Diffuse optical tomography is a way for doctors to look inside your body using light. Imagine you have a flashlight and you shine it on the wall. Some of the light bounces back to your eyes, and you can see the wall. Doctors do the same thing with your body. They shine light on the part of your body they want to look at and then measure how much light goes through and how much bounces back. This helps them make a picture of what's inside your body. They can use this picture to see if there are any problems, like an injury or a sickness. It doesn't hurt, and you don't need any needles or anything scary. It's like having a flashlight shine inside you to see what's going on.