[High resolution MR imaging of the skin: normal imaging features]. / IRM haute résolution de la peau: aspects normaux.

ABSTRACT

PURPOSE: To describe the qualitative and quantitative MR imaging features of normal skin. MATERIALS AND METHODS: Thirty-one normal subjects underwent MR evaluation on a 1.5 Tesla magnet using a dedicated coil. Several skin sites were evaluated (back at the scapular level, posterior calf and inferior heel). Two pulse sequences were acquired a SE T1W and a gradient-echo sequence (FIESTA). Qualitative and quantitative analysis was performed for all three sites. RESULTS: In normal subjects, the different skin layers (callus, epidermis, dermis, hypodermis and pilosebaceous follicles) can be separated and measured on MR. Epidermis and hypodermis are hyperintense whereas dermis is hypointense. Our results confirm the presence of qualitative and quantitative variations between different skin regions. In some cases, a differentiation between papillary and reticular dermis can be achieved. Pilosebaceous follicles and the deep vascular network were clearly depicted on the FIESTA sequence. Measurements for each skin layer were compared based on sex, site and MR pulse sequence. CONCLUSION: MRI provides evaluation of the different skin layers, epidermis, dermis, and hypodermis, and their different components.