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E Broussolle

Publications and source records attributed to E Broussolle.

At least 19 recordsLinked to original sources
PubMed2006

Subthalamic nucleus stimulation in Parkinson's disease : anatomical and electrophysiological localization of active contacts.

OBJECTIVES: 1 - To assess the anatomical localization of the active contacts of deep brain stimulation targeted to the subthalamic nucleus (STN) in Parkinson's disease patients. 2 - To analyze the stereotactic spatial distribution of the active contacts in relation to the dorsal and the ventral electrophysiologically-defined borders of the STN and the stereotactic theoretical target. METHODS: Twenty-eight patients underwent bilateral high-frequency stimulation of the STN (HFS-STN). An indirect anatomical method based on ventriculography coupled to electrophysiological techniques were used to localize the STN. Clinical improvement was evaluated by Unified Parkinson's Disease Rating Scale motor score (UPDRS III). The normalized stereotactic coordinates of the active contact centres, dorsal and ventral electrophysiologically-defined borders of the STN were obtained from intraoperative X-rays images. These coordinates were represented in a three-dimensional stereotactic space and in the digitalized atlas of the human basal ganglia. RESULTS: HFS-STN resulted in significant improvement of motor function (62.8%) in off-medication state and levodopa-equivalent dose reduction of 68.7% (p < 0.05). Most of the active contacts (78.6%) were situated close to (+/- 1.6 mm) the dorsal border of the STN (STN-DB), while 16% were dorsal and 5.4% were ventral to it. Similar distribution was observed in the atlas. The euclidean distance between the STN-DB distribution center and the active contacts distribution center was 0.31 mm, while the distance between the active contacts distribution center and the stereotactic theoretical target was 2.15 mm. Most of the space defined by the active contacts distribution (53%) was inside that defined by the STN-DB distribution. CONCLUSION: In our series, most of the active electrodes were situated near the STN-DB. This suggests that HFS-STN could influence not only STN but also the dorsal adjacent structures (zona incerta and/or Fields of Forel).

Action Potentials↗
PubMed2006

Manic behaviour induced by deep-brain stimulation in Parkinson's disease: evidence of substantia nigra implication?

We report the case of a patient who had benefited from bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease and who presented acute and reproducible manic behaviour when stimulated mainly in the substantia nigra. A positron emission tomography scan showed an activation of the right dorsolateral prefrontal and inferior temporal cortex, the left anterior cingulate cortex and a deactivation of the left insula. This suggests that changes in cortical activation related to mania are subcortically driven, involving notably the substantia nigra.

Bipolar Disorder↗
PubMed2005

[Advantages and limitations in the assessment of neuroprotective treatment of Parkinson's disease by functional imaging].

INTRODUCTION: The development of neuroprotective strategies is a crucial issue for Parkinson's disease, since up to now only symptomatic therapies are available. The clinical evaluation of neuroprotective drugs is difficult considering the long-term effect of anti-Parkinsonian medication that nearly make impossible accurate measurement of the "true" clinical stage of the disease in the early years of progression. BACKGROUND: Two recent functional imaging studies (CALM-PD and REAL-PET) using positron emission tomography (PET) or single photon emission computed tomography (SPECT), suggest that dopamine agonist may have a neuroprotective effect compared to L-Dopa. CONCLUSION: These results are still controversial, notably because of the lack of clinical-imaging correlations, the absence of a placebo group and some important methodological considerations. Nevertheless, these studies are encouraging and give some arguments for the potential neuroprotective role of dopamine agonists. The aim of this work is first to present the pros and cons of these studies and second to propose guidelines in order to improve the design and methodology for future studies designed to assess the neuroprotective properties of new drugs in Parkinson's disease.

Antiparkinson Agents↗
PubMed2004

On-line motor control in patients with Parkinson's disease.

Recent models based, in part on a study of Huntington's disease, suggest that the basal ganglia are involved in on-line movement guidance. Two experiments were conducted to investigate this idea. First, we studied advanced Parkinson's disease patients performing a reaching task known to depend on on-line guidance. The task was to 'look and point' in the dark at visual targets displayed in the peripheral visual field. In some trials, the target location was slightly modified during saccadic gaze displacement (when vision is suppressed). In both patient and control groups, the target jump induced a gradual modification of the movement which diverged smoothly from its original path to reach the new target location. No deficit was found in the patients, except for an increased latency to respond to the target jump (Parkinson's disease: 243 ms; controls: 166 ms). A computational simulation indicated that this response slowing was likely to be a by-product of bradykinesia. The unexpected inconsistency between this result and previous reports was investigated in a second experiment. We hypothesized that the relevant factor was the characteristics of the corrections to be performed. To test this prediction, we investigated a task requiring corrections of the same type as investigated in Huntington's disease, namely large, consciously detected errors induced by large target jumps at hand movement onset. In contrast with the smooth adjustments observed in the first experiment, the subjects responded to the target jump by generating a discrete corrective sub-movement. While this iterative response was relatively rapid in the control subjects (220 ms), Parkinson's disease patients exhibited either dramatically late (>730 ms) or totally absent on-line corrections. When on-line corrections were absent, the initial motor response was completed before a second corrective response was initiated (the latency of the corrective response was the same as the latency of the initial response). Considered together, these results suggest that basal ganglia dependent circuits are not critical for feedback loops involving a smooth modulation of the ongoing command. These circuits may rather contribute to the generation of discrete corrective sub-movements. This deficit is in line with the general impairment of sequential and simultaneous actions in patients with basal ganglia disorders.

