Many Americans assume tuberculosis is a disease of the past, but the reality is one-third of the world's population is infected with TB - an estimated 10 to 15 million people in the United States alone.Second Opinion explores this historic disease and what you need to know to protect yourself.

Medical research has helped us lead longer, healthier lives, but it has also sparked ethical concerns and contentious political debate. Through a Parkinson's Disease case, panelists explore the controversial world of clinical trials and debate the potential gains and pitfalls of science on the edge.

Many Americans think loss of vision is a normal part of aging. Think again. The number one cause of vision loss is actually a disease called macular degeneration. This episode describes the disease and how you may be able to prevent it from compromising your vision.