Stereotactic and Functional Neurosurgery

INTRODUCTION: Intraoperative microelectrodes recording with the Ben Gun microdrive system are often used during DBS surgery. An accurate location of these microelectrodes will directly influence the interest of this recording. We have studied the imprecision of implantation of these microelectrodes. METHODS: We have analyzed the stereotactic position of 135 microelectrodes implanted with the Ben Gun microdrive during DBS surgery of 16 patients with advanced Parkinson's disease...

BACKGROUND: Essential tremor (ET) patients present with both motor and non-motor symptoms including depression. Although deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) is used to treat motor symptoms of ET, there is no consensus as to how VIM DBS influences non-motor symptoms, specifically depression. OBJECTIVE: The objective of this study was to conduct a meta-analysis of available studies investigating change in pre- to postoperative depression scores as measured by Beck Depression Inventory (BDI) in ET patients receiving VIM DBS...

INTRODUCTION: The success of deep brain stimulation (DBS) treatment depends on several factors, including proper patient selection, accurate electrode placement, and adequate stimulation settings. Another factor that may impact long-term satisfaction and therapy outcomes is the type of implantable pulse generator (IPG) used: rechargeable or non-rechargeable. However, there are currently no guidelines on the choice of IPG type. The present study investigates the current practices, opinions, and factors DBS clinicians consider when choosing an IPG for their patients...

INTRODUCTION: Accurate and precise delineation of the globus pallidus pars interna (GPi) and subthalamic nucleus (STN) is critical for the clinical treatment and research of Parkinson's disease (PD). Automated segmentation is a developing technology which addresses limitations of visualizing deep nuclei on MR imaging and standardizing their definition in research applications. We sought to compare manual segmentation with three workflows for template-to-patient nonlinear registration providing atlas-based automatic segmentation of deep nuclei...

INTRODUCTION: Magnetic resonance-guided focused ultrasound (MRgFUS) represents an incisionless treatment option for essential or parkinsonian tremor. The incisionless nature of this procedure has garnered interest from both patients and providers. As such, an increasing number of centers are initiating new MRgFUS programs, necessitating development of unique workflows to optimize patient care and safety. Herein, we describe establishment of a multi-disciplinary team, workflow processes, and outcomes for a new MRgFUS program...

BACKGROUND: Deep brain stimulation has become an established technology for the treatment of patients with a wide variety of conditions, including movement disorders, psychiatric disorders, epilepsy, and pain. Surgery for implantation of DBS devices has enhanced our understanding of human physiology, which in turn has led to advances in DBS technology. Our group has previously published on these advances, proposed future developments, and examined evolving indications for DBS. SUMMARY: The crucial roles of structural MR imaging pre-, intra-, and post-DBS procedure in target visualization and confirmation of targeting are described, with discussion of new MR sequences and higher field strength MRI enabling direct visualization of brain targets...

BACKGROUND: The treatment of medically refractory patients with chronic short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is challenging. Stereotactic radiosurgery targeting the trigeminal nerve and sphenopalatine ganglion (SPG) has been used as a less-invasive treatment. The outcomes of this procedure have been described in a few case reports. OBJECTIVES: The objective of the study was to report on the effect of Gamma Knife radiosurgery (GKRS) in 5 patients with chronic SUNCT...

Responsive neurostimulation (RNS) has well-established efficacy in patients with identifiable seizure foci. Emerging evidence suggests the feasibility of expanding this treatment to patients with nonfocal or multifocal epileptic profiles with thalamic targeting. Our institution performed two successful implantations of thalamic RNS (tRNS) targeting the centromedian nucleus of the thalamus (CMT), and 1-year postoperative outcomes are provided. Additionally, a literature review of all reported tRNS was conducted...

INTRODUCTION: The aim of this study was to determine the safety and feasibility of convection-enhanced delivery of autologous cerebrospinal fluid (CSF) for enhancing intraoperative magnetic resonance imaging (MRI) of the basal ganglia during stereotactic neurosurgery. METHODS: This pilot study was conducted in 4 patients with Parkinson's disease (PD) who underwent MRI-guided deep brain stimulation of the globus pallidus internus (GPi). CSF was obtained via lumbar puncture after general anesthesia and prior to incision...

INTRODUCTION: With the advent of MR-guided focused ultrasound, the importance of the efficacy and safety of bilateral ventral intermediate (Vim) thalamotomy for essential tremor (ET) has increased. However, reports on bilateral Vim thalamotomy for ET remain scarce. METHODS: To review the results and complications of bilateral Vim thalamotomy for the treatment of ET in the upper extremities, we retrospectively analyzed the patients with ET who underwent bilateral Vim thalamotomy with radiofrequency (RF) thermal coagulation...

