Eye Diseases and Visual Emergencies - Study Flashcards
Age-related Macular Degeneration (AMD)
Definition and core issue:
AMD causes central vision loss with preserved peripheral vision. Patients may lose the ability to recognize faces up close while still having side (peripheral) vision.
Not a medical emergency in the acute sense; it progresses over time (age-related).
Visual description and examples:
Central distortion/absence of chin example: in AMD you may notice central vision loss; peripheral vision remains. Anecdote used: a friend’s chin disappearing from view, then returning as you move your gaze.
Contrast with ocular migraine (temporary) where vision returns; AMD vision loss tends to be persistent.
Personal anecdote: misdiagnosis as AMD; retina specialist corrected to myopic degeneration (see below).
Key terms and differential ideas:
Myopic degeneration: associated with high myopia (elongated eyeball) leading to similar hemorrhagic/degenerative changes; can mimic AMD.
Assessment considerations:
Primary issue is central vision; peripheral vision should be tested to confirm central loss.
In class: tests examined central (focal) vision versus peripheral vision:
Central: cranial nerves and convergence assess focal/center vision.
Peripheral: assess field of view; check ability to see around the periphery and along the face.
Practical observation: as central vision worsens, it becomes hard to identify items or read; use of larger fonts helps.
Prevention and treatment expectations:
No definitive prevention strategy beyond general eye health; age-related process.
Treatments exist to slow progression, particularly for the wet form:
Eye injections (anti-VEGF therapy) to reduce abnormal blood vessel growth and leakage.
Injection schedule commonly starts with more frequent dosing.
Dry AMD: no cure; management focuses on monitoring and supportive care.
Impact on daily living and safety:
Driving safety at risk due to central vision loss; compensatory strategies and safer driving with reduced central vision.
Environmental adaptations: brighter lighting, high contrast materials, and magnification as needed.
Prevention and lifestyle considerations:
UV protection: sunglasses with good polarization to reduce UV exposure.
Diet and supplements: eye vitamins and a diet rich in fruits/vegetables and antioxidants (Vitamin A, etc.) may support eye health.
Connections to broader eye health topics:
Wet vs Dry AMD: wet AMD is more treatable with injections; dry AMD is more about slower progression and supportive care.
AMD relevance to strokes/perfusion: later sections connect central vision loss with broader cerebrovascular health in perfusion topics.
Practical teaching points for nurses:
Recognize that AMD is not an acute emergency; focus on safety, vision aids, and ensuring patient can navigate safely.
Counsel on driving safety, lighting, and readability (larger font, high contrast).
Reinforce importance of follow-up with retina specialists for injections and monitoring.
Glaucoma
What glaucoma is:
Increased intraocular pressure (IOP) that damages the optic nerve.
Assessed via IOP tests (e.g., puff tests at the eye doctor) and peripheral vision testing.
Types and terminology:
Chronic glaucoma (open-angle): slow, insidious progression; many patients do not notice until late.
Acute glaucoma (closed-angle): sudden rise in IOP with rapid vision loss; an ocular emergency.
Note: textbooks may use “open-angle vs closed-angle,” but the speaker uses chronic/open-angle and acute/closed-angle terms.
Acute glaucoma presentation and action:
Symptoms: sudden eye pain, nausea, vomiting, headache, and a rapid loss of peripheral vision.
Immediate action: seek medical attention urgently (emergency care center such as Callahan Eye Foundation or Eye Foundation).
Immediate management: often eye drops including beta-blockers to reduce IOP.
Chronic glaucoma management:
Daily eye drops to lower IOP; common categories include beta blockers and prostaglandin analogs; many regimens use combination products (e.g., Timolol-based with prostaglandin analog).
Demonstration and technique for eye drops:
Step 1: wash hands.
Step 2: inform patient what you will do.
Step 3: instill into the conjunctival sac (do not touch the eyeball with the bottle tip).
Step 4: apply gentle pressure to the lacrimal area for about 30 seconds to minimize systemic absorption and hypotension risk.
