S9C8bP1b-3: The section is parallel to the surface of the skin; dermal papillae are cut in cross section. Yellow arrows identify the basement membrane zone (i.e., a boundary between the epidermis [zones with white birefringence] and the dermal papillae [cut in cross section]). The dermal papillae contain birefringent (red) collagen bundles cut in cross section. These are the fibrous “lamellae” as seen in the dermal papillae in S9C8aP1a-2).

S9C8bP1b-4: Myxedema may be associated with circulatory changes. In this field, the papillary dermis is markedly widened and mucinous. Mucinous changes are also evident in the reticular dermis (lower 1/4 of the field). Vessels are increased in number; they have thickened walls and are dilated. The vascular changes are a variation of patterns seen in acral angiodermatitis; the vessels are not arranged in lobular arrays. In combination, the changes are compatible with elephantiasic pretibial myxedema.