case_images: PMC6213805_01
case_images: Axial T1-weighted contrast-enhanced magnetic resonance image demonstrating a right temporoparietal, partial ring-enhancing lesion in the white matter
case_images: SNI-9-208-g001.jpg
case_images: PMC6213805_01_SNI-9-208-g001.jpg
case_images: F1
case_images: She had been treated with intravenous (IV) steroids and glatiramer acetate with excellent results in the past for episodes of left-sided weakness after MR imaging of the brain done 1 year before this presentation revealed a deep white matter lesion with an incomplete ring-enhancing pattern without midline shift or edema [Figure 1].
case_images: Axial computed tomographic image obtained at the time of admission, before high-dose steroid therapy was started, showing subfalcine herniation
case_images: SNI-9-208-g002.jpg
case_images: PMC6213805_01_SNI-9-208-g002.jpg
case_images: F2
case_images: A computed tomographic (CT) scan of the head demonstrated subfalcine herniation [Figure 2] secondary to extensive vasogenic edema, which explained her obtundation.
case_images: Axial computed tomographic image showing aggressive development of edema causing transtentorial herniation
case_images: SNI-9-208-g003.jpg
case_images: PMC6213805_01_SNI-9-208-g003.jpg
case_images: F3
case_images: A repeat CT scan revealed worsening edema, causing transtentorial herniation [Figure 3].