Visual Sensory Disorders (Glaucoma, Cataracts, Corneal/Retinal Disorders, Retinal Vascular Disorders, Age-Related Macular Degeneration)

glaucoma

group of eye conditions characterized by increased IOP, leading to optic nerve damage & vision loss.

glaucoma

”silent thief of sight”

canal of Schlemm

what is blocked in glaucoma?

mechanical theory

Glaucoma Theory: High IOP directly damages the retinal layer.

ischemic theory

Glaucoma Theory: High IOP compresses optic nerve blood flow.

Primary Open-Angle Glaucoma

type: gradual blockage of drainage channels

Primary Open-Angle Glaucoma

Sx: gradual vision loss, no pain

Angle-Closure (Narrow-Angle) Glaucoma

sudden closure of drainage angle

Angle-Closure (Narrow-Angle) Glaucoma

Sx: severe eye pain, nausea, halos, blurred vision (medical emergency)

Congenital Glaucoma

Sx: enlarged eyes, excessive tearing, light sensitivity

glaucoma

Sx: tunnel vision, blurred vision, halos around lights

eye pain, headache

Acute symptoms of glaucoma

scotoma

a partial or total blind spot in your vision

beta-blockers (-olol)

first choice meds for glaucoma?

Laser trabeculoplasty; glaucoma

opens drainage channels; surgery for what disorder?

Trabeculectomy; glaucoma

creates a new drainage pathway; surgery for what disorder?

cataracts

clouding of the eye lens, causing blurred vision.

cataracts

leading cause of blindness worldwide

cataracts

Sx: increased sensitivity to glare & light scattering; reduced contrast sensitivity; monocular diplopia

Phacoemulsification; cataracts

removes cataracts and replaces the eye's lens with an artificial lens; surgery for what disorder?

aphakic glasses

rare; distorts images, limits peripheral vision

contact lenses

good vision, but requires handling & care

IOL implant

most common & effective; provides nearly normal vision

Assess for use of alpha-antagonists like tamsulosin which can cause floppy iris syndrome

most important pre-op care for cataracts?

retinal detachment, infection

Complications of cataracts surgery?

6-12 weeks

how long will full healing & visual stabilization take after cataracts surgery?

Corneal dystrophies

genetic, appear around age 20; deposits form in the cornea, leading to irregular surface, blurred vision and corneal edema.

Keratoconus

cornea thins & bulges into a cone shape, leading to irregular astigmatism.

rigid gas-permeable contact lenses (correct vision); corneal transplant (severe cases)

management for cone-shape bulging cornea?

Fuchs Endothelial Dystrophy

slow loss of endothelial cells, leading to edema & bullous keratopathy

hypertonic drops & bandage contact lenses (reduce edema); corneal transplant is the only cure

management for bullous keratopathy?

Phototherapeutic Keratectomy (PTK); corneal disorder

laser removes diseased corneal tissue, improves vision; surgery for what disorder?

Penetrating Keratoplasty (PKP); corneal disorder

corneal transplant; surgery for what disorder?

Descemet’s Stripping Endothelial Keratoplasty; corneal disorder

partial corneal transplant; surgery for what disorder?

Keratoprosthesis; corneal disorder

artificial cornea for patients with multiple failed grafts; surgery for what disorder?

Photorefractive Keratectomy (PRK); refractive disorder

laser reshapes cornea; surgery for what disorder?

LASIK; refractive disorder

creates a corneal flap, reshapes the underlying cornea; surgery for what disorder?

Phakic Intraocular Lenses (IOLs); refractive disorder

implanted lenses for moderate to severe myopia; surgery for what disorder?

Conductive Keratoplasty (CK); refractive disorder

uses radiofrequency to reshape the cornea for mild hyperopia; surgery for what disorder?

irregular astigmatism and central islands

potential complications for corneal/refractive surgeries

Retinal Detachment

separation of the retinal pigment epithelium from the sensory retina.

Rhegmatogenous

caused by a hole or tear in the retina, allowing fluid to enter and separate layers.

Rhegmatogenous

most common type of retinal detachment

Tractional

caused by fibrous bands pulling on the retina.

Exudative

caused by fluid buildup under the retina.

retinal detachment

Sx: Curtain vision, photopsia, floating spots, no pain

Scleral Buckling; retinal detachment

silicone band wrapped around eye to push detached retina back into place; surgery for what disorder?

Vitrectomy; retinal detachment

removes vitreous gel to access and repair a detached retina; surgery for what disorder?

if gas bubble is used, patient must remain prone to keep pressure on retina

nursing alert post-surgery in retinal detachment?

Retinal vascular disorders

occur due to blocked arteries or veins in the retina, leading to vision loss.

Central Retinal Vein Occlusion (CRVO)

blocked central retinal vein leads to blood congestion in the retina.

Central Retinal Vein Occlusion (CRVO)

Sx: blurry vision, retina appears “bloody” with swollen optic disc & cotton-wool spots

Monitor for worsening symptoms; Laser panretinal photocoagulation (prevents neovascularization)

treatment for CRVO?

Branch Retinal Vein Occlusion (BRVO)

blockage of a smaller branch of the retinal vein.

Branch Retinal Vein Occlusion (BRVO)

Sx: retinal hemorrhages & dilated veins

Central Retinal Artery Occlusion (CRAO)

true ocular emergency; sudden vision loss due to blocked central retinal artery.

Central Retinal Artery Occlusion (CRAO)

Sx: pale retina with a cherry-red spot at the fovea

1. Ocular massage: to dislodge clot

2. Anterior chamber paracentesis: reduces eye pressure

3. Hyperbaric oxygen therapy

4. IV mannitol & acetazolamide: to lower IOP

5. Anticoagulants

5 tx for CRAO?

age-related macular degeneration

Leading cause of irreversible blindness worldwide.

age-related macular degeneration

Affects central vision but preserves peripheral vision.

Dry (Non-Neovascular, Non-Exudative) AMD

slow, gradual breakdown of the retina. Drusen deposits accumulate, leading to blurry central vision. NO CURE, but progression may be slowed.

Wet (Neovascular, Exudative) AMD

Choroidal neovascularization, then these vessels leak fluid & blood, causing rapid vision loss.

Wet (Neovascular, Exudative) AMD

Sx: Straight lines appear wavy or distorted. Letters in words appear broken

VEGF Inhibitor (-zumab); laser therapy may stop leakage from abnormal blood vessels

Management for wet AMD?

Amsler Grid Monitoring; diet rich in leafy greens, fish, and antioxidants to slow progression

Nursing mt and diet for loss of central vision?