Figure 6a. Unilateral retinoblastoma in 20-month-old girl. (a) Transverse T1-weighted MR image (575/15) of right eye obtained after gadolinium-based contrast agent administration shows large tumor mass with inhomogeneous enhancement. Tumor invasion of the ciliary body (arrows) was suspected but was a false-positive finding, probably because of insufficient spatial resolution. The iris manifests as a hyperintense band anterior to the lens as a result of rubeosis iridis detected with ophthalmoscopic examination. (b) Histopathologic specimen shows a detail of the ciliary body (CB) (arrows) without tumor infiltration. Tumor (R) is adjacent to the ciliary body, anterior chamber, and iris (I). (Hematoxylin-eosin stain; original magnification, x10 objective.)