Sight test finds mum's brain bug.
Rebekah Perrett, 24, thought faulty glasses were causing her headaches but her eye doctor noticed a swollen optic disc.
She was diagnosed with rare idiopathic intracranial hypertension - fluid pressuring the brain - that affects just one in 100,000.
Rebekah, who lives in Cheltenham, Glos, with husband Richard, 31, and five-month-old son Owen, had a lumbar puncture to ease the pressure.
She said: "It could have caused blindness, but it is so little known about that my GP had to Google it.
"It's incurable, so I will always have it. But you have to cope with these things."