Fig. 4

a–d. The different performances of orbital LCH lesions in T2WI:Axial (a) T2-weighted MR images show lesion located in the inferolateral right orbit with a clear border, and presenting hypointensity in a T2-weighted image with a low signal ring of the lesion edge;and coronal (b) T2-weighted MR images show lesion located in the right superolateral orbit with an irregular shape like a triangle and an unclear boundary, presenting hyper-hypointense mixed signals; Axial (c) T2WI show lesion located in the lateral wall of the left orbit presenting slightly hyperintense signals with a clear boundary. Axial (d) T2WI show lesion located in the superior wall of the right orbit presenting multiple cystic hyperintense signals near the edge of the lesion