Gabilondo, I. 1 , Martínez-Lapiscina, E. 1 , Fraga-Pumar, E. 1 , Ortiz-Perez, S. 2 , Torres-Torres, R. 2 , Andorra, M. 1 , Llufriu, S. 1 , Saiz, A. 3 , Sanchez-Dalmau, B. 2 & Villoslada, P. 1
1 August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
2 Hospital Clinic of Barcelona, ICOF, Barcelona, Spain
3 Hospital Clinic of Barcelona, Neurology Department, Barcelona, Spain
Objectives: to assess the dynamics of retinal damage after acute optic neuritis (ON) by Optical Coherence Tomography (OCT) and to identify early OCT predictors of visual disability to improve the understanding and clinical management of axonal and neuronal degeneration in ON.
Methods: 31 patients with ON (idiopathic or Multiple Sclerosis related) were evaluated from clinical onset to month 6: retinal OCT (Spectralis) every month [thicknesses of peripapilar retinal nerve fiber layer (pRNFLTH) and macular layers)] and best-corrected high contrast, low contrast (LCVA) and color visual acuity (CVA), and visual field testing (VF) every 2 months.
Results: After 6 months, pRNFLTH decreased 39.6 ?m and macular
thickness 14.8 ?m. Most pRNFLTH decreased in first 2 months while macular thickness decreased along 3-6 months: thickness of inner macular layers [RNFLTH and ganglion cell layer + inner plexiform layer complex thickness (GCIPTH)] decreased monthly (specially in first 2 months), for outer layers increased in first 2 months, decreasing by months 3-6. GCIPTH change at first month predicted visual impairment at month 6: decrease >4.5 ?m (6.5%) poor LCVA, and > 7 ?m (10%) poor VF and CVA .
Conclusions: retrograde axonal degeneration and atrophy of ganglion cells develop within 3 months in ON, while outer layers suffer transient compensatory thickening. Atrophy of GCIP after 1 month of clinical onset is predictive of short-term visual disability.