BIO II Flashcards
There is more scalloping on the ora serrata. Nasal or temporal?
Nasal has more scalloping.
Temporal is smooth
What landmarks can you use to determine where the equator is?
Vortex veins. People usually have 4 in all diagonals. Can have up to 15, so don’t be alarmed.
Macula is usually how many DD?
What about the fovea?
Macula: 4
Fovea: 1
The equator divides which two poles
Anterior and posterior poles. It is the imaginary circle through ampullae of vortex veins.
Where do superior vortex veins drain?
What about inferior?
Superior drain into superior ophthalmic vein
Inferior drain into inferior ophthalmic vein
Ora Serrata is junction between
Neural retina and ciliary body. It is the anterior most portion of the retina.
2mm wide nasal, 1mm wide temporal
How wide is ora serrata nasal and temporal in mm
2mm nasal, 1mm temporal
Procedure used to view ora serrata
Scleral indentation.
Pars plana of the ciliary body
Broad, flat, pigmented chocolate colored band from pars ciliaris (tips of ciliary process) to ora serrata.
What is the pars plana composed of? Is it pigmented or non pigmented, and what layers does it have?
Inner non pigmented epithelium. Outer pigmented epithelium.
Basal lamina, and layer of blood vessels.
Pars plana. How wide nasally and temporally. in mm
4mm nasal, 5mm temporal
Corona ciliaris (ciliary crown)
- How wide
- How many ciliary processes
- layers
Anterior portion of ciliary body.
2mm wide
Contains 60-70 ciliary process.
Composed of non-pigmented and pigmented epithelium, stroma, blood vessels, and smooth muscle.
Location of long ciliary nerves
3 and 9 oclock
Location of short posterior ciliary nerves
6 and 12 oclock. Can have 10-20 nerves located all around the eye other than at 3 and 9 o clock (long ciliary nerves are there)
Choroidal pigment will surround which nerves?
Short posterior ciliary nerves
Long posterior ciliary nerves divide the retina horizontally into which hemispheres
Superior and inferior. They run from midperiphery to ora strata.
Long posterior ciliary nerves are usually accompanied by
Long posterior ciliary arteries
The vitreous body fills how much of the globe
2/3rd
What is the vitreous body composed of?
- Mostly collagen type 2 (60-75%) Unbranched, elastic, bouncy.
- hyalocytes that produce glycosaminoglycans/hyaluronic acid.
- 98% water
- Other collagen types include type 5, 9 and 11.
Vitreous cortex. What is it and what are the two areas?
Shell of condensed vitreous that surrounds gel.
- Anterior hyaloid face starts anterior to ora serrata.
- Posterior hyaloid face adheres to ILM of retina. Very very thin.
Firmest attachments of the vitreous cortex from most to least
Firmest Vitreous base straddles ora serrata Optic disk Macula Retinal blood vessels Weakest
Another word for vitreous base
Vitreoretinal symphysis
Can a PVD occur at the vitreous base?
NO
Vitreous base margins (3)
Anterior margin- white ridge on pars plana
Vitreous base is hyper pigmented in the middle
Posterior border is invisible.
When drawing retinal finings, draw 3 concentric circles that represent
Pars plana, ora serrata, equator. Mark fovea with an X
What does CHRPE stand for
Congenital hypertrophy of the RPE
Presentations of CHRPE
Bear tracks, solitary pigmented lesion with or without hypo pigmented halo. Looks scary, but not.
What causes CHRPE
Due to RPE hyperplasia or hypertrophy.
Another name for nevus
Benign choroidal melanoma
What is nevus caused by
Hyperpigmentation of choroid. Accummulation of normal melanocytes in choroid.
How does nevus appear
Flate, sate gray lesion with indistinct margins.
When might a nevus convergence to malignancy
Onset of pregnancy may cause growth or conversion to malignancies.
What kind of retinal detachment may occur near nevus
Isolated serous sensory retinal detachment.
White without pressure appears as what.
Area of translucent white to gray retina between equator and ora serrata. More frequently seen in AA.
What causes White without pressure?
Vitreous tugs on retina and causes retina to thicken slightly. Gives illusion that retina is elevated.
Who is likely to have white without pressure
AA older age.
White with pressure. How do you see this?
Have to do scleral indenter.
Difference between white with pressure and white without pressure
Thought to be histologically similar. Same prognosis and management as white without pressure.
Use scleral indenter to see white with pressure.
White with pressure through to have less potential to cause retinal breaks.
Retinoschisis 2 types
- Typical/flat (over 50% are this type)
2. Reticular/bullous
Typical/flat retinoschisis
- What causes it?
- Unilateral or bilateral
Splitting of neurosensory retina at outer plexiform layer. Closer to RPE.
Usually bilateral
Increased incident with age
Usually asymptomatic but shows scotoma on visual fields test
Retinoschisis Reticular/bulbar
- What causes it
- What does it look like
- Some have what appearance or are associated with?
- Filled with ___
Splitting of NFL Looks like a blister, balloon. Outer layer may show honeycomb pattern. Some have snowflakes on surface Some have associated retinal detachment Cavity thought to be filled with hyaluronic acid. Usually doesn't lead to any issues.
Pavingstone Degneration- other names
Primary chorioretinal atrophy
Cobblestone degeneration
Pavingstone degeneration is caused by what
Choriocapillaris occlusion with subsequent RPE and retinal tissue loss.
Pavingstone degeneration is located where
Nonpigmented areas between equator and ora serrata. Usually inferior
Majority found posterior to ora.
Pavingstone degeneration. Prevalent in who
People aging and in myopes.
Other names for retinal holes that do not have vetreoretinal traction
- location of hole
- What does it look like
Atrophic hole or retinal break
Located between equator and ora.
Less than 7% develop retinal detachment.
-2DD round, red lesion. pin point.
Other names for retinal holes that do have vetrioretinal traction
- Results from what
- What does it look like
- Location
Traction hole, percolated retinal hole.
- Result from abnormal vitreoretinal adhesion
- Looks like a round red hole with overlying floating fragment of tissue
- Occur between equator and ora.
