eye diseases patho

anatomy of eyes

•Sclera
•Cornea
•Choroid
•Ciliary body
•Iris
•Pupil
•Retina, which contains rods and cones
•Optic nerve

Aqueous humor

watery liquid in anterior chamber

Vitreous humor

clear, gelatinous material in posterior chamber

Conjunctiva:

fragile membrane that covers the inner surface of the eyelid and the exposed surface of the eye

Lacrimal glands

keep surface moist
Tears drain on the inner side through two lacrimal ducts

Blinking

•cleans the eye by sweeping the fluid

Sensory Conditions Associated with Aging: Eyes

•Changes:
•Less tear production
•Structural deteriorations
•Cornea becomes less sensitive
•Pupils decrease in size/react more slowly
•Lens becomes yellowed, less flexible, slightly cloudy
•Fat pads decrease
•Eye muscles weaken
•Presbyopia
•Intolerance to glare/difficulty adapting to darkness
•Inability to distinguish color

aging eyes treatment

•Glasses/contact lenses
•Keeping a red light on in darkened rooms

Refraction

•Controls clarity of vision regardless of distance
•Refraction errors affect 1/3 of persons aged 40+ years
•Advanced age increases risk for all 4 refractive disorders

•4 refractive errors

•Occur when bending of light rays by the cornea and lens does not focus image correctly on the retina
•Myopia, Hyperopia, Astigmatism, Presbyopia

•Myopia (Nearsightedness)

•Corrective lenses such as glasses or contact lenses

•Hyperopia (Farsightedness)

•Convex corrective lenses in eyeglasses or contact lenses

Astigmatism

a condition in which the eye does not focus properly because of uneven curvatures of the cornea •Eyeglasses, contact lenses, or orthokeratology

•Presbyopia

•"Reading glasses" or magnification

Corneal Abrasion

•Epidemiology
•Contact lens wearers present more frequently
•2 types of abrasions
•Superficial
•Deep

Pathophysiology Corneal Abrasion

•Disruption of the cornea resulting from a physical or chemical trauma

Corneal Abrasion •Clinical manifestations

•Traumatic corneal abrasion
•Foreign bodies
•Contact lenses
•Spontaneous defects

Corneal Abrasion •Management includes comprehensive exam

•Visual acuity test, anesthetizing eye, corneal staining, and visualization under a Wood lamp/black light

Cataracts

•Opacity of clouding of the lens of the eye

Cataracts epidemiology

•Affect 22 million Americans aged 40+ years
Most reimbursed Medicare Procedure

Cataracts Risk Factors

•Exposure to UV light
•Advanced age
•Family history
• DM, HTN
•Obesity
• Smoking, alcohol abuse, and many other chronic diseases

Cataracts •Pathophysiology

•Affects the lens which is made up of water and protein in a unique pattern to keep the lens clear.
•Alteration in the lens proteins occurs as a person ages; protein clumps together and makes the lens unclear
•Gradual lens clouding secondary to chemical change
•Can also be do to blunt trauma

Cataracts Clinical Manifestations

•Opaqueness
•Affects central vision (What you see straight ahead)
•Decreased visual acuity
•Blurred or distorted vision
•Unable to distinguish colors
•Progresses to diplopia, absent red reflex, white pupil, and can lead to blindness
•Halos around lights
•No pain or eye redness

cataracts diagnosis

•History
•Exam

cataracts treatment

•Surgery (removal of the cataract or a lens transplant)
•Managing/eliminating contributing factors

Glaucoma

•Group of eye conditions that lead to damage to the optic nerve
•Results in decreased blood flow to the optic nerve
•Open-angle
•Angle-closure

Glaucoma Epidemiology

•Anyone can develop glaucoma
•2.2 million Americans have been diagnosed
•Another 2 million people have the disease without knowing

Glaucoma Pathophysiology

•IOP increases due to pressure changes in the aqueous Chamber
•Increased pressure leads to ischemia, lack of oxygen and cell death
•Damage to the optic nerve occurs and results in vision loss beginning with peripheral vision

Glaucoma risk factors

•Family Hx
•African American decent
•Trauma

Glaucoma Diagnosis

•History
•Exam

•Primary open Angle Glaucoma

•Gradual loss of vision in both eyes
•Headaches, mild eye pain, decreased accommodation, halos around lights
•IOP > 21 mm Hg

•Acute angle glaucoma

•Eye pain
•Sudden onset
•Emergency

glaucoma treatment

• focuses on decreasing intraocular pressure and varies based on type
•Best prevention is regular eye exams
•Medications
•Laser surgery
•Drainage Implants

Macular Degeneration Epidemiology

•Most common age-related disease
•Gradually destroys sharp, central vision

Macular Degeneration Risk Factors

•Family history
•Female
•Caucasian decent
•Smoking,
•Increased UV light exposure (natural or artificial)
•High-fat diet,
•Decreased carotenoid intake
•Cardiovascular disease, hypertension, high cholesterol
•Obesity

Macular Degeneration Pathophysiology Dry

•Dry macular degeneration
•Dry form can turn into wet macular degeneration
•3 Phases
•Early
•Intermediate
•Advanced

Macular Degeneration Pathophysiology Wet

•Wet macular degeneration ( Develops after having dry)
•Damage to the macula occurs rapidly

Macular Degeneration Clinical Manifestations Dry

•Dry macular degeneration:
•Gradual blurring of central vision
•Difficulty recognizing faces
•Difficulty seeing in low light

Macular Degeneration Clinical Manifestations Wet

•Wet macular degeneration
•Distortion of straight lines
•Quick loss of central vision
•Dark spot in central vision
•Known as advanced macular degeneration

Macular Degeneration Diagnosis

•History
Exam

Macular Degeneration treatment Dry

none, but Age-Related Eye Disease Study 2 formula may slow progression

Macular Degeneration treatment Wet

•Wet: laser surgery, photodynamic therapy, antiangiogenics /antivascular endothelial growth factor therapy