"The Sooner the Better": How Long Will the Recovery of Vision Last in Traumatic Optic Neuropathy?

Abstract

Abstract: : Purpose: To report the 5–year outcome of patients affected by indirect traumatic optic neuropathy (TON) who presented an initial recovery after trauma. Methods: A cohort of 12 patients with partial/total recovery of vision and living in the Parma area was followed for an overall period of 5 years after conservative treatment for TON. Every 6 months each patient underwent a complete neuro–ophthalmological visit including best corrected visual acuity, IOP measurement, visual field testing with quantitative Goldmann perimetry, 30° fundus photograph, and pattern reversal Visual Evoked Potentials. For our purposes, the visual acuity and the visual field extension three months after trauma (baseline) were compared with the ones 5 years later. Comparison of the visual perceived area between baseline and 5–year visual field was made using the AutoCAD 2000 software program (Autodesk Inc., CA, USA). The Wilcoxon matched–pairs signed–ranks test was used to assess differences in visual acuity and in visual field extension. Analyses were performed using STATA Statistical Software. Results: All patients showed a stable visual function 5 years after optic nerve trauma. There was no difference in visual acuity levels (p = 0.65) nor visual field surface area between baseline and the last follow–up visit. Anyway, a significant improvement in visual field extension (p = 0.036) was observed after perimetry evaluation. Two cases were excluded form the study for unilateral glaucoma secondary to traumatic angle recession in one case, and for retinal detachment two years after optic nerve trauma in a second case. Conclusions: The cohort of patients herein examined clearly shows that any improvement of visual function experienced within three months after TON is maintained at least for 5 years. These findings may be used by physicians as important clinical informations for patients affected by TON. Furthermore, these data may be helpful to better quantify morbidity related to optic nerve trauma and its permanent sequelae.

Keywords: trauma • neuro-ophthalmology: optic nerve • neuro-ophthalmology: diagnosis