It's an invisible illness, Baltimore County resident Jamie Shepard said. It's all inside, and so we put on a good front.Every six months, Shepard undergoes an eye exam at GBMC's eye center. Its just one of many appointments that have become part of his routine since being diagnosed with Lupus."One of my medications that I take could cause permanent eye damage and once that happens it cannot be reversed," Shepard said. "They do a special battery …