Outcome 3 - Recognize Ocular Pathologies - Concept one: Internal layer Flashcards
Retinal Detachment (RD)
Separation of inner neurosensory retina and outer retinal pigment epithelum (RPE)
- Space between fills w/ sub-retinal fluid
RPE
Retinal Pigment Epithelum
RD
Retinal Detachment
Most Common Detachment
Rhegrmatogenous Detachment
- caused by tear/hole in retina
What happens if retina tears?
Vitreous seeps thru opening
- Fluid accumulates underneath retina, retina peels away from back of eye
What is vitreous?
- Gel-liked fluid that fills the eye
- Full of tiny fibers that attach to the retina
Risk factors of Retinal Detachment
- Aging
- Having cataract surgery
- Thinning of outer retina (lattice degeneration)
- High myopia
- Head trauma
Macula-on detachment
- Macula had not detached yet
- Still attached to underlying RPE
Macula-off detachment
- Detached from RPE
- Macula peeled away from underlying RPE
Symptoms of Retinal Detachment
- Most common: shadow spreading across vision on one eye, blank spot, curtain or cob-web vision
- Light flashes
- Floaters
Retinal Detachment seen w/ opthalmoscope
- Detached area: gray/brownish green
- Can have horseshoe-shaped tear in affected eyes
What is lattice degeneration?
Occurs when areas in peripheral atrophy or deteriorate in lattice pattern
What is atrophy?
Waste away, especially as result of degeneration of cells
Lattice Degeneration is common in…
Moderate to high myopia
What is Central Retinal Pathology?
Cone cells located in macula regions allow most detail central vision used in:
- Reading
- Sewing
- Observing facial features
What is degenerative myopia?
More severe than other forms of myopia - changes within central retina
*potential in severe vision lost
Progressive elongation of the eye happens with…
Degenerative myopia
- Thinning of choroid and retina’s pigment epithelum of the macula
What happens to the retinal tissue in degenerative myopia?
The retinal tissue develops cracks cause by breaks in Bruch’s membrane
Degenerative myopia commonly occurs in…
Young adulthood and people with higher myopia (they’re are greater risk)
Causes of degenerative myopia?
- Biochemical abnormalities
2. Hereditary factors
RP
Retinitis Pigmentosa
Retinitis Pigmentosa
Group of diseases that affect the retina - causes degeneration of tissue and diminishes vision
Is Retinitis Pigmentosa hereditary? And what happens?
Yes.
- Causes cell death of rod and cones and the eventual atrophy of several retinal layers
Symptoms of Retinitis Pigmentosa?
- Night blindness
- Tunnel vision
- Increases overtime, peripheral diminishes and only a small central area of vision remains
People are considered legally blind when they have…
Retinitis Pigmentosa
What is Central Serous Retinopathy (CSR)?
Swelling that reduces or distorts vision
- caused by a small, round, shallow swelling of the retina
What is edema?
Swelling/Inflammation
Initial stages of Central Serous Retinopathy?
- Vision suddenly becomes blurred/dim
Are reoccurrences common in Central Serous Retinopathy?
Yes, can affect 20-50% of people.
When does Central Serous Retinopathy tend to occur?
- Personal/Work-related stress
- People who have “type A” personality
- Prolonged use steroid medication
If Central Serous Retinopathy frequently occurs, what happens?
Possible permanent vision loss
What is a Macular hole?
When multiple layers of the central retina are destroyed
- caused by vitreous body pulling away from tissues surrounding macula area
Who commonly gets macular holes?
The elderly, typically is it unilateral
Macular hole central vision changes in early stages show:
Straight lines look wavy on Amsler grid
Macular hole central vision changes in late stages show:
Small blank patches on Amsler grid
What is the leading cause of irreversible vision loss in western world?
Age related macular degeneration (ARMD)
ARMD
Age related macular degeneration
TWO FORMS OF ARMD ARE:
- Exudative aka Neovascular aka WET ARMD
2. Nonexudative ARMD aka DRY ARMD
Most is the most severe ARMD?
Wet
When is DRY ARMD diagnosed?
When drusen begins to accumulate in/around macula
Early stages of DRY ARMD result in?
- Aging
- Thinning of macular tissues and/or deposits of pigment in the macula
Symptoms of DRY ARMD?
- Gradual vision loss (not as severe as WET ARMD)
- progress to late stage of geographic atrophy > gradual deterioration of retinal cells > severe vision loss
What is WET ARMD?
New blood vessels grow beneath the retina and leak blood and fluid.
Leakage causes permanent damage to light-sensitive retinal cells which cause them to die off and create blind spots in central vision
What is Choroidial neovascularization (CNV)?
The underlying process of causing WET ARMD
Wet macular degeneration falls into two categories:
- Occult
2. Classic
What is OCCULT in WET ARMD?
