case_images: PMC5735433_01
case_images: Preoperative magnetic resonance imaging. The T2-weighted sagittal image (left) shows a large hyperintense retroclival cystic mass extending into interpeduncular and suprasellar cisterns, causing compression and posterior displacement of brain stem. The T1-weighted postgadolinium sagittal image (middle) shows a nonenhancing mass. Diffusion weighted image (right) demonstrates a mass lesion in interpeduncular cistern without restricted pattern
case_images: SNI-8-289-g001.jpg
case_images: PMC5735433_01_SNI-8-289-g001.jpg
case_images: F1
case_images: Magnetic resonance imaging (MRI) revealed a prepontine arachnoid cyst extending into the interpeduncular and suprasellar cisterns along with brainstem compression [Figure 1].
case_images: Computed tomography scan demonstrates no evidence of hydrocephalus
case_images: SNI-8-289-g002.jpg
case_images: PMC5735433_01_SNI-8-289-g002.jpg
case_images: F2
case_images: No evidence of hydrocephalus on computed tomography (CT) scan was visible [Figure 2].
case_images: Intraoperative transnasal endoscopic view after fenestration of the cyst into adjacent cisterns
case_images: SNI-8-289-g003.jpg
case_images: PMC5735433_01_SNI-8-289-g003.jpg
case_images: F3
case_images: The cyst was opened into the prepontine, interpeduncular, and suprasellar cisterns [Figure 3].
case_images: Postoperative magnetic resonance imaging. The T2-weighted axial (left) and sagittal (right) images show cyst shrinkage and decompression of brain stem
case_images: SNI-8-289-g004.jpg
case_images: PMC5735433_01_SNI-8-289-g004.jpg
case_images: F4
case_images: Follow-up MRI showed a decrease in the size of the cyst and decompression of the adjacent tissues [Figure 4].