@article{MTMT:1033952, title = {Biportal endoscopic management of third ventricle tumors in patients with occlusive hydrocephalus: Technical note}, url = {https://m2.mtmt.hu/api/publication/1033952}, author = {Vető, Ferenc and Horvath, Z and Dóczi, Tamás Péter}, doi = {10.1097/00006123-199704000-00048}, journal-iso = {NEUROSURGERY}, journal = {NEUROSURGERY}, volume = {40}, unique-id = {1033952}, issn = {0148-396X}, abstract = {OBJECTIVE: To present the feasibility and advantages of the biportal endoscopic management of posterior third ventricle tumors. As a result of recent developments in neuroendoscopy, classical third ventriculostomy has become a standard single burr hole procedure and a real alternative to shunting in the treatment of occlusive hydrocephalus. In patients with third ventricle tumors occluding the aqueduct, the acute development of hydrocephalus may often precede debilitating focal symptoms and signs. Forty percent of those tumors are radiosensitive, rendering craniotomy unnecessary. The goal of primary management is the alleviation of raised intracranial pressure and determination of the histological nature of the tumor. Cerebrospinal fluid shunting and the performance of a computed tomography- or magnetic resonance imaging-guided biopsy are generally suggested as the methods of choice. METHODS: Three patients with posterior third ventricle tumors and acute hydrocephalus were treated in one session by computed tomography-guided endoscopic third ventriculostomy and endoscopic tumor biopsy was performed by means of two rigid ventriculoscopes. RESULTS: Ventriculostomy was performed in three patients, and tumor biopsy was performed in two patients. The maximum 40-minute operation did not involve mortality or morbidity. Histological findings were established in all patients. In two patients with malignant infiltrative tumors, postoperative radiotherapy was used; in one patient with a small cavernoma, no further measures were taken. At the 6-month follow-up, flow-sensitive magnetic resonance imaging confirmed ventriculostomy patency in all patients. CONCLUSION: The biportal endoscopic approach allowed independent visual control of both procedures, safe passages of the ventriculoscopes via the narrow foramen of Monro, and facile control of the intracranial pressure in the ventricles via the available four irrigation channels during the performance of tumor biopsy and fenestration of the floor of the third ventricle. In selected patients with infiltrating posterior third ventricle tumors, this procedure and postoperative radiotherapy may be an alternative to direct surgery or to shunting and performance of image-guided biopsy.}, year = {1997}, eissn = {1524-4040}, pages = {871-875} } @article{MTMT:1033963, title = {MEASUREMENTS OF REGIONAL CEREBRAL BLOOD-FLOW AND BLOOD-FLOW VELOCITY IN EXPERIMENTAL INTRACRANIAL HYPERTENSION - INFUSION VIA THE CISTERNA MAGNA IN RABBITS}, url = {https://m2.mtmt.hu/api/publication/1033963}, author = {Barzó, Pál and Dóczi, Tamás Péter and Csete, K and Buza, Z and Bodosi, M}, doi = {10.1227/00006123-199106000-00006}, journal-iso = {NEUROSURGERY}, journal = {NEUROSURGERY}, volume = {28}, unique-id = {1033963}, issn = {0148-396X}, abstract = {Cerebral blood flow velocity, as measured in the intracranial segment of the internal carotid artery by transcranial Doppler sonography via the transorbital route, and regional cerebral blood flow and volume in corresponding cortical areas, as measured by the hydrogen clearance technique, were recorded for eight New Zealand White rabbits subjected to infusion via the cisterna magna to elevate intracranial pressure. In the lower range of autoregulation, that is, at perfusion pressures between 80 and 40 mm Hg and even lower, the changes in cerebral blood flow velocity and cerebral blood flow showed a strong correlation (0.86) under conditions of standard pCO2 (PaCO2 = 35 +/- 2 mm Hg). Autoregulation was exhausted at 40 mm Hg, and the cerebrovascular resistance was minimal. Below this perfusion pressure, the cerebral blood flow and volume dropped sharply, whereas the cerebrovascular resistance gradually increased, indicating that, despite the maximally dilated resistance vessels, intracranial hypertension causes vascular resistance to increase, possibly via blocking of the venous outflow. Our results confirmed that noninvasive and easily (even at bedside) applicable measurements of changes in cerebral blood flow velocity could be a substitute for the cumbersome and expensive isotope measurements of cerebral blood flow in patients with intracranial hypertension.}, year = {1991}, eissn = {1524-4040}, pages = {821-825}, orcid-numbers = {Barzó, Pál/0000-0001-8717-748X} }