Figure 4: Non-Hodgkin B-cell lymphoma: (a) Axial scan of CT orbit showing diffuse medial rectus muscle enlargement*, (b) Coronal scan of CT orbit showing medial rectus muscle enlargement*, (c) A muscle biopsy from the medial rectus muscle stained with hematoxylin and eosin showing infiltration by malignant cells of non-Hodgkin lymphoma, (d) Strongly positive CD20 immunohistochemical staining. CT = Computed tomography