- Occurs w/ new blood vessel growth behind the retina
- Vessels not as pronounced and leakage is less evident
!! produces less critical vision loss
What is CLASSIC in WET ARMD?
- Blood vessel growth and scarring have very clear outlines that can be observed beneath the retina
- referred to classical choroidial neovascularization (cnv)
!! produces MORE damage = vision loss
Symptoms of WET ARMD?
- difficulty reading w/o extra light and magnification
- blindspot in center vision
- inability to see detailed features
- distorted or blurring of objects in colour, size or shape
- difficulty seeing to read or drive
Stages of ARMD are defined by?
The size and number of drusen under the retina
Early ARMD
- diagnosed by presence of medium drusen (width of human hair)
- people with early ARMD don’t experience vision loss
Intermediate ARMD
- typically large drusen
- pigment changes in retina
- only detected in eye exam
- may cause vision loss
Late ARMD
- in addition to drusen, people have vision loss from damage to the macula
Two types of late ARMD:
- Geographical atrophy in DRY ARMD
2. Neovascular ARMD
What is Geographical DRY ARMD?
- A type of late stage of ARMD
- caused by gradual breakdown of the light sensitive cells in the macula that convey visual images to brain
- interruption of supporting tissue beneath macula
What is Neovascular WET ARMD?
- type of late stage of ARMD
- abnormal blood vessels grow underneath retina
- can leak fluid and blood = swelling and damage to the macula
Is it possible to have geographic atrophy and neovascular ARMD in the same eye?
Yes, either condition can appear first
Everyone with early ARMD will develop late ARMD, true or false?
False. approx. 5% of patients who have early ARMD and no signs of ARMD in the other eye will develop advanced ARMD within the next ten years
14% who have early ARMD in both eyes will develop late
ARMD in at least one eye after approx. 10 years
Risk factors of ARMD?
- Age *major risk factor
- Smoking *doubles risk
- Family history *high risk
- Race *common in Caucasians
- Unprotected exposure to UV
Does macular degeneration produce pain?
No, neither type does.
Does macular degeneration result in complete blindness?
No, almost never results in total blindness. People have enough peripheral vision to get around and be somewhat independent.
How do you detect ARMD?
- Use an Amsler grid
- Eye exam
What is Vascular Retinal Disease?
Systems in the body having to do with blood vessels and blood supply
What is Diabetic Retinopathy?
Has a few visual or opthalmic symptoms until serious vision loss develops
What should a diabetes patient do?
- Treated early in diagnosis
- Annual dilations
- Early diagnosis
Types of diabetes?
Type 1 - body producing not enough insulin
Type 2 - body does produce some insulin but not a sufficient amount to use
Type one diabetes is common in?
- Children, teenagers or adults under 30
- People who have latent autoimmune diabetes in adults (LADA) *immune response related to loss of pancreatic cells
How is type one diabetes controlled?
Primarily controlled by insulin injections
Type 1s are referred to as…
Insulin Dependant Diabetes
Type two diabetes in controlled by….
combination of diet, exercise and/or medication
Ocular complications of diabetes?
- cataracts
- glaucoma
- diabetic retinopathy
What is Branch Retinal Vein Occlusion (BRVO)?
Painless, decrease in vision.
*Hazy/distorted vision
If veins that cover larger area are blocked, what happens? (BRVO)
New abnormal vessels may grown on the retinal surface which results in *hemorrhaging into the vitreous
BRVO
Branch Retinal Vein Occlusion
What is Central Retinal Vein Occlusion? (CRVO)
- Common vascular disorder within retina w/ potentially blinding complications.
- patient will have painless, sudden vision loss!!
- similar to BRVO
What causes CRVO?
- Central vein is blocked, the central vein usually drains out blood from retina. If blood flow is interrupted, it leaks into the retina. = edema in macular region
What causes BRVO?
Small retinal veins are blocked and if the veins that nourish the macula are blocked, it causes some central vision loss.
What is Central Retinal Artery Occlusion (CRAO)?
Centra artery is blocked
CRVO
Central Retinal Vascular Occlusion
CRAO
Central Retinal Artery Occlusion
Common cause of CRAO?
- Abnormal blood clot (thrombosis)
- Also can be caused by embolus (a clot that breaks off from another area of the body and is carried to the retina by blood stream)
First signs of CRAO?
- sudden and painless vision loss
* barely can count fingers or determine light and dark
What is common associated with Arteriosclerosis?
CRAO
What is Arteriosclerosis?
Carotid disease found in almost half of patients with CRAO
Risk factors of BRVO and CRAO?
- hypertension
- diabetes
- carotid artery disease
- coronary artery disease
- transient ischemic attacks (TIAs)
- cerebral vascular accidents (Strokes)
