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Translaminar Autonomous System Model for the Modulation of Intraocular and Intracranial Pressure in Human Donor Posterior Segments
Published on: April 24, 2020
Papilledema revisited: is its pathophysiology really understood?
Hanspeter E Killer1, Gregor P Jaggi, Neil R Miller
1Department of Ophthalmology, Kantonsspital Aarau, Aarau, Switzerland. killer@ksa.ch
Clinical & Experimental Ophthalmology
|July 24, 2009
Summary
Papilledema, optic disc swelling, may not solely result from increased intracranial pressure (ICP). Compartmentalization of the optic nerve
Area of Science:
- Neuroscience
- Ophthalmology
Background:
- Papilledema is optic disc swelling linked to increased intracranial pressure (ICP).
- ICP is typically measured via lumbar puncture, assuming uniform cerebrospinal fluid (CSF) pressure.
- Existing models fail to explain varied papilledema presentations despite ICP.
Purpose of the Study:
- To investigate alternative mechanisms beyond elevated ICP in papilledema.
- To explore the role of optic nerve subarachnoid space (ON SAS) dynamics.
Main Methods:
- Analysis of CSF composition and pressure in lumbar and ON SAS.
- Comparison of CSF in patients with and without papilledema.
- Assessment of lipocalin-like prostaglandin D synthase concentrations.
Main Results:
- Some patients with papilledema show normal ICP and asymmetrical swelling.
- Elevated concentrations of astrocyte-toxic lipocalin-like prostaglandin D synthase found in ON SAS.
- Differences in CSF dynamics observed between lumbar and ON SAS in some patients.
Conclusions:
- Papilledema may arise not just from elevated ICP, but also from ON SAS compartmentalization.
- Localized toxic milieu within the ON SAS could contribute to papilledema.
- This suggests a localized mechanism for optic nerve dysfunction in certain cases.
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