Abstract
Purpose: :
To assess axonal loss in patients entered into the optic neuritis treatment trial (ONTT).
Methods: :
The Optic Neuritis Treatment Trial randomized 389 patients with acute optic neuritis to intravenous methylprednisolone (IVMP), oral prednisone or placebo treatment arms. We measured serum pNF-H levels in 175 ONTT patients. 63 patients received IVMP, 63 patients received prednisone and 49 patients received placebo. Venous blood was drawn 5 years after enrollment. Optical coherence tomography (OCT) was performed 10 years later.
Results: :
Post-hoc least significant difference tests revealed lower pNF-H with IVMP relative to placebo (difference = -0.067; p = 0.047) or prednisone (difference = -0.073, p= 0.021). There was no difference (p = 0.75) between cases with or without MS at 5 years. A subset of 51 patients had retinal nerve fiber layer (RNFL) measurements at year 15 that constituted another outcome variable. There was no significant difference of mean IVMP RNFL=81 µm (n= 18), 78 µm with prednisone (n=18) or 71 mm placebo (n=15). In the subset with RNFL measurements of affected and non-affected eyes of patients with CDMS (n=20), respectively 69 mm and 82 mm, were significantly different (respectively p=0.018 and p=0.001) from those without CDMS, respectively 83 µm and 99 µm (n=31). There was no correlation of the number of T2W MRI brain lesions to pNF-H levels. We found no statistical correlation of pNF-H levels to recovery of visual acuity at 6 months or RNFL thickness at 15 years in patients with or without MS.
Conclusions: :
We conclude that IVMP had a small but measurable effect on suppressing neurodegeneration in optic neuritis.
Keywords: neuropeptides • optic nerve • neuro-ophthalmology: optic nerve