35-year-old male with a history of metastatic rectal cancer with cerebellar metastases presents with a headache. Again seen are multiple, well-circumscribed, contrast-enhancing lesions involving the bilateral cerebellar hemispheres and the cerebellar vermis. The ring-enhancing lesion in the right cerebellar hemisphere measures 35 x 29 mm (series 6, image 43). The ring-enhancing lesion in the left cerebellar hemisphere measures 24 x 24 mm (series 6, image 67). The ring-enhancing lesion in the cerebellar vermis measures 20 x 18 mm (series 6, image 59). Overall, the lesions have not significantly changed since the prior outside hospital study, but have increased since the study from 10/5/2015. A fourth lesion at the junction of the cerebellar vermis and right cerebellar hemisphere (series 6, image 60) has increased in size from the prior outside study. No definite new enhancing or supratentorial lesions are identified.There is no evidence of acute intracranial hemorrhage or acute infarct. The sulci and ventricles are mildly prominent indicating volume loss, perhaps slightly progressed. There are scattered periventricular and subcortical T2 hyperintense white matter foci which are much more conspicuous compared to the prior examination. There is mild mass effect on the fourth ventricle. The skull, paranasal sinuses, and scalp soft tissues are grossly unremarkable. There is a new, abnormal T1+C hyperintense, T2 hypointense lobulated soft tissue thickening in the left globe which appears mass-like in certain planes.
1. Multiple metastatic lesions in the posterior fossa are stable to slightly increased in size compared to the prior OSH study. No definite evidence of any new lesions. 2. No evidence of acute intracranial hemorrhage or hydrocephalus.3. New lobular soft tissue thickening in the left globe correlates with patient's known history of left retinal detachment, however, an underlying metastatic lesion cannot entirely be excluded.4. Scattered periventricular and subcortical T2 hyperintense white matter foci which appear much more conspicuous compared to the prior examination. Differential consideration includes vascular and demyelinating disorders. 