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1.
Radiología (Madr., Ed. impr.) ; 66(1): 57-69, Ene-Feb, 2024. ilus, tab
Article in Spanish | IBECS | ID: ibc-229646

ABSTRACT

Los tumores cartilaginosos son un grupo amplio y heterogéneo de neoplasias caracterizadas por la presencia de una matriz condroide que presenta crecimiento lobular y patrones de calcificación en arcos y anillos o en palomitas de maíz. En RM destaca su hiperintensidad en las secuencias potenciadas en T2, y en las imágenes poscontraste, un relace lobulado o septal. En la clasificación de 2020 de la OMS, los tumores de estirpe condral se clasifican en benignos, intermedios o malignos. A pesar de los avances tecnológicos, siguen suponiendo un reto tanto para el radiólogo como para el patólogo, siendo la principal dificultad la diferenciación entre los tumores benignos y malignos, razón por la que requieren un abordaje multidisciplinar. Este trabajo recoge los principales cambios introducidos en la actualización de 2020, describe las características de imagen de los principales tumores cartilaginosos y proporciona las claves radiológicas para diferenciar entre tumores benignos y malignos.(AU)


Cartilaginous tumours are a large and heterogeneous group of neoplasms characterised by the presence of a chondroid matrix, with lobular growth and arcuate, ring-like or popcorn-like calcification patterns. MRI shows hyperintensity in T2-weighted sequences and a lobulated or septal relief in postcontrast images. In the WHO 2020 classification, chondral tumours are classified as benign, intermediate or malignant. Despite technological advances, they continue to pose a challenge for both the radiologist and the pathologist, being the main difficulty the differentiation between benign and malignant tumours, which is why they require a multidisciplinary approach. This paper describes the main changes introduced in the 2020 update, describes the imaging characteristics of the main cartilaginous tumours and provides the radiological keys to differentiate between benign and malignant tumours.(AU)


Subject(s)
Humans , Male , Female , Neoplasms/classification , World Health Organization , Osteochondroma/diagnostic imaging , Chondroma/diagnostic imaging , Chondrosarcoma/diagnostic imaging , Cartilage
2.
Radiologia (Engl Ed) ; 66(1): 57-69, 2024.
Article in English | MEDLINE | ID: mdl-38365355

ABSTRACT

Cartilaginous tumours are a large and heterogeneous group of neoplasms characterised by the presence of a chondroid matrix, with lobular growth and arcuate, ring-like or popcorn-like calcification patterns. MRI shows hyperintensity in T2-weighted sequences and a lobulated or septal relief in postcontrast images. In the WHO 2020 classification, chondral tumours are classified as benign, intermediate or malignant. Despite technological advances, they continue to pose a challenge for both the radiologist and the pathologist, being the main difficulty the differentiation between benign and malignant tumours, which is why they require a multidisciplinary approach. This paper describes the main changes introduced in the 2020 update, describes the imaging characteristics of the main cartilaginous tumours and provides the radiological keys to differentiate between benign and malignant tumours.


Subject(s)
Bone Neoplasms , Chondrosarcoma , Humans , Chondrosarcoma/diagnostic imaging , Chondrosarcoma/pathology , Bone Neoplasms/diagnostic imaging , Radiography , Magnetic Resonance Imaging/methods , World Health Organization
3.
Rev Neurol (Paris) ; 178(4): 347-354, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34565624

ABSTRACT

INTRODUCTION: Non-motor fluctuations (NMF) in Parkinson's disease (PD) remain poorly recognized but have a high impact on patients' quality of life. The lack of assessment tools limits our understanding of NMF, compromising appropriate management. Our objective was to validate a hetero-questionnaire for NMF in PD patients at different stages of the disease: without treatment, without motor fluctuations, with motor fluctuations. METHODS: We included patients in 15 centers in France. Our questionnaire, NMF-Park, resulted from previous studies, allowing us to identify the more pertinent NMF for evaluation. Patients reported the presence (yes or no) of 22 selected NMF, and their link with dopaminergic medications. The assessment was repeated at one and two years to study the progression of NMF. We performed a metrological validation of our questionnaire. RESULTS: We included 255 patients (42 without treatment, 88 without motor fluctuations and 125 with motor fluctuations). After metrological validation, three dimensions of NMF were found: dysautonomic; cognitive; psychiatric. The sensory/pain dimension described in the literature was not statistically confirmed by our study. DISCUSSION: Our questionnaire was validated according to clinimetric standards, for different stages of PD. It was clinically coherent with three homogeneous dimensions. It highlighted a link between fatigue, visual accommodation disorder, and cognitive fluctuations; and the integration of sensory/pain fluctuations as part of dysautonomic fluctuations. It focused exclusively on NMF, which is interesting considering the described differences between non-motor and motor fluctuations. CONCLUSION: Our study validated a hetero-questionnaire of diagnosis for NMF for different stages of PD.