Adult↗
PubMed2004

Clozapine improves dyskinesias in Parkinson disease: a double-blind, placebo-controlled study.

OBJECTIVE: To investigate the efficacy and safety of clozapine in the treatment of levodopa-induced dyskinesias (LID) in patients with severe Parkinson disease (PD). METHODS: Fifty patients were randomized to treatment in this 10-week, double-blind, parallel-group, placebo-controlled, multicenter trial. The principal measure of outcome was the diurnal change in the "on" time with LID assessed using a self-evaluation of the motor performance fluctuations performed every 2 weeks. An acute levodopa challenge was also performed at the beginning and end of the study. RESULTS: A reduction in the duration of "on" periods with LID was noted in favor of the clozapine group at the end of the study (placebo group day 0: 4.54 +/- 0.53 hours, end: 5.28 +/- 0.70 hours; clozapine group day 0: 5.68 +/- 0.66 hours, end: 3.98 +/- 0.57 hours; p = 0.003). The mean clozapine dosage was 39.4 +/- 4.5 (SEM) mg/day. The maximal LID score at rest during the levodopa challenge was significantly decreased under clozapine treatment, with a variation from day 0 to day 70 in the placebo group of +0.15 +/- 1.01 and in the clozapine group of -2.22 +/- 0.52 (p < 0.05). Five patients receiving clozapine and seven receiving placebo discontinued on account of adverse events. Among them, three patients in the clozapine group developed eosinophilia, which rapidly resolved after withdrawal of the drug. CONCLUSION: Clozapine is effective in the treatment of levodopa-induced dyskinesias in severe PD.

Aged↗
PubMed2004

[Intra-cavernous aneurysm of the internal carotid artery complicating sphenoid sinusitis].

INTRODUCTION: Mycotic or post-infectious aneurysm of the intra-cavernous portion of the internal carotid artery is uncommon. CASE REPORT: We report here the case of a patient who developed progressive left ophthalmoplegia, with left hemi-crania three weeks after a tooth extraction. The patient was febrile. Neuroradiological and microbiological analysis led to the diagnosis of sphenoidal and ethmoidal sinus infection with extension to the left cavernous sinus. An aneurysm of the intra-cavernous portion of the left internal carotid artery was also found. CONCLUSIONS: The risk of rupture for this kind of aneurysm is difficult to assess. Treatment always consists in prolonged and adapted antibiotic therapy. For certain patients neurosurgical or endovascular repair is necessary. We followed our patient for four Years without surgical intervention. The diameter of the aneurysm has remained stable.

Anti-Bacterial Agents↗
PubMed2003

Chronic subthalamic nucleus stimulation and striatal D2 dopamine receptors in Parkinson's disease--A [(11)C]-raclopride PET study.

CONTEXT: Subthalamic nucleus (STN) stimulation mechanism of action remains a matter for debate. In animals, an increased striatal dopamine (DA) release due to STN stimulation has been reported. OBJECTIVE: To determine in Parkinson's disease (PD) patients using positron emission tomography (PET) and [11C]-Raclopride, whether STN stimulation induces a striatal DA release. METHODS: Nine PD patients with bilateral STN stimulation were enrolled and underwent two [11C]-Raclopride PET scans. The scans were randomly performed in off and on stimulation conditions. Striatal [11C]-Raclopride binding potential (BP) was calculated using regions of interest and statistical parametric mapping. RESULTS: For PD patients, the mean [(11C]-Raclopride BP (+/- SD) were, in Off stimulation condition: 1.7 +/- 0.3 for the right caudate nucleus, 1.8 +/- 0.4 for the left caudate nucleus, 2.6 +/- 0.5 for the right putamenand 2.6 +/- 0.5 for the left putamen. In On stimulation condition: 1.7 +/- 0.4 for the right caudate nucleus, 1.9 +/- 0.5 for the left caudate nucleus, 2.8 +/- 0.7 for the right putamen and 2.7 +/- 0.8 for the left putamen. No significant difference of BP related to the stimulation was noted. CONCLUSION: STN stimulation does not produce significant variations of striatal DA release as assessed by PET and [11C]-Raclopride.

