0000000000498411

AUTHOR

K. Ungersböck

Results of 200 intracranial stereotactic biopsies

200 stereotactic biopsies were evaluated. The validity of the intraoperative histopathological results were compared with the final diagnosis using conventional embedding and staining techniques. Further comparison between the histology of the biopsy and the post mortem or open operative findings were possible in 41 cases. Discrepancy was found in one case regarding the tumor detection, and in three cases regarding the tumor grading. The mortality in our patients was 1% and the morbidity 3%. Stereotactical biopsy had a low risk even in deep brain regions such as basal ganglia, mesencephalon, and pons. At the same time the high histologic validity makes the CT-guided stereotactical biopsy re…

research product

Stereotaktische Biopsie von Hirntumoren: Vergleich von CT-und MR-gesteuerter Berechnung

Bei 3 Patienten mit Hirntumor wurde eine stereotaktische Biopsie nach Zielpunktberechnung uber Computertomographie (CT) und Magnetresonanztomographie (MR) durchgefuhrt. Die beiden Techniken werden miteinander verglichen und ihre Vor-und Nachteile diskutiert.

research product

CT-guided stereotactic biopsy aided by Doppler ultrasonic vascular monitoring

The use of a 20 MHz pulsed Doppler technique during stereotactic brain tumour biopsies is described. By means of a miniaturized ultrasonic probe the tissue planned for biopsy was investigated for vessel signals. Out of 41 patients, with this technique a flow-pulse curve in front of the biopsy cannula was registered in 14 cases. In 9 cases one pulse curve was determined and in 5 cases two or more flow curves were found, indicating the presence of arterial vessels. The depth of the vessels signal could be localized and this area avoided for biopsy sampling. In a series of 41 stereotactic biopsies carried out in this way there was no intra-operative haemorrhage or postoperative haematoma.

research product

Aneurysm surgery of patients in poor grade condition. Indications and experience

Out of a total of 196 patients admitted with aneurysmal subarachnoid haemorrhage (SAH) to the neurological department in Mainz over a 42 month period, 48 patients (24.5%) were considered as grade IV or V on admission. Aneurysm surgery within 48 hours after SAH was performed in 56.3% of these patients, 2% were operated between day 3 and 7 and 16.6% were operated after day 7. 25% did not undergo operation because of severe neurological deficit and brain damage. The overall outcome according to the Glasgow outcome scale in the surgically treated group was full recovery in 11.1%, moderate disability in 16.7%, severe disability in 47.2%, vegetative state in 2.8% and death in 22.2%. All patients …

research product

Cerebral blood flow alterations in a rat model of cerebral sinus thrombosis.

Outcome from sinus vein thrombosis is very variable, with symptoms from headache to coma. Experimental findings suggest that an involvement of cortical veins is necessary to affect the cerebral microcirculation. Laser Doppler flowmetry was used to investigate the regional and temporal changes in local cortical blood flow after experimental occlusion and thrombosis of the superior sagittal sinus and tributary cortical veins in rats. Thrombosis was induced by slow injection of kaolin-cephalin suspension after frontal and caudal ligation of the sagittal sinus in rats. Local cerebral blood flow was measured by laser Doppler flowmetry and correlated with parenchymal damage found 24 hours after i…

research product

Evaluation of collateral flow capacity in patients with vascular or tumorous lesions of the skull base by Doppler sonography

In 12 patients with vascular or tumorous lesions of the skull base, the collateral flow capacity was examined by transcranial Doppler sonography and carotid compression studies. In four patients no cross flow mechanism was found, in two patients the test remained unclear, and in six patients the examination suggested a good collateral flow capacity. However, for this application of Doppler sonography no borderlines have yet been defined and thus interpretation is difficult. Intraoperative Doppler sonography was used in five patients and proved to be helpful for localisation of the internal carotid artery within skull base tumors.

research product

The preoperative assessment of stroke risk in lesions involving the internal carotid artery.

Patients with vascular or tumourous lesions involving the internal carotid artery are at risk of damage or occlusion of this vessel during surgical or endovascular procedures. To assess the stroke risk transcranial Doppler aided carotid compression tests were performed in 82 patients. Based on changes of blood flow velocity (BFV), pulsatility index, systolic/diastolic ratio and length of transient hyperaemic response three groups could be differentiated. Patients in group A (31%) showed only a slight reaction of BFV and were at minimal risk in case of carotid occlusion. Patients in group B (52%) underwent a distinct decrease of Doppler readings with partial improvement and were considered t…

research product

Transcranial Doppler and Cortical Microcirculation at Increased Intracranial Pressure and during the Cushing Response

The effect of increased intracranial pressure on the flow velocity of the basilar artery was measured with transcranial ultrasonic Doppler in New Zealand White rabbits under alpha-chloralose anesthesia and artificial respiration. Laser Doppler flowmetry served to study changes of the cortical microcirculation. The results confirm a high inverse correlation of the diastolic flow velocity, the pulsatility index, and the resistance index with the cerebral perfusion pressure (CPP). During acute intracranial hypertension, however, these parameters do not show a good correlation with the local cortical blood flow. The absence of a correlation was evident over a wide CPP range down to values of 35…

research product