Effect of Multiradiance Low-Level Laser Therapy and Topical Silver Sulfadiazine on Healing Characteristics of Dermal Wounds in Marine Toads (Rhinella marina)

Figure 2

Gross and corresponding histologic images showing the healing progression of surgically induced 6 mm diameter fill-thickness dermal wounds in marine toads (Rhinella marina) in the control group at day 4 (a, b), day 7 (c, d), day 13 (e, f), day 19 (g, h), and day 28 (i, j). Histologic sections were stained with hematoxylin and eosin. The scale bar represents 200 micrometers. 2b: there is a thin layer of new epithelial growth (thin double arrows) that extends from the edge of the ulcer (arrowhead). There is a mild, predominately lymphocytic infiltrate, scattered within the tissue below the area of ulceration (arrow). 2d: the area of ulceration is completely covered by new epithelial growth (arrow) which is disorganized and easily separated from the underlying dermis (star) compared to the adjacent skin (arrowhead). A mild lymphocytic infiltrate and small amount of granulation tissue are present within the underlying dermis. 2f: the epithelium covering the previous area of ulceration (arrow) is disorganized and thickened (up to four times the adjacent epidermis (arrowhead)). Granulation tissue and early fibrosis are evident within the underlying dermis which also contains a moderate, diffuse, lymphocytic infiltrate. 2h: similar to 13 days, the new epithelium (arrow) is thicker and disorganized compared to the adjacent dermis (arrowhead). There is moderate fibrosis within the underlying dermis with prominent contracture of the wound resulting in projection of the affected region. 2j: the new epithelium is returning to normal thickness and organization (arrow) relative to the adjacent skin (arrowhead) and the dermal contraction is markedly reduced compared to day 19. Lymphocytes still diffusely infiltrate the dermis and form aggregates along the margin along with rare multinucleated giant cells (thick short arrows). Melanocytes are present within the superficial dermis of the previously ulcerated area; however, no adnexal structures are observed.

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