Papilledema pathophysiology: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
No edit summary |
||
Line 5: | Line 5: | ||
==Overview== | ==Overview== | ||
[[Papilledema]] results due to transmission of [[increased intracranial pressure]] to the anterior end of [[optic nerve]] through optic nerve sheath. | [[Papilledema]] results due to transmission of [[increased intracranial pressure]]<ref>{{cite journal |author=Tso MO, Hayreh SS |title=Optic disc edema in raised intracranial pressure. IV. Axoplasmic transport in experimental papilledema |journal=Arch. Ophthalmol. |volume=95 |issue=8 |pages=1458–62 |year=1977 |month=August |pmid=70201 |doi= |url=}}</ref> to the anterior end of [[optic nerve]] through optic nerve sheath. | ||
==Pathophysiology== | ==Pathophysiology== |
Revision as of 00:26, 18 July 2012
Papilledema |
Diagnosis |
---|
Treatment |
Case Studies |
Papilledema pathophysiology On the Web |
American Roentgen Ray Society Images of Papilledema pathophysiology |
Risk calculators and risk factors for Papilledema pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-In-Chief:Kalsang Dolma
Overview
Papilledema results due to transmission of increased intracranial pressure[1] to the anterior end of optic nerve through optic nerve sheath.
Pathophysiology
- Optic nerve sheath is continuous with the subarachnoid space of the brain and is regarded as an extension of the central nervous system.
- The cranium and the vertebral body, along with the relatively inelastic dura, form a rigid container, such that the increase in any of its contents—brain, blood and cerebrospinal fluid can cause increased intracranial pressure.
- The brain itself is relatively spared from pathological consequences of high pressure.
- Increased intracranial pressure is transmitted through to the optic nerve via this optic nerve sheath.
- The anterior end of the optic nerve stops abruptly at the eye. Hence the pressure is asymmetrical and this causes a pinching and protrusion of the optic nerve at its head.
- The fibers of the retinal ganglion cells of the optic disc become engorged and bulge anteriorly.
- Persistent and extensive optic nerve head swelling, or optic disc edema, can lead to loss of these fibers and permanent visual impairment.
- Papilledema may be absent in cases of prior optic atrophy. In these cases, the absence of papilledema is most likely secondary to a decrease in the number of physiologically active nerve fibers.