Subject(s)
Parkinson Disease , Primary Dysautonomias , Humans , Pain , Parkinson Disease/therapy , Quality of Life , Surveys and Questionnaires
4.
Neuroscience ; 437: 207-214, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32339627

ABSTRACT

Defective proprioceptive integration may play a role in the pathophysiology of motor symptoms in Parkinson's disease (PD). Dysfunction related to proprioceptively-evoked postural reactions in PD patients is still a controversial issue, with only a limited number of studies to date and mostly discordant results. The aims of the present study were (1) to determine whether or not the proprioceptive defect in PD underlies postural impairment and (2) whether or not deep brain stimulation of the subthalamic nucleus (STN-DBS) affects proprioceptive integration. We examined proprioceptive integration during a postural task in 13 PD patients and 12 age-matched control subjects, using a muscle-tendon vibration paradigm. Analysis of the center of pressure displacement and kinematic data indicates a greater degree of postural destabilization and a reduced ability to maintain a vertical orientation in PD. We found a significant positive effect of STN-DBS on these postural features. Our findings indicate that Parkinson patients, even in the absence of any clinical evidence of instability, falls, or freezing, use proprioceptive information for postural control less efficiently than healthy subjects. Furthermore, STN-DBS was found to improve proprioceptive integration, with positive impacts on postural orientation and balance.


Subject(s)
Deep Brain Stimulation , Parkinson Disease , Subthalamic Nucleus , Humans , Parkinson Disease/therapy , Postural Balance , Proprioception
5.
Rev Neurol (Paris) ; 176(7-8): 608-613, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32164972

ABSTRACT

INTRODUCTION: Multiple system atrophy (MSA) is a neurodegenerative disorder in which vocal fold mobility can be affected, sometimes leading to life-threatening situations. Our aim was to know if laryngeal examination could help differentiate MSA from Parkinson's disease (PD). MATERIALS AND METHODS: Between 2004 to 2014, all consecutive patients diagnosed with probable MSA were included in this retrospective, monocentric study. Flexible laryngoscopy was obtained in 51 MSA patients and compared with 27 patients with Parkinson's disease (PD). Laryngeal muscles EMG was available in 6 MSA patients. RESULTS: Vocal fold motion impairments (VFMI) was found in 35 (68.6%) MSA patients: 15 (29.4%) had uni- or bilateral vocal fold abnormal movement (VFAM), 13 (25.5%) had uni- or bilateral vocal fold abductor paresis (VFABP), 4 (7.8%) had uni- or bilateral vocal fold adductor paresis (VFADP), 10 (19.6%) had bilateral vocal fold paralysis (BVFP). VFMI was found in 13 PD patients (48.1%) all of whom had VFADP. Presence of BVFP was found associated with stridor (P<0.001) and dysphagia (P=0.002). In all muscles examined in 6 MSA patients, the EMG showed neuropathic patterns. CONCLUSIONS: Our data support that VFMI may be encountered in two-thirds of MSA with a variable degree of gravity. Laryngological examination should be considered as a supplementary tool for the diagnosis and prognosis of MSA. VFMI in particular VFAM, VFABD and BVFP should be discussed as an additional possible red flag even at an early stage of MSA and could help discriminate MSA from PD.


Subject(s)
Multiple System Atrophy , Parkinson Disease , Humans , Prevalence , Retrospective Studies , Vocal Cords
6.
Rev Neurol (Paris) ; 173(6): 406-410, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28461026

ABSTRACT

BACKGROUND: While it is known that 22q11.2 microdeletions (22q11.2-del) increase the risk of Parkinson's disease (PD), the characteristics of PD associated with 22q11.2-del have not been specifically explored. OBJECTIVE: This report aimed to assess the clinical characteristics and treatment responses of PD patients with 22q11.2-del, and to describe any features that might lead neurologists to investigate the comorbidity. METHODS: Nine PD patients (eight men, one woman) with 22q11.2-del were followed at seven centers of the French PD Expert Network (Ns-Park). RESULTS: PD diagnosis was made before 22q11.2-del diagnosis in seven cases; their main characteristics were early onset (32-48 years) and good initial levodopa sensitivity, but with a course characterized by severe and early-onset levodopa-induced motor complications and psychiatric manifestations. Three patients received deep brain stimulation (DBS) that was effective. CONCLUSION: Searching for 22q11.2-del in PD patients presenting with suggestive features is relevant as the clinical presentation is similar to idiopathic PD, but with other associated characteristics, including a severe evolution. Results with DBS are similar to those reported for idiopathic PD.


