Hand Dystonia after Focused Ultrasound Thalamotomy in Essential Tremor.

INTRODUCTION: Magnetic resonance guided focused ultrasound (MRgFUS) thalamotomy is an effective treatment for drug-resistant tremor. The most frequent side effects are ataxia, gait disturbance, paresthesias, dysgeusia, and hemiparesis. Here, we report the first case of thalamic hand dystonia rapidly occurring after MRgFUS thalamotomy of the ventral intermediate nucleus (V.im). CASE PRESENTATION: MRgFUS thalamotomy was performed in a 60-year-old left-handed patient for his disabling medically refractory essential tremor. The intervention resulted in a marked reduction of his action tremor. However, the patient developed an unvoluntary abnormal posture in his left hand a few days after the procedure with difficulty holding a cigarette between his fingers. Brain MRI revealed the expected MRgFUS lesion within the right V.im as well as an extension of the lesion anteriorly to the V.im in the ventro-oralis nucleus. Tractography showed that the lesion disrupted the dentato-rubro-thalamic tract as expected with a lesion suppressing tremor. However, the lesion also was interrupted fibers connecting to the superior frontal and pre-central cortices (primary motor cortex, premotor cortex, and supplementary area). We hypothesized that the interventional MRgFUS thalamotomy was slightly off target, which induced a dysfunction within the cortico-striato-thalamo-cortical network and the cerebello-thalamo-cortical pathway reaching a sufficient threshold of basal ganglia/cerebellum circuitry interference to induce dystonia. CONCLUSION: This rare side effect emphasizes the risk of imbalance within the dystonia network (i.e., basal ganglia-cerebello-thalamo-cortical circuit) secondary to V.im thalamotomy.

Electroencephalographic Abnormalities in a Patient Suffering from Long-Term Neuropsychological Complications following SARS-CoV-2 Infection.

Introduction: Emotional apathy has recently been identified as a common symptom of long COVID. While recent meta-analyses have demonstrated generalized EEG slowing with the emergence of delta rhythms in patients hospitalized for severe SARS-CoV-2 infection, no EEG study or dopamine transporter scintigraphy (DaTSCAN) has been performed in patients with long COVID presenting with apathy. The objective of this case report was to explore the pathophysiology of neuropsychological symptoms in long COVID. Case Presentation: A 47-year-old patient who developed a long COVID with prominent apathy following an initially clinically mild SARS-CoV-2 infection underwent neuropsychological assessment, cerebral MRI, DaTSCAN, and resting-state high-density EEG 7 months after SARS-CoV-2 infection. The EEG data were compared to those of 21 healthy participants. The patient presented with apathy, cognitive difficulties with dysexecutive syndrome, moderate attentional and verbal episodic memory disturbances, and resolution of premorbid mild gaming disorder, mild mood disturbances, and sleep disturbances. His MRI and DaTSCAN were unremarkable. EEG revealed a complex pattern of oscillatory abnormalities compared to the control group, with a strong increase in whole-scalp delta and beta band activity, as well as a decrease in alpha band activity. Overall, these effects were more prominent in the frontal-central-temporal region. Conclusion: These results suggest widespread changes in EEG oscillatory patterns in a patient with long COVID characterized by neuropsychological complications with prominent apathy. Despite the inherent limitations of a case report, these results suggest dysfunction in the cortical networks involved in motivation and emotion.

Successful MRI-Guided Focused Ultrasound Thalamotomy after Ipsilateral Gamma Knife Radiosurgery for Essential Tremor: A Case Report with Video.

