Intraoperative electrophysiological monitoring determines the final electrode position for pallidal stimulation in dystonia patients.

Background: Bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective treatment for refractory dystonia. Neuroradiological target and stimulation electrode trajectory planning with intraoperative microelectrode recordings (MER) and stimulation are used. With improving neuroradiological techniques, the need for MER is in dispute mainly because of the suspected risk of hemorrhage and the impact on clinical post DBS outcome. Objective: The aim of the study is to compare the preplanned GPi electrode trajectories with final trajectories selected for electrode implantation after electrophysiological monitoring and to discuss the factors potentially responsible for differences between preplanned and final trajectories. Finally, the potential association between the final trajectory selected for electrode implantation and clinical outcome will be analyzed. Methods: Forty patients underwent bilateral GPi DBS (right-sided implants first) for refractory dystonia. The relationship between preplanned and final trajectories (MicroDrive system) was correlated with patient (gender, age, dystonia type and duration) and surgery characteristics (anesthesia type, postoperative pneumocephalus) and clinical outcome measured using CGI (Clinical Global Impression parameter). The correlation between the preplanned and final trajectories together with CGI was compared between patients 1-20 and 21-40 for the learning curve effect. Results: The trajectory selected for definitive electrode implantation matched the preplanned trajectory in 72.5% and 70% on the right and left side respectively; 55% had bilateral definitive electrodes implanted along the preplanned trajectories. Statistical analysis did not confirm any of the studied factors as predictor of the difference between the preplanned and final trajectories. Also no association between CGI and final trajectory selected for electrode implantation in the right/left hemisphere has been proven. The percentages of final electrodes implanted along the preplanned trajectory (the correlation between anatomical planning and intraoperative electrophysiology results) did not differ between patients 1-20 and 21-40. Similarly, there were no statistically significant differences in CGI (clinical outcome) between patients 1-20 and 21-40. Conclusion: The final trajectory selected after electrophysiological study differed from the preplanned trajectory in a significant percentage of patients. No predictor of this difference was identified. The anatomo-electrophysiological difference was not predictive of the clinical outcome (as measured using CGI parameter).

Deep Brain Stimulation during Pregnancy and Delivery: Review of Current Literature.

Deep brain stimulation (DBS) is an established method in the treatment of not only Parkinson's disease motor complications but also dystonia and tremor, and there are data supporting the efficacy of DBS in epilepsy and some psychiatric problems. The alleviation of the neurologic problems may enable females of childbearing age to consider pregnancy because of being able to take care of their child. The aim of the study is to provide a review of the data available on the effect of DBS on the course of pregnancy and delivery in patients suffering from diseases amenable for DBS treatment (Parkinson's disease, dystonia, obsessive compulsive disorder, Tourette's syndrome, epilepsy). Although data available in the literature on pregnancy and childbirth in patients with an implanted active DBS system are limited to small case series and case reports, the number of younger patients implanted with DBS systems will potentially require more attention beyond specialized DBS centers. In emergency deliveries, general obstetricians and neurosurgeons should be provided with a protocol to prevent injuries to the implanted system with potentially devastating consequences for the patient.

Successful asymmetrical deep brain stimulation using right subthalamic and left pallidal electrodes in a patient with Parkinson's disease.

