We report the first post-mortem analysis of two patients with Parkinson's disease who received fetal midbrain transplants as a cell suspension in the striatum, and in one case also in the substantia nigra. These patients had a favourable clinical evolution and positive 18F-fluorodopa PET scans and did not develop motor complications. The surviving transplanted dopamine neurons were positively identified with phenotypic markers of normal control human substantia nigra (n = 3), such as tyrosine hydroxylase, G-protein-coupled inward rectifying current potassium channel type 2 (Girk2) and calbindin. The grafts restored the cell type that provides specific dopaminergic innervation to the most affected striatal regions in the parkinsonian brain. Such transplants were able to densely reinnervate the host putamen with new dopamine fibres. The patients received only 6 months of standard immune suppression, yet by post-mortem analysis 3-4 years after surgery the transplants appeared only mildly immunogenic to the host brain, by analysis of microglial CD45 and CD68 markers. This study demonstrates that, using these methods, dopamine neuronal replacement cell therapy can be beneficial for patients with advanced disease, and that changing technical approaches could have a favourable impact on efficacy and adverse events following neural transplantation.

Postmortem analysis of five subjects with Parkinson's disease9-14 years after transplantation of fetal midbrain cell suspensions revealed surviving grafts that included dopamine and serotonin neurons without pathology. These findings are important for the understanding of the etiopathogenesis of midbrain dopamine neuron degeneration and future use of cell replacement therapies.Despite indirect evidence of long-term survival of fetal midbrain dopamine cell suspensions in people with Parkinson's disease 1 , the question remains whether grafted neurons are affected by pathogenic factors intrinsic to the parkinsonian brain.Prominent neuropathological features of Parkinson's disease include dopaminergic neuron loss in the substantia nigra, the presence of dystrophic neurites (Lewy neurites) 2 and the presence of Lewy bodies 3,4 . Ultimately, the durability of transplanted fetal ventral midbrain neurons in therapeutic approaches relies on their resistance to these neurodegenerative processes. Because many aspects of these processes remain unknown, it is important to understand the effects of neurodegeneration in the parkinsonian striatum upon transplanted fetal dopamine neurons. We report histopathological findings in the brains of three subjects (referred to as subjects 4, 5 and 6) with advanced idiopathic Parkinson's disease who had received intracerebral transplantation

Background: Spatial 3-dimensional understanding of the brain is essential to learning neuroanatomy, and 3-dimensional learning techniques have been proposed as tools to enhance neuroanatomy training. The aim of this study was to examine the impact of immersive virtual-reality neuroanatomy training and compare it to traditional paper-based methods. Methods:In this randomized controlled study, participants consisted of first-or second-year medical students from the University of Saskatchewan recruited via email and posters displayed throughout the medical school. Participants were randomly assigned to the virtual-reality group or the paper-based group and studied the spatial relations between neural structures for 12 minutes after performing a neuroanatomy baseline test, with both test and control questions. A postintervention test was administered immediately after the study period and 5-9 days later. Satisfaction measures were obtained. Results:Of the 66 participants randomly assigned to the study groups, 64 were included in the final analysis, 31 in the virtual-reality group and 33 in the paper-based group. The 2 groups performed comparably on the baseline questions and showed significant performance improvement on the test questions following study. There were no significant differences between groups for the control questions, the postintervention test questions or the 7-day postintervention test questions. Satisfaction survey results indicated that neurophobia was decreased. Interpretation:Results from this study provide evidence that training in neuroanatomy in an immersive and interactive virtual-reality environment may be an effective neuroanatomy learning tool that warrants further study. They also suggest that integration of virtualreality into neuroanatomy training may improve knowledge retention, increase study motivation and decrease neurophobia. Abstract Research E104CMAJ OPEN, 6(1)

Summary To determine the long-term health and function of transplanted dopamine neurons in Parkinson’s disease (PD) patients, the expression of dopamine transporters (DAT) and mitochondrial morphology was examined in human fetal midbrain cellular transplants. DAT was robustly expressed in transplanted dopamine neuron terminals in the reinnervated host putamen and caudate, for at least 14 years after transplantation. The transplanted dopamine neurons showed a healthy and non-atrophied morphology at all time points. Labeling of the mitochondrial outer membrane protein Tom20 and alpha-synuclein showed typical cellular pathology in the patients’ own substantia nigra, which was not observed in transplanted dopamine neurons. These results show that the vast majority of transplanted neurons remain healthy long-term in PD patients, consistent with the clinically maintained function of fetal dopamine neuron transplants for up to 15–18 years in patients. These findings are critically important for the rational development of stem cell-based dopamine neuronal replacement therapies for PD.

