72 years, Female, lung cancer with brain metastases. Evaluate response to chemotherapy. Status post whole brain radiation in June 2015. Within the right posterior parietal white matter there is an enhancing T1 isointense lesion measuring up to 1.0 cm (series 11, image 10), previously 1.8 x 0.6 cm. A right cerebellar enhancing lesion measures 0.7 x 0.5 cm (series 11, image 24), previously 1.1 x 0.8 cm. Additional foci of enhancement particularly within the left parietal lobe appear more conspicuous (series 11, image 10), while others are no longer visualized. There is a single new enhancing lesion within the left middle frontal gyrus measuring up to 4 mm (series 11, image 11). No restricted diffusion to suggest acute ischemia. There is no intracranial hemorrhage. The ventricles are within normal limits in size and configuration. Additional subcortical and periventricular T2 hyperintense foci do not enhance and are nonspecific, but most likely due to chronic microvascular ischemic disease, unchanged from prior.There is no abnormal parenchymal or meningeal enhancement. Major flow-voids are preservedSella and orbits are grossly within normal limits. Paranasal sinuses and mastoid cells are clear. Bone marrow signal and extracranial soft tissues are within normal limits.
Decreased size of largest brain metastases, with stability of additional smaller lesions. However, a single new enhancing focus within the left middle frontal gyrus is seen. Findings compatible with mixed treatment response.