Subject(s)
22q11 Deletion Syndrome/complications , Parkinson Disease/complications , 22q11 Deletion Syndrome/diagnosis , 22q11 Deletion Syndrome/therapy , Adult , Cohort Studies , Deep Brain Stimulation , Female , France , Humans , Levodopa/therapeutic use , Male , Middle Aged , Parkinson Disease/diagnosis , Parkinson Disease/genetics , Parkinson Disease/therapy , Phenotype , Treatment Outcome
7.
Water Res ; 114: 1-13, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28214720

ABSTRACT

Olive mill wastewater (OMW) is a major waste stream resulting from numerous operations that occur during the production stages of olive oil. The resulting effluent contains various organic and inorganic contaminants and its environmental impact can be notable. The present work aims at investigating the efficiency of (i) jet-loop reactor with ultrafiltration (UF) membrane system (Jacto.MBR), (ii) solar photo-Fenton oxidation after coagulation/flocculation pre-treatment and (iii) integrated membrane filtration processes (i.e. UF/nanofiltration (NF)) used for the treatment of OMW. According to the results, the efficiency of the biological treatment was high, equal to 90% COD and 80% total phenolic compounds (TPh) removal. A COD removal higher than 94% was achieved by applying the solar photo-Fenton oxidation process as post-treatment of coagulation/flocculation of OMW, while the phenolic fraction was completely eliminated. The combined UF/NF process resulted in very high conductivity and COD removal, up to 90% and 95%, respectively, while TPh were concentrated in the NF concentrate stream (i.e. 93% concentration). Quite important is the fact that the NF concentrate, a valuable and polyphenol rich stream, can be further valorized in various industries (e.g. food, pharmaceutical, etc.). The above treatment processes were found also to be able to reduce the initial OMW phytotoxicity at greenhouse experiments; with the effluent stream of solar photo-Fenton process to be the least phytotoxic compared to the other treated effluents. A SWOT (Strength, Weakness, Opportunities, Threats) analysis was performed, in order to determine both the strengths of each technology, as well as the possible obstacles that need to overcome for achieving the desired levels of treatment. Finally, an economic evaluation of the tested technologies was performed in an effort to measure the applicability and viability of these systems at real scale; highlighting that the cost cannot be regarded as a 'cut off criterion', since the most cost-effective option in not always the optimum one.


Subject(s)
Olea/chemistry , Wastewater/chemistry , Filtration , Industrial Waste , Oxidation-Reduction , Waste Disposal, Fluid
8.
Rev Neurol (Paris) ; 172(8-9): 488-502, 2016.
Article in English | MEDLINE | ID: mdl-27561438

ABSTRACT

Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are two atypical parkinsonian syndromes first described half a century ago. The spectrum of these conditions as well as, more generally, the concept of tauopathy have dramatically changed over the past decade and especially in recent years. In particular, clinicopathological correlations have led to the description of several subtypes of these diseases and the features they share with other neurodegenerative diseases. The present paper is a review of how the concepts of PSP and CBD have evolved over time. In particular, it focuses on the different presentations of the disease and the overlapping syndromes that can complicate the differential diagnoses. Also discussed are some of the tools that may prove useful in making a diagnosis. Indeed, differential diagnosis issues are of particular importance in light of the likely emergence of pathology-specific disease-modifying therapies in the near future.


Subject(s)
Neurodegenerative Diseases , Supranuclear Palsy, Progressive , Basal Ganglia/pathology , Basal Ganglia Diseases/diagnosis , Basal Ganglia Diseases/etiology , Basal Ganglia Diseases/therapy , Diagnosis, Differential , Humans , Neurodegenerative Diseases/diagnosis , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/therapy , Parkinsonian Disorders/complications , Parkinsonian Disorders/diagnosis , Parkinsonian Disorders/therapy , Supranuclear Palsy, Progressive/diagnosis , Supranuclear Palsy, Progressive/etiology , Supranuclear Palsy, Progressive/therapy , Tauopathies/complications , Tauopathies/diagnosis , Tauopathies/therapy
9.
Rev Neurol (Paris) ; 172(8-9): 408-415, 2016.
Article in English | MEDLINE | ID: mdl-27561439

