Sensory- Eye disorders

What are refractive errors?

a change in light’s focal point

What happens in normal vision?

light hits the back of the retina

What is hyperopia?

far sightedness, light is concentrated way way beyond the retina 

What is myopia?

light is focused IN FRONT of the retina- near sightedness 

What is astigmatism?

light hits in all different places

what happens when someone has a cataract?

Lens clouds, so everything dims together 

how do cataracts present?

• Painless, gradual, whole field blur 

• Glare and halos; night driving gets hard 

• Colors faded or yellowed 

• Frequent prescription changes 

• Cloud lens, dimmed red reflex on exam 

What is the main risk factor for cataracts?

aging

What are risk factors for cataracts? (think light exposure, medications)

• Aging is dominant 

• Ultraviolet exposure 

• Smoking 

• Diabetes 

• Long-term corticosteroids 

• Ocular trauma or prior eye surgery 

How do we diagnose cataracts?

• Visual acuity 

• Sit-lamp exam 

• Ophthalmoscopy for the red reflex 

• Biometry to size the implant before surgery 

What’s the ultimate cure for cataracts?

replacing the lens in the eye

What are the steps of lens removal and repair for cataracts?

1. outpatient, topical anasthesia

2. phacoemulsification

3. intraocular lens implanted

how does sedation work in cataract surgery? do you do both eyes at once?

Awake and sedated, home in hours, one eye at a time, never both 

What is phacoemulsification?

Ultrasound breaks the clouded lens apart, fragments are aspirated through a tiny incision 

how does the lens being implanted work?

Synthetic lens sits in the capsule. Nothing has to be held in position afterward 

What would you anticipate orders for after cataract surgery?

• Antibiotic and corticosteroid drops on a taper 

• Eye shield at night 

• Follow-up next day 

• Second eye scheduled separately 

what should the patient not do after cataract surgery?

• Don't rub or press eye 

• Avoid coughing, sneezing, lifting bending 

• Sunglasses for glare 

• Assess dexterity- arthritis or tremors mean someone else instills

What should a patient report after cataract surgery?

• pain (discomfort is normal)

• vision worsens or suddenly drops

• purulent drainage or spreading redness

• new flashes, floaters or a shadow

how does vision change after cataract surgery? whats the timeline?

vision improves over days

What’s normal after cataract surgery?

mild scratchiness and light sensitivity- flashers and floaters gradually decrease

What’s a known complication of cataract surgery?

dettachment

What happens in macular degeneration?

the center goes, the edges stay

what percentage of macular degeneration is dry and what percentage is wet?

dry- 85%

wet- 15%

what happens in dry macular degeneration?

drusen accumulates, retinal cells atrophy

whats the timeline of dry macular degenration

its slow, over years

What happens in wet macular degenration?

Vessels leak under macula 

Whats the timeline in wet macular degeneration?

sudden distortion, rapid loss

What is the largest risk factor for macular degeneration?

age over 50

What is the strongest modifiable risk factor for macular degeneration?

smoking

What are risk factors for macular degeneration?

• age over 50

• smoking

• family history

• hypertension, cardiovascular disease

• lighter iris pigmentation (blue over brown)

how does macular degeneration present- what leads up to it?

• Cannot read or recognize faces 

• Straight lines look wavy or bent 

• Blank patch wherever they look 

• Amsler grid, dilated fundoscopy, OCT 

• Fluorescein angiography if leakage suspected 

Can you solve macular degeneration through surgery?

no surgery for macular degeneration

what orders would you anticipate for macular degeneration?

• AREDS2- formula supplementation for intermediate or advanced dry AMD Intravitreal anti-VEGF injections on a repeating schedule for wet AMD 

• photodynamic or laser therapy in certain cases

• low-vision rehabiliation referral

what could the nurse teach the patient to do for macular degeneration?

• Amsler grid daily, one eye at a time, wearing reading glasses 

• Smoking cessation- highest-yield instruction you have 

• Magnifiers, large print, high contrast, strong task lighting 

• Label medication by touch or color; verbal identification, not written signange 

• Keep every injection appt. The schedule is the treatment 

what should a patient report after macular degeneration surgery?

• New or worsening distortion- same day, not next visit 

• A new or enlarging blank patch at center 

• Pain- worsening redness, or vision loss after an injection 

• Any sudden change in one eye 

what changes can you make in care for macular degeneration patients?

build teaching around hearing things, not seeing it- they can navigate rooms but they may struggle to read medication lables

What is diabetic retinopathy?

Hyperglycemia damages retinal blood vessels 

What is the mechanism behind diabetic retinopathy?

