Vanderbilt researchers have developed a system for enhancing the imaging capabilities of optical coherence tomography (OCT), a tool commonly used to monitor and treat patients with retinal disease. The image resolution of OCT, however, is intrinsically limited. Ideally, a contrast agent could be used to highlight specific parts of the retina within the image, but dye alone is largely ineffective because of the way OCT generates the image. Photothermal heating solves this problem by creating local zones of tissue expansion which can be distinctly detected by OCT. Photothermal-OCT is safe, effective, and enhances the imaging power of a tool widely used by opticians.