Abstract: A 50-year-old man without a significant medical history developed progressive double vision from a partial right third nerve palsy, as well as right-sided hyperreflexia and decreased temperature sensation in his right hand. Initial contrast MRI of the brain revealed enhancement of the right oculomotor nerve. Cerebrospinal fluid and serologic studies were negative or normal. Over the next 6 weeks, he developed a left sixth nerve palsy and right-sided facial sensory changes, followed by a partial left third nerve palsy and right foot drop. The patient later disclosed a 2-year history of painful right hemiscrotum swelling. Abdominal imaging and testicular biopsy revealed a Stage IIA testicular seminoma and was treated with radical orchiectomy, steroids, intravenous immunoglobulin, and chemotherapy. He continued to deteriorate, with evidence of myelitis on thoracic MRI. Initial paraneoplastic studies were negative, and research-based antibody testing revealed leucine zipper 4 autoantibody positivity, indicating a paraneoplastic syndrome.
Background: Nonarteritic anterior ischemic optic neuropathy (NAION) and central retinal artery occlusion (CRAO) are both causes of acute vision loss. When patients present within the first several weeks of symptom onset, clinical signs such as optic disc or inner retinal edema often allow differentiation. However, as time progresses and edema resolves, both diseases lead to optic atrophy and retinal thinning, sometimes making them difficult to distinguish. Clinical experience suggests that CRAO results in more significant thinning of the inner retinal layers, particularly the ganglion cell layer (GCL), compared with NAION. This study seeks to investigate whether these differences remain detectable months after symptom onset and whether optical coherence tomography (OCT) imaging can reliably distinguish these entities in the chronic phase. Methods: This is a retrospective single-center cohort study comparing OCT-derived ganglion cell thickness, total retinal thickness, and asymmetry of inferior/superior hemiretinas in patients with NAION and CRAO who presented early after vision loss and underwent follow-up imaging at approximately 3, 6, or 12 months. Results: At all time points, GCL and retina thinning were more severe in the CRAO group. The ratio of GCL to total retina was significantly lower in the CRAO group. More asymmetry was observed in the NAION group, with the superior hemiretina more frequently affected. Conclusions: OCT average GCL thickness determined by automatic segmentation is an excellent discriminator between prior CRAO and prior NAION eyes at 3, 6, and 12 months.
