Female, 59 years old, with metastatic lung adenocarcinoma to the brain, cerebellar mass, history of herniation, altered mental status. Greater than 20 solid and rim-enhancing lesions are evident within the brain and cerebellum. These lesions range in size from punctate up to 2.5 cm in diameter with the largest lesion present in the left cerebellum. The lesions are peripheral and in most cases associated with a sulcus. Along with potential enhancement of the left cisternal trigeminal nerve, this distribution would suggest that at least some of the lesions represent leptomeningeal involvement. Several of the larger lesions demonstrate susceptibility effect and or T1 hyperintensity suggesting trace blood product.Lesions in the bilateral frontal lobes and in the cerebellar hemispheres induce moderate local edema. However, no significant generalized mass effect or brain herniation is seen. The ventricular system remains within normal limits for size and morphology. Scattered T2 hyperintense foci without correlating enhancement are nonspecific but may reflect chronic microvascular ischemia. An enhancing focus is evident within the left aspect of the clivus potentially representing an osseous metastasis.
Greater than 20 intracranial lesions are demonstrated compatible with metastases. The distribution of the lesions, along with enhancement of the left cisternal trigeminal nerve, suggesting that at least some of these lesions are leptomeningeal in nature. Moderate local edema is seen in association with larger lesions in the bilateral frontal lobes and the bilateral cerebellar hemispheres. However, no significant generalized mass effect or brain herniation is seen. One osseous metastasis is suspected in the clivus.