PURPOSE: Despite the best efforts of neurologists, the results of pharmacotherapy in the late stages of Parkinson's disease are often disappointing and accompanied by debilitating side effects. Under these circumstances, deep brain stimulation is a viable treatment option. The aim of the meticulous pre-surgical planning is not only precise electrode implantation, but also the avoidance of intraoperative vascular conflicts potentially causing intracerebral bleeding. MATERIAL AND METHODS: In this report, we present a patient with early-onset Parkinson's disease whose cerebral vascular anatomy precluded standard bilateral subthalamic nucleus electrode implantation. Initially, right subthalamic stimulation alone provided a very mild clinical benefit that was not reflected in the patient's quality of life. In this patient, an unusual configuration of intracerebral electrodes with right subthalamic and left pallidal stimulation electrodes was applied 15 months after the initial subthalamic electrode implantation. RESULTS: The procedure has had a highly beneficial long-term effect without any significant complications. The greatest improvement was noted using the setting 1.8 V, 130 Hz, 90 µs at the right side (STN) and 3.7 V, 130 Hz, 120 µs at the left side (GPi). This allowed the patient to return to his daily life activities. CONCLUSIONS: The reported case provides a new perspective of treatment possibilities in complex functional neurosurgical cases requiring exceptional individualisation of the treatment approach.

The Results of Neuroendoscopic Surgery in Patients with Posttraumatic and Posthemorrhagic Hydrocephalus.

BACKGROUND: Posttraumatic hydrocephalus (PTH) and posthemorrhagic hydrocephalus (PHH) were previously considered not suitable for neuroendoscopic treatment. New hydrocephalus theories support possible successful neuroendoscopy in such patients. METHODS: This study presents the results of neuroendoscopy in PTH and PHH with a background analysis. From 130 hydrocephalic patients after neuroendoscopic surgeries, 35 cases with PTH (n = 11) or PHH (n = 24; acute: n = 9, subacute: n = 10, chronic: n = 5) were found. The success rate (Glasgow Outcome Scale [GOS] score 4 or 5 without shunt) and clinical outcome (GOS score) of endoscopic third ventriculostomy (ETV) were analyzed. During the study period, 34 patients had ventriculoperitoneal shunts implanted, including 2 PTH and 5 PHH patients (all chronic). RESULTS: The success rate of ETV in PTH was 54.5%. In acute PHH, the success rate was 33.3%, 42.8% after excluding devastating hematomas. A post-ETV shunt was implanted in 1 patient (massive subarachnoid hemorrhage [SAH]) with final GOS score of 5. In subacute cases, the ETV success rate was 40% (no post-ETV shunts). In chronic PHH, only 1 patient with a GOS score of 5 was shunt-free (20%). The cause of ETV failure was massive SAH. Low final GOS score was caused by the extent of intracerebral bleeding or extracranial problems. The main indications for primary shunt implantation in PTH and PHH were infectious complications. The rate of good outcomes was 0% in PTH and 40% in PHH. CONCLUSIONS: The best results of neuroendoscopy were achieved in PTH and acute PHH. ETV failures were associated with massive SAH; arachnoid cistern blockage and scarring precludes ETV success.

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 Parkinson"s 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.

[Surgeons and Neurosurgeons as Nobel Prize Winners]. / Chirurgové a neurochirurgové jako laureáti Nobelovy ceny.

Since 1901 Nobel Prize is awarded for exceptional achievements in physics, chemistry, literature, peace, economy (since 1968) and medicine or physiology. The first aim of the paper is to provide an overview of surgeons - winners of Nobel Prize for medicine or physiology. Although the prominent neurosurgeons were frequently nominated as Nobel Prize candidates, surprisingly no neurosurgeon received this prestigious award so far despite that the results of their research transgressed the relatively narrow limits of neurosurgical speciality.The most prominent leaders in the field of neurosurgery, such as Victor Horsley, Otfrid Foerster, Walter Dandy and Harvey Cushing are discussed from the point of their nominations. The overview of the activity of the Portuguese neurologists and Nobel Prize Winter in 1949 Egas Moniz (occasionally erroneously reported as neurosurgeon) is also provided. Although his work on brain angiography has fundamentally changed the diagnostic possibilities in neurology and neurosurgery, he was eventually awarded Nobel Prize for the introduction of the currently outdated frontal lobotomy.The fact that none of the above mentioned prominent neurosurgeons has not been recognised by Nobel Prize, may be attributed to the fact that their extensive work cannot be captured in a short summary pinpointing its groundbreaking character.