Search

Background: GBA variants increase the risk of developing Parkinson disease (PD) and influence its outcome. Deep brain stimulation (DBS) is a recognised therapeutic option for advanced PD. Data on DBS long-term outcome in GBA carriers are scarce., Objective: To elucidate the impact of GBA variants on long-term DBS outcome in a large Italian cohort., Methods: We retrospectively recruited a multicentric Italian DBS-PD cohort and assessed: (1) GBA prevalence; (2) pre-DBS clinical features; and (3) outcomes of motor, cognitive and other non-motor features up to 5 years post-DBS., Results: We included 365 patients with PD, of whom 73 (20%) carried GBA variants. 5-year follow-up data were available for 173 PD, including 32 mutated subjects. GBA-PD had an earlier onset and were younger at DBS than non-GBA-PD. They also had shorter disease duration, higher occurrence of dyskinesias and orthostatic hypotension symptoms.At post-DBS, both groups showed marked motor improvement, a significant reduction of fluctuations, dyskinesias and impulsive-compulsive disorders (ICD) and low occurrence of most complications. Only cognitive scores worsened significantly faster in GBA-PD after 3 years. Overt dementia was diagnosed in 11% non-GBA-PD and 25% GBA-PD at 5-year follow-up., Conclusions: Evaluation of long-term impact of GBA variants in a large Italian DBS-PD cohort supported the role of DBS surgery as a valid therapeutic strategy in GBA-PD, with long-term benefit on motor performance and ICD. Despite the selective worsening of cognitive scores since 3 years post-DBS, the majority of GBA-PD had not developed dementia at 5-year follow-up., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Deep brain stimulation (DBS) is effective for some neurological and psychiatric conditions. Idiopathic delayed-onset edema (IDE) surrounding the leads has been anecdotally reported. The etiology, predisposing factors and prognosis of this complication are unknown. We present a multicenter case series of patients with IDE, and a systematic literature review, aimed at defining the pathophysiology and identifying appropriate treatment strategies., Methods: IDE was defined as edema along the DBS lead, occurring ≥72 h postoperatively, in absence of trauma, vascular events or infection. Information on patients with IDE was collected in a standardized way. A systematic search was performed in Pubmed., Results: Twelve new patients presenting with 14 episodes of IDE are described. From the literature, 38 patients were identified. No common surgical aspects or patient-related factors were identified as risk predictors for the onset of IDE. Symptoms included deterioration of the stimulation effect, seizures and focal neurological signs. Although the condition is self-limiting, with symptoms resolution in 28.5 days on average, three patients underwent surgical revision and seven received antibiotics., Conclusions: IDE is a rare complication of DBS procedures, presenting from few days to months after surgery. Symptoms can be mild and not-specific, and the condition is self-limiting. The diagnosis of IDE is made after exclusion of vascular events or infections. The pathophysiology is still unexplained. The recognition of this complication can help avoiding unnecessary surgical procedures (system explantation) and antibiotic treatment., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Knowledge on dystonia has greatly improved recently, because of a renewed effort in understanding its cause, pathophysiology, and clinical characterization. Different drug classes traditionally have been used for the symptomatic treatment of dystonia, more recently surpassed by the introduction of botulinum neurotoxins and deep brain stimulation. No curative or disease-modifying treatments are available. Recent knowledge regarding the pathophysiology of inherited dystonias is highlighting new potential treatment strategies. We review therapeutic advances in dystonia that have been published over the last 3 years, particularly regarding oral medications, local injections of botulinum neurotoxins, deep brain stimulation, and transcranial or epidural brain stimulations. We discuss evidence of efficacy, highlight recent advances, and focus on key areas under development., (© 2015 International Parkinson and Movement Disorder Society.)

Motor complications in Parkinson's disease (PD) result from the short half-life and irregular plasma fluctuations of oral levodopa. When strategies of providing more continuous dopaminergic stimulation by adjusting oral medication fail, patients may be candidates for one of three device-aided therapies: deep brain stimulation (DBS), continuous subcutaneous apomorphine infusion, or continuous duodenal/jejunal levodopa/carbidopa pump infusion (DLI). These therapies differ in their invasiveness, side-effect profile, and the need for nursing care. So far, very few comparative studies have evaluated the efficacy of the three device-aided therapies for specific motor problems in advanced PD. As a result, neurologists currently lack guidance as to which therapy could be most appropriate for a particular PD patient. A group of experts knowledgeable in all three therapies reviewed the currently available literature for each treatment and identified variables of clinical relevance for choosing one of the three options such as type of motor problems, age, and cognitive and psychiatric status. For each scenario, pragmatic and (if available) evidence-based recommendations are provided as to which patients could be candidates for either DBS, DLI, or subcutaneous apomorphine.