Systemic effects: absorbed beta blockers from eye drops can lower blood pressure; may cause dizziness, especially with position changes.
Practical patient teaching: ensure good lighting for administration; avoid touching the dropper to eyes; apply pressure to prevent systemic effects.
Safety and functional adaptations:
Drive safety with vision changes; provide guidance on safe navigation and use of compensatory head turns.
Open-angle vs closed-angle terminology to understand risk and treatment implications.
Post-care and education:
Ensure patients have safe driving plans and understand when to seek urgent care for vision changes.
Cataracts
What cataracts are:
Opacity of the lens causing scatter of light and glare; light disperses rather than focusing properly, leading to blurred vision and halos around lights.
Not an emergency; very common with aging; many people eventually require cataract surgery.
Symptoms described:
Blurry vision despite good visual acuity on some charts.
Halos around lights, glare, especially at night; sensitivity to headlights.
Difficulty driving at night due to glare and halos.
Personal perspective from the speaker:
Recalled having cataracts at age ~40 and undergoing lens replacement with an intraocular lens (IOL).
Treatment:
Surgical removal of the cloudy natural lens and implantation of an artificial lens (IOL).
Pre-operative considerations:
If wearing contact lenses, avoid them for a predetermined interval before surgery.
Reason: reduce infection risk during surgery.
Post-operative care and regimen:
Eye drops: usually a regimen of antibiotic and steroid drops; some patients receive a single combination drop; others may use separate drops for antibiotics and steroids.
Schedule example after cataract surgery:
Day 1: every $3$ hours
Day 2: every $4$ hours
Days 3–5: every $4$ hours for $2$–$3$ days, then taper.
Post-operative precautions:
Do not wear contacts for a period after surgery.
Eye patch at night to protect the eye; avoid rubbing the eye.
Avoid bending over or heavy lifting; maintain proper ergonomics; avoid sleeping on the operated side until cleared.
Avoid contact sports or activities that risk trauma to the eye for a period (roughly two weeks).
Recovery and outcomes:
Vision typically improves significantly after cataract removal and IOL implantation.
Some patients may not be candidates for surgery due to medical reasons; surgery remains the goal for restoring vision where possible.
Retinopathy and Retinal Conditions
Diabetic retinopathy (retinopathy):
Not an acute eye emergency; caused by diabetes; no cure once established, but progression can be slowed with good diabetes control.
Management focus: blood sugar control, regular eye exams, lifestyle factors.
Visual aids and adaptations for low vision: good lighting, high contrast, larger fonts; dark mode on devices may improve readability; magnifying glasses can help.
Retinal detachment (detached retina):
Symptoms described: sudden curved loss of vision across the field, new floaters, flashes of light; may progress rapidly.
This is a true medical emergency requiring urgent ophthalmology evaluation; usually requires surgical or noninvasive procedures to reattach the retina.
Pain: detachment itself is often not painful because the retina tissues lack pain receptors; however, it is a concerning emergency because vision loss can be permanent if not treated promptly.
Safety and post-op parallels:
Postoperative care for retina-surgery follows similar patterns to cataract surgery with a structured drop regimen and activity restrictions.
Penetrating Eye Trauma
Scenario: foreign body or penetrating injury (e.g., glass) in the eye.
Immediate actions:
Do not touch or remove the object.
Stabilize the eye by covering with a protective rounded shield or cup, and avoid applying pressure.
Stabilize both eyes to prevent movement and further injury.
Seek urgent ophthalmologic care (often transfer to a trauma center or facility equipped for eye surgery).
Practical notes:
Do not attempt to remove the object; avoid anything touching the object.
Use a protective cover to prevent further damage during transport.
Chemical Exposure and Eye Irrigation
Chemical splash to the eye:
Immediate action: flush the eye with water or saline for approximately 15–20 minutes (time exact guidelines may vary by facility).
If available, use eye wash stations; otherwise flush with available sterile saline.
Goal: dilute and remove chemical irritants to minimize tissue damage.
Penetrating Trauma and Post-Op Follow-Up
Post-trauma care often involves eye surgery or noninvasive procedures depending on the injury.
