Abstract
Purpose: :
to study differentiating optical coherence tomography (OCT) findings that help distinguish a chronic retinal arterial occlusive disease (RAO) from chronic optic neuropathy
Methods: :
A retrospective observational comparative study included 20 eyes of 19 patients with permanent RAO and 32 eyes of 29 patients with chronic optic neuropathy whose assessment included macular OCT. The macular OCT changes in chronic central (CRAO) and branch (BRAO) retinal artery occlusion were compared to those in eyes with chronic optic neuropathy in an effort to establish differentiating features.
Results: :
Three main features differentiating chronic RAO from chronic optic neuropathy were identified on macular OCT testing. Complete inner retinal atrophy with loss of the normal stratification of the inner retinal layers, loss of the normal foveal depression, and marked thinning of the involved retina were found to be characteristic findings of chronic RAO, and were absent even in the most severe cases of chronic optic neuropathy. The involved retina was significantly thinner in chronic RAO compared to that in chronic optic neuropathy (p<0.05). These OCT features helped establish the diagnosis of chronic RAO in four cases referred with the misdiagnosis of optic neuropathy.
Conclusions: :
OCT findings in chronic RAO are characteristic. The extent and pattern of inner retinal atrophy differentiate a chronic retinopathy from an optic neuropathy and help guide the systemic workup. Moreover, they help establish the diagnosis of RAO in a subgroup of cases with chronic unexplained vision loss misdiagnosed as optic neuropathy.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • neuro-ophthalmology: diagnosis