Intro to Ophthalmology Flashcards
What makes up the fibrous layer? Is it in the outer, middle or inner layer?
Sclera and cornea
outermost layer
What makes up the vascular layer? Is it in the outer, middle or inner layer?
Iris
Pupil
Ciliary Body
Choroid
middle layer
What makes up the neural layer? Is it in the outer, middle or inner layer?
retina and optic nerve
inner
What are the two sections of the retina? what is the function?
outer pigmented layer
inner neural layer: house the photoreceptors that perceive light and send the neural signals
Where is the light focused?
light is focused at the back of the eye
**What are the 3 different chambers of the eye?
Anterior chamber: cornea to the iris
posterior chamber: iris and the lens (very narrow)
vitreous chamber: lens to the back of the eye
**What are the two SECTIONS of the eye? What is the job of each section?
anterior section: filled with aqueous humor (watery) provides nutrients
posterior section: filled with vitreous humor (jelly like) provides support and structure
**What chambers are in the anterior section? posterior section?
anterior chamber and posterior chamber
posterior: vitreous chamber
_______ the pigmented part of the retina located in the very center. _____ is in the center of the macula. Why is this important?
macula: responsible for vision straight ahead
fovea
The fovea is the area of best visual acuity. It contains a large amount of cones—nerve cells that are photoreceptors with high acuity.
Describe how sight works
-light reflects off an object and enters the eye (as it enters the eye, light is unfocused)
-then hits the cornea, iris, pupil: where the light enters the eye
-lens: focuses the light
-light then falls onto the retina
-optic nerve then carries those signals to you brain where they are decoded into an image
**to see near objects, how does the lens adapt? to see objects far away?
lens becomes thicker and focal length of lens decreases
lens becomes thinner and focal length of lens increases
_____ this is where light focuses precisely on the retina
For good vision, the _____ must be on the retina
focal point
focal point
_____ The process of bending light to produce a focused image on the retina. Most vision problems occur because of an error in how our eyes ____
Refraction
refract light
____ is nearsighted
____ is farsighted
myopia: nearsighted
hyperopia: farsighted
____ is too much curvature of the cornea. Eyeball is _____ for the refractive power of the cornea and lens. Focus point is ___ of retina.
myopia: Nearsightedness
too long
in front of the retina
**How do you correct myopia?
Correct with concave lens
Wide view lens
Diverges light rays
Makes objects look smaller than they are
_____ is too little curvature of the cornea. Eyeball is ____ for the refractive power of the cornea and lens. Image is focused ____ the retina.
Hyperopia
too short
behind the retina
**How do you correct for hyperopia?
Correct with convex lens
The rays meet at a single point on other side of lens
Magnify objects to make them look larger
Spreads out light rays
divergent
Focal point in front of lens
Parallel rays of light pass through the lens are spread out
Image formed is smaller but clear
Gives wider viewing angle
What type of lens?
concave
Focuses the light rays to a specific point
Convergent
Rays of light passing through it get bent in a inward direction towards a single point
Brings light rays together to a focal point behind the lens
Convex lenses hold magnifying abilities
What type of lens?
Convex
Irregular shape of the cornea or lens
Not perfectly spherical, kind of like a football
Light reflected to multiple areas of retina = multiple focal points
Retinal image is blurred
What eye condition?
How do you correct it?
Astigmatism
Corrected with cylindrical lenses that equalize the refraction of light
When is astigmatism worse?
worse at night and in low light conditions
____ is age related farsightedness. Loss of mobility and focusing power of lens. What age do you begin to notice it? until what age?
presbyopia
44-46 years old and symptoms increase until about age 55 then stablize
correct with reading glasses
Cornea becomes thin and cone-like
Causes blurred vision
Causes sensitivity to light and glare
What am I?
When does it develop?
What 3 things are sometimes found in the pt hx?
Keratoconus
develops at puberty or early adulthood
pt hx: Corrective lenses, contact lenses, cornea transplant
_____ are specialized for dim light (night vision)
_____ are specialized for color perception
Red, green and blue cones
Color blindness results from deficit of one type of ____
Rods
Cones
**Aqueous humor is produced in the _____. Anterior cavity between the ___ and ____. What is its job?
_____ and ____ do not have blood vessels
**Aqueous humor also maintains ______
ciliary body
cornea and lens
supplies nutrients to cornea and lens
cornea and lens
maintains intraocular pressure
Vitreous humor is found where?
What is the consistency?
What is its job?
Posterior cavity between lens and retina
Jelly Like substance
Maintains shape of eyeball
Holds retina in place
What are two additional names for narrow angle glaucoma? Open angle?
closed angle
acute angle closure glaucoma
Chronic glaucoma
_____ A group of eye diseases characterized by neuropathy to the optic nerve. What is a common exam finding?
Glaucoma
cupping
_____ is the second leading cause of blindness next to cataracts
glaucoma
**Where is the lesion?
lesion is BEFORE the optic chiasm
blindness in the R eye
**What is this called? Where is the lesion?
bitemporal hemianopsia
lesion AT the optic chiasm
**What is this called? Where is the lesion?
L homonymous hemianopsia
after optic chiasm
Pupillary reactions are controlled by what 4 things?
