Monday, November 26, 2012

Optic Nerve Under the Microscope

The optic nerve is the second of twelve paired cranial nerves and is considered part of the central nervous system. Fiber tracks of this central nervous system are incapable of regeneration unlike some in the peripheral nervous system, and therefore optic nerve damage can produce irreversible blindness. The fibers from the retina run along the optic nerve to nine primary visual nuclei in the brain where a major relay inputs into the primary visual cortex.

Illustration courtesy lithograph plate from Gray's Anatomy
Each human optic nerve contains between 770,000 and 1.7 million nerve fibers, which are axons of the retinal ganglion cells of one retina. 

Optic nerve captured at 40x magnification using the BA310 biological microscope and a 5 mega pixel CCD microscope camera.

Damage to the optic nerve typically causes permanent and potentially severe loss of vision. The three most common injuries to the optic nerve are from glaucoma, optic neuritis, and anterior ischemic optic neuropathy.

Optic nerve captured at 200x magnification using the BA310 biological microscope and a 5 mega pixel CCD microscope camera.