case_images: PMC6744798_01
case_images: (a and b) Computed tomography brain w/o contrast noting lobulated soft tissue density mass left lateral ventricle measuring 2.0 cm x 2.2 cm causing severe obstructive hydrocephalus at the foramen of Monroe.
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case_images: F1
case_images: Non-contrast brain computed tomography (CT) demonstrated a left lateral ventricle lobulated soft tissue density mass measuring 2.0 cm x 2.2 cm causing moderate-to-severe obstructive hydrocephalus at the foramen of Monroe [Figure 1a and 1b].
case_images: Magnetic resonance imaging brain with gadolinium demonstrating a large benign appearing mass causing obstruction of the left foramen of Monroe, (a) TI hypointense mass, (b) T2 hypointense mass, (c) Flair hyperintense mass with transependymal edema, (d) Axial T1 w/gad hypointense mass without evidence of enhancement, (e) Sagittal T1 w/gad non-enhancing mass obstructing foramen of Monroe, (f) Coronal T1 w/gad non-enhancing mass obstructing lateral ventricle with left ventricle hypertrophy and rightward septal shift.
case_images: SNI-10-95-g002.jpg
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case_images: F2
case_images: Subsequent magnetic resonance imaging (MRI) illustrated a large benign appearing mass obstructing the left foramen of Monroe [Figure 2a-f].
case_images: 2" incision incorporating the ventriculostomy puncture site.
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case_images: F3
case_images: A two-inch straight incision was made over the left frontal region incorporating the ventriculostomy puncture site [Figure 3].
case_images: 14 mm x 6 cm minimally invasive spinal tubular retractor used for the transcortical exposure of the mass in the left lateral ventricle.
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case_images: F4
case_images: Minimally invasive spine sequential dilators followed this trajectory to the ventricle to place a 14-mm diameter by 6-cm length minimally invasive spinal tubular retractor [Figure 4].
case_images: Ventricular anatomy, labeled.
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case_images: F5
case_images: The ventricular anatomy was examined to confirm open CSF pathway before removal of the tubular retractor [Figure 5].
case_images: Postoperative magnetic resonance imaging brain w/gad demonstrating total resection of the mass and decreasing lateral ventricle hydrocephalus with minimal cortical disturbance, (a) Axial T1 w/gad with decreased left lateral ventricular hydrocephalus and gross total resection of ventricular mass, (b) Flair demonstrating reduced transependymal edema, (c) Sagittal T1 w/gad with gadolinium with patent foramen of Monroe after complete resection of intraventricular mass, (d) Coronal T1 w/gad illustrating the trajectory of tubular channel through cortex, (e) Sagittal T1 w/gad view of tubular channel through the cortex, (f) Axial flair view minimal cortical disruption.
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case_images: F6
case_images: Follow-up MRI demonstrated gross total resection of the mass and decreased lateral ventricle hydrocephalus with minimal cortical disturbance [Figure 6a-f].
case_images: (a-c) Subependymoma with microcystic degeneration, the WHO Grade 1, (d and e) Positive lesional cell GFAP and S-100 immunostains, (f) Proliferating cell KI-67 immunostain fraction <1%.
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case_images: PMC6744798_01_SNI-10-95-g007.jpg
case_images: F7
case_images: Pathology demonstrated a subependymoma with microcystic degeneration, the WHO Grade 1 [Figure 7a-c]. Immunostains indicated that the lesional cells were positive for GFAP and S-100 [Figure 7d and 7e). The proliferating cell fraction was <1% on KI-67 immunostain [Figure 7f]. 2 weeks later, the patient had improvement in gait and resolution of tremor.