Citations

BACKGROUND AND OBJECTIVES: A typical workflow for deep brain stimulation (DBS) surgery consists of head frame placement, followed by stereotactic computed tomography (CT) or MRI before surgical implantation of the hardware. At some institutions, this workflow is prolonged when the imaging scanner is located far away from the operating room, thereby increasing workflow times by the addition of transport times. Recently, the intraoperative O-arm has been shown to provide accurate image fusion with preoperative CT or MR imaging, suggesting the possibility of obtaining an intraoperative localization scan and postoperative confirmation. In this article, we aim to evaluate the compatibility of the stereotactic frame system with the intraoperative O-arm system regarding lead accuracy and surgical flow. METHODS: A total of 17 patients undergoing DBS surgery for movement disorders were evaluated. One patient underwent both the stereotactic CT and O-arm localization, while 16 patients underwent only intraoperative O-arm localization. Following lead placement, intraoperative O-arm imaging was obtained to evaluate the accuracy of the lead placement. Accuracy was defined as the error measured as the distance from the center of the planned trajectory to the cannula. RESULTS: Less than 0.1 mm difference was found between the O-arm imaging technique and CT image localization of the NaviNetics stereotactic head frame in DBS surgery. Of the 16 patients who underwent the intraoperative O-arm imaging alone, the targets included bilateral ventral intermediate nucleus (16 leads), bilateral globus pallidus internus (4 leads), and subthalamic nucleus (12 leads). The mean ± SD radial error in the probe's eye view was 0.71 ± 0.33 mm for n = 32 leads. No tract hemorrhage was observed. CONCLUSION: Intraoperative O-arm imaging can be used safely and effectively for stereotactic registration and lead placement confirmation with the stereotactic system in both awake and asleep DBS surgery.

The distinct impacts of fouling mechanisms on a carbon fiber microelectrode and an Ag/AgCl reference electrode, affecting their performance in neurotransmitter detection via Fast-scan Cyclic Voltammetry.

OBJECTIVE Conventional frame-based stereotactic systems have circumferential base frames, often necessitating deep brain stimulation (DBS) surgery in two stages: intracranial electrode insertion followed by surgical re-preparation and pulse generator implantation. Some patients do not tolerate awake surgery, underscoring the need for a safe alternative for asleep DBS surgery. A frame-based stereotactic system with a skull-mounted "key" in lieu of a circumferential base frame received US FDA clearance. The authors describe the system’s application for single-stage, asleep DBS surgery in 8 patients at their institution and review its workflow and technical considerations. METHODS Eight patients underwent DBS lead insertion and IPG implantation in a single surgical preparation under general anesthesia using the system. Postoperative CT imaging confirmed lead placement. RESULTS Eight patients underwent implantation of 15 total leads targeting the ventral intermediate nucleus (4 patients), globus pallidus internus (GPi; 3 patients), and subthalamic nucleus (STN; 1 patient). Intraoperative microelectrode recording was conducted for GPi and STN targets. Postoperative CT imaging revealed a mean ± SD radial error of 1.24 ± 0.45 mm (n = 15 leads), without surgical complications. CONCLUSIONS The stereotactic system facilitated safe and effective asleep, single-stage DBS surgery, maintaining traditional lead accuracy standards.

Abstract Tourette syndrome is a childhood-onset neuropsychiatric disorder characterized by intrusive motor and vocal tics that can lead to self-injury and deleterious mental health complications. While dysfunction in striatal dopamine neurotransmission has been proposed to underlie tic behaviour, evidence is scarce and inconclusive. Deep brain stimulation (DBS) of the thalamic centromedian parafascicular complex (CMPf), an approved surgical interventive treatment for medical refractory Tourette syndrome, may reduce tics by affecting striatal dopamine release. Here, we use electrophysiology, electrochemistry, optogenetics, pharmacological treatments and behavioural measurements to mechanistically examine how thalamic DBS modulates synaptic and tonic dopamine activity in the dorsomedial striatum. Previous studies demonstrated focal disruption of GABAergic transmission in the dorsolateral striatum of rats led to repetitive motor tics recapitulating the major symptom of Tourette syndrome. We employed this model under light anaesthesia and found CMPf DBS evoked synaptic dopamine release and elevated tonic dopamine levels via striatal cholinergic interneurons while concomitantly reducing motor tic behaviour. The improvement in tic behaviour was found to be mediated by D2 receptor activation as blocking this receptor prevented the therapeutic response. Our results demonstrate that release of striatal dopamine mediates the therapeutic effects of CMPf DBS and points to striatal dopamine dysfunction as a driver for motor tics in the pathoneurophysiology of Tourette syndrome.

Serotonin plays a vital role in drug addiction. Here, using N-shaped fast-scan cyclic voltammetry, we demonstrated the effect of cocaine on the phasic release of serotonin at the nucleus accumbens core. To the best of our knowledge, this has not previously been elucidated. Our results not only reinforce the role of serotonin in the mechanism of action of cocaine but also help to fill a gap in our knowledge and provide a baseline for future studies in cocaine addiction.