1. ^*The Skin Center, Suite 5, Queensland, Australia
2. ^§The Gold Coast Hospital, Queensland, Australia
3. ^‡Optiscan, Victoria, Australia
4. ^†Dermatology Service, Memorial Sloan-Kettering Cancer Center, New York, New York, USA

Correspondence: Peter Delaney, Optiscan, PO Box 1066, Mt Waverley MDC, Victoria, Australia, 3149. E-mail: peterd@optiscan.com

Received 11 October 2002; Revised 10 March 2003; Accepted 28 April 2003; Published online 25 September 2003.

Abstract

Fluorescence confocal scanning laser microscopy, using a miniaturized handheld scanner, was performed to visualize the microscopic architecture of normal human epidermis in vivo. Fluorescein sodium (20 L of 0.2% wt/vol) was administered via intradermal injection to normal skin on the volar forearm of 22 patients. The skin was imaged continuously from 1 to 15 min after injection. Fluorescein was excited at 488 nm and the fluorescent emission was detected at >505 nm. In each subject, a series of images was collected at increasing depth, from superficial stratum corneum to papillary dermis. Features observed in confocal images were compared to those seen in hematoxylin- and eosin-stained sections of skin. The confocal images demonstrated the architecture of superficial skin in the horizontal plane. There was a transition in keratinocyte size, shape, and morphology with progressive imaging into the deeper epidermal layers. Superficial dermis and microscopic capillaries with blood flow were easily observed. The morphologic patterns associated with the major cell types of the epidermis were consistent with those known from conventional histology. We report the ability of in vivo fluorescence point scanning laser confocal microscopy to produce real-time, high-resolution images of the microscopic architecture of normal human epidermis using a noninvasive imaging technology.