Transient Homonymous Superior Quadrantanopsia in Nonketotic Hyperglycemia: A Case Report and Systematic Review

Nonketotic hyperglycemia often causes transient visual field defects, but only scattered anecdotes are available in the literature.

We report a patient with homonymous superior quadrantanopsia due to nonketotic hyperglycemia and provide a systematic literature review of the clinical features of 40 previously reported patients (41 in total, including our case) with homonymous visual field defects in association with nonketotic hyperglycemia.

The typical visual field defect was congruous (84.6%), homonymous hemianopsia (87.8%) with macular splitting (61.5%) or sparing (38.5%). It was transient and repetitive in 54.5% of the patients, but it developed as a persistent form in the remainder. Positive visual symptoms such as hallucinations and phosphenes developed in 73.2% of patients. Brain MRI revealed corresponding abnormalities in most patients (84.8%), characterized by a low-intensity white-matter signal or a high-intensity gray-matter signal on T2-weighted or fluid-attenuated inversion recovery images with diffusion restriction or gadolinium enhancement. Most (97.0%) patients recovered completely, with 48.5% treated by glycemic control alone and the remainder also receiving antiepileptic agents.

Nonketotic hyperglycemia should be considered a possible cause of transient visual field defects, especially when it is associated with repetitive positive visual symptoms and typical MRI findings in hyperglycemic patients.