Background: Lipodermatosclerosis is a sequela of deep venous insufficiency and a risk factor for the occurrence of venous leg ulceration. Medical compression stockings facilitate leg ulcer healing and prevent occurrence of ulcers resulting from removal of edema. Although the exact level of compression necessary for removal of dermal edema in patients with deep venous insufficiency has not been established, garments providing high compressive values of 30 to 40 mm Hg have been recommended. Dermal edema can be visualized by high-frequency ultrasonography. Objective: We used ultrasound imaging to study whether a lower level of compression (class I 18 to 26 mm Hg vs class II 26 to 36 mm Hg) is effective in removal of dermal edema. This question is important because the use of hosiery with a lower compression class would enhance compliance and enable treatment of patients with mixed arteriovenous disease. Methods: In 11 patients skin images were obtained with 20 MHz ultrasound from the malleolar region in lipodermatosclerotic skin and corresponding normal skin of the contralateral leg. The ratio of low echogenic pixel number to total pixel number (LEP/TP), which correlates with dermal water, was measured before and after 5 days of applied compression in two treatment courses where classes of compression were switched randomly. Ankle circumference was also measured. Results: We found that LEP/TP was 33% higher in lipodermatosclerotic skin than in the matched normal skin indicating presence of skin edema. Application of class I and II compressive hosiery resulted in LEP/TP decrease by 17% (95% confidence interval, 0.07 to 0.26) and 14% (95% confidence interval, 0.04 to 0.21), respectively, suggestive of dermal edema reduction. No statistically significant difference in efficacy of dermal edema removal between class I and II was found. No changes in ankle circumference after application of both classes of compression was observed. Conclusion: Application of light and moderate compression results in a partial edema removal from the dermis in lipodermatosclerosis in the absence of measurable reduction in leg circumference. Class I compression is as effective as class II for elimination of dermal edema. These data indicate that light compression may be a useful modality for patients with deep venous insufficiency and lipodermatosclerosis who are not eligible for treatment with garments having higher compressive forces. (J Am Acad Dermatol 1998;39:966-70.)