“What do you mean ‘You can’t see.’!?,” I asked. We were speeding north through Maryland on Interstate 81 heading to NJ for a family weekend. Mandy was a little quiet and, when I glanced over, I saw real fear on her face. In a slightly panicked voice, she said that for the past 15 minutes she had strange wavy lines coming in and out of her field of vision. They had started appearing towards the peripheral areas. Now those lines were obstructing everything and, in places, shutting out...