case_images: PMC5292156_01
case_images: Axial noncontrast brain CT scan shows a hyperdense mass (arrow) at the location of interventricular foramen of Monro. Frontal and temporal horns of lateral ventricles are visible and enlarged.
case_images: CRINM2017-2978080.001.jpg
case_images: PMC5292156_01_CRINM2017-2978080.001.jpg
case_images: fig1
case_images: Computed tomography (CT) scan of the brain revealed enlargement of lateral ventricles and a well-circumscribed hyperdense mass on the roof of the third ventricle at the location of foramen of Monro (Figure 1).
case_images: Brain MRI. Axial FLAIR image (a) shows enlargement of lateral ventricles. The hyperintense rim around the ventricles represents interstitial edema secondary to acute hydrocephaly. Coronal T2-weighted image (b) reveals a round hypointense lesion at the location of interventricular foramen of Monro (arrow in (b)). The lesion (arrow in (c)) is isointense in the axial T1-weighted image (c). The size of the lesion is exaggerated in the b0 sequence of DWI image (d); a finding that suggests hemorrhage (arrow in (d)).
case_images: CRINM2017-2978080.002.jpg
case_images: PMC5292156_01_CRINM2017-2978080.002.jpg
case_images: fig2
case_images: On MRI examination, a hyperintense rim was seen around lateral ventricle on FLAIR sequence that was compatible with interstitial edema and acute nature of hydrocephaly (Figure 2(a)). T2-hypointese (Figure 2(b)), T1-isointense mass was seen on the roof of the third ventricle (Figure 2(c)). The characteristic location and MRI signal intensity were consistent with colloid cyst. Blooming artifact was visible on susceptibility weighted sequence (Figure 2(d)) and suggested the hemorrhagic nature of the lesion and explained the occurrence of acute hydrocephaly.