Abstract
Introduction::
OCT is rapidly finding its way into analysis of progressive optic neuropathies (glaucoma) that cause nerve fiber layer loss. Recent studies have demonstrated that acute disc edema is associated with nerve fiber layer thickening. In patients with anterior ischemic optic neuropathy the thickness of nerve fiber layer often depends on the duration of the event.Materials &
Methods::
A total of 24 eyes in 21 patients with anterior ischemic optic neuropathy were evaluated with OCT. This was done in a retrospective fashion correlating visual field defects with OCT plus looking at thickness dependent on duration following the acute event.
Results::
Acute anterior ischemic optic neuropathy was associated with marked but variable nerve fiber layer thickening. The thickening tended to correlate with the area of disc seen to be swollen. Patients with anterior ischemic optic neuropathy of greater than 3 months duration tended have significant nerve fiber bundle dropout again corresponding to the areas of visual field defect. In the period between 2 weeks and 12 weeks there was variability of nerve fiber layer thickness.
Conclusions::
Nerve fiber layer thickness varies with anterior ischemic optic neuropathy. Acutely there is marked nerve fiber layer thickening and one cannot correlate this directly with visual function. Late follow up of anterior ischemic optic neuropathy shows nerve fiber layer loss which better correlates with final visual field defects.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • neuro-ophthalmology: optic nerve • nerve fiber layer