High-frequency skin ultrasonographic and dermoscopic features of seborrheic keratosis

Abstract

Objective To describe high-frequency skin ultrasonographic and dermoscopic features of seborrheic keratosis (SK) . Methods Between August and December in 2017, 46 outpatients with SK were enrolled from the Department of Dermatology of Peking Union Medical College Hospital, and 50 SK lesions were observed by 50-and 20-MHz high-frequency skin ultrasonography and dermoscopy. The high-frequency ultrasonographic and dermoscopic features of SK lesions were summarized and analyzed. Statistical analysis was done by using chi-square test for comparisons of evaluation results of SK lesions between 50-and 20-MHz ultrasonography, and the correspondence between high-frequency skin ultrasonographic and dermoscopic features of SK was analyzed by calculating the simple matching coefficient. Results As 50-and 20-MHz ultrasonography showed, ultrasonographic features of SK lesions from top to bottom were enhanced hyperecho (48/50 vs. 39/50, respectively, P= 0.007) , enhanced hyperechoic masses or spots in the stratum corneum (22/50 vs. 11/50, respectively, P= 0.019) , sound shadows behind the epidermis (34/50 vs. 13/50, respectively, P 3) under dermoscopy were 58% (29) and 48% (24) respectively. Conclusion High-frequency skin ultrasonography and dermoscopy both are of great value to the assessment of SK lesions, and 50-MHz ultrasonography is superior to 20-MHz ultrasonography for imaging skin lesions. Key words: Keratosis, seborrheic; Ultrasonography; Dermoscopy; Pathologic processes; Skin manifestations