ENDOSCOPIC FENESTRATION OF THE 3RD VENTRICULAR FLOOR IN AQUEDUCTAL STENOSIS

Six endoscopic fenestrations of the 3rd ventricular floor have been pe rformed in patients with stenosis (SAS) of the aqueduct of Sylvius in our institute during the last two years. The endoscopic intraventricul ar landmarks were the Monro's foramen followed by the mamillary bodies . The fenestration instrument was a monopolar coagulation wire, the di latation instrument was a balloon catheter. The patients included two newborns and four adults. The two newborns developed a recurrent hydro cephalus after 2 months. The four adults remained well after the opera tion. The only complication was edema (SIADH syndrome) in one case for 24 hours. Flow sensitised phase MRI showed a mirroring in the presten otic CSF pulsation curve preoperatively, This, in combination with an increased intraventricular pulsation, is a sign of reduced capacity of the subarachnoid space at the cerebral surface. The postoperative pat ency of the fenestration with diminished intraventricular pulsation ca n be demonstrated with ECG retrogated phase MRI. There was a slow and incomplete decrease of the preoperative enlarged ventricular size. Thi s operative method is a low-risk, minimal invasive alternative method to shunt implantation in adults with SAS.