We report the case of a 67-year-old left-handed female patient with disabling medically refractory essential tremor who underwent successful right-sided magnetic resonance-guided focused ultrasound (MRgFUS) of the ventral intermediate nucleus after ipsilateral gamma knife radiosurgery (GKRS) thalamotomy performed 3 years earlier. The GKRS had a partial effect on her postural tremor without side effects, but there was no reduction of her kinetic tremor or improvement in her quality of life (QoL). The patient subsequently underwent a MRgFUS thalamotomy, which induced an immediate and marked reduction in both the postural and kinetic tremor components, with minor complications (left upper lip hypesthesia, dysmetria in her left hand, and slight gait ataxia). The MRgFUS-induced lesion was centered more medially than the GKRS-induced lesion and extended more posteriorly and inferiorly. The MRgFUS-induced lesion interrupted remaining fibers of the dentatorubrothalamic tract (DRTT). The functional improvement 1-year post-MRgFUS was significant due to a marked reduction of the patient's kinetic tremor. The QoL score (Quality of Life in Essential Tremor) improved by 88% and her Clinical Rating Scale for Tremor left hand score by 62%. The side effects persisted but were minor, with no impact on her QoL. The explanation for the superior efficacy of MRgFUS compared to GKRS in our patient could be due to either a poor response to the GKRS or to a better localization of the MRgFUS lesion with a more extensive interruption of DRTT fibers. In conclusion, MRgFUS can be a valuable therapeutic option after unsatisfactory GKRS, especially because MRgFUS has immediate clinical effectiveness, allowing intra-procedural test lesions and possible readjustment of the target if necessary.

Validation of Lead-DBS ß-Oscillation Localization with Directional Electrodes.

In deep brain stimulation (DBS) studies in patients with Parkinson's disease, the Lead-DBS toolbox allows the reconstruction of the location of ß-oscillations in the subthalamic nucleus (STN) using Vercise Cartesia directional electrodes (Boston Scientific). The objective was to compare these probabilistic locations with those of intraoperative monopolar ß-oscillations computed from local field potentials (0.5-3 kHz) recorded by using shielded single wires and an extracranial shielded reference electrode. For each electrode contact, power spectral densities of the ß-band (13-31 Hz) were compared with those of all eight electrode contacts on the directional electrodes. The DBS Intrinsic Template AtLas (DISTAL), electrophysiological, and DBS target atlases of the Lead-DBS toolbox were applied to the reconstructed electrodes from preoperative MRI and postoperative CT. Thirty-six electrodes (20 patients: 7 females, 13 males; both STN electrodes for 16 of 20 patients; one single STN electrode for 4 of 20 patients) were analyzed. Stimulation sites both dorsal and/or lateral to the sensorimotor STN were the most efficient. In 33 out of 36 electrodes, at least one contact was measured with stronger ß-oscillations, including 23 electrodes running through or touching the ventral subpart of the ß-oscillations' probabilistic volume, while 10 did not touch it but were adjacent to this volume; in 3 out of 36 electrodes, no contact was found with ß-oscillations and all 3 were distant from this volume. Monopolar local field potentials confirmed the ventral subpart of the probabilistic ß-oscillations.

[Dementia with Lewy bodies: state of the art and perspectives for the clinician]. / Démence à corps de Lewy : état de l'art et perspectives pour le clinicien.

Dementia with Lewy bodies (DLB) is one of the most common causes of dementia, after Alzheimer's disease (AD) and vascular dementia. Its diagnosis remains a challenge for the clinician because of the variety of clinical presentations and comorbidities. The diagnosis is based on clinical criteria such as cognitive fluctuations, visual hallucinations, progressive cognitive impairment, Parkinsonian signs and REM sleep behavioral disorder. Although not specific, biomarkers are helpful for increasing the likelihood of LBD diagnosis and for differentiating LBD from other differential diagnoses such as Parkinson's disease with dementia and Alzheimer's disease. Clinicians should be aware of LBD clinical features and actively look for them in patients with cognitive symptoms, take into consideration the often-associated co-pathologies and to optimize patient's management.

