Ocular terminology Flashcards
Adduction versus abduction
- Adduction: toward the midline
- Abduction: away from the midline
Intorsion versus extorsion
- Intorstion: top of the eye rotates towards midline
- Extorstion: top of the eye rotates away from the midline
what are the three tunics of the eye?
- outer fibrous layer (scleral)
- middle vascular layer (choroid)
- inner neural layer (retina)
what is the outer fibrous tunic?
-connective tissue that forms the cornea and the sclera
what makes up the middle vascular tunic?
- iris
- ciliary body
- choroid
what makes up the inner neural layer?
-the retina (light capturing layer)
what are the three chambers?
- anterior
- posterior
- vitreous
where is the anterior chamber?
- bound by cornea in front
- bound by iris and anterior surface of the lens in back
where is the posterior chamber?
-behind the iris and adjacent to the lens
the anterior and posterior chambers are continuous through what? they both contain what?
- continuous through pupil
- contain aqueous humor that provides nourishment
where is the vitreous chamber?
-lies adjacent to the inner retinal layer and i bound in front by the lens
which chamber is the largest?
- vitreous
- makes up 80% of the volume of the eye
what is the average axial length?
23.3mm
myopia axial length
- eye is too long
- cornea and lens are too strong
- focus light in front of the retina
hyperopia axial length
- eye too short
- lens and cornea are weak
- focus light behind retina
emmetropic axial length
-cornea and lens strength matches the axial length of the eyeball
if the axial length is 26mm, the patient is likely? 22?
26-myopic
22-hyperopic
what is the fundus?
- interior lining of the eye
- including retina, optic disc, and macula
what is bulbar?
-term pertaining to the surface of the eye
what is palpebral?
-term pertaining to the eyelid
epithelial tissue is found where?
-either covering the external surface of a structure or lining of a cavity
epithelial cells are always associated with what?
a basement membrane that attaches them to underlying connective tissue
retinal pigment epithelium is associated with what membrane?
-Bruch’s membrane
corneal epithelium is associated with what membrane?
-Bowman’s membrane
what does connective tissue consist of?
- cells
- fibers
- ground substance
striated muscle is controlled by what system?
- motor nervous system
- voluntary movement
smooth muscle is controlled by what system?
- autonomic nervous system
- not voluntary movement
what is the only cranial nerve that is myelinated by oligodendrocytes?
optic nerve! CN 3
schwann cells/ oligodendrocytes/astrocytes
- schwann: PNS
- Oligodendrocytes:CNS
- astrocytes: blood brain barrier/CNS
which cells are myelinated and which are not?
preganglionic-myelinated
postganglionic-not myelinated
