Many surgeons rely on sight and touch to find cancerous tissue during surgery. Large hospitals or cancer treatment centers may also use experimental near-infrared fluorescent agents that bind to tumors so surgeons can see them on specialized displays. These machines are costly, making them difficult for smaller hospitals to procure. They also are very large, making them difficult to fit into an operating suite and integrate smoothly into surgery, and they require the lights to be dimmed so the instruments can pick up the weak fluorescent signal, making it difficult for the surgeons to see.
Researchers have developed a surgical camera inspired by the eye of the morpho butterfly. The camera, connected to goggles worn by the surgeon, sees infrared signals given off by tumor-binding dyes so the surgeon can remove all of the cancerous tissue.
The morpho butterfly’s eye has specialized nanostructures that allow it to see multispectral images including near-infrared. The camera was built with the same kinds of nanostructures, creating a small camera that can simultaneously register regular color images and near-infrared signals without needing to dim the room lights. The goggles protect the surgeon’s eyes and also project the fluorescent information.
The camera was used to find sentinel lymph nodes in human patients with breast cancer. Surgeons used a common green dye that also happens to emit an infrared signal. The researchers compared how well the physicians could identify the lymph nodes in a patient with breast cancer by looking for green color by eye, and then looking for the infrared signal using the butterfly-eye camera. Sometimes when looking for green coloration, the surgeon must look for a while since the nodes are below the surface. With the fluorescence, the surgeon can see through the skin or the tissue and identify the nodes much quicker.