At the age of twenty-four, journalist Paula Kamen's life changed in an instant. While putting in her contact lenses, the left lens set off a chain reaction, igniting a constellation of nerves that radiated backwards from behind the surface of her eye. The pain was more piercing than with any other headache she had experienced. More than a decade later, she still has a headache-the exact same headache. From surgery to a battery of Botox injections...