The main neural transplantation strategy in Parkinson disease (PD) has been focused on reinnervating the striatum. The clinical results reported in patients who receive transplants have been limited and do not justify the use of neural transplantation as a routine therapeutic procedure for PD. Identifying the optimal target for transplantation may be one of the critical factors for optimizing clinical outcomes. Evidence from preclinical studies indicates that simultaneous intrastriatal and intranigral grafts (double grafts) may produce a more complete functional recovery. The authors report the clinical and positron emission tomography (PET) scanning results in three patients enrolled in a safety and feasibility pilot study who received double grafts and who have been followed for up to 13 months posttransplantation. Patients included in the study had idiopathic PD. All patients underwent detailed assessments before and after surgery, in accordance with the Core Assessment Program for Intracerebral Transplantation. The patients received implants of fetal mesencephalic cell suspensions in the putamen and substantia nigra (SN) bilaterally. There were no intraoperative or perioperative complications. Follow-up PET scans demonstrated an increase in the mean fluorodopa uptake constant values in the putamen and SN 12 months postsurgery. Improvements were also noted in the total Unified Parkinson's Disease Rating Scale, Hoehn and Yahr, Schwab and England, and pronation/supination scores after transplantation. The authors demonstrate the feasibility of reinnervating the SN and striatum by using a double transplant strategy in humans.

During the last decade many new options have become available for the surgical treatment of movement disorders. The development of new technologies for implanting chronic stimulating electrodes has made deep brain stimulation (DBS) a viable option to surgical lesioning. Unlike lesions which are permanent, DBS may be reversible and titratable. Deep brain stimulation has been demonstrated to be very effective and is increasingly used worldwide for the treatment of Parkinson's disease, dystonia, tremor and pain. [1][2][3][4][5] As with any implanted system, however, DBS introduces a new series of problems ABSTRACT: Background: Deep brain stimulation (DBS) is used increasingly worldwide for the treatment of Parkinson's disease, dystonia, tremor and pain. As with any implanted system, however, DBS introduces a new series of problems related to its hardware. Infection, malfunction and lead migration or fracture may increase patient morbidity and should be considered when evaluating the risk/benefit ratio of this therapy. This work highlights several factors felt to increase DBS hardware complications. Methods: The authors undertook a prospective analysis of their patients receiving this therapy in two Canadian centres, over a four-year period. Results: One hundred and forty-four patients received 204 permanent electrode implants. The average follow-up duration was 24 months. Complications related to the DBS hardware were seen in 11 patients (7.6%). There were two lead fractures (1.4%) and nine infections (6.2%) including two erosions (1.4%). There was a significantly greater risk of infection in patients who underwent staged procedures with externalization. In patients with straight scalp incisions, the rate of infection was higher than that seen with curved incisions. Conclusion: Hardware complications were not common. A period of externalization of the electrodes for a stimulation trial was associated with an increased infection rate. It is also possible that a straight scalp incision instead of curvilinear incision may lead to an increase in the rate of infection. With a clear understanding of the accepted DBS device indications and their potential complications, patients may make a truly informed decision about DBS technology.RÉSUMÉ: Réduire les complications dues à l'appareillage dans la stimulation cérébrale profonde. Introduction: La stimulation cérébrale profonde (SCP) est de plus en plus utilisée à travers le monde dans le traitement de la maladie de Parkinson, de la dystonie, du tremblement et de la douleur. Comme dans tout système comportant un implant, la SCP donne lieu à une nouvelle problématique reliée à l'appareillage utilisé. L'infection, le mauvais fonctionnement et le déplacement des électrodes ou leur fracture peut augmenter la morbidité. On devrait tenir compte de ces facteurs quand on évalue le rapport risques/bénéfices de ce traitement. Cette étude souligne plusieurs facteurs qui augmentent les complications de la SCP dues à l'appareillage. Méthodes: Les auteurs ont effectué une analyse prospect...

ABSTRACT

A telerobotic ultrasound system is feasible for performing abdominal ultrasound examinations at a distant location with minimal training and setup requirements and a moderate learning curve. Telerobotic sonography (robotic telesonography) may open up the possibility of remote ultrasound clinics for communities that lack skilled sonographers and radiologists, thereby improving access to care.