Bilateral Ischemic Optic Neuropathy as the First Manifestation of Severe Anemia
Sayyeda Zahra1, Negar Moheb3, Christopher Melinosky2
1Neurology, 2Neurocritical Care, Lehigh Valley Health Network, 3Neuro-ophthalmology, Mayo Clinic
Background:
Anterior ischemic optic neuropathy (AION) is one of the leading etiologies for blindness or severe vision impairment. Acute lack of blood flow to the optic nerve head leads to irreversible ischemic injury. Small cup-to-disc ratio and common vascular risk factors are known to be associated with non-arteritic anterior ischemic optic neuropathy (NAION). Bilateral simultaneous NAION is extremely rare, and only a few cases of NAION secondary to severe anemia have been previously reported.
Results:
Case Report: A 52-year-old man with no known past medical history presented with generalized weakness and bilateral blurred vision progressing to no light perception within 2 days. Neuro-ophthalmologic exam revealed bilateral non-reactive pupils, diffuse 2+ disc edema, scattered flame and dot blot hemorrhages, and cotton wool spots. Brain magnetic resonance imaging (MRI) showed restricted diffusion of the bilateral optic nerve heads consistent with acute ischemia. He was found to have new onset severe macrocytic anemia with hemoglobin of 3.6g/dL, requiring multiple blood transfusions. Further workup was consistent with profound spur cell hemolytic anemia in the setting of newly diagnosed cirrhosis (Child Pugh C) leading to gastrointestinal bleeding. Inflammatory markers and the rest of infectious workup were unremarkable. Blindness was attributed to bilateral non-arteritic anterior ischemic optic neuropathy (NAION) due to severe anemia. Vision did not recover, and decompensated cirrhosis led to hepatorenal syndrome. Patient was ultimately transitioned to hospice care.
Conclusions:
Bilateral simultaneous NAION is rare. Our patient presented with bilateral NAION as the first manifestation of severe anemia secondary to undiagnosed cirrhosis. Severe anemia can lead to a reduction in the blood’s oxygen-carrying capacity causing ischemia. Furthermore, this case emphasizes the utility of diffusion-weighted MRI of the optic nerves to facilitate the diagnosis of AION.