La démence à corps de Lewy (DCL) est l'une des démences les plus fréquentes, après la maladie d'Alzheimer (MA) et la démence vasculaire. Son diagnostic est un défi pour le clinicien du fait de la variété des présentations cliniques et des comorbidités. Le diagnostic repose sur des critères cliniques comme des fluctuations cognitives, des hallucinations visuelles, des troubles cognitifs progressifs, des signes parkinsoniens et un trouble comportemental du sommeil paradoxal. L'utilisation des biomarqueurs, bien que non spécifiques, permet d'augmenter la probabilité de diagnostic de la DCL et de la différencier de la maladie de Parkinson avec démence et de la MA. De ce fait, devant tout sujet âgé avec trouble cognitif, une recherche des symptômes de la DCL est à réaliser en considérant aussi les traitements iatrogènes et les copathologies.

Oral Dysbiosis and Inflammation in Parkinson's Disease.

BACKGROUND: Oral microbiota has largely escaped attention in Parkinson's disease (PD), despite its pivotal role in maintaining oral and systemic health. OBJECTIVE: The aim of our study was to examine the composition of the oral microbiota and the degree of oral inflammation in PD. METHODS: Twenty PD patients were compared to 20 healthy controls. Neurological, periodontal and dental examinations were performed as well as dental scaling and gingival crevicular fluid sampling for cytokines measurement (interleukine (IL)-1ß, IL-6, IL-1 receptor antagonist (RA), interferon-γ and tumor necrosis factor (TNF)-α). Two months later, oral microbiota was sampled from saliva and subgingival dental plaque. A 16S rRNA gene amplicon sequencing was used to assess bacterial communities. RESULTS: PD patients were in the early and mid-stage phases of their disease (Hoehn & Yahr 2-2.5). Dental and periodontal parameters did not differ between groups. The levels of IL-1ß and IL-1RA were significantly increased in patients compared to controls with a trend for an increased level of TNF-α in patients. Both saliva and subgingival dental plaque microbiota differed between patients and controls. Streptococcus mutans, Kingella oralis, Actinomyces AFQC_s, Veillonella AFUJ_s, Scardovia, Lactobacillaceae, Negativicutes and Firmicutes were more abundant in patients, whereas Treponema KE332528_s, Lachnospiraceae AM420052_s, and phylum SR1 were less abundant. CONCLUSION: Our findings show that the oral microbiome is altered in early and mid-stage PD. Although PD patients had good dental and periodontal status, local inflammation was already present in the oral cavity. The relationship between oral dysbiosis, inflammation and the pathogenesis of PD requires further study.

Geospatial analysis of individual-based Parkinson's disease data supports a link with air pollution: A case-control study.

BACKGROUND: The etiology of Parkinson's disease (PD) remains unknown. To approach the issue of PD's risk factors from a new perspective, we hypothesized that coupling the geographic distribution of PD with spatial statistics may provide new insights into environmental epidemiology research. The aim of this case-control study was to examine the spatial dependence of PD prevalence in the Canton of Geneva, Switzerland (population = 474,211). METHODS: PD cases were identified through Geneva University Hospitals, private neurologists and nursing homes medical records (n = 1115). Controls derived from a population-based study (n = 12,614) and a comprehensive population census dataset (n = 237,771). All individuals were geographically localized based on their place of residence. Spatial Getis-Ord Gi* statistics were used to identify clusters of high versus low disease prevalence. Confounder-adjustment was performed for age, sex, nationality and income. Tukey's honestly significant difference was used to determine whether nitrogen dioxide and particulate matters PM10 concentrations were different within PD hotspots, coldspots or neutral areas. RESULTS: Confounder-adjustment greatly reduced greatly the spatial association. Characteristics of the geographic space influenced PD prevalence in 6% of patients. PD hotspots were concentrated in the urban centre. There was a significant difference in mean annual nitrogen dioxide and PM10 levels (+3.6 µg/m3 [p < 0.001] and +0.63 µg/m3 [p < 0.001] respectively) between PD hotspots and coldspots. CONCLUSION: PD prevalence exhibited a spatial dependence for a small but significant proportion of patients. A positive association was detected between PD clusters and air pollution. Our data emphasize the multifactorial nature of PD and support a link between PD and air pollution.

Embarrassment and Shame in People With Parkinson's Disease: A New Tool for Self-Assessment.

