Hyperglycemic hemianopia: A case report

BACKGROUND: Nonketotic hyperglycemia (NKH) is characterized by hyperglycemia with little or no ketoacidosis. Diverse neurological symptoms have been described in NKH patients, including choreoathetosis, hemiballismus, seizures, and coma in severe cases. Homonymous hemianopia, with or without occipital seizures, caused by hyperglycemia is less readily recognized. CASE SUMMARY: We describe a 54-year-old man with NKH, who reported seeing round, colored flickering lights with right homonymous hemianopia. Cranial magnetic resonance imaging demonstrated abnormalities in the left occipital lobe, with decreased T2 signal of the white matter, restricted diffusion, and corresponding low signal intensity in the apparent diffusion coefficient map. He responded to rehydration and a low-dose insulin regimen, with improvements of his visual field defect. CONCLUSION: Patients with NKH may present focal neurologic signs. Hyperglycemia should be taken into consideration when making an etiologic diagnosis of homonymous hemianopia.