FIG 1. Images in a patient with a solid cerebellar tumor that progressed to enlarging cysts with the subsequent development of symptoms.

A, Contrast-enhanced T1-weighted MR image obtained at presentation demonstrates a 12-mm, enhancing, solid tumor in the right cerebellar hemisphere (arrow) (720/13 [TR/TE]).

B, Axial short-tau inversion recovery (STIR) image obtained 17 months later shows a large cyst associated with this solid tumor (arrow). An incidental left endolymphatic-sac tumor is also depicted on this image (arrowhead). (5660/29.7; TI, 150)

C, CT image shows further enlargement of the cyst 21 months after the initial study. The patient experienced posterior fossa symptoms at this time but declined surgical excision of this tumor, instead opting for craniotomy and cyst aspiration. (943/17)

D and E, MR images obtained 29 months after the initial examination. Contrast-enhanced axial T1-weighted image (D) (943/17) demonstrates enlargement of the solid part of the tumor (arrow). T2-weighted image (E) (4400/96) shows that the cyst has recurred, as had the patient’s symptoms. Surgical excision was performed shortly after this image was obtained.