[Observation of the ventricular system and subarachnoid space in the skull base by flexible neuroendoscopy: normal structures].

Worldwide in the last two decades, in Latin America in the last decade, and Mexico in particular cerebral endoscopy as part of the minimally invasive neurological surgery, has constituted a significant advance for the treatment of neurological diseases such as congenital or acquired hydrocephalus, Chiari malformation, neurocysticercosis, stroke, ventricular and paraventricular tumors and cysts, arachnoidal cyst and hydrocephalus secondary to shunt malfunction. The lateral ventricles, the third ventricle, the cerebral aqueduct, the fourth ventricle, and the subarachnoid basal cisterns are among the most non-accessible regions of the central nervous system. Due to light-rand fiber optic-systems in combination with the experiences of nine consecutive year's and more than 600 endoscopies, most of them flexible neuroendoscopies, we present the neuroendoscopic approach with flexible cerebral endoscope to the anatomy and its normal variants of the whole ventricle system and the subarachnoid basal cisterns including the subarachnoid space of the cervical spine. We also describe their site related structures including veins, arteries, cranial nerves, pituitary gland, choroidal plexus and their normal anatomic variants.