Shame and embarrassment related to Parkinson's disease (PD) are rarely addressed in clinical practice nor studied in neuroscience research, partly because no specific tool exists to detect them in PD. Objective: To develop a self-applied assessment tool of shame and embarrassment specifically related to PD or its treatment, to promptly identify the presence and severity of these two emotions in PD. Methods: Identification and selection of relevant items were obtained from the collection of PD patients' opinions during support groups and interviews. Several further items were added following a literature review. Subsequently, a two-phase pilot study was performed for identification of ambiguous items and omissions, and to obtain preliminary data on acceptability, reliability, validity and relevance of the new scale (SPARK). Results: A total of 105 PD patients were enrolled in the study. Embarrassment was reported in 85% of patients, while shame was present in 26%. Fifteen percent of patients did not describe any shame or embarrassment. On average, the intensity of these two emotions was low with a marked floor effect in SPARK items and subscales. However, SPARK total score inter-individual variability was important (range 1-84 out of 99). Acceptability and quality of data were satisfactory with no floor or ceiling effects (2.9% each) or missing data. Internal consistency (Cronbach's alpha) was 0.94 for total score and 0.73-0.87 for subscales. The scale correlated ≥0.60 with instruments measuring related constructs. Content validity was satisfactory. SPARK total score strongly correlated with impaired health-related quality of life (rS = 0.81), the propensity to feel embarrassed or ashamed (rS = 0.68 and 0.66, respectively), and anxiety (rS = 0.72) and depression (rS = 0.63) levels. Moderate to high correlations were observed between SPARK total score and apathy (rS = 0.46) and a more pronounced personality trait directed toward harm avoidance (rS = 0.46). No significant differences in SPARK scores were found by sex, education level, PD duration, Hoehn and Yahr stages or PD phenotype. Conclusion: Preliminary analysis of psychometric properties suggests that SPARK could be an acceptable and reliable instrument for assessing shame and embarrassment in PD. SPARK could help healthcare professionals to identify and characterize PD-induced shame and embarrassment.

Extrastriatal 123I-FP-CIT SPECT impairment in degenerative parkinsonisms.

INTRODUCTION: Neuropathological data and nuclear medicine imaging show extensive serotonergic impairment in Parkinson's disease (PD) and atypical parkinsonian syndromes (APS). The study aims at performing a case-controlled region-of-interest (ROI)-based analysis of 123I-N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl) nortropane (123I-FP-CIT) images to measure extrastriatal regional deficits in PD and APS, and assess their added diagnostic value in discriminating degenerative parkinsonisms from other conditions. METHODS: We included 157 patients with early degenerative parkinsonism (mean age 72.6 years, 44% female, mean disease duration at scan 1.6 years), i.e. PD (n = 59), multiple system atrophy parkinsonian variant (MSA-P, n = 17), progressive supranuclear palsy (PSP, n = 28), corticobasal syndrome (CBS, n = 19), dementia with Lewy bodies (DLB, n = 34) as well as 58 similarly-aged control participants. 123I-FP-CIT SPECT images were processed with statistical parametric mapping 12 (SPM12)-based PETPVE12 software and subjected to partial volume effect correction for ROI-based group comparisons. RESULTS: Relative to controls, all forms of degenerative parkinsonism showed decreased 123I-FP-CIT uptake in caudate nucleus, putamen but also pallidum and insula. In addition, a significant uptake reduction was observed in thalamus for MSA-P and PSP, in midbrain for PD and PSP, and in the amygdala for PSP (ANCOVA controlling for age, sex and antidepressant medication, all Bonferroni-corrected p < 0.007). Receiver-operating characteristics area-under-the-curve showed that adding extrastriatal evaluation led to higher accuracies in separating degenerative conditions from control participants (96.1% vs 94.9% with striatal ROIs only, p = 0.045). CONCLUSION: This study provides evidence of a major extrastriatal 123I-FP-CIT impairment, and therefore of an altered serotonergic transmission in PD and APS, confirming previous neuropathological and SERT imaging findings.

