List the three layers of the eye.
- Outer - Sclera
- Middle - Choroid
- Inner - Retina
State briefly the functions and location of the Sclera.
- Outer layer of eye.
- Protection and forms shape of the eye.
State briefly the functions and location of the Cornea.
- Outer layer of eye.
- At the center of sclera, tough transparent, first structure that light travels through.
State briefly the functions and location of the Iris.
- Middle layer of eye.
- Circular muscle, color of eye and regulates the amount of light entering the eye.
State briefly the functions and location of the Choroid.
- Middle layer of eye.
- The blood supply of eye, where the nerves are.
State briefly the functions and locations of the Retina.
- Inner layer of eye.
- Made of specialized nerve cells called rods and cones.
State briefly the functions and location of the Optic Nerve.
- Inner layer of the eye.
- Carriers electrical impluses to the brain.
Which structure give us most acute vision especially color?
Name for the opening in the center of the Iris.
State pupil size in presence of dim light.
Dim light the pupil is large and dilated.
State the pupil size in presence of bright light.
Bright light the pupil is small and constricted.
State name of thin membrane (film) which covers the eyeball and protects it.
State function of the lacrimal gland.
Manufactures tears which help destroy bacteria and viruses that may enter the eye.
Describe the location of the Anterior cavity.
Extends from Cornea to the Lens.
Describe the location of the Anterior chamber.
Extends from the Cornea to the Iris.
Describe the location of the Posterior chamber.
Extends from the Iris to the Lens.
Describe the location of the Posterior cavity.
Extends from the Lens to the Optic nerve.
State functions of the lens.
The lens main function is focusing, which is called accommodation.
State the location and function of the Canal of Schlemm.
- Located at the top and bottom of the cornea.
- Is the structure that drains the aqueous humor.
Trace the pathway of light traveling into the eye.
- Optic nerve.
State the area of the brain in which vision occurs.
State the meaning of Blephar.
State the meaning of Ambly.
State the meaning of Presby.
In which disease is choroidal hemorrhage so common?
Describe a cataract.
The lens becomes opaque and vision diminishes.
Briefly describe macular degeneration.
- Gradual degeneration of the cones.
- Progressive, related to aging and no cure.
- Lost of central vision.
Briefly define papilledema.
- Accumulation of fluid around the optic nerve the brain.
- Causes temp. blindness
Give a brief definition of amblyopia.
Poor vision in one eye without a detectble cause. (dimness)
Give a brief definition of presbyopia.
Visual loss due to aging.
A condition in which too much pressure is created in the eye by excessive aqueous humor. This excess pressure can lead to permanent damage of the optic nerves, resulting in blindness.
Give 2-3 symptoms of glaucoma.
- Visual loss
- Halos around electric lights
- Cloudy vision
State instrument used to detect glaucoma.
Tonometer used to test intraoccular pressure.
- Is an abnormal curvature in the cornea.
- objects to appear warped/distorted
When the optic axis fails to fall on the same object *cross eyed*.
Removal of the eyeball.
- Pink eye
- Inflammation & infection of conjunctiva
Define ophthalmia neonatorum.
- If mother has gonorrhea, it can cause blindness in newborn.
- Ilotcin are drops given immediately after birth to newborns to prevent blindness.
Expalin the blind spot.
Why is it called that?
What is the proper name for this area?
- This is where the retina merges into the optic nerve.
- There are no exposed rods and cones in this area.
- Optic disc
Medical term for Focusing.
Medical term for bending of light rays.
What controls the shape of the lens?
Where do we find Aqueous Humor?
It flows through the anterior & posterior chambers.
What is the function of the Aqueous Humor?
It is where the nutrients are that supply the structures of the anterior cavity.
Where do we find Vitreous Humor?
It is found in the posterior cavity.
What is the function of Vitreous Humor?
It is responsible for refraction, which is the bending of light.
What are rods and cones?
They are specialized nerve cells located in the retina.
What type of vision are rods responsible for?
Black & White vision
What type of vision are cones responsible for?
State the structures of the Outer ear and it's function.
- Pinna external flap cartilage & collects the sound waves.
- External auditory meatus- opening of auditory canal.
- Auditory Canal- tube shape and lead to the tympanic membrane, it carries the sound waves toward the middle ear.
What are the parts of the Pinna?
- Helix- folded portion.
- Tragus- lead toward the lobe
State the structures of the middle ear and their functions.
- 1. Typmanic membrane (ear drum)- separates external from middle ear
- Vibrates in response to sound waves.
- 2. Ossicles (tiny bones) malleus, incus, stapes
State the structures of the inner ear.
- Oval Window
- Round Window
- The entire inner ear is filled with auditory fluid.
- The fluid is called perilymph and the endolymph
State the structures lined with ceruminous glands and function of cerumen.
- The auditory canal is lined with cerumen glands.
- Cerumen (earwax) filters, lubricates and protects the ear from dirts, dust and microbes.
State the function of eustachian tube with reference to tympanic membrane.
- The auditory tube that connects the midde ear to the throat.
- It helps maintain equal pressure on both sides of eardrum.
What structures are responsible for maintenance of equilibrium? Where?
The semicircular canal and the vestibule are responsible for equilibrium, in the inner ear.
Trace sound waves from pinna to temporal lobe of the brain.
- tympanic membrane
- inner ear
- auditory nerve
- temporal lobe of brain
Abnormal ringing in ear, damage to the auditory nerve
- Hearing loss because of the aging process.
- loss of hair in the organ of corti
Is the immobilization of the stapes within the inner ear, which is a common cause of conductive hearing loss.
- Is a surgical procedure in which the innermost bone (stapes) of the three bones of the middle ear is removed.
- Replaced with a small plastic tube surrounding a short length of stainless steel wire (a prosthesis). To improve hearing.
Define Meniere's Syndrome
- An inner-ear disease characterized by attacks of vertigo, tinnitus and nausea.
- Permanent hearing loss may result.
Define Auditory agnosia
- The impaired recognition of non-verbal sounds and noises.
- Inability to recognize or understand the meaning of spoken words.
Define Otitis media
Is a middle ear infection. (inflamation of the middle ear)
Describe the appearance of Normal eardrum
Very thin, beige, shiny
Describe the appearance of an infected eardrum.
It would be red.
Describe the appearance of an eardrum with fluid behind it.
The eardrum would be dull.
Units for measuring the relative intensity of sounds on a scale from 0 to 130.
- Is the number of complete fluctuations of energy per second in the form of waves.
- The pitch of sound.
The folded portion of the pinna
Medical term for ear pain.
Surgical puncture of the tympanic membrane, as for the removal of fluid or the drainage of pus. Also called tympanostomy, tympanotomy.