LOCALIZATION OF DERMAL EDEMA IN LIPODERMATOSCLEROSIS, LYMPHEDEMA, ANDCARDIAC-INSUFFICIENCY - HIGH-FREQUENCY ULTRASOUND EXAMINATION OF INTRADERMAL ECHOGENICITY

Background: Chronic edema in venous insufficiency is associated with l eg ulceration, whereas in lymphedema skin ulceration is less frequent and edema from cardiac failure does not cause major skin changes. The reason for these differences is unclear. Objective: Our purpose was to investigate, by means of ultrasound, the distribution of intradermal fluid in patients with edema associated with Lipodermatosclerosis, lym phedema, or cardiac insufficiency. Methods: Sixteen patients with lipo dermatosclerosis, 10 with lymphedema, 16 with leg edema from heart ins ufficiency, and 16 healthy control subjects were studied. Ultrasound i mages were obtained with a 20 MHz scanner. The echogenicity of the der mis was quantified by image analysis and the echogenicity of the upper (subepidermal) and lower portions of the dermis were measured. Result s: In any type of edema the dermal echogenicity was lower than that of the control group, indicating intradermal edema. In normal skin the u pper dermis was Only slightly less echogenic than the lower dermis. In patients with lipodermatosclerosis a low-echogenic area was present i n the upper dermis, which suggests the papillary dermis as a preferent ial site of edema formation, In contrast, in lymphedema dermal echogen icity was uniformly distributed, whereas in patients with heart failur e the lower portion of the dermis was less echogenic than the upper de rmis. Conclusion: This study demonstrates that intradermal echogenicit y shows characteristic patterns in different types of edema, which ind icates that localization of fluid varies in the dermis, from subepider mal (lipodermatosclerosis), uniform (lymphedema), to deep dermal (hear t failure), These differences may help in understanding the origin of different skin sequelae of edema.