These dorsal eyes are very perfect in elaboration, possessing lens, retinal nerve-end cells, retinal pigment and optic nerve.
Another cartilage or ossification, the posterior sclerotic ring, occurs within the walls of the posterior portion of the cup, and surrounds, especially in the Pici and in the Passeres, the entrance of the optic nerve.
Curiously enough, however, they differ from the cephalic Molluscan eye in the fact that, as in the vertebrate eye, the filaments of the optic nerve penetrate the retina, and are connected with the re surfaces of the nerve-end cells nearer the lens instead of with the opposite end.
Hickson and others, that in the bivalves Pecten and Spondylus, which also have eyes upon the mantle quite distinct from typical cephalic eyes, there is the same relationship as in Oncidiidae of the optic nerve to the retinal cells.
The lateral eyes are in Limulus " compound eyes," that is to say, consist of many lenses placed close together; beneath each lens is a complex of protoplasmic cells, in which the optic nerve terminates.
But they also receive the nerve fibres of the optic nerve.
nerv.f, Nerve fibres of the optic nerve.
Thus light, pressure, or mechanical stimulation acting on the retina and optic nerve invariably produces luminous impressions.
He has bilateral optic nerve atrophy, which affects the visual information passing from the eye to the brain.
At the optic chiasm about half of the visual information in each optic nerve swaps over to the opposite nerve.
fibre optic nerve is made up of thousands of nerve fibers.
ganglion cells form the optic nerve.
Some people may know the visual side alone as optic nerve hypoplasia.
The optic nerve is made up of thousands of nerve fibers.
Despite the large number of the optic nerve fibers their capacity of plasticity for to achieve recovery is rather limited.
The joined up path that signals travel down from retina to optic nerve then optic chiasm then occipital lobe is called the visual pathway.
At the optic chiasm about half of the visual information in each optic chiasm about half of the visual information in each optic nerve swaps over to the opposite nerve.
A really high pressure will damage the optic nerve immediately.
In the visual pathway the fibers of the retinal ganglion cells form the optic nerve.
The left optic nerve also enhanced (not shown ).
Endoscopic orbital decompression may be used to treat disfiguring proptosis or sight threatening optic nerve compression in patients with thyroid eye disease.
They agree with the dorsal eyes of Oncidium (Pulmonata) in the curious fact that the optic nerve penetrates the capsule of the eye and passes in front of the retinal body (fig.
One of the leading causes of vision loss among senior citizens is the progressive, irreversible damage caused to the optic nerve by glaucoma.
The retina transforms the image it receives into electrical signals that are sent to the brain via the optic nerve.
Some centers may use chemotherapy in place of radiation therapy when the tumors are too large to be treated by local therapies or are found over the optic nerve of the eye.
This leads to increased pressure within the eye and eventual damage to the optic nerve.
You should also avoid B12 if you suffer from Leber's disease as supplementation could lead to serious damage to the optic nerve including blindness.
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