New light on the technique and indications for ventriculo-cisternal drainage according to Leksell (interventriculostomy).

Experience with the Leksell drainage (interventriculostomy) in 21 patients is reported. Apart from an account of the technical details and the diagnostic requirements, the indications are also discussed. Apart from the "classic" indications are in a stenosis or restoration of the aqueduct in non-tumourous processes, we see a second reasonable field of application in subtotally resected posterior fossa tumours, when there is the possibility of a recurrence. In these cases the timely use of drainage can save a further operation. In addition, it can be used to forestall an immediate postoperative occlusion of the aqueduct due to oedema in cases in which a tumour was removed from the rostral part of the fourth ventricle. Compared to the common internal shunt procedures, the Leksell drainage shows a definitely greater functional security, equivalent to the Torkildsen drainage.