Parasympathetic constriction
Sympathetic dilatation
Controlled by the sphincter and dilator pupillae muscles
Light
When evaluating pupillary reaction, what are you looking at? Where does the pt need to look?
Magnitude
Speed
Symmetry
pt need to focus on a far object NOT your light!
_____ when one pupil is larger than the other
anisocoria
Small pupil is abnormal if anisocoria is greater in dark than light = abnormality in _____
sympathetic system
Larger pupil is abnormal of anisocoria is greater in light than dark = abnormality in _____
parasympathetic system
What is a Relative Afferent Pupillary Defect? What is another name for it?
What is the test called?
What are 3 conditions in which it is common?
No direct response but normal consensual response
Marcus Gunn Pupil
Swinging eye flashlight test
inflammation, optic nerve lesion, glaucoma
What is anisocoria? What will the pupillary reaction to light be? What are some common sources of the problem?
Asymmetric size of pupils
Has No, or sluggish pupillary reaction to light
Horner’s syndrome
Adie’s syndrome
injury
lesion
**What is Horner’s Syndrome?
loss of sympathetic innervation due to a lesion along the sympathetic pathway that causes:
Ptosis (drooping of the eyelid)
Anhidrosis (not sweating)
Miosis (constricted pupils)
What is Adie’s pupil? what is another name for it? What age group?
No or sluggish pupillary reaction to light
Direct and consensual
Can be associated with diminished DTRs
Tonic Pupil
women in 30s and 40s
What is the Argyll-Robertson Pupil? What dz is it the hallmark presentation for?
Pupils restrict to accommodation, but not light
Hallmark of tertiary neurosyphilis
usually bilateral
_____ is loss of transparency. Name some additional signs
Cataract
blurred vision
painless
absence of red reflex
When viewing the fundoscopic exam, ____ are thinner than ____
arteries are thinner than veins
____ necessary for sharp, central vision
Reading, driving, any activity where visual details are needed
Provides greatest visual acuity of all
fovea
___ is the functional center of the retina
Responsible for the central, high-resolution, color vision that is possible in good light
In your direct line of sight
macula
_____ are small, yellow-white, slightly elevated lesions, which look like clouds on ______. What 2 dz are they most common with?
Cotton Wool Spots (AKA soft exudates)
retinal surface
diabetic retinopathy and hypertensive retinopathy
_____ is often described as wall paper falling off a wall. What dz?
retinal detachment
diabetic retinopathy
_____ is swelling of optic nerve. Describe it
Papilledema
looks elevated and swollen with ill defined margins
_____ is widespread retinal hemorrhages. Often described with venous dilation and tortuosity. What is the clinical pearl?
Retinal Vein Occlusion
blood and thunder fundus
Central retinal artery occlusion often has ____ and ____ seen on fundoscopic exam
Cherry Red Spot on fovea
Boxcar Segmentation
_____ a small artery is seen crossing a small vein. This causes compression on the small vein. Will show bulging on either side. What dz?
A-V nicking
HTN retinopathy
Copper and silver wiring is seen in what dz? What is it due to??
HTN retinopathy
Both due to atherosclerotic vessel wall thickening and chronic Hypertension
____ is moderate vascular wall changes and appears orange or yellow instead of red
Copper wiring
____ is severe vascular wall hyperplasia and thickening. Appears white
silver wiring
____ is when optic nerve is damaged in ___ these nerve fibers die off and blood flow is diminished. This causes ____ to become larger since the support structure is not there
Cupping
Glaucoma
cup
aka the cup takes up a larger portion of the optic disc than it should. See picture
____ are smallish, yellowish-whitish distinct spots with sharp borders. Caused by breakdown of blood-retina border, allowing leakage from retinal vessels. See all over the retina. What dz?
Hard Exudates
Diabetic Retinopathy
____ happen when necrotic vessels bleed into the nerve fiber layer. More superficial layers of the retina. larger. What dz?
Flame Hemorrhages
Diabetic and HTN retinopathy
_____ Occur as microaneurysms rupture in the deeper layers of the retina. Blood accumulates in the inner nuclear layer. What dz?
Dot-Blot hemorrhages
DM and HTN
____ are microvascular damage and ischemia cause release of vasoproliferative factors (Vascular Endothelial growth Factor). This results in new vessel from the adjacent retinal vessels in an attempt to revascularize the diseased tissue. What dz?
Neovascularization
DM and wet macular degeneration
____ are yellow deposits under the retina
Made up of lipids and proteins
Scattered around macular region
“Tombstones” of dead retinal epithelium.
Appear in a layer of the retina called ____.
What dz?
Retinal Drusen
Bruch’s membrane
Age-related macular degeneration
_____ looks at structures in anterior chamber. Provides greater magnification (10 to 25 times) and illumination
slit lamp examination
_____ is used to look for foreign bodies, ulcers and corneal abrasions
fluorescein staining
