TY - CHAP M1 - Book, Section TI - The Vascular Purpuras A1 - Lichtman, Marshall A. A1 - Kaushansky, Kenneth A1 - Prchal, Josef T. A1 - Levi, Marcel M. A1 - Burns, Linda J. A1 - Armitage, James O. PY - 2017 T2 - Williams Manual of Hematology, 9e AB - Purpura is the extravasation of red cells from vasculature into the skin and/or subcutaneous tissues.Petechiae are red-purple lesions less than 2 mm in diameter.Purpura describes red-purple lesions 2 mm to 1 cm.Ecchymoses are red-purple lesions greater than 1 cm.Erythema is reddened skin due to increased capillary flow.Telangiectasia is dilated superficial capillaries.Erythema and telangiectasia blanch with pressure, and petechiae and purpura do not. This can be easily demonstrable with a glass microscope slide. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/19 UR - hemonc.mhmedical.com/content.aspx?aid=1133365940 ER -