1. Chronic hyperglycemia weakens retinal capillaries- they leak then occlude 

2. No proliferative: microaneurysms, dot blot hemorrhages, hard exudates, macular edema 

3. Ischemic retina releases VEGF, driving fragile new vessels- proliferative disease 

4. Those vessels bleed into the vitreous and pull the retina off 

What is the strongest predictor of diabetic retinopathy?

duration of diabetes

whats the second risk factor of diabetic retinopathy?

glycemic control

what are other risk factors of diabetic retinopathy?

Hypertension, hyperlipidemia, nephropathy, smoking pregnancy 

Why is diabetic retinopathy bad?

its silent until its advanced- the leading cause of blindness in working age adults

What’s used to detect diabeetic retinopathy?

Dilated exam,

optical coherence tomography for edema,

fluorescein angiography 

what orders would you anticipate for a patient with diabetic retinopathy?

• Glycemic, blood pressure and lipid control 

• Intravitreal anti-VEGF for macular edema and proliferative disease 

• Focal or grid laser, pan retinal photocoagulation 

• Vitrectomy for vitreous hemorrhage or tractional detachment 

What would you teach the patient about diabetes retinopathy?

• Dilated exam every year even when vision is normal 

• Type 2: at diagnosis, Type 1: within five years then annually 

• Pregnancy needs closer monitoring 

• Warn before pan retinal laser: it trades peripheral and night vision to save central vision

What would you teach a patient to report in regard to diabetes retinopathy?

• Sudden floaters or a red haze- vitreous hemorrhage 

• A curtain or shadow- tractional detachment 

• New blurring or distoriton of ventral vision 

• Any sudden change in one eye 

What is glaucoma?

Production never stops so drainage sets pressure 

how does glaucoma happen?

1. Ciliary body makes aqueous (contintously, day and night) 

2. Drainage is impeded (at the trabecular meshwork) 

3. Intraocular pressure rises (globe cannot expand)  

4. Optic nerve axons die (peripheral fibers first) 

Why is the loss of optic nerve axons permanent?

Dead axons do not regrow, treatment protects the field that reamins, it never restores what is gone 

What are some risk factors for glaucoma?

• Age over 40 

• Family history 

• African ancestry 

• Diabetes 

• Hypertension 

• Myopia 

• Long term corticosteroids 

• Thin cornea 

How is glaucoma diagnosed?

tonometry for pressure,

disc assessment for cupping,

perimetry for the field,

gonioscopy for the angle 

What is the timeline on primary open angle glaucoma?

slow and silent

how does the meshwork drain in primary open angle glaucoma?

• Angle open, meshwork drains sluggishly 

• No symptoms for years 

What happens to vision in primary open angle glaucoma?

• Painless peripheral loss; tunnel vision late 

• Pupil normal, cornea clear 

• cupped disc, pressure often elevated

how is primary open angle glaucoma found?

its found on routine screening?

whats the timeline in acute angle closure glaucoma?

its sudden and emergent

what happens to the iris in acute angle closure glaucoma?

iris is pushed forward, angle is physically sealed

What symptoms happen in acute angle closure glaucoma?

• Sudden severe eye pain and headache 

• Halos, blurred vision, red eye 

• Fixed mid-dilated pupil, hazy cornea, hard globe 

• Nause and vomiting- often misread as GI 

• Triggered by dilation: dim light, mydriatics, anticholinergics 

What is acute angle closure glaucoma triggered by?

dilation, dim light mydriatics, anticholinergics

how do you manage glaucoma?

need to lower the pressure and restore outflow

what orders would you anticipate to treat chronic open angle glaucoma?

Lifelong pressure-lowering drops: prostaglandin analogs, beta blockers, alpha agnositcs, topical carbonic anhydrase inhibitors 

how do lifelong pressure-lowering drops (prostaglandin analogs, beta blockers, alpha agnostics, topical carbonic anhydrase inhibitors) work?

decreasing aqueous production or by increasing outflow (or both) 

whats another treatment for chronic open angle glaucoma when drops arent enough

• Laser trabeculoplasty when drops are not enough 

• Trabeculectomy or a drainage shunt for uncontrolled pressure 

what orders do you anticipate for acute closure glaucoma?

Emergency pressure reduction with combined topical agents plus systemic acetazolamide or an osmotic agent 

miotic once pressure falls

defintive laser peripheral iridotomy- usually in the other eye too

What does trabeculoplasty do for glaucoma?

helps the existing meshwork drain

What is an iridotomy

an opening in the iris bypasses a sealed angle

What does trabeculectomy do?

builds a new outflow channel under the conjunctiva

what do none of the treatments for glaucoma do?