ABSTRACT

Tremor is a highly prevalent movement disorder that markedly reduces quality of life. The management of severe tremor is particularly challenging. Pharmacological treatment is available, but no real breakthrough has emerged recently. Propranolol and primidone are still the two most recommended agents, followed by topiramate. However, surgical treatments for medically refractory tremors are expanding. Gamma knife (GK) thalamotomy is an option particularly suitable for patients who are not candidates for deep brain stimulation. Owing to the fact that it is a non-invasive procedure without craniotomy, GK radiosurgery has almost no contraindications. Since the late 1990s, more than 250 case reports and patient series have been published. Most of these studies show that unilateral GK thalamotomy is well tolerated and reduces tremor disability. A recent study with prospective blinded assessment has confirmed its safety, together with significant improvements in tremor scores and activities of daily living.


Subject(s)
Anticonvulsants/therapeutic use , Essential Tremor/therapy , Botulinum Toxins, Type A/therapeutic use , Essential Tremor/diagnostic imaging , Essential Tremor/drug therapy , Essential Tremor/radiotherapy , Humans , Radiosurgery , Thalamus/radiation effects , Thalamus/surgery
10.
Eur J Clin Pharmacol ; 72(4): 423-30, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26936272

ABSTRACT

PURPOSE: Levodopa is the reference treatment for Parkinson's disease. However, after several years of treatment, dyskinesia may occur and strategies to overcome this side effect still need to be explored. We identified a unique population pharmacokinetic/pharmacodynamic model in Parkinson's disease to investigate the relationship and dissociability of motor response and dyskinesia. METHODS: Thirty parkinsonian patients (Hoehn and Yahr stages 3-4), treated with levodopa and suffering from peak-dose dyskinesia, were included in a prospective open-label study. They received a single dose of levodopa equal to 150 % of their usual daily dose. Blood samples, motor evaluations (UPDRS III scale) and peak-dose dyskinesia (Goetz scale) were examined after administration. A population pharmacokinetic/pharmacodynamic (PK/PD) model was developed using NONMEM software. RESULTS: Pharmacokinetic analysis identified a one-compartment model with the following parameter values [bootstrap 95 % CI]: absorption rate constant (KA) 1.86 1/h [1.08-3.25], clearance 36.6 L/h [31.3-42.8], and volume of distribution 42.9 L [34.3-52.3]. Between-subject variability was 122 % [71-183] and 38 % [26-47] for KA and clearance, respectively. Residual variability was 1120 µg/L [886-1290]. UPDRS III and dyskinesia were best described with an effect compartment and similar KE0 values of 1.37 1/h [1.01-1.77]. For UPDRS III, the E0, EC50, Emax, and Hill coefficient were 31.4 [28.4-35.3], 1410 µg/L [1200-1700], 0.72 [0.71-0.75], and 4.26 [3.20-5.58], respectively. For dyskinesia, the EC50 and Emax were 6280 µg/L [3420-37,900] and 17.9 [12.3-80.8], respectively. Residual variability was 3.15 [2.75-3.53] for UPDRS III and 2.66 [1.94-3.51] for dyskinesia. No covariates influenced the parameters. CONCLUSIONS: In patients treated with levodopa and suffering from dyskinesia, the motor response and dyskinesia have close onsets and duration effects. Maximal motor response tends to be inevitably associated with dyskinesia.


Subject(s)
Antiparkinson Agents/adverse effects , Antiparkinson Agents/therapeutic use , Dyskinesia, Drug-Induced/etiology , Levodopa/adverse effects , Levodopa/therapeutic use , Parkinson Disease/drug therapy , Aged , Female , Humans , Male , Middle Aged , Models, Biological , Prospective Studies
11.
Rev Neurol (Paris) ; 171(5): 415-25, 2015 May.
Article in English | MEDLINE | ID: mdl-25862370

ABSTRACT

Essential tremor is the most common movement disorder in adults. It is characterized by a postural and kinetic tremor affecting the arms, but it can also affect other body parts. It evolves gradually and can be responsible for a functional impairment in activities of daily living. Its pathophysiology remains poorly understood and effective therapeutic options are limited. There are significant semiological variations between patients, and the term "essential tremor" seems to encompass a wide range of heterogeneous clinical phenotypes. The diagnostic criteria presented in 1998 are now challenged. Furthermore, there is a current debate concerning the etiology of this affection, as to whether essential tremor is a complex degenerative disorder or a functional reversible disorder of neuronal oscillