'Gigapixel' camera can help diagnose skin cancer early

A high resolution 'gigapixel' camera capable of imaging the entire human body down to a freckle can help doctors spot deadly skin cancer early.
Developed by a team of researchers at Duke University in North Carolina the "gigapixel whole-body photographic camera" is essentially three dozen cameras in one.
"The camera is designed to find lesions potentially indicating skin cancers on patients at an earlier stage than current skin examination techniques," said Daniel Marks, one of the co-authors on the study.
"Normally a dermatologist examines either a small region of the skin at high resolution or a large region at low resolution, but a gigapixel image doesn't require a compromise between the two," Marks said.

Melanoma is the deadliest form of skin cancer, causing more than 75 per cent of skin-cancer deaths. If caught early enough, it is almost always curable.
Whole-body photography has already been used to identify melanomas and exclude non-dangerous "stable" lesions, but the approach is typically limited by the resolution of the cameras used.

A commercial camera with a wide-angle lens can easily capture an image of a person's entire body, but it lacks the resolution needed for a dermatologist to zoom in on one tiny spot.
So dermatologists typically examine suspicious lesions with digital dermatoscopy, a technique to evaluate the colours and microstructures of suspicious skins not visible to the naked eyes. The need for two types of images drives up costs and limits possibilities for telemedicine.

The gigapixel camera solves this problem by essentially combining 34 microcameras into one.
With a structure similar to a telescope and its eyepieces, the camera combines a precise but simple objective lens that produces an imperfect image with known irregularities.
The 34 microcameras are arranged in a "dome" to correct these aberrations and form a continuous image of the scene.
The exposure time and focus for each microcamera can be adjusted independently, and a computer can do a preliminary examination of the images to determine if any areas require future attention by the specialists.
Marks pointed out that although the resolution of the gigapixel camera is not as high as the best dermatoscope, it is significantly better than normal photography, and allows for a larger imaging area than a dermatoscope and could be used for telemedicine, which could make the routine screening available to a larger number of people, even in remote locations.

The research will be presented later this month at The Optical Society's (OSA) 98th Annual Meeting, Frontiers in Optics in Tucson, US.