Natalie Adler: The Woman Who Turns Blind 3 Days a Week

Open and shut case: Natalie Adler tries to cram as much as she can into her open eye days, which are marked in her diary months ahead

Melbourne: An Australian woman becomes blind for three days a week when her eyes clamp shut voluntarily for the period and she can't open them, a baffling medical condition according to experts.

Natalie Adler (21), who doctors believe may be the only person in the world with this condition, has been living with the extraordinary visual impairment for four years.

"My eyes are closed for three days and then open for three days," said Adler. "I go to bed and I can open my eyes, and then when I wake up the next day I can't," she explained adding, "Nobody knows why."

During 'closed eye days' her eyes are completely shut, except for a small slit in her left eye. On 'open eye days' they function normally, although the left eyelid sometimes droops. Adler tries to cram as much as she can into those good days, which are marked in her diary months ahead. "On my 18th birthday my eyes were closed but on my 21st they were open, so I had a party," she said.