Modeling of Electric Fields in Individual Imaging Atlas for Capsular Threshold Prediction of Deep Brain Stimulation in Parkinson's Disease: A Pilot Study.

Background: Modeling of deep brain stimulation electric fields and anatomy-based software might improve post-operative management of patients with Parkinson's disease (PD) who have benefitted from subthalamic nucleus deep brain stimulation (STN-DBS). Objective: We compared clinical and software-guided determination of the thresholds for current diffusion to the pyramidal tract, the most frequent limiting side effect in post-operative management of STN-DBS PD patients. Methods: We assessed monopolar reviews in 16 consecutive STN-DBS PD patients and retrospectively compared clinical capsular thresholds, which had been assessed according to standard clinical practice, to those predicted by volume of tissue activated (VTA) model software. All the modeling steps were performed blinded from patients' clinical evaluations. Results: At the group level, we found a significant correlation (p = 0.0001) when performing statistical analysis on the z-scored capsular thresholds, but with a low regression coefficient (r = 0.2445). When considering intra-patient analysis, we found significant correlations (p < 0.05) between capsular threshold as modeled with the software and capsular threshold as determined clinically in five patients (31.2%). Conclusions: In this pilot study, the VTA model software was of limited assistance in identifying capsular thresholds for the whole cohort due to a large inter-patient variability. Clinical testing remains the gold standard in selecting stimulation parameters for STN-DBS in PD.

Dyskinesia-inducing lead contacts optimize outcome of subthalamic stimulation in Parkinson's disease.

BACKGROUND: Acute dyskinesias elicited by STN-DBS, here referred to as stimulation-induced dyskinesias, predict optimal clinical outcome in PD. However, it remains elusive whether stimulation-induced dyskinesias can guide DBS programming. OBJECTIVES: Here, we characterized stimulation-induced dyskinesias clinically and anatomically. We then tested whether dyskinesia-inducing contacts could be effectively programmed using independent current source technology. METHODS: We characterized stimulation-induced dyskinesias with directional and ring stimulation retrospectively in 20 patients. We then localized dyskinesia-inducing contacts by imaging coregistration and eventually programmed those contacts. RESULTS: We elicited dyskinesias in half of our patients. Dyskinesia-inducing contacts were mainly directional and were all located ventrally within the dorsolateral motor STN. When these dyskinesia-inducing contacts were programmed using independent current source technology, dyskinesia disappeared and robust antibradykinetic effects were obtained. CONCLUSION: We confirm that stimulation-induced dyskinesias are helpful clinical observations, which may guide programming of directional STN-DBS in PD. © 2019 International Parkinson and Movement Disorder Society.

Classification of degenerative parkinsonism subtypes by support-vector-machine analysis and striatal 123I-FP-CIT indices.

OBJECTIVES: To provide an automated classification method for degenerative parkinsonian syndromes (PS) based on semiquantitative 123I-FP-CIT SPECT striatal indices and support-vector-machine (SVM) analysis. METHODS: 123I-FP-CIT SPECT was performed at a single-center level on 370 individuals with PS, including 280 patients with Parkinson's disease (PD), 21 with multiple system atrophy-parkinsonian type (MSA-P), 41 with progressive supranuclear palsy (PSP) and 28 with corticobasal syndrome (CBS) (mean age 70.3 years, 47% female, mean disease duration at scan 1.4 year), as well as 208 age- and gender-matched control subjects. Striatal volumes-of-interest (VOIs) uptake, VOIs asymmetry indices (AIs) and caudate/putamen (C/P) ratio were used as input for SVM individual classification using fivefold cross-validation. RESULTS: Univariate analyses showed significantly lower VOIs uptake, higher striatal AI and C/P ratio for each PS in comparison to controls (all p < 0.001). Among PS, higher degree of striatal impairment was observed in MSA-P and PSP, while CBS showed moderate uptake reduction and higher AI. Binary SVM classification showed 92.9% accuracy in distinguishing PS from controls. Classification based on each binary combination of PS ranged 62.9-83.7% accuracy with the most satisfactory results when separating CBS from the other PS. Sensitivity and specificity values were high and balanced ranging from 60 to 80% for all analyses with > 70% accuracy. Overall, striatal AI and C/P ratio on the more affected side had the highest weighting factors. CONCLUSION: Semiquantitative 123I-FP-CIT SPECT striatal evaluation combined with SVM represents a promising approach to disentangle PD from non-degenerative conditions and from atypical PS at the early stage.