Adult↗
PubMed2003

Dissociable effects of dopaminergic therapy on spatial versus non-spatial working memory in Parkinson's disease.

There is now evidence for definite and early cognitive deficits in Parkinson's disease (PD), involving, in particular, executive functions and working memory. However, the distinction between visuo-spatial and non-spatial working memory deficits and the impact of dopamine on these deficits are still open to debate. The aim of this study was therefore to investigate cognitive and motor performance in PD patients in two conditional associative learning tasks requiring either spatial or non-spatial visual working memory. The subject had to point to visual targets according to the visual characteristics of memorised visual cues (colour, position and form). To assess the effect of L-dopa therapy, PD patients were studied over two consecutive days: one ON/OFF group of nine PD patients with treatment (ON condition) on the first day and without treatment (OFF condition) on the second day; and another OFF/ON group of nine PD patients tested on reverse. The PD groups were compared to a control group of nine age-matched healthy subjects. Our main data demonstrate that: (1) in PD patients with OFF treatment, the response time of manual pointing is increased mainly in the non-spatial working memory task; and (2) in PD patients with ON treatment, either the response time is normal (on the first day) or is increased in both visuo-spatial and non-spatial tasks. We suggest that this dissociation between spatial versus non-spatial working memory deficits in non-medicated PD might be related to compensatory mechanisms that occur following fronto-striatal dysfunction.

Adult↗
PubMed2003

The timing of antiparkinsonian treatment reduction after subthalamic nucleus stimulation.

The objective of this work was to precisely analyse the reduction of the antiparkinsonian treatment in 18 consecutive patients with Parkinson's disease (PD) operated on for bilateral subthalamic nucleus (STN) stimulation, first after 1 month of follow-up, then at 1 year postoperatively. Trihexyphenidyle, selegiline, entacapone, apomorphine and lisuride could be withdrawn shortly after starting STN electrical stimulation. The levodopa mean daily dose was reduced by 57% at 1 month after surgery and remained stable at 1 year. The mean ropinirole and bromocriptine daily dose decrements after surgery corresponded to 54 and 63%, respectively, at 1 month and to 77 and 40% at 1 year. At 12 months postoperatively, one third of the patients no longer received any antiparkinsonian drugs and the others were on monotherapy of either levodopa or dopamine agonists or received a combined treatment of a dopaminergic agonist and levodopa. In conclusion, STN stimulation allows a major reduction and simplification of antiparkinsonian treatment which can usually be achieved during the early postoperative period.

Aged↗
PubMed2002

Subthalamic nucleus stimulation in Parkinson's disease: clinical evaluation of 18 patients.

The aim of the present study was to assess the efficacy and safety of chronic subthalamic nucleus deep-brain stimulation (STN-DBS) in patients with Parkinson's disease (PD). 18 consecutive severely affected PD patients were included (mean age, SD: 56.9+/-6 years; mean disease duration: 13.5+/-4.4 years). All the patients were evaluated clinically before and 6 months after the surgical procedure using the Unified Parkinson's Disease Rating Scale (UPDRS). Additionally, a 12 months follow-up was available in 14 patients. The target coordinates were determined by ventriculography under stereotactic conditions, followed by electrophysiology and intraoperative stimulation. After surgery, continuous monopolar stimulation was applied bilaterally in 17 patients at 2.9+/-0.4 V through 1 (n = 31) or 2 contacts (n = 3). One patient had bilateral bipolar stimulation. The mean frequency of stimulation was 140+/-16 Hz and pulse width 68+/-13 micros. Off medication, the UPDRS part III score (max = 108) was reduced by 55 % during on stimulation (score before surgery: 44.9+/-13.4 vs at 6 months: 20.2+/-10; p < 0.001). In the on medication state, no difference was noted between the preoperative and the postoperative off stimulation conditions (scores were respectively: 17.9+/-9.2 and 23+/-12.6). The severity of motor fluctuations and dyskinesias assessed by UPDRS IV was reduced by 76 % at 6 months (scores were respectively: 10.3+/-3 and 2.5+/-3; p < 0.001). Off medication, the UPDRS II or ADL score was reduced by 52.8 % during on stimulation (26.9+/-6.5 preop versus 12.7+/-7 at 6 months). The daily dose of antiparkinsonian treatment was diminished by 65.5 % (levodopa equivalent dose -- mg/D -- was 1045 +/- 435 before surgery and 360 +/- 377 at 6 months; p < 0.01). These results remained stable at 12 months for the 14 patients studied. Side effects comprised lower limb phlebitis (n = 2), pulmonary embolism (n = 1), depression (n = 6), dysarthria and freezing (n = 1), sialorrhea and drooling (n = 1), postural imbalance (n = 1), transient paresthesias and dyskinesias. This study confirms the great value of subthalamic nucleus stimulation in the treatment of intractable PD. Some adverse events such as depression may be taken into account in the inclusion criteria and also in the post-operative outcome.