• No procedure restores lost vision, and patients still need their drops afterward 

• Iridotomy treats the anatomy, not the episode—which is why the other eye gets treated too, since the same shallow angle is there 

how long do you have to do drops for glaucoma?

continue for life even after laser or surgery 

what should the patient not be after filtering surgery doing?

Shield and activity limits after filtering surgery- no lifting, bending, straining 

what are the steps for giving eye drops?

1. Wash hands, tilt head back, pull down the lower lid to form a pouch

2. one drop in pouch, tip should touch nothing

3. close gently, press inner corner one full minute (punctual occlusion)

4. five minutes between different drops

5. never ski or stop because the eye feels fine

6. prostaglandins darken the iris and lengthen lashes- say so first

what should you teach a patient to report after glaucoma treatment?

• New wheezing or shortness of breath 

• A pulse that feels slow, dizziness, fainting 

• Eye pain or vision change after a procedure 

• Running out of drops before the refill 

What happens in retinal detachment?

• Photoreceptors separate from their blood supply 

• Shade coming down over one eye- doesn't hurt 

What are risk factors for retinal detachment?

• High myopia 

• Prior cataract surgery 

• Aging vitreous 

• Blunt or penetrating trauma 

• Previous detachment, either eye 

• Diabetic retinopathy 

how does retinal detachment present?

• Shower of new floaters 

• Flashes of light in the periphery 

• A curtain or shadow across the field 

• Acuity drops sharply if the macula lifts 

• Dilated indirect ophthalmoscopy ultrasound if the view is blocked 

why is retinal detachment time critical?

Detached retina is cut off from the choroidal supply beneath it. Photoreceptors stop signaling with hours, and once the macular lifts, central vision may not fully return even after successful surgery 

How do you fix retinal detachment?

seal the break, hold the retina down

what are ways to treat retinal detachment?

• laser cryopexy

• pneumatic retinopexy

• scleral buckle

• vitrectomy

what doers laser cryopexy do?

scars the edges of a tear so fluid cannot track underneath. For tears found before detachment 

What does pneumatic retinopexy do?

A gas bubble is injected to press the retina back, positioning aims the bubble at the break 

What does a scleral buckle do?

A silicone band indents the wall of the eye inward to meet the detached retina 

What does vitrectomy do?

Vitreous is removed and replaced with gas or oil to tamponade the retina from the inside 

What orders should you anticipate for the treatment of retinal detachment?

• Same-day ophthalmology evaluation and surgical repair 

• A specific positioning order after gas tamponade 

• Antibiotic and corticosteroid drops 

What is an important fact about the gas bubble treatment?

If a gas bubble was placed, the bubble is the treatment. It only presses where it floats, and because it is a gas, it expands when outside pressure drops  

what would you anticipate for after retinal detachment repair?

• Face down or a specific head tilt, exactly as the surgeon specifies 

• Most of every hour, day and night, for days to weeks 

• No lifting or straining 

• Drops as ordered 

What can patients not do while the gas bubble is present in their eye?

• No air travel and no high-altitude driving 

• No nitrous oxide—tell every anesthesia provider 

• Medical alert identification until it absorbs 

• Only the surgeon says when the bubble is gone 

• Plan support at home: positioning wrecks sleep, meals and toileting  

What should you teach a patient to report after retinal detachment repair?

• Increasing pain or a hard, red eye 

• Vision worsening rather than slowly improving 

• New flashes, floaters or a returning shadow 

• Drainage or signs of infection 

how does vision return after retinal detachment repair?

Vision returns over weeks to months, not days, and may not return fully if the macula lifted. Positioning is key, even at night when sleeping. 

what is the visual acuity (snellen) test?

Reads a letter chart at 20 feet, one eye at a time 

What does the visual acuity (snellen) test tell you?

Central vision; baseline for every eye complaint 

What is the slit-lamp exam?

Magnified light-beam view of the front of the eye 

what does the slit lamp exam tell you?

Cornea, anterior chamber, lens clarity — grades cataract 

What is the ophthalmoscopy, dilated?

Direct view of the retina and optic disc 

what does ophthalmoscopy tell you?

Drusen, detachment, disc cupping, diabetic changes 

What does tonometry do?

Measures intraocular pressure 

What does tonometry tell you?

Screens and monitors glaucoma; very high in angle-closure 

What is gonioscopy?

Mirrored lens views the drainage angle 

what does gonioscopy tell us?

Separates open-angle from angle-closure 

what does perimetry (visual fields) do?

Maps where the patient detects light 

what does perimetry tell us?

Peripheral loss in glaucoma; central scotoma in AMD