Disorders Of Vision Flashcards
What are the basic cell types of the eyes?
Photoreceptor cels
Neuronal cells
Glial cells
What are the functions of rods & cones in the eyes?
Rods = perception of visual stimuli in subdued light
Cones = color discrimination & perception of stimuli in bright light
In De Myers loop, where does the lesion take place?
CL superior quadrant field deficit
What are the important parts of secondary visual processing?
Dorsal stream = accounts to the “where part”
Ventral stream = tells your brain the “what”
What condition develops upon interruption of the left optic tract?
Homonymous hemianopia
A lesion in the optic chiasm will manifest as?
Bitemporal hemianopia
In px with visual loss, what do you do?
- Visual acuity
- Inspect refractive media and optic fundi
- Testing of pupillary reflexes, color, vision
- Plottin gof visual field
- Check of preception of mootion, color, stereopsis, contour and depth
- Inquire and have px elabraote when they say they cannot see properly
What should be observed during fundoscopy?
red-orange reflex
clear media optic disc borders
cup-disc ratio
AV ratio?
What type of papilledema occurs when there is a loss of definition of vessels overlying the disc as they approach the margin of the disc from the periphery?
Mild papilledema
What type of papilledema occurs if there is a dome-shaped protrusions representing anterior expansion of the optic nerve head/
Fully developed papilledema
What is the important of seeing chronic paplledema + begging of optic atrophy?
Risk for permanent reduction in vision from secondary optic atrophy
What is the presentation of CHronic Papilledema + Beginning optic atrophy
Elevation of disc margin become less prominent & optic nerve head develops pallor representing a dropout of nerve fibers
What are the different diseases of the optic nerves?
Optic neuritis
Ischemic optic neuropathy or ischemic infarfction of the optic nerve head
Optic neuropathy caused by acute cavernouand paranasal sinus disease
Toxic and nutritional optic neuropathies
Hereditary abnormalities of the optic nerve
Compressions and infiltration by tumors
Radiation-induced optic nerve damage
What condition is Optic neuritis related to?
Optic neuritis
What is the most common cause of persistent monocular blindness?
Ischemic optic neuropathy
