Cornea- The cornea is the transparent film-like part that enables the eye to
Do you see halos
focus to images so they do not look blurred around lights?
Sclera- It is the white part of the eye. It is made of tough material that Does it look like you
protects the inside of the eye. are looking through a
Choroid- It is the middle layer of the wall of the eye. It is filled with blood veil or web?
vessels that bring oxygen and nutrients to the eye. Is there sensitivity to
Retina- It receives the light from the lens. It is made up of rods and cones. light?
The rods let the eye sense light while this cone helps identify color. Is there pain? Itching?
Blood Vessels- Carry blood to and from the eye. They transport oxygen and Tearing? Burning?
nutrients to the eye. Do you have
Optic nerve- Transmits electrical impulses or nerve messages from the eye headaches? If so, what
to the brain. are the precipitating
events?
THE PHYSICAL ASSESSMENT OF THE EYES - Abnormal eye movements
- Watering or irritation
- Visual field, acuity testing - Changes in vision
- Vision assessment
o Snellen chart AGE RELATED CHANGES IN THE EYE
o E chart
- Inability to accommodate
o Rosenbaum chart
- Cataract development
o Confrontation chart
- Alteration in color perception
- Eye movement assessment
o Cardinal fields, corneal light reflex ASSESSING THE EYES
o Assess convergence
- Diagnostic tests
OBJECTIVE DATA COLLECTION FOR THE EYE o CT, MRI
o Fluorescein, angiography
CATEGORY PHYSICAL POSSIBLE o Refraction, retinoscopy, refractometry
EXAMINATION ABNORMAL
FINDINGS FINDINGS/CAUSES o Tonometry
Visual Acuity Normal vision is 20/20 Hyperopia, myopia, o Ultrasonography
presbyopia, blurred or
cloudy vision DIAGNOSTIC TEST FOR THE EYES
Possible causes:
refractive error, opacity 1. Eye culture
or disorder of pathway 2. Digital imaging
Visual Fields Full peripheral fields Peripheral field loss 3. Optical coherence tomography (OCT)
Muscle Balance and Movement in all six Nystagmus 4. Fluorescein or indocyanine green angiography
Eye movement cardinal fields of gaze Inability to move to all 5. Electroretinography
Corneal light reflex test six fields can indicate 6. Ultrasonography
(light is at the same cranial nerve 7. Imaging Test:
place on both pupils) impairment a. X-ray
Cover test steady gaze Asymmetry could mean b. CT-Scan
muscle weakness
Drifting eye indicates THERAPEUTIC MEASURES FOR THE EYE AND VISION
muscle weakness
Pupillary reflexes Pupillary light reflex Dilated, fixed or 1. Regular eye examination
accommodation constricted pupils - Eye care providers include the ophthalmologist and optometrist (optician)
Absence of constriction 2. Eye Hygiene
or convergence 3. Nutrition for the Eyes
External structures Inspection and Ptosis (drooping of - Eye disorders related to inadequate vitamin intake include corneal damage
palpation of eyebrows, eyelid) usually and night blindness form lack of Vitamin A and optic neuritis as a result of
orbital area, eyelids, indicates nerve vitamin B deficiency
palpebral fissure, dysfunction 4. Eye safety and prevention of Injury
medial canthus, irises, Opaque whitening of
- Many of these injuries could be prevented with education and
corneal clarity, anterior outer rim of cornea can
implementation of safety measures
chamber indicate arcus senilus
Corneal opaqueness EYE SAFETY AND INJURY PREVENTION
can be from cataract or
trauma
TO PROTECT FORM Use these eye safety measures
Foreign objects Water safety goggles
Avoid mowing over rocks or sticks
MUSCLE BALANCE AND EYE MOVEMENT Always wear safety goggles when
using lawn edging yard devices
- Confrontation Chemical splashes Use splash shields when working
- Corneal light reflex with chemicals such as cleaning
solution or body fluids
- Cover test
Close eyes to avoid getting haor
o Normal spray in them
o Esotropia- eyes pointing inward Corneal lens abrasions/infections Follow manufacturers or eye care
o Exotropia- eyes deviates outward from contact lenses professional directions for length of
o Hypotropia- downward turn of the eye use and cleaning procedure
o Hypertropia- upward turn of the eye Do not overwear lenses
Ultraviolet light Wear ultraviolet protected
Pupillary assessment External Eye Internal eye sunglasses when outdoors
Assessment assessment Instruct patients to wear sunglasses
- Size, shape, - Eyelids, puncta, - Ophthalmoscope, with side shields after administration
equality with light conjunctivas, red reflex, lens of mydriatics
- Accommodation sclera, assess and vitreous body Wear a hat to shield sun
corneal sensitivity Visual deficits in adult with corrective Update prescription of glasses yearly
lenses Glasses should fit properly, be calm,
and be free of scratches
HEALTH ASSESSMENT INTERVIEW Eye strain from computer usage The position of the bottom of the
monitor should be 20 degrees below
Analyze issue the line of sight and should be
positioned 13 to 18 inches from the
Observe for: eyes
The light in the room should prevent
