What technology that you conceived of or developed has most surprised you, in term of its ultimate clinical impact?
I would say confocal microscopy. In the mid-1990s I worked with a physicist named Robert H. Webb, who invented an imaging system for the retina. We got together, noodled about it, and decided we would modify his ophthalmoscope system to see if we could get images from inside the skin. It worked pretty well. It was truly surprising from many points of view. First, it wasn’t clear at all that we’d get any images this way. Now, reflectance confocal microscopy is a standard tool in both clinical and research dermatology. But there were odd discoveries early on. For example, the darker your skin, the brighter it appeared in the microscope. You might think that melanin absorbs light and that you would get poor images in dark skin. It was the exact opposite; melanin acts as a natural contrast agent.
We worked with a small company to make the first confocal microscope. Initially, it had no clinical applications but what was fascinating to me was the incredible value of being able to see inside human skin harmlessly, and just see what’s going on. It became a potent research tool, and recently CPT codes were established for its use in evaluating skin cancer margins. I wouldn’t be surprised if 30 years from now, taking a skin biopsy is seemingly barbaric. A forerunner of all these new imaging tools for the skin was the confocal microscope developed in my lab in 1994.
During a 2011 TED talk, you said that nevus of Ota is your favorite thing to treat, because the outcome is usually perfect skin. Are there other technologies or devices you played a role in developing that make you proud at this stage in your career?
The reason I love treating nevus of Ota is that you have a lifelong facial disfigurement, and the only treatment for it is a laser we came up with, and it always works. How perfect could it be? The flip side of the same coin is, there are lesions of the skin that just don’t respond. One of the things we don’t know enough about is the connection between the biologic aspects of repair of various lesions and the treatments that we come up with. The most recent example of selective photothermolysis is a new laser we’re building right now for acne that is based on sebaceous gland injury. You’ll see this coming out in the next year or two. My heart goes out to people with nodular cystic acne. For young men it’s highly associated with suicide. So, I’m excited about optimizing and learning what happens when we target sebaceous glands.
One of the other big stories in laser dermatology is the fractional laser. I developed this with Dr. Dieter Manstein when he was a postdoc in my lab. One of the most pleasing things from this technology is how well you can rehabilitate scars, particularly burn scars in children. Over the last few years, I have trained plastic surgeons at the Shriners Hospital for Children in Boston on how to use fractional lasers to improve the lives of these kids. Another technology I developed with Dr. Manstein is cryolipolysis, which is removing fat from the body by cooling it. There are no lasers involved with this technology. I like to say that I’ve spent most of my career studying light and heat, and now we’ve come up with something that’s cold in the dark. We are now working on derivatives of cryolipolysis, to determine if what we’ve learned about targeting fat that might be applicable elsewhere.