Deep brain stimulation (DBS) extends the treatment of some severe neurological diseases beyond pharmacological and conservative therapy. Our experience extends the field of DBS beyond the treatment of Parkinson disease and dystonia, including several other diseases such as cluster headache and disruptive behavior. Since 1993, at the Istituto Nazionale Neurologico "Carlo Besta" in Milan, 580 deep brain electrodes were implanted in 332 patients. The DBS targets include Stn, GPi, Voa, Vop, Vim, CM-pf, pHyp, cZi, Nacc, IC, PPN, and Brodmann areas 24 and 25. Three hundred patients are still available for follow-up and therapeutic considerations. DBS gave a new therapeutic chance to these patients affected by severe neurological diseases and in some cases controlled life-threatening pathological conditions, which would otherwise result in the death of the patient such as in status dystonicus, status epilepticus and post-stroke hemiballismus. The balance of DBS in severe neurological disease is strongly positive even if further investigations and studies are needed to search for new applications and refine the selection criteria for the actual indications.

Unlabelled: An impairment for verbs has been described in patients with Parkinson's disease (PD), suggesting that a disruption of frontal-subcortical circuits may result in dysfunction of the neural systems involved in action-verb processing. A previous study suggested that deep brain stimulation (DBS) of the subthalamic nucleus (STN) during verb generation may affect the ability to select from many competing lexical alternatives. In this study, 12 PD patients who had undergone bilateral STN DBS and completed an 8-year follow-up and 14 matched normal controls were administered action and object naming tasks and verb and noun reading tasks. Their responses were recorded using a microphone, resulting in a signal that marked the onset of the verbal response and allowed to measure response times (RTs). Accuracy was scored manually., Results: Overall performance in naming (independently of stimulation): In naming task controls were faster and more accurate than PD patients. In both groups, performance (accuracy and RTs) was worse on action naming than object naming. PD patients were significantly slower than controls in naming actions. Effect of stimulation: Compared with the OFF stimulation condition, in ON stimulation condition PD patients showed improved performance on object and action naming tasks (increased accuracy, faster RTs), with a decreased number of semantic errors. Some evidence also emerged that action naming in the ON stimulation condition improved more than object naming. On noun and verb reading tasks, although accuracy was at ceiling in both groups and no significant difference was observed in RTs for nouns and verbs, PD patients were slower than controls., Conclusions: Our findings suggest that STN DBS may improve lexical search in PD patients. We hypothesize that STN stimulation may facilitate the motor components involved in naming and reading tasks (increased speed of speech onset), resulting in shorter RTs in both naming and reading and, to some extent, in increased accuracy in naming due to fewer omissions (no response within the 7500 ms time limit). However, to account for greater accuracy in naming due to decreased number of semantic errors in the ON stimulation condition, we hypothesize that STN stimulation restores the activity of the corticostriatal circuits involved in selection processes of a target word among different alternatives., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Deep brain stimulation (DBS) is an established procedure for the symptomatic treatment of Parkinson's disease. Several deep brain nuclei have been stimulated, producing a wide range of effects on the motor and non-motor symptoms of Parkinson's disease. Long-term, high-quality evidence is available for stimulation of the subthalamic nucleus and globus pallidus internus, both of which uniformly improve motor features, and for stimulation of the thalamic ventralis intermedius, which improves tremor. Short-term data are available for stimulation of other deep brain targets, such as the pedunculopontine nucleus and the centremedian/parafascicular thalamic complex. Some non-motor symptoms improve after DBS, partly because of motor benefit or reduction of drug treatment, and partly as a direct effect of stimulation. More evidence on the effects of DBS on non-motor symptoms is needed and specifically designed studies are warranted., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate the efficacy and safety of epidural premotor stimulation in patients with primary focal dystonia. Seven patients were selected: 6 had cervical dystonia and 1 had right upper limb dystonia. In 2 patients, sustained muscle contractions led to a prevalently fixed head posture. Patients with cervical dystonia received a bilateral implant, whereas the patient with hand dystonia received a unilateral implant. Neurological and neuropsychological evaluations were performed before surgery (baseline), and 1, 3, 6, and 12 months afterward. The Burke-Fahn-Marsden scale (BFMS) and the Toronto Western spasmodic torticollis rating scale (TWSTRS) were administered at the same time points. Patients underwent resting (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scans, before and 12 months after surgery. No adverse events occurred. An overall improvement was observed on the BFMS and TWSTRS after surgery. Patients with prevalently fixed cervical dystonia had a reduced benefit. Presurgical neuroimaging revealed a significant bilateral metabolic increase in the sensorimotor areas, which was reduced after surgery., (Copyright © 2012 Movement Disorder Society.)

