Endoscopic treatment for a huge neonatal prepontine-suprasellar arachnoid cyst: a case report

A huge prepontine-suprasellar arachnoid cyst was identified by fetal sonography and magnetic resonance imaging. It was successfully treated with a two-stage operation using a neuroendoscope. The first operation during the neonatal period consisted of implantation of a cyst-peritoneal shunt. In the second operation, the cyst was fenestrated with the aid of a neuroendoscope. The cyst membrane was seen to cover the foramen magnum and to extend continuously to the ventral surface of the brain stem. At the foramen magnum, it was pulsating synchronously with the pulsation of the vertebral artery, which was suggestive of the mechanism of cyst growth. A ventriculo-peritoneal shunt was inserted to replace the cyst-peritoneal shunt. Endoscopic cyst fenestration is a less invasive alternative for the treatment of arachnoid cysts and can also be used for young children. In that case, however, special care should be taken to avoid complications, especially if the cyst exerts considerable pressure on the critical areas of the brain.