Shame in Parkinson'S Disease: A Review.

Shame is a self-conscious emotion marked by an intensely negative self-evaluation. It is exhibited by an individual upon realizing that she/he has violated an important (usually social) norm. Shame can be a source of emotional distress leading to social withdrawal and depression, with a significant negative impact on quality of life. In Parkinson's disease (PD), shame is rarely addressed. Based on reports of persons affected with Parkinson's disease (PwP) as well as a literature review, this article describes PD-related shame. PD-related shame may emerge from motor and non-motor symptoms, from self-perception of inadequacy due to loss of autonomy and need for help, or from perceived deterioration of body image. The neurobiology of shame delineates neuronal networks involved in cognitive and emotions regulation, self-representation and representation of the others mental states. Although this hypothesis remains to be demonstrated, these substrates could be modulated, at least partially, by dopaminergic depletion related to PD, which may open a window for pharmacotherapy. Owing to the negative impact that shame can produce, shame should be actively explored and addressed in the individual PwP. Teaching PwP how to develop resilience to shame may be a useful strategy in preventing the vicious circle of shame. The paucity of existing data on prevalence and management of PD-specific shame contrasts with the manifold reported situations inducing suffering from shame. There is a crucial need for further investigations of shame in PD and the development of interventions to reduce its impact on PwP's quality of life.

What Is the Best Electrophysiologic Marker of the Outcome of Subthalamic Nucleus Stimulation in Parkinson Disease?

OBJECTIVE: Deep brain stimulation of the subthalamic nucleus (STN) is advocated in patients with advanced Parkinson disease. Intraoperative microelectrode recordings (MER) and stimulation or imaging are applied to confirm electrode targeting. The study objective was to evaluate which intraoperative electrophysiologic marker, MER, stimulation, or local field potentials (LFP) was the most predictive of the clinical efficacy. METHODS: Efficacy was determined with lateralized motor scores of Movement Disorders Society-Unified Parkinson's Disease Rating Scale in 36 patients (OFF-drug/ON-stimulation 1 year after surgery vs. OFF-drug before surgery). Trajectory lengths in STN were determined from MER. Stimulation was increased up to the thresholds of first decrease, of complete suppression of rigidity, and of excitation of pyramidal motor tract. ß oscillations (11-31 Hz) were computed from LFP of the electrode macrocontact. Univariate and multivariate analyses were computed. RESULTS: Motor improvements were linked to trajectory lengths in STN (R2 = 0.17; P > 0.005). No significant relationship was found for thresholds of first decrease or suppression in rigidity or for motor tract excitation (R2 < 0.03, P > 0.05). Motor improvements were most linked to ß oscillation increases (R2 = 0.57, P < 0.005, linear regression; R2 = 0.84, P < 0.0001, post hoc sigmoid regression). ß oscillations appeared more predictive than length (ß: t = 5.4, P < 0.001; length: t = 2.70, P < 0.03). Improvements were also slightly predicted by preoperative scores (R2 = 0.13; P < 0.005). CONCLUSIONS: Motor improvements emerged as most related to ß oscillations, before trajectory length within the STN, whereas stimulation thresholds of rigidity or of motor tract excitation failed to show any relationship. The study encourages LFP measurement to confirm STN electrode location.

Hyperdopaminergic behavioral spectrum in Parkinson's disease: A review.

