the affected side or sides. Hydrocephalus can be identified by a CT scan or MRI scan of the brain, and treatment involves a neurosurgical operation in which an endoscope (i.e., a tiny camera and tools) is used to widen the foramen or create a new opening through the septum pellucidum between the lateral ventricles. If an obstructing mass is too large or too difficult to remove endoscopically, an open operation or the insertion of an artificial path between the ventricles and peritoneum may be required. Because of the intimate nature of pathways within the brain, such operations may result in damage to nearby structures, with complications including anterograde amnesia, inability to move half the body, akinetic mutism and disconnection syndromes. History The foramina were named after the Scottish physician and University of Edinburgh graduate Alexander Monro, who first described an enlarged foramen in the context of hydrocephalus in a presentation to the Philosophical Society of Edinburgh in 1764, and subsequently in his 1783 publication, Observations on the Structure and Functions of the Nervous System. In this publication, Monro notes that the ventricular system has been noted to be connected, implying the presence of the foramen, since the time of the physician anatomist Galen. Monro described it as: Monro's original description, of two lateral ventricles joined by a foramen that then joined the third ventricle, is in fact incorrect. As noted by Monro himself, previous authors have also described the ventricles as having connections; consequently, the eponym of "Monro" has been disputed. References Books External links Ventricular system