Confocal microscopy (CFM) is a diagnostic tool for cutaneous conditions that allows clinicians to visualize cellular details of the skin without the need for an invasive procedure. The microscope uses a laser to illuminate a small area of skin. Light is reflected back to the detector through a pinhole, which permits passage of light from the in-focus field only. With this input, a computer generates a two-dimensional grayscale image that corresponds to a transverse tissue section (ie. parallel to the skin surface). The contrast visualized by CFM is determined by the differential reflectance capability of various skin structures. The end result is a high-resolution image of the epidermis and superficial dermis that is obtained non-invasively and in real time.

The confocal microscope was first conceptualized by Marvin Minsky in 1957. As early as 1995, CFM was used in dermatology, as a tool used for clinical dermatology and in Moh’s research at the Wellman Laboratories of Photomedicine at Massachusetts General Hospital in Boston. By the early 2000’s, researchers from prestigious academic centers including Memorial Sloan-Kettering Cancer Center (New York, NY), Loma Linda University (Loma Linda, California), the Sydney Melanoma Unit (Sydney, Australia), University of Modena and Reggio Emilia (Modena, Italy), the Charite (Berlin, Germany) and University of Graz (Graz, Austria) were using CFM routinely, both as a research tool and a clinical diagnostic imaging device.

Today, confocal is widely used by dermatologists and researchers around the world to study and diagnose skin cancers, including melanoma, basal cell carcinoma and squamous cell carcinoma, along with a variety of other skin diseases, including psoriasis, actinic keratosis and seborrheic keratosis. Confocal microscopy has already had an impact on patient care and we imagine that this impact will continue and expand in the future.