Impulse control disorders (ICDs) and other related behaviors, such as punding and dopamine dysregulation syndrome, are frequent yet underrecognized non-motor complications of dopamine replacement therapy (DRT) in Parkinson's disease (PD); they can also have a major negative impact on quality of life. They result from complex interactions between a given individual's predispositions, non-physiological dopaminergic stimulation and PD pathology. Also, sensitization of the mesocorticolimbic pathway, reflected by the psychotropic effects of dopaminergic treatment, plays a crucial role in the emergence of these addictive behaviors. While early detection of changes in behavior, less use of dopamine agonists (DA) that have a relative selectivity for mesocorticolimbic dopamine receptors, and fractionation of levodopa dosages to avoid non-physiological pulsatile stimulation of dopamine receptors are key strategies in the management of this hyperdopaminergic behavioral spectrum, other complementary approaches are also addressed in this review.

[Advanced Parkinson's disease : indication for complex treatments]. / Maladie de Parkinson au stade avancé : indication aux traitements complexes.

Advanced Parkinson's disease (PD) is characterized by severe motor and non-motor complications that negatively impact on patients' autonomy and health-related quality of life. In early disease, the therapeutic strategy consists of gradual increase in dopaminergic treatment and levodopa dose fragmentation. In more advanced stages, this approach becomes insufficient and three therapeutic options can be considered: deep brain stimulation (DBS), continuous subcutaneous apomorphine infusion, and continuous levodopa/carbidopa intestinal gel infusion.

La maladie de Parkinson (MP) avancée est caractérisée par la présence de complications motrices et non motrices qui ont un impact significatif sur l'autonomie et la qualité de vie des patients. La stratégie thérapeutique consiste à fractionner le traitement dopaminergique, à recourir aux formes à libération prolongée, et aux inhibiteurs des enzymes de dégradation de la dopamine. Lorsque ces mesures sont insuffisantes, trois options thérapeutiques plus invasives peuvent être envisagées : la stimulation cérébrale profonde, la perfusion sous-cutanée continue d'apomorphine et l'administration intrajéjunale de gel de lévodopa/carbidopa. L'objectif de cet article est de décrire les indications, bénéfices et effets secondaires potentiels de ces traitements dits « complexes ¼.

[Movement disorders emergencies]. / Mouvements anormaux aux urgences.

Unlike most basal ganglia disorders, which usually progress slowly and relentlessly, a number of movement disorders may develop as acute or subacute conditions. Their occurrence commonly prompts patients to rush into the emergency room. A proper diagnosis is not always straightforward and requires a detailed analysis of the movement disorder phenomenology and a thorough medication screening, as many of these acute situations may be iatrogenic and drug-related. An accurate identification of the problem may enable an effective management and an appropriate therapy. This article is an overview of three distinct movement disorder emergencies, namely acute dystonia, acute chorea, and acute complications that can be observed in Parkinson's disease. Each topic is illustrated with a case report.

Contrairement à la plupart des affections des ganglions de la base, qui évoluent généralement sur un mode lentement progressif, certains mouvements anormaux peuvent se développer sur un mode aigu ou subaigu, amenant les patients à consulter en urgence. Le diagnostic est souvent délicat. Il repose sur une analyse détaillée de la phénoménologie et une anamnèse médicamenteuse fouillée, dans la mesure où ces situations sont volontiers iatrogènes. Une identification correcte du problème permet souvent une thérapeutique efficace. Le présent article propose une mise au point de trois problématiques de ce type, à savoir la dystonie aiguë, la chorée aiguë et les complications aiguës que l'on peut observer dans la maladie de Parkinson. Chaque sujet est illustré par un cas clinique.

Descriptive epidemiology of parkinsonism in the Canton of Geneva, Switzerland.

