Lymphoma in the right orbit. (a) Axial unenhanced CT with a soft tissue algorithm shows an irregular soft tissue mass in the upper quadrant of the right orbit (long black arrow) adjacent to orbit wall with intraconal and extraconal space involved. The lesion extend anteriorly with medial angle and nasal dorsum involved (short black arrow). (b) Sagittal unenhanced CT with a soft tissue algorithm shows the lesion extending into the orbital apex region in an anterior-posterior pattern adjacent orbit wall with levator palpabrae muscle and superior rectus involved and eyeball encased partially. (c) Axial T1-weighted MR image shows the thickening levator palpabrae muscle and superior rectus with isointense signal. The lesion encased the eyeball partially and involved the medical angle (short white arrow) with adjacent skin thickened. (d) Axial T2-weighted MR image shows the lesion isointense and ill-defined. (e) Axial contrast-enhanced MR image with fat saturation shows the lesion with moderate homogenous enhancement (long white arrow). The eyeball wall is thickened and enhances significantly. The lesion in the medical angle shows heterogeneous enhancement. (f) Sagittal contrast-enhanced MR image shows the mass with moderate homogenous enhancement