The links between Stn DBS and advanced Parkinson disease, and between GPi DBS and dystonia are nearly universally accepted by the neurologists and neurosurgeons. Nevertheless, in some conditions, targets such as the ventral thalamus and the Zona Incerta may be considered to optimize the results and avoid the side effects. Positive and negative aspects of current DBS treatments justify the research of new targets, new stimulation programs and new hardware. Since 1993, at the Istituto Nazionale Neurologico "Carlo Besta" in Milan, 580 deep brain electrodes were implanted in 332 patients. 276 patients were affected by movement disorders. The DBS targets included Stn, GPi, Voa, Vop, Vim, CM-pf, cZi, IC. The long-term follow-up is reported and related to the chosen target. DBS gave a new therapeutic option to patients affected by severe movement disorders, and in some cases resolved life-threatening pathological conditions that would otherwise result in the death of the patient, such as in status dystonicus, and post-stroke hemiballismus. Nevertheless, the potential occurrence of severe complications still limit a wider use of DBS. At today, the use of DBS in severe movement disorders is strongly positive even if further investigations and studies are needed to unveil potential new applications, and to refine the selection criteria for the actual indications and targets. The experience of different targets may be useful to guide and tailor the target choice to the individual clinical condition.

When considering a patient with dystonia for deep brain stimulation (DBS) surgery several factors need to be considered. Level B evidence has shown that all motor features and associated pain in primary generalized and segmental dystonia are potentially responsive to globus pallidus internus (GPi) DBS. However, improvements in clinical series of ≥ 90% may reflect methods that need improvement, and larger prospective studies are needed to address these factors. Nevertheless, to date the selection criteria for DBS-specifically in terms of patient features (severity and nature of symptoms, age, time of evolution, or any other demographic or disease aspects)--have not been assessed in a systematic fashion. In general, dystonia patients are not considered for DBS unless medical therapies have been previously and extensively tested. The vast majority of reported patients have had DBS surgery when the disease was provoking important disability, with loss of independence and impaired quality of life. There does not appear to be an upper age limit or a minimum age limit, although there are no published data regarding the outcome of GPi DBS for dystonia in children younger than 7 years of age. There is currently no enough evidence to prove that subjects with primary--generalized dystonia who undergo DBS at an early age and sooner rather than later after disease onset may gain more benefit from DBS than those undergoing DBS after the development of fixed skeletal deformities. There is no enough evidence to refuse or support consideration of DBS in patients with previous ablative procedures., (Copyright © 2011 Movement Disorder Society.)

Background: The preoperative evaluation in dystonia aims at characterizing the severity and topography of motor symptoms in patients, who have previously been selected for deep brain stimulation (DBS)., Methods: The literature search was performed using PubMed, CINAHL, and the Cochrane Collaborative databases., Results: Commonly used scales for clinical assessment are the Burke-Fahn-Marsden dystonia rating scale for generalized dystonia and the Toronto Western Spasmodic Torticollis Scale for cervical dystonia. Motor assessment is completed by quality of life and functional scales, such as the Short-Form Health Survey (SF-36) or the Parkinson's Disease Questionnaire 39. Validated rating scales for cranial or upper limb dystonia are lacking., Discussion: In common clinical practice, these outcome measures can be administered in an open-label fashion because double blind assessment is only required for ascertaining new treatment indications or research purposes. The same measures are to be used postoperatively to revaluate outcome after DBS. Brain MRI is required to confirm diagnosis and assess structural abnormalities. Other imaging techniques, particularly functional imaging, are used for research purposes., (Copyright © 2011 Movement Disorder Society.)