Both acute trauma and post-op care share emphasis on safety, infection prevention, and protecting the eye during recovery.
Retinopathy, Stroke, and Perfusion Connections
Stroke-related visual symptoms:
Hemianopsia: loss of half of the visual field, often due to stroke.
Aphasia: difficulty speaking, can be affected by stroke; speech deficits may be global, expressive, or receptive.
Dysphagia: swallowing difficulties, can accompany stroke.
Note: stroke is a medical emergency; treatment targets perfusion and brain tissue, and vision changes may reflect underlying cerebrovascular events.
Implications for eye care:
Visual symptoms from stroke require urgent medical evaluation and coordination with neurological care; ophthalmology cannot fix stroke-related central vision loss.
When teaching patients with potential stroke, emphasize safety and acute management, as well as long-term adaptations for vision changes.
Safety, Accommodations, and Patient Education for Visually Impaired Individuals
Daily safety and orientation:
If vision is reduced, use a cane or guide technique; orient yourself to approach from a specific side (e.g., the left) to enhance safety.
Keep daily living items on one side to minimize disorientation.
Use proper lighting and high-contrast, large-font materials; provide instructions in accessible formats.
Reading and devices:
Encourage high-contrast displays and larger fonts; dark mode on devices can reduce eye strain for some with retinopathy or low vision.
Magnifying aids and appropriate assistive devices improve independence.
Preventive Measures and Real-World Relevance
Vision health maintenance:
UV protection (polarized sunglasses) to reduce ocular stress and phototoxic damage.
Diet and supplements: eye vitamins formulated for ocular health; a diet rich in fruits/vegetables and antioxidants supports overall eye health.
Real-world relevance:
Many conditions discussed (AMD, glaucoma, cataracts, diabetic retinopathy) are common with aging; early detection and management can preserve function and safety.
Patient education and home safety play central roles in maintaining independence and reducing injury risk.
Quick glossary of terms mentioned
Aphasia: difficulty speaking; can be global (entire language ability), expressive (trouble producing words), or receptive (trouble understanding).
Dysphagia: swallowing difficulties.
Hemianopsia: loss of half the visual field in one or both eyes.
Retinopathy: damage to the retina often due to diabetes; not immediately painful but can cause vision loss over time.
Macula: central part of the retina responsible for sharp central vision; AMD primarily affects the macula.
Intraocular lens (IOL): artificial lens implanted during cataract surgery.
Prostaglandin analogs and beta blockers: classes of eye drops used to reduce intraocular pressure in glaucoma.
Conjunctiva: the clear membrane lining the eyelids and covering the white of the eye where eye drops are applied.
Summary of key exam-ready points
AMD: central vision loss with preserved peripheral vision; not an acute emergency; treated with anti-VEGF eye injections when indicated; injections schedule: monthly → every 6 weeks → every 8 weeks → every 2–3 months; protect vision via lighting, contrast, and supplements.
Glaucoma: chronic open-angle (progressive, often asymptomatic) vs acute closed-angle (sudden, painful, vision loss). Treatment uses daily eye drops (beta blockers and prostaglandin analogs, often in combos) and urgent management for acute cases. Post-drop technique is essential to minimize systemic effects.
Cataracts: clouding of the lens causing halos and glare; not emergency; surgical removal with IOL replacement; strict pre/post-op instructions and a staged drop regimen.
Retinopathy and retinal detachment: diabetic retinopathy requires diabetes control; retinal detachment is an eye emergency requiring urgent ophthalmology intervention; pain is not always present in detachments.
Penetrating trauma and chemical exposure: do not touch the object; cover/protect; seek urgent care; flush chemical exposure for 15–20 minutes; eye wash stations when available.
Stroke-related vision changes: not an ophthalmic fix; urgent medical care needed; be aware of hemianopsia and aphasia; safety and rehabilitation considerations are critical.
Patient safety and accommodations: use brighter lighting, larger fonts, high contrast, and assistive devices; teach safe driving and home navigation; ensure proper protection during post-operative recovery.