47 years, Female, follow-up post surgery and SRS for brain metastasis. Examination is motion degraded despite repeating multiple sequences. Compared to 4/6/2016, there has been evolution of postsurgical changes related to recent resection of left cerebellar lesion. Again seen is a heterogeneously enhancing tissue surrounding the resection cavity which appears stable to minimally more prominent, with more prominent interval increase in fluid filling the resection cavity which extends to the cerebellar surface. Extent of T2 hyperintensity related to vasogenic edema in the left cerebellar hemisphere extending into the left middle cerebellar peduncle and left dorsolateral pons is not significantly changed. Mass effect including mild effacement of the fourth ventricle is also not significantly changed. Partial effacement of the left ambient cistern is also similar to prior. No midline shift. No hydrocephalus. No uncal herniation.There has been slight enlargement of the enhancing right parietal lesion which measures 16 x 19 x 16 mm, previously 13 x 13 x 13 mm. There is surrounding vasogenic edema which is also slightly increased in the interval. Again noted is herniation of the left posterior aspect of the left cerebellar hemisphere at the previous craniotomy defect.There is a 7 x 7 mm enhancing right cerebellar lesion which has not been well seen on recent studies but demonstrates enlargement, measuring 5 x 5 mm on MRI dated 4/3/2016. There is a fluid collection involving the suboccipital soft tissues measuring approximately 2.6 x 5.8 cm in the axial plane which demonstrates increased peripheral enhancement, while the overall size of collection is similar to prior. Bilateral staphylomas are again noted.
1. There is been interval evolution of postsurgical changes related to resection of recent left cerebellar mass. Again noted are areas of irregular peripheral enhancement in the resection bed which remain suspicious for residual tumor although there is likely a component of radiation necrosis. Although the amount of this enhancing tissue is not increased, there is increased fluid within the surgical cavity and along the surgical tract which may reflect evolving postsurgical changes, but would suggest continued close follow-up evaluation.2. Enhancing right parietal and right cerebellar lesions demonstrate slight interval enlargement compared to 4/6/2016 and more prominent increase in size when compared to prior study from 3/3/2016. There is also mild increase in vasogenic edema surrounding the right parietal lesion. No new lesions are appreciated within the limits of motion degraded study.3. Fluid collection in the left suboccipital soft tissues is grossly similar in size to prior and compatible with a pseudomeningocele. There is increase in surrounding enhancement which may represent evolution of postsurgical change/granulation tissue. Superimposed infection however cannot be excluded.