Although lesional, neuroimaging, and brain stimulation studies have provided an insight into the neural mechanisms of judgement and decision-making, all these works focused on the cerebral cortex, without investigating the role of subcortical structures such as the basal ganglia. Besides being an effective therapeutic tool, deep brain stimulation (DBS) allows local field potential (LFP) recordings through the stimulation electrodes thus providing a physiological "window" on human subcortical structures. In this study we assessed whether subthalamic nucleus LFP oscillations are modulated by processing of moral conflictual, moral nonconflictual, and neutral statements. To do so, in 16 patients with Parkinson's disease (8 men) bilaterally implanted with subthalamic nucleus (STN) electrodes for DBS, we recorded STN LFPs 4 days after surgery during a moral decision task. During the task, recordings from the STN showed changes in LFP oscillations. Whereas the 14--30 Hz band (beta) changed during the movement executed to perform the task, the 5--13 Hz band (low-frequency) changed when subjects evaluated the content of statements. Low-frequency band power increased significantly more during conflictual than during nonconflictual or neutral sentences. We conclude that STN responds specifically to conflictual moral stimuli, and could be involved in conflictual decisions of all kinds, not only those for moral judgment. LFP oscillations provide novel direct evidence that the neural processing of conflictual decision-making spreads beyond the cortex to the basal ganglia and encompasses a specific subcortical conflict-dependent component.

The long-term efficacy and safety of deep brain stimulation (DBS) implant for Parkinson's disease (PD) is described in several recent papers. This procedure has been reported to permit a stable reduction of dopaminergic therapy requirements for up to 5 years, although some expectation of deterioration in non-dopaminergic signs has been recently stated. Our aim is to perform a literature-based review of papers available describing long-term post-operative follow-up after a bilateral implant for subthalamic DBS (STN-DBS). Only peer-reviewed published papers with a post-operative follow-up of at least 5 years were considered. Clinical outcome, disease progression and side effects were assessed at baseline and 2 (or 3 years) and 5 years after surgery. Seven papers were included in the review. A total of 238 patients were analyzed. STN-DBS was confirmed to be an effective treatment for selected patients with PD. In all studies, off-related motor symptoms improved dramatically, compared with pre-implant, at 2 (or 3, according to the study) years and this result persisted at 5-year evaluations. Antiparkinsonian drug reductions, improvements in motor fluctuations and dyskinesias, functional measures and the progression of underlying PD were also reported in all series. Some axial scores, in particular postural stability and speech, improved transiently. Persisting adverse effects included eyelid opening apraxia, weight gain, psychiatric disorders, depression, dysarthria, dyskinesias, and apathy. The present review of the 5-year observations confirms that STN-DBS is a powerful method in the management of PD, but its long-term effects must be thoroughly assessed.

Deep brain stimulation of the subthalamic nucleus represents the most important innovation for treatment of advanced Parkinson's disease. Prospective studies have shown that although the beneficial effects of this procedure are maintained at 5 years, axial motor features and cognitive decline may occur in the long term after the implants. In order to address some unsolved questions raised by previous studies, we evaluated a series of 20 consecutive patients who received continuous stimulation for 8 years. The overall motor improvement reported at 5 years (55.5% at Unified Parkinson's Disease Rating Scale-motor part, P < 0.001 compared with baseline) was only partly retained 3 years later (39%, P < 0.001, compared with baseline; -16.5%, P < 0.01, compared with 5 years), with differential effects on motor features: speech did not improve and postural stability worsened (P < 0.05). The preoperative levodopa equivalent daily dose was reduced by 58.2% at 5 years and by 60.3% at 8 years. In spite of subtle worsening of motor features, a dramatic impairment in functional state (-56.6% at Unified Parkinson's Disease Rating Scale-Activities of Daily Living, P < 0.01) emerged after the fifth year of stimulation. The present study did not reveal a predictive value of preoperative levodopa response, whereas few single features at baseline (such as gait and postural stability motor scores and the preoperative levodopa equivalent daily dose) could predict long-term motor outcome. A decline in verbal fluency (slightly more pronounced than after 5 years) was detected after 8 years. A significant but slight decline in tasks of abstract reasoning, episodic memory and executive function was also found. One patient had developed dementia at 5 years with further progression at 8 years. Executive dysfunction correlated significantly with postural stability, suggesting interplay between axial motor deterioration and cognition. Eight years after surgery, no significant change was observed on scales assessing depression or anxiety when compared with baseline. At 8 years, there was no significant increase of side-effects when compared with 5-year follow-up. In conclusion, deep brain stimulation of the subthalamic nucleus is a safe procedure with regard to cognitive and behavioural morbidity over long-term follow-up. However, the global benefit partly decreases later in the course of the disease, due to progression of Parkinson's disease and the appearance of medication- and stimulation-resistant symptoms.

