BACKGROUND
Reflectance Confocal Microscopy (RCM) is a new tool in the diagnosis and monitoring of skin disease. RCM uses an 830 nm laser to illuminate the skin and captures horizontal cross-sectional 8 mm X 8 mm mosaic images with high resolution. RCM has been used in the diagnosis of skin cancer and inflammatory skin diseases with good sensitivity and specificity,1,2 but the use of RCM to study wound healing is recently being explored.Traditionally, animal models have been used to study wound healing. Wound healing research in humans can pose several challenges, including difficulty in obtaining biopsy at the same location multiple times, and iatrogenic changes induced in the skin due to the act of performing biopsies. In comparison, the in vivo non-invasive nature of RCM allows clinicians to capture images of skin over time without patient discomfort due to repeated biopsies. RCM has been used to study wound healing after laser treatment, cryosurgery, burn wounds, and chronic wounds,3,6 but to our knowledge, it has never been used to describe wound healing after an acute surgical wound such as a shave excision. We present serial in vivo reflectance confocal microscopy characteristics of wound healing after shave excision of an atypical nevus over a 1-month period and discuss the role of RCM in monitoring wound healing over time.
MATERIALS AND METHODS
A patient presented to our clinic with a suspicious pigmented nevus approximately 2.5 mm X 6 mm in size that was described as “changing and growing” over the course of 3 months. This lesion was visualized under dermoscopy and RCM (Vivascope 1500, Caliber ID, Rochester, NY). On RCM, it was noted that this melanocytic nevus had moderate cellular atypia, therefore the decision was made to perform a shave excision. Serial images of the wound were taken using RCM before shave excision and at days 1, 7, 21, and 28 days after removal. Horizontal mosaic images were acquired and analyzed by an expert confocal reader. A timeline of epithelialization, cellular infiltrate, and connective tissue deposition was reported in conjunction with prevailing observations.
RESULTS
RCM of the wound on day 1 after removal shows a large black ovoid defect, as well as numerous small bright cells and linear fibrillary structures in the middle of the wound corresponding to the acute inflammatory phase of wound healing (Figure 1).RCM of the wound on day 7 shows an ovoid black defect in the skin surrounded by normal honeycomb pattern. Numerous bright cells and an irregular honeycomb pattern with focal polarization are present at the edges (Figure 2). RCM of the wound on day 21 shows a symmetrical ovoid area surrounded by an irregular honeycomb pattern. The dark circular defect has decreased in size, representing wound healing and re-epithelialization of the wound. The irregular honeycomb pattern of newly formed epidermis contains focal chronic inflammatory cells. Numerous dilated vessels are present, indicating the proliferative phase of wound healing (Figure 3). RCM of the wound on day 28 shows a well demarcated ovoid area with regular honeycomb pattern and minimal small bright cells, corresponding to resolving inflammation and the remodeling phase of wound healing (Figure 4).
