What is lamina cribrosa?
The lamina cribrosa (LC) is a mesh-like structure at the optic nerve head that surrounds and supports the retinal ganglion cell axons as they form the optic nerve. 1–3. Deformation and displacement of the LC have been increasingly implicated as the primary pathophysiologic mechanism of glaucomatous optic neuropathy.
What is lamina cribrosa of sclera?
The lamina cribrosa sclerae, also known as lamina cribrosa of the sclera, is a net-like structure covering a small hole in the posterior sclera through which the optic nerve (cranial nerve II), central retinal artery and central retinal vein pass.
What is lamina in the eyes?
The nerve fibers forming the optic nerve exit the eye posteriorly through a hole in the sclera that is occupied by a mesh-like structure called the lamina cribrosa. It is formed by a multilayered network of collagen fibers that insert into the scleral canal wall.
What is located in the fovea?
Fovea: In the eye, a tiny pit located in the macula of the retina that provides the clearest vision of all. Only in the fovea are the layers of the retina spread aside to let light fall directly on the cones, the cells that give the sharpest image. Also called the central fovea or fovea centralis.
Why is the lamina cribrosa the weakest part of the sclera?
Being structurally weaker than the much thicker and denser sclera, the lamina cribrosa is more sensitive to changes in the intraocular pressure and tends to react to increased pressure through posterior displacement….
| Lamina cribrosa sclerae | |
|---|---|
| Details | |
| TA98 | A15.2.02.011 |
| FMA | 58371 |
| Anatomical terminology |
Why is it called lamina cribrosa?
This is thought to be one of the causes of nerve damage in glaucoma, as the displacement of the lamina cribrosa causes the pores to deform and pinch the traversing nerve fibers and blood vessels….
| Lamina cribrosa sclerae | |
|---|---|
| Details | |
| Latin | lamina cribrosa sclerae |
| TA98 | A15.2.02.011 |
| FMA | 58371 |
Where is the lamina Papyracea located?
the ethmoid bone
The lamina papyracea, also known as the orbital lamina of the ethmoid bone, is the principal component of the medial wall of the orbit, and also the lateral surface of the ethmoid air cells.
What is macula and fovea?
Fovea: The pit or depression at the center of the macula that provides greatest visual acuity. Foveola: the foveoala lies in the center of the fovea and contains only cone cells, Macula: The portion of eye at the center of the retina that processes sharp, clear, straight-ahead vision.