Background and Importance: Meige syndrome (MS) is an adult-onset segmental dystonia characterized by the combination of upper and lower cranial involvement. Its treatment is challenging and the use of oral medication or of botulinum neurotoxin treatment is not decisive. Deep brain stimulation of the globus pallidus internum (GPi DBS) has been used occasionally in severe cases., Clinical Presentation: We report the long-term efficacy of low-voltage chronic bilateral GPi DBS in a patient with segmental dystonia featuring severe MS and cervical brachial involvement. The patient received a bilateral ventroposterolateral GPi implant. Postoperative 3-dimensional reconstruction allowed checking of the definitive position of the electrode and contacts within the targeted nucleus. Following implant, the patient received bilateral low-voltage stimulation, consisting in amplitude of 1.3 V with a pulse width of 90 microseconds and a frequency of 130 Hz, yielding a current of 23 microA. Clinical follow-up for 38 months showed a progressive and sustained improvement of dystonia with unchanged electrical settings throughout the observation period. The patient again undertook normal life activities., Conclusion: Bilateral low-voltage GPi stimulation allowed efficient control of MS symptoms and the associated brachial cervical dystonia.

We report the 5 to 6 year follow-up of a multicenter study of bilateral subthalamic nucleus (STN) and globus pallidus internus (GPi) deep brain stimulation (DBS) in advanced Parkinson's disease (PD) patients. Thirty-five STN patients and 16 GPi patients were assessed at 5 to 6 years after DBS surgery. Primary outcome measure was the stimulation effect on the motor Unified Parkinson's Disease Rating Scale (UPDRS) assessed with a prospective cross-over double-blind assessment without medications (stimulation was randomly switched on or off). Secondary outcomes were motor UPDRS changes with unblinded assessments in off- and on-medication states with and without stimulation, activities of daily living (ADL), anti-PD medications, and dyskinesias. In double-blind assessment, both STN and GPi DBS were significantly effective in improving the motor UPDRS scores (STN, P < 0.0001, 45.4%; GPi, P = 0.008, 20.0%) compared with off-stimulation, regardless of the sequence of stimulation. In open assessment, both STN- and GPi-DBS significantly improved the off-medication motor UPDRS when compared with before surgery (STN, P < 0.001, 50.5%; GPi, P = 0.002, 35.6%). Dyskinesias and ADL were significantly improved in both groups. Anti-PD medications were significantly reduced only in the STN group. Adverse events were more frequent in the STN group. These results confirm the long-term efficacy of STN and GPi DBS in advanced PD. Although the surgical targets were not randomized, there was a trend to a better outcome of motor signs in the STN-DBS patients and fewer adverse events in the GPi-DBS group., ((c) 2010 Movement Disorder Society.)

Little is known about the gender-related long-term efficacy and safety after subthalamic nucleus deep brain stimulation (STN DBS) implant for Parkinson's disease (PD), although some differences could be expected as recently stated in a short-term report. We assessed the possible gender-related differences in clinical outcome and disease progression along a 5-year period after STN DBS for PD. A prospective cohort of PD patients who underwent STN DBS and reached the 5-year follow-up (FU) was considered. Clinical outcome, disease progression and side effects were assessed at baseline and 1, 3, and 5 years after surgery. Eleven men and nine women were included in the study. At baseline, no inter-gender difference of age at implant, disease duration and severity or levodopa responsiveness was detected. A higher motor responsiveness in men compared to women was detected only at 1-year FU: this difference was mainly related to worse lower limb akinesia and gait score in women. The difference was not confirmed at 3 and 5 years. Antiparkinsonian drugs reduction, improvement in motor fluctuations and dyskinesias, functional measures and progression of underlying PD, were comparable in both groups. Women had persistent adverse events comparable to men. The present long-term observation confirms the occurrence of slight gender-related differences in PD patients treated with STN DBS, indicating a transient poorer outcome in women. Further observational time and a wider number of patients are needed to better analyze the dimension of long-term gender-related differences.

