Abstract
Purpose: :
Untreated papilledema from pseudotumor cerebri (PTC) can result in significant visual morbidity. An objective assessment of retinal nerve fiber layer (RNFL) loss would be invaluable in pseudotumor cerebri. Scanning laser polarimety (SLP) measures form birefringence properties of the RNFL and offers a theoretical advantage of potentially assessing axonal loss in the setting of concurrent nerve fiber edema.
Methods: :
Thirty three eyes of seventeen patients with active disc edema from PTC without clinical evidence of optic nerve atrophy underwent SLP (GDx ECC) generated measurement of the RNFL and were compared with the age-matched normative database. A qualitative evaluation of concurrent optical coherence tomography imaging in the same patients was conducted.
Results: :
The average RNFL thickness (TSNIT average) for patients’ eyes (65.5 microns) was significantly elevated compared to the normative average (55.6 microns; p < 0.001). The superior and inferior quadrants were the most commonly elevated. Seven of thirty-three eyes had observable intraretinal edema into the macula, but in all cases this was mild and outside of the fovea.
Conclusions: :
RNFL parameters were elevated in non-atrophied nerves from PTC patients compared to the normative data set. While SLP does provide a quantifiable measurement of RNFL thickness in papilledema from PTC, it does not appear free of confounding by axonal swelling.
Keywords: optic nerve • imaging/image analysis: clinical • neuro-ophthalmology: optic nerve