exam 1 Flashcards
what is the average size of optic nerve
whats considered small, large?
1.99 X 1.77
horizontally: 1.77
vertical: 1.99
small: <1.5
large: >2.22
axons from what cell form nerve fiber layer?
what about the optice nerve?
ganglion axons for both
whats the conversion factors when using slitlamp slit to measure optic nerve size
60 lens 1
78 lens1.1
90 lens 1.3
in mal inserted optic nerve what is raised or flat
temporal is flat nasal raised
Optic nerve is located in what cell layer
ganglion cell layer
what is the paillomacular bundle
whats its significance to GLC
bundle of macular fibers that enter temporally of the ON
damage occurs here before optic nerve
meninges
which meninges is made of
- thin collagen
-vascular CT
-dense CT
what space holds CSF
which meninges is made of
- thin collagen
arachnoid
-vascular CT
pia mater
-dense CT
dura matter
sub arachnoid space holds CSF
what nerve fibers decussates at the optic chiasm
nasal
intraocular segment
starts where and ends where?
whats its 2 sections
-where do these 2 sections start and end?
which section has glial or astrocytes bundles
intraocular segment
starts where and ends where?
ONH to the lamina cribosa
whats its 2 sections
1. prelaminar
HAS GLIAL AND ASTROCYTES
2. Laminar
-where do these 2 sections start and end?
1. prelaminar
optic nerve head to lamina crib
2. Laminar
globe to lamina cribosa
what ON segment is S shaped
intraorbital
what ON segment starts to be mylinated with what cells
intraorbital with oligodendrocytes
muscle attatchment occurs in what ON segment and what muscles
intraorbital MR SR
purpose of astrocytes
ion concention regulator
structure
glycogen storage
what ON segment goes through optic canal
intracanalicular
Intracranial ON segment extends from what to where
what is its surrounding structures
Intracranial ON segment extends from what to where
optic canal to the optic chiasm
what is its surrounding structures
-internal carotid art
-sphenoid sinus
-ACA anterior cerebral artery
list the shortest to longest ON structures
- intraocular
- intracanalicular
- intracranial
- intraorbital
name the blood supply to the optic nerve segments
- intraocular
-short posterior cilliary arteries
-circle of zinn haller
2.intraorbital
-pial
-central retinal artery
- intracranial
-anterior communicating art
-anterior cerebral artery
-internal carotid
ON sheath meningioma occurs in what segments
introrbital intracanalicular
f>M
optociliary shunt vssels (collaterals
ON head edema and atrophy
painless
tx radiation or excise or monitor
What ventricle is superior to optic chiasm
where is the pituitary in relation to the optic chiasm
3rd
pituitary is 1 cm below optic chiasm
where is the compression located with a pituitary adenoma
what kind of VF defect can occur
near decussation
bitemporal
LGN
location
function
shape
what cells synapse here
Binocular processing (Y/N)?
LGN
location
-thalamus
function
-process and filter to send to visual cortex
-NO BINOCULAR PROCESSING
shape
-cone
what cells synapse here
-ganglion
what layers of the LGN are
mangocellular
parvocellular
koniocelular
what cells are ipsi and contralateral
what layers of the LGN are
mangocellular
1-2
parvocellular
3-6
koniocelular
all
“see I , I see, I see/ CIICIC”
Contralateral - 1,4,6
ipsilateral - 2,3,5
where does binocular processing occur
what layer receives input and what layer fives inhibitory feedback
Brodman area 17 primary visual cortex
layer 4 recieves input from LGN
Layer 6 gives inhibitory feedback to LGN
there are 6 layers total
the primary visual cortex is seperated by what fissure.
what gyrus is inferior and superior
calcarine
cuneus gyrus upper portion
Lingual gyrus lower portion
what is the blood supply for the following
optic chiasm
optic tract
LGN
Optic radiations
Visual Cortex
optic chiasm
-circle of willis
optic tract
-anterior choroidal art
LGN
-anterior choroidal art
-posterior cerebral art
Optic radiations
-anterior coroidal
-posterior cerebral art
-middle cerebral
Visual Cortex
-posterior cerebral art
-middle cerebral
V1 sends basic stimuli to what?