OBJECTIVES: A large descriptive cross-sectional population-based prevalence study as well as a retrospective incidence study were undertaken to ascertain the frequency of Parkinson's Disease (PD) and other types of degenerative and non-degenerative parkinsonism in the Canton of Geneva, Switzerland. METHODS: An extensive case-finding approach including records from public hospitals, private neurologists and nursing homes was utilized. All patients with a diagnosis of parkinsonism established between 2003 and 2012 were included. Diagnosis of parkinsonism was ascertained by a movement disorders specialist, based on published and validated consensus diagnostic criteria. RESULTS: A total of 1235 living patients with parkinsonism were identified, from which 80% presented with a degenerative form and 20% with a non-degenerative form of parkinsonism. Among the former, PD was the most frequent diagnosis (81%, age-adjusted prevalence: 183/105 inhabitants, age-adjusted average annual incidence: 20/105/year) followed by dementia with Lewy bodies (9%), progressive supranuclear palsy (3.9%), multisystem atrophy (1.9%) and corticobasal syndrome (1.4%). Among non-degenerative parkinsonism, drug-induced parkinsonism was the most frequent diagnosis (43.4%), followed by vascular parkinsonism (37%), normal pressure hydrocephalus (5.1%) and parkinsonism in the context of a psychiatric disorder or functional parkinsonism (3.8%). Crude, age-, sex-specific and age-adjusted prevalence and incidence of all types of parkinsonism are detailed for each diagnosis. CONCLUSION: This is the first Swiss population-based epidemiological study of PD and parkinsonism. It provides an extensive overview of the prevalence and incidence of degenerative and non-degenerative forms of parkinsonism. These data may assist clinicians with their clinical workup.

Prevalence of functional (psychogenic) parkinsonism in two Swiss movement disorders clinics and review of the literature.

BACKGROUND: Functional parkinsonism (FP) is considered rare but no studies have looked at its frequency. Case series have described high rates of comorbidity with Parkinson's disease (PD), suggesting a possible association between these conditions. OBJECTIVES: To study the prevalence, epidemiology and clinical features of FP and its association with PD. METHODS: We conducted a cross-sectional population-based prevalence study as well as a chart review of cases who received a diagnosis of FP over a 10-year-period in two movement disorder clinics in Switzerland. Epidemiological data regarding FP features were collected. The co-occurrence of PD, psychiatric disorders and other functional disorders were recorded. Clinical differences between FP and FP+PD groups are presented and discussed in light of a literature review. RESULTS: The crude prevalence of FP was 0.64 per 100,000 in our population. FP represented 0.24% of patients with parkinsonism. Among 12 FP cases, female gender predominance (87%), mean age of onset of 45.5(±13.3 Standard deviation SD) years and prolonged diagnostic delay (mean 59±75 SD months) was found. Six patients had an additional diagnosis of PD, 83% of depression and 66% of other functional neurological disorder. In four patients with FP+PD, FP preceded PD by 6 to 56months. CONCLUSIONS: These results suggest that FP should be considered in the differential diagnosis of patients presenting with parkinsonism. The high rate of co-occurrence with PD emphasizes the importance of long-term follow up of these patients. The observation that FP often precedes PD should be verified in prospective studies.

Short pulse width in subthalamic stimulation in Parkinson's disease: a randomized, double-blind study.

BACKGROUND: We investigated the acute effect of short pulse widths on the therapeutic window in subthalamic nucleus deep brain stimulation in Parkinson's disease. METHODS: We assessed 10 PD patients with STN-DBS at a 60-µs pulse width. We randomly and double-blindedly applied 10- to 50-µs pulse widths. The principal outcome was the therapeutic window (difference between the amplitude thresholds for visible muscle contraction and for best rigidity control). The secondary outcome was the charge per pulse (which reflects the efficiency of the stimulation) needed to control rigidity. Two-way analysis of variance and pairwise t tests were applied. RESULTS: The therapeutic window widened when the pulse width shortened (r = -0.45; P < 0.001), and charge per pulse was reduced (P < 0.05). CONCLUSIONS: This randomized, double-blind study showed that shorter pulse widths widen the therapeutic window of STN-DBS in PD without increasing the electrical charge required to obtain the same acute clinical benefit. © 2017 International Parkinson and Movement Disorder Society.