Department of Radiology, Kangnam Sacred Heart Hospital, College of Medicine, Hallym University, Korea. ikyang@hallym.or.kr
Published online: September 1, 2011.
ABSTRACT
PURPOSE: We reviewed the sonographic features of Morel-Lavallee lesions by correlating the US image findings with a lesion's age. MATERIALS AND METHODS: We obtained the sonography reports of 20 Morel-Lavallee lesions of the hip and extremities from 18 patients with a history of trauma. The US images were reviewed to characterize the echogenicity, shape, homogeneity, margins, location and size of the lesions. The results were correlated with the age of the lesions and the clinical histories. RESULTS: All the Morel-Lavallee lesions were hypoechoic or anechoic fluid collections located between the subcutaneous fat and the underlying fascia. Regarding the shape of the fluid collections, the lobular shaped lesions were all less than 21 days for the lesion's age, and the flat fluid collections were all greater than 1 month of age. Regarding the homogeneity, the heterogeneous fluid collections were all less than 25 days of age, and the homogeneous fluid collections were all greater than 1 month of age. CONCLUSION: A Morel-Lavallee lesion is seen as a posttraumatic fluid collection in the potential space between the subcutaneous fat and the underlying fascia on an ultrasound examination. Acute Morel-Lavallee lesions tended to be heterogeneous and lobular, and they became more homogeneous and flat in shape as the lesions evolved. Awareness of these imaging findings will help us to properly diagnose Morel-Lavallee lesions.