|
| |
|
|
| The
optic nerve is composed primarily of axons from the retinal ganglion
cells. In addition, there are
multiple glial support cells and tissue in the nerve itself.
The optic nerve begins at the optic nerve head or disc (#21872,
#21869) and passes through the sclera in the area of the lamina cribrosa
and then extends through the orbit and optic canal to the chiasm.
Posterior to the lamina cribrosa, the optic nerve is surrounded by
a three- layered meningeal sheath similar to the central nervous system
which consists of a dura (optic nerve sheath), arachnoid, and pia.
The subarachnoid space is in direct communication with the
subarachnoid space of the central nervous system.
The central retinal artery and vein penetrate the optic nerve and
enter the eye from the center of the disc.
The optic nerve receives its blood supply mainly from vessels that
originate in the ophthalmic artery.
-(#44418,
#44419, #44420) are of normal optic nerve.
|
| Low
Power #21872 |
Low
Power #21869 |
|
|
| Med.Power
#22083 |
|
 |
|
|
|
|
