Ersoy Kocabicak

Current perspectives on deep brain stimulation for severe neurological and psychiatric disorders

Deep brain stimulation (DBS) has become a well-accepted therapy to treat movement disorders, including Parkinson’s disease, essential tremor, and dystonia. Long-term follow-up studies have demonstrated sustained improvement in motor symptoms and quality of life. DBS offers the opportunity to selectively modulate the targeted brain regions and related networks. Moreover, stimulation can be adjusted according to individual patients’ demands, and stimulation is reversible. This has led to the introduction of DBS as a treatment for further neurological and psychiatric disorders and many clinical studies investigating the efficacy of stimulating various brain regions in order to alleviate severe neurological or psychiatric disorders including epilepsy, major depression, and obsessive–compulsive disorder. In this review, we provide an overview of accepted and experimental indications for DBS therapy and the corresponding anatomical targets.

Deep brain stimulation of the subthalamic nucleus in Parkinson's disease: Surgical technique, tips, tricks and complications

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become a frequently performed surgery in patients with advanced Parkinsons disease. The technique has been further refined throughout the years by improved imaging techniques, advanced neurophysiological recording possibilities, and advances in hardware and software technology. In addition, the complications, which can be divided into surgery-related, target-related, and hardware-related complications, were better recognised and managed. In this review, we describe our experience specifically with the surgery of STN DBS in the light of the existing literature. Tips and tricks, complications and their management are the main elements of this article. In addition, we provide scientific information from our research and other groups in specific sections.

The antidepressant effects of ventromedial prefrontal cortex stimulation is associated with neural activation in the medial part of the subthalamic nucleus

The nucleus accumbens (NAc), ventromedial prefrontal cortex (vmPFC), and cingulate gyrus (Cg) are key regions in the control of mood-related behaviors. Electrical stimulation of these areas induces antidepressant-like effects in both patients and animal models. Another structure whose limbic connections are receiving more interest in the context of mood-related behaviors is the medial part of the subthalamic nucleus (STN). Here, we tested the hypothesis that the mood-related effects of NAc, vmPFC, and Cg are accompanied by changes in the neural activity of the STN. We performed high-frequency stimulation (HFS) of the NAc, vmPFC, and Cg. Animals were behaviorally tested for hedonia and forced swim immobility; and the cellular activities in the different parts of the STN were assessed by means of c-Fos immunoreactivity (c-Fos-ir). Our results showed that HFS of the NAc and vmPFC, but not Cg reduced anhedonic-like and forced swim immobility behaviors. Interestingly, there was a significant increase of c-Fos-ir in the medial STN with HFS of the vmPFC, but not the NAc and Cg as compared to the sham. Correlation analysis showed that the medial STN is associated with the antidepressant-like behaviors in vmPFC HFS animals. No behavioral correlation was found with respect to behavioral outcome and activity in the lateral STN. In conclusion, HFS of the vmPFC induced profound antidepressant-like effects with enhanced neural activity in the medial part of the STN.

Transgenic Rat Models of Huntington’s Disease

Several animal models for Huntingtons disease (HD) have been created in order to investigate mechanisms of disease, and to evaluate the potency of novel therapies. Here, we describe the characteristics of the two transgenic rat models: transgenic rat model of HD (fragment model) and the Bacterial Artificial Chromosome HD model (full-length model). We discuss their genetic, behavioural, neuropathological and neurophysiological features.

Is there still need for microelectrode recording now the subthalamic nucleus can be well visualized with high field and ultrahigh MR imaging

Citation: Kocabicak E, Alptekin O, Ackermans L, Kubben P, Kuijf M, Kurt E, Esselink R and Temel Y (2015) Is there still need for microelectrode recording now the subthalamic nucleus can be well visualized with high field and ultrahigh MR imaging? Front. Integr. Neurosci. 9:46. doi: 10.3389/fnint.2015.00046 Is there still need for microelectrode recording now the subthalamic nucleus can be well visualized with high field and ultrahigh MR imaging?

Does probe's eye subthalamic nucleus length on T2W MRI correspond with microelectrode recording in patients with deep brain stimulation for advanced Parkinson's disease?

AIM Subthalamic nucleus (STN) deep brain stimulation (DBS) has become a well-accepted treatment for patients with advanced Parkinsons disease (PD). During surgical planning for DBS, the length of the STN is taken into account and verified during microelectrode recording (MER) intraoperatively. Here, we addressed the question to which extent the length of the STN measured with the T2 weighted MRI in the probes eye view corresponded with the intraoperatively determined length of the STN with MER. MATERIAL AND METHODS We included 10 consecutive Parkinsons disease patients who underwent STN DBS surgery. The length of the STN in the probes eye view mode was calculated along the trajectory of the central MER electrode crossing the STN. RESULTS Our analysis showed no statistical difference between the length of the STN measured with the T2 weighted probes eye view mode and the MER (right STN length 5.8 ± 0.9 mm MRI vs. 6.3 ± 0.5 mm MER, p > 0.05; left STN length 5.6 ± 0.4 mm MRI vs 5.8 ± 1 mm MER, p > 0.05). CONCLUSION This means that the entry and the exit of the STN can be adequately estimated using the probes eye view preoperatively.

