Variable pattern of visual recovery of Leber's hereditary optic neuropathy.

AIMS To investigate pattern of visual recovery of nine patients with Leber's hereditary optic neuropathy (LHON) and a mitochondrial DNA mutation at 11778. METHODS Recovery was judged significant when a gain of two lines or more in the Landolt ring chart, 10 dB or more improvement of the mean deviation of static perimetry, or improvement of critical flicker frequency (CFF) over 35 Hz was shown. RESULTS All three visual functions tested dramatically recovered in one patient. Two other patients exhibited isolated improvement of CFF or visual field, respectively. CONCLUSION Partial improvement of visual function may be more widespread than previously recognised in LHON patients with the 11778 mutation.