Magnetic resonance-guided high-intensity focused ultrasound (MRgFUS) is a rapidly developing technique used for tremor relief in tremor-predominant Parkinson's disease (PD) and essential tremor that has demonstrated successful results. Here, we describe the neuropathological findings in a woman who died from a fall 10 days after successful MRgFUS for tremor-predominant PD. Histological analysis demonstrates the characteristic early postoperative MRI findings including 3 distinct zones on T2-weighted imaging: (1) a hypointense core, (2) a hyperintense region with hypointense rim, and (3) a slightly hyperintense, poorly marginated surrounding area...

INTRODUCTION: Essential tremor (ET) is one of the most prevalent movement disorders in adults and may be highly disabling for some. Magnetic resonance image-guided high-intensity focused ultrasound (MRIgFUS) has been shown to control tremor efficaciously and with acceptable risk. To date, paresthesia and ataxia are the most common adverse effects (AE). Nevertheless, the impact of MRIgFUS thalamotomy on balance is not well established. METHODS: Thirty-two patients underwent MRIgFUS for ET and completed 6 months of follow-up...

INTRODUCTION: The objective of the study is to determine if high-frequency (1 kHz) spinal cord stimulation (SCS) is better than low-frequency SCS for pain relief in chronic limb-threatening ischemia (CLTI). METHODS: HEAL-SCS trial was designed as an open-label, parallel-group, single-center randomized study with a 1:1 allocation ratio. The trial was conducted in Meshalkin National Medical Research Center between August 2018 and February 2020. Total 56 patients underwent screening, 50 were enrolled, 6 were rejected...

INTRODUCTION: Haemangioblastoma is a benign, vascular tumour of the central nervous system. Stereotactic radiosurgery (SRS) is increasingly being used as a treatment for spinal lesions to avoid complex surgery, especially in patients with multi-focal tumours associated with von Hippel-Lindau syndrome (VHL). Here, we present the outcomes of patients treated in our centre using a CyberKnife VSI (Accuray, Inc.). METHODS: Retrospective analysis of all patients treated at our institution was conducted...

The vagus nerve has motor, sensory, and parasympathetic components. Understanding the nerve's internal anatomy, its variations, and relationship to the glossopharyngeal nerve are crucial for neurosurgeons decompressing the lower cranial nerves. We present a case report demonstrating the location of the parasympathetic fibres within the vagus nerve rootlets. A 47-year-old woman presented with a 1-year history of medically refractory left-sided glossopharyngeal neuralgia and a more recent history of left-sided hemi-laryngopharyngeal spasm...

INTRODUCTION: As one of the most common medical conditions for which patients seek medical care, chronic pain can be debilitating. The relationship between chronic pain and sleep is thought to be bidirectional, suggesting that treatment of one can be beneficial to the other. There is mounting evidence that spinal cord stimulation (SCS) improves aspects of sleep. How meaningful that is to patients' lives has not been ascertained. OBJECTIVE: The aim of the current study was to further elucidate the effect of SCS on sleep by examining the relationship between pain outcome measures with the insomnia severity index (ISI) and to establish the minimally clinical important difference (MCID), which is defined as the smallest noticeable change that an individual perceives as clinically significant...

INTRODUCTION: Deep brain stimulation (DBS) is a common treatment for a variety of neurological and psychiatric disorders. Recent studies have highlighted the role of neuroimaging in localizing the position of electrode contacts relative to target brain areas in order to optimize DBS programming. Among different imaging methods, postoperative magnetic resonance imaging (MRI) has been widely used for DBS electrode localization; however, the geometrical distortion induced by the lead limits its accuracy...

Deep brain stimulation is an established treatment option for both essential tremor (ET) and Parkinson's disease (PD), although typically targeting different brain structures. Some patients are diagnosed with comorbid ET and PD. Selecting the optimal stimulation target in these patients is challenging. We present a patient with comorbid ET and PD in whom we used bilaterally a single parietal trajectory to align the dentato-rubro-thalamic tract and the subthalamic nucleus. Although parietal trajectories are challenging, we reached satisfactory outcomes for both conditions without complications...

Posterior hypothalamic-deep brain stimulation (pHyp-DBS) has been reported as a successful treatment for reducing refractory aggressive behaviors in patients with distinct primary diagnoses. Here, we report on a patient with cri du chat syndrome presenting severe self-injury and aggressive behaviors toward others, who was treated with pHyp-DBS. Positive results were observed at long-term follow-up in aggressive behavior and quality of life. Intraoperative microdialysis and imaging connectomics analysis were performed to investigate possible mechanisms of action...

INTRODUCTION: Radiosurgery is now a recognized treatment of vestibular schwannoma (VS); however, radiosurgical irradiation sometimes fails to stop tumor growth in the long term. Some changes in MR imaging after radiosurgery that are supposed to be related to permanent tumor control may be observed in patients with failed treatment. The objective of the present study was to evaluate the MRI changes observed early after radiosurgery in a cohort of patients with failed radiosurgery for VS...