where is this located
V2-V5
lateral aspects of the occipital lobe
name the layers of buches membrane
- BM of choriocapillaris
- outer collagenous zone
- elastic
- inner collagenous zone
- BM of RPE
the uvea attaches to what 3 things
- scleral spur
- vortex veins
- optic nerve
suprachoroid space holds what
long posterior ciliary nerves and art
what layer of the choroid are hallers and sattlers layer in? distinguish difference bewteen them
hallers
-large BV that go into smaller bv that form sattlers
sattlers
-small bv that form capillary bed
all in choroid stroma
what layer of the choroid is associated with
-loose CT
-LPCA LPCN
-single layer of anastomosing fenestrated capillaries
-thin
-controlled by autonomic nervous system (explain symp and parasymp effects)
-fuses with retina
-denses at macula
-increase in thickness with age
-decreases in thickness with age
-hallers and scattlers layer
—–loose CT —-
choroidal stroma
—–LPCA LPCN—
suprachoroid lamina
—–single layer of anastomosing fenestrated capillaries ———-
choriocapilaris
——thin———-
buchs membrane
——controlled by autonomic nervous system (explain symp and parasymp effects) ——-
choroidal stroma - sympathetic vaso constrics and para vaso dilates
—–fuses with retina —-
bruches
——denses at macula——
choroidal capillaries
——increase in thickness with age —-
bruches
—-decreases in thickness with age—-
choroidal capillaris
—-hallers and scattlers layer—–
choroidal stroma
how many vortex veins per eye?
what layer of choroid
4-6
where does the choroidal capillaris terminate?
what do capillaries of this layer contain
ONH
- pericytes
- BM (lamina)
- endothelial cells
DM damages what cells and in what layer
in the choroid
pericytes and endothelial cells
what does pericytes do
they are associated with what layer of the choroid
they are located in the choriocapilaries layer of the choroid
regulated local blood flow
buches membrane includes two layers that are BM what what other layers of the choroid
choriocapillaries and RPE
RPE cell… where does it face
basal side
apical side
basal side is facing bruches
apical (cilliary processes) side faces sensory photoreceptors
what 2 layers are commonly separated in a RD
what caused this
RPE and neural (sensory), due to embryological development
what layer forms blood brain barrier
RPE
what layer of the retina has lots of melanosomes
RPE
what disease is related to impaired tyrosinase enzym activity?
this results in missing or loss of what
albinism
loss of RPE
what is lipofuscin
where does it accumulate
what disease is this
incomplete phagocytosed particles in lysosomes of the cell
stargardts diesase
inherited macular dystrophy
what are halocytes and where are they found
they are cells that release antiangiogenic factors in the vitreous humor
they are phagocytic
what is shafer signs
tabacco dust in anterior vitreous that are rpe cells that could mean hole/RD
where is the weakest and strongest attachments for anterior vitreous
where else does it attach too
where is the most common location of detattchment
what layers of the vitreous fibers does it attach to
weakest: blood vessels
strongest: near orra serrata (vit base)
optic disc, macula, posterior lens
RD common at vitreous base because even though it is the strongest it tugs
attaches to nonpigmented ciliary epi
internal limiting membrane
what is wiegers ligament?
whats the space inside of it?
what is annular ring of attachment?
ring of attachment of anterior vit to posterior lens
space inside it is bergers space or rentrrenticular space
what is annular ring of attachment?
attachment of vit to macula
list areas of attachment of vitreous from strongest to weakest
- vitreous base
- posterior lens
- optic disc
- macula
- blood vessels
what is cloquet canal
it is the canal that is a remnant of the hyaloid artery during development
it supported the early development of the lens
it is in the central zone of vitreous
what zone of the vitreous has the least amount of collagen?
what zone has tighlty packed collagen
least amount in central
tightly packed is cortex
what is bergmeisters papillae
glial tissue on the optic disc
posterior attachment of hyaloid artery
what are epicapsular stars
remnants of tunica vasculosa lentis gold flakes on anterior lens
asteroid hyalosis is made of collection of what
symptoms?
one or both eye?
calcium pyrophosphate globules
no symptoms benign
unilateral
what is synchysis scintallans
symptoms?
one or both eye?
cholesterol crystals in vitreous
no symptoms
bilateral
3rd decade of life
what is moors lightening streaks
vertical lightening streaks that a pt sees temporally when moving head, it is benign
