Dušan Hrabovský

Factors responsible for early postoperative mental alterations after bilateral implantation of subthalamic electrodes.

Abstract Introduction: Early postoperative mental changes are the most frequent problem after bilateral subthalamic electrode implantation. The study aims to find an association between them and factors related to patient, disease and surgery, including the size of the third ventricle as brain atrophy marker. Material and methods: The study included 80 patients with bilateral subthalamic electrodes implanted for motor complications of Parkinson’s disease (PD). Patients’ age, disease and motor complications duration, medication, neuropsychological tests, surgical reports, third ventricle length (intercommissural distance) and width (intermammillary distance) were analysed. Results: Early mental alterations requiring treatment were observed in 25.0% of patients with higher age being significant predictor. The duration of PD motor complications, L DOPA equivalent dose, DSR Mattis, third ventricle length and width were not statistically significant predictors. The incidence of postoperative mental alteration with intermammillary distance > 8 mm was 60%. The percentage of left sided electrodes implanted in anterior trajectory is significantly higher in patients with early mental changes. Conclusions: Higher age is a risk factor for early postoperative mental changes, but not disease, late motor complications duration and parameters describing third ventricular size except the excessive intermammillary distance. Left sided electrode implanted in anterior position is a risk factor.

Learning curve in anatomo-electrophysiological correlations in subthalamic nucleus stimulation.

AIM Advances in neuroradiological planning techniques in deep brain stimulation have put the need for intraoperative electrophysiological monitoring into doubt. Moreover intraoperative monitoring prolongs surgical time and there is potential association between the use of microelectrodes and increased incidence of hemorrhagic complications. The aim of this study was to analyze the correlation between the anatomically planned trajectory and the final subthalamic electrode placement after electrophysiological monitoring in patients with Parkinsons disease and its change with the increasing experience of the surgical team. MATERIAL AND METHODS The trajectories of right (first implanted) and left electrodes were compared in the first 50 patients operated on (Group 1) and the next 50 patients (Group 2). RESULTS In Group 1, 52% of central trajectories were on the right and 38% on the left; in Group 2, the percentage of central trajectories was 76% on the right and 78% on the left; the difference was statistically significant (p=0.021 and 0.001). The difference in the percentage of posterior trajectories reflecting brain shift between the right and left sides was statistically insignificant in Groups 1 (26% and 28%, p=0.999) and 2 (18% and 12%, p=0.549). The percentage of bilateral central electrodes was 14% and 62% in Groups 1 and 2, respectively. CONCLUSION The correlation between anatomically planned trajectory and final electrode placement markedly improves with the number of patients. However the significant percentage of patients with final electrode trajectory differing from anatomically planned target supports the use of intraoperative monitoring.

The Role of Palliative Radiotherapy in Bleeding from Locally Advanced Gastrointestinal Tumors

Backround: Because of the dismal prognosis of untreated brain lymphoma early histological verification using stereobiopsy is decisive for patient with this disease. The study analysed the diagnostic yield of stereobiopsy in brain lymphoma patients with respect to prebiopsy corticosteroid administration. PATIENTS AND METHODS Patients with brain lymphomas were identified in a group of 162 stereotactic biopsies (108 frame-based and 54 frameless) of patients harboring suspected brain tumor. Non conclusive biopsies were reevaluated to exclude the possibility of missed lymphoma. RESULTS Total 9 patients (8.3%) and 4 patients (7.4%) had lymphomas in the frame-based and frameless stereobiopsy groups, resp. In 10 patients, corticosteroid treatment of perifocal brain oedema was conducted continually up until biopsy (including one patient with corticotherapy for pulmonary disease). Lesion regression was observed in 6 of these patients. Transient lesion remission was observed during corticotherapy in one patient with lesion recurrence after steroid discontinuation. In 2 patients, corticosteroids were not administered before biopsy. The results of stereobiopsy were inconclusive in 8 patients (4.9%). Before biopsy, the possibility of brain lymphoma was considered in 3 patients, but the final diagnoses were autoimmune vasculitis, histological changes after embolic events from the thrombosed pulmonary veins in pulmonary malformation and local inflammation. CONCLUSION Although the extent of brain lymphoma decreased after corticosteroid administration, corticotherapy does not exclude valid diagnostic biopsy.Key words: brain lymphoma - stereotaxic techniques - frameless stereotaxy - stereotactic biopsy - corticosreroids Part of the message was presented on XLI. Brno Oncological Days within the Glio Meeting and published in the form of a short abstract. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 27. 5. 2017Accepted: 2. 7. 2017.

Neuroonkologické aspekty u nemocných s farmakorezistentní epilepsií

Poruchy kortikalniho vývoje a benigni tumory mozku jsou castou přicinou dlouhotrvajici farmakorezistentni epilepsie u dětských i dospělých nemocných. Tito nemocni jsou operacně řeseni a nasledně sledovani v epileptochirurgických centrech. Progrese gradingu mozkových tumorů u nemocných s farmakorezistentni epilepsii je vzacným problemem a rozvoj maligniho tumoru mozku u nemocných s malformacemi kortikalniho vývoje mozku je publikovan zcela výjimecně. Ve sděleni prezentujeme dvě kazuistiky nemocných s farmakorezistentni epilepsii s neocekavaným rozvojem maligniho tumoru mozku. U jedne nemocne s chronickou epilepsii doslo k velmi casne progresi gradingu opakovaně histologicky verifikovaneho nizkostupňoveho gliomu s finalnim nalezem glioblastomu. U druheho nemocneho byl popsan výjimecný rozvoj glioblastomu v terenu hemimegalencefalie.