Stimulation of the subthalamic nucleus (STN) is an effective treatment for advanced Parkinson's disease (PD), but the medication requirements after implant are poorly known. We performed a long-term prospective evaluation of 20 patients maintained at stable dopaminergic therapy for 5 years after bilateral STN implants, who were evaluated 6 months, 1 year, 3 years, and 5 years after surgery. We measured, during the entire observation period, the effect of deep brain stimulation on motor and functional outcome measures, the levodopa equivalent daily dose and the total electrical energy delivered. At 5 years, the UPDRS motor score had improved by 54.2% and levodopa equivalent dose was reduced by 61.9%, compared with preimplant. Dopaminergic medication remained stable during the observation period, but energy was progressively increased over time. Rest tremor, rigidity, gait, lower and upper limb akinesia, and total axial score were improved in decreasing order. Postural stability and speech improved transiently, whereas on-period freezing of gait, motor fluctuations and dyskinesias recovered durably. Functional measures did not show improvement in autonomy and daily living activities after STN implant. Chronic STN stimulation allows to replace for dopaminergic medications in the long-term at the expense of an increase of the total energy delivered. This is associated with marked improvement of motor features without a matching benefit in functional measures.

Continuous high-frequency stimulation of the globus pallidum internum (GPi) is an accepted treatment for patients with primary dystonia. In a series of 18 consecutive dystonia cases that were successfully treated by bilateral GPi stimulation, 1 patient had an adverse event involving the downward migration of the electrodes. He developed remarkable behavioral complications and was found to have dislodgement of the left electrode to a position close to the left amygdala. The patient developed behavioral changes consisting of depression, psychotic symptoms, and heightened pain perception. This syndrome reverted when the left electrode was removed and a new one inserted in the correct position. We describe in detail the clinical features associated with left amygdala dysregulation induced by high-frequency stimulation through the displaced electrode., (2007 Movement Disorder Society)

High frequency stimulation (HFS) of the subthalamic nucleus (STN) is an efficacious symptomatic treatment for Parkinson's disease. We have analysed the genetic status of a series of consecutive parkinsonian patients implanted for STN HFS and compared the outcome of five carrying mutations in the parkin gene with that of the non-parkin group. All patients obtained sustained control of PD symptoms and achieved functional improvement; in the parkin group the UPDRS motor score improved by 56.4%, the levodopa equivalent daily dosage was reduced by 75.5%. Postoperative medications were reduced more in parkin than in non-parkin patients. We confirm that the current inclusion criteria for STN HFS do not exclude patients carrying mutations in the parkin gene; their clinical outcome is comparable to that of the non-parkin group.

Keywords: dystonia, deep brain stimulation EN dystonia, deep brain stimulation 6 8 3 01/06/21 20210101 NES 210101 Dystonia syndromes have many different causes (inherited, acquired, or idiopathic) and variable phenomenology, as dystonia can be isolated, combined with another movement disorder or with additional neurological features.1 Symptomatic treatment is based on oral medications, focal injections of botulinum neurotoxins (BoNT), or deep brain stimulation (DBS).2 In this issue of I Movement Disorders Clinical Practice i , 2 patients with inherited combined syndromes are independently described to benefit from DBS targeted to the globus pallidus internus (GPi). The possibility of using GPi DBS was first shown in patients with early-onset generalized inherited dystonia, specifically I TOR1A i (DYT1) gene mutation carriers,5 who are now known to have long-lasting benefit.6 GPi DBS is currently accepted as a first-line symptomatic indication for DYT1 dystonia. In these cases, assessment of outcome is not based on dystonia rating scales but, rather, on the number and duration of dyskinetic spells at baseline and after implant.4 These data are therefore difficult to compare with those collected in patients with other dystonia syndromes. [Extracted from the article]

ABSTRACT Background Multiplications of the SNCA gene that encodes alpha-synuclein are a rare cause of autosomal dominant Parkinson's disease (PD). Methods Here, we describe 2 novel families in which there is autosomal dominant PD associated with SNCA duplication, and we compare the clinical features of all known patients carrying 3 or 4 SNCA copies. Results Affected members in family A presented with early onset PD that was variably associated with nonmotor features, such as dysautonomia, cognitive deficits, and psychiatric disturbances. In family B, the clinical presentation ranged from early onset PD-dementia with psychiatric disturbances to late onset PD with mild cognitive impairment. Conclusions The presence of 4 SNCA copies is associated with a rich phenotype, characterized by earlier onset of motor and nonmotor features compared with patients who bear 3 SNCA copies. The clinical spectrum associated with SNCA duplications is wide, even within a single family, suggesting a role for as yet unidentified genetic or environmental modifiers. © 2013 Movement Disorder Society [ABSTRACT FROM AUTHOR]