Leber hereditary optic neuropathy. A 17-year-old experienced severe, painless vision loss in his left eye. A, Visual field testing demonstrated a central scotoma in the left eye. Two months later, the patient lost vision in the right eye. Mitochondrial genetic testing revealed the 11778 mutation. B, Fundus photographs demonstrate hyperemic optic discs with blurred margins and moderately tortuous vasculature. The left optic disc shows mild temporal pallor. C, There was no leakage on fluorescein angiographic studies