- Squinting glare
Increase the font size on the screen Complementary therapies
if letters appear to small
If dry eyes are a problem while using - Frequent eye irrigations
a computer, adjust the monitor to a - Soaking lids with warm saline compress prior to cleansing
lower level so the eyes do not have
open as wide, which increases Nursing Care
evaporation
- Education
Eye injury from sports Wear protective eyewear with
polycarbonate lenses - Preventing spread
Wear facemasks or helmets while - Diagnoses, outcomes, and interventions
participating in ant high contact or o Risk for infection
high impact sports o Risk for impaired vision
- Continuity of care
o Teach home care, typically managed in community
NURSING CARE OF THE PATIENTS WITH EYE DISORDERS o Avoid activities like excessive reading
EYE DISORDERS ALTERATIONS IN REFRACTION
8. THE PATIENT WITH GLAUCOMA 9. THE PATIENT WITH AGE RELATED MACULAARR DEGENERATION
- Optic neuropathy - Cause unknown, but associated with:
- Gradual loss of peripheral vison o Aging
- Increased intraocular pressure o Smoking
- Incidence and risk factors o Race
o Affects 2.7 million people over age 40 in the US o Genetic factors
o Leading cause of blindness worldwide
Pathophysiology
o Age
o Race - Non-exudative macular degeneration
o Gradual detachment of pigment
Pathophysiology
o Epithelium in small areas
- Open-Angle Glaucoma o Caused by accumulation of drusen
o Normal anterior chamber angle between iris and cornea o Sensory function of the macula impaired
o Outflow of aqueous humor relatively obstructed o Can progress to exudative stage
Manifestations: Manifestations
- Blurred/distorted central vision (unilateral) - Risk factors
- Intact peripheral vision o Aging
o Myopia
Interprofessional care
o Aphakia
- Diagnosis
Interprofessional care
o Vision and retinal examination
o Amsler grid - Inflammation treatments
o Fluorescein angiogram o Cryotherapy, cryopexy
- Treatments o Super-cooled probe
o High dose antioxidants o Laser photocoagulation
o Zinc - Pneumatic retinopexy
o Photodynamic therapy - Scleral buckling
- Laser surgery
- Photodynamic therapy Nursing care
- Prompt recognition
- Priorities of care
- Rapid referral for ophthalmologic evaluation
o Early identification and treatment
- Slowly progressive AMD
- Diagnoses, outcome and evaluations
o Heling patient, family adapt
o Ineffective tissue perfusion: retinal
o Anxiety
10. THE PATIENT WITH DIABETIC RETINOPATHY
- Continuity of care
o Limitations before or following repair
- Capillaries of the retina become sclerotic
o Activity restrictions, eye shield
- Insufficient oxygen and nutrients transported to retina
o Early manifestations
Pathophysiology and manifestations
12. THE PATIENT WITH RETINITIS PIGMENTOSA
Background retinopathy- - Retinal atrophy and loss of function
- Earliest stage, in which microaneurysms form on the retinal capillary walls - Progresses from periphery to central region
o These microaneurysms may leak blood into the central retina or - Inherited
macula - Can be associated with other genetic defects
o If the leakage causes edema, the patient my notice a decrease in color - No effective treatment
discrimination and visual acuity - Manifestations
o Difficulty with night vision
Non-proliferative retinopathy Often noted during childhood
- Retinal edema or small hemorrhage o Slow loss of visual fields
- Few symptoms might occur o Photophobia
o Disrupted color vision
Proliferative retinopathy
o Tunnel vision
- Large areas of retinal ischemia
o Blindness
- Neovascularization- prone to rupture
- Retinal edema, hemorrhage into the vitreous body Nursing care
- Increased risk for retinal detachment
- Providing information
Interprofessional care - Referral for genetic counselling
- Yearly ophthalmologist exams
- Blood glucose levels and blood pressure 13. THE PATIENT WITH AN ENUCLEATION
- Laser photocoagulation - Surgical removal of an eye
o Ranibizumab (lucentis) improves laser treatment for patients with - Necessitated by trauma, infection, glaucoma, intractable pain, or
macular edema malignancy
- Education - Complications
o Regular exams o Hemorrhage
o Report changes quickly o Infection
o Incurable, slowed with aggressive self-management
Enucleation:
11. THE PATIENT WITH A RETINAL DETACHMENT - The entire eye, including the globes, is removed but the orbital contents are
- Separation of the retina from the choroid left in place.
- Causes of detachment - Globe is removed
o Trauma - Conjunctiva and eye muscles are sutured to a round implant
o Shrinkage of vitreous humor - A prosthesis is fittedNursing care
o A break or tear in the retina - Teaching
- Psychologic support
Pathophysiology and manifestations - Observation for complications
- Detached area
o Can rapidly increase in size
o Can cause permanent vision loss unless contact is reestablished
- Manifestations
o Floaters
o Lines of flashes of light
o Curtain sensation
o No pain; eye appears normal