A detailed analysis of intracerebral hemorrhages in DBS surgeries

OBJECTIVES Deep brain stimulation is nowadays a frequently performed surgery in patients with movement disorders, intractable epilepsy, and severe psychiatric disorders. The most feared complication of this surgery is an intracerebral hemorrhage due to the electrode placement, either for intraoperative electrophysiology (microelectrode recording) and/or implantation of the final electrode (macroelectrode). Here, we have investigated the risk of developing an intracerebral hemorrhage in our cohort of deep brain stimulation patients over a period of 15 years. PATIENTS AND METHODS We have collected demographic data and analyzed the effect of performing surgery with single-electrode versus multiple electrode guided DBS. The effect of using single-dose versus double-dose contrast enhanced MRI to visualize vessels for the electrode trajectory planning has been investigated as well. RESULTS We have found that the overall calculated risk of an intracerebral hemorrhage in our series was 1.81% per patient, 0.3% per recording electrode and 0.23% per brain insertion. While three out of four patients recovered without neurological deficits, there was one mortality in a patient with cardiovascular comorbidities. Statistical comparisons between the groups of single-electrode versus multiple electrode guided surgery and single-dose gadolinium versus double-dose contrast enhanced MRI revealed no significant differences. In addition, there was no meaningful correlation between the age at surgery and the risk of bleeding. CONCLUSION We have found that the risk of developing an intracerebral hemorrhage due to deep brain stimulation surgery is low. The clinical course of the patients with an intracerebral hemorrhage was generally favorable.

Has admission blood pressure any prognostic value in patients with subarachnoid hemorrhage: an emergency department experience.

Hypertension is a well‐known risk factor for the development and rupture of cerebral aneurysms. The authors conducted a study to investigate the prognostic value of admission blood pressure (BP) on prognosis in patients with subarachnoid hemorrhage (SAH). Two hundred patients with SAH were divided into two groups according to Hunt Hess score (good prognosis: 1 to 3, and poor prognosis: 4 and 5) and according to death in hospital (surveyed and died). The prognostic factors of SAH and BP changes according to Hunt Hess scores in the acute stages of the event were evaluated. Admission mean arterial BP values of the patients who died in hospital were significantly lower than in the patients who were surveyed (P=.026). The admission mean arterial BP values were found to be lower in the poor prognostic patients (Hunt Hess score of 4 and 5) (P<.001). Decreased admission BP values were found to be associated with poor prognosis and mortality.

Conversion of local anesthesia-guided deep brain stimulation of the subthalamic nucleus to general anesthesia.

BACKGROUND Deep brain stimulation of the subthalamic nucleus (STN) is a widely applied procedure in the treatment of patients with advanced Parkinson disease and is generally performed under local anesthesia. Here we report our experience with the conversion to general anesthesia in two patients with advanced Parkinson disease because of fear reactions intraoperatively. CASE DESCRIPTION Patients received general anesthesia with propofol and were implanted with electrodes at the level of STN guided by multiple-microelectrode electrophysiological recordings after obtaining informed consent. During the recordings the propofol levels were reduced. Postoperative clinical assessments showed marked improvements of motor disability with significant reductions of dopaminergic medication. CONCLUSION Our case observations document the possibility of fear reactions intraoperatively and show the possibility of conversion to general anesthesia with a successful outcome.

Final Electrode Position in Subthalamic Nucleus Deep Brain Stimulation Surgery: A Comparison of Indirect and Direct Targeting Methods

AIM High frequency stimulation of the subthalamic nucleus (STN) is nowadays a widely performed surgery for patients with Parkinsons disease (PD). The field has witnessed a shift from indirect targeting to direct targeting. The question arises whether this change has influenced the final electrode position in STN deep brain stimulation surgery. To address this question, we compared the final electrode positions in atlas-based and magnetic resonance-based targeting methods in our series. MATERIAL AND METHODS We performed a database review of the surgeries performed in three affiliated centers. RESULTS We have found that with the shift to direct imaging, three key changes have taken place. The first is that the number of microelectrode recording trajectories has decreased by approximately 1 microelectrode. Secondly, the central trajectory has been chosen as the final position in more patients, and the third change is that direct targeting has improved the laterality of the targeting significantly. CONCLUSION Direct targeting has changed routine clinical practice, thereby further refining the surgical approach.