Adult↗
PubMed2002

[Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (Melas) associated with a Fahr disease and cerebellar calcifications].

INTRODUCTION: Melas syndrome is a mitochondrial disease which corresponds to the association of mitochondrial encephalopathy, lactic acidosis and stroke-like espisodes. CASE REPORT: The authors report the case of a 39 year-old woman presenting with hearing loss, seizures, visual field deficit, three stroke-like episodes and calcifications of the basal ganglia and cerebellar dentate nuclei. Melas syndrome was suspected and confirmed by muscle biopsy, showing ragged red fibers and the presence of an A3243G mutation of mitochondrial DNA. CONCLUSION: This clinical, pathological and radiological observation shows that intracerebral calcifications may involve the dentate nuclei of the cerebellum in the Melas syndrome.

Adult↗
PubMed2002

[Genetics and environmental factors of Parkinson disease].

We present a review on the genetic and environmental factors implicated in the aetiology of Parkinson's disease. The environmental hypothesis was strongly suggested about 20 years ago after the report of a parkinsonian syndrome in young adults that were intoxicated by a neurotoxin called MPTP which selectively destroys nigrostriatal dopaminergic neurons. Several chemical products used in herbicides and pesticides are similar structurally to MPTP, including paraquat, diquat and rotenone. Epidemiological studies have revealed an increased risk for Parkinson's disease with the use of pesticides and herbicides or the consumption of well water in rural areas of industrialised countries. However, it has not been possible to identify any causative environmental chemical agent in the aetiology of Parkinson's disease despite intensive research. Comparatively, the genetic hypothesis of Parkinson's disease has gained considerable interest during the last decade. Epidemiological studies reveal a family history in 10-25 p. 100 Parkinson's disease patients. Several large kindreds with autosomal dominant Parkinson's disease associated with mutations of alpha-synuclein gene (PARK 1) were recently described. alpha-synuclein is a constituant of Lewy bodies, the hallmark of idiopathic Parkinson's disease. However, alpha-synuclein gene mutations are rare as opposed to parkin gene mutations (PARK 2), which are frequently found in autosomal recessive and sporadic young onset Parkinson's disease patients. Other genes or locus are implicated in autosomal dominant familial cases (PARK 3, 4 and 5). Nevertheless, a pure genetic origin can be demonstrated only in a minority of Parkinson's disease patients. Investigation of the possible interaction between genes and environment and of several candidate genes gave contradictory results, notably concerning the association between allelic variants of CYP2D6 gene and the occurrence of Parkinson's disease. In conclusion, the aetiology of Parkinson's disease remains unknown. There are probably several types or causes of Parkinson's disease. In most cases, this heterogeneity could be attributed both to genetic and environmental factors.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2001

Asymmetric influences of pointing on saccade latency in hemi-Parkinson's disease.

The objective of this study was to investigate whether eye-hand coupling was preserved or not in PD. We studied predictive saccade performance during hand pointing in six Parkinson's disease (PD) patients with asymmetrical motor signs compared to nine age-matched healthy subjects. The motor responses (saccades and hand pointing) were elicited under open loop conditions (without vision of the hand), by a visual target stepping at a predictable location (10 degrees right and left from the centre) and time. The subjects had to simultaneously move the eyes and point with the finger to the visual target alternating at one of three fixed frequencies (0.25, 0.5 and 1 Hz), for 30 cycles. This task was performed in two sessions balanced over the subjects: one session of ocular saccades only and another session of combined ocular saccades and manual pointing. In the PD group, motor performance was perturbed particularly in terms of increased latencies of hand movements. Interestingly, during pointing, associated predictive saccade disorders were tightly related to the defects of the pointing hand. Indeed, with respect to the latency of predictive saccades alone, the predictive saccade latency during hand pointing significantly decreased in the control group and in the PD group when using the non-affected hand. In contrast, for the PD group when using the affected hand, the saccade latency was increased from the latency values of predictive saccades induced without pointing. Moreover, in the control and in the PD groups, the correlation between eye and hand latencies was highly significant, suggesting an intact eye-hand coupling. No saccadic amplitude disorders were found in either condition. These results demonstrate that eye-hand coupling is preserved in PD, as revealed by the possible beneficial or adverse effects on the ocular saccades, respectively, of the less- or more-affected hand motor responses. This eye-hand coupling mechanism likely involves regions other than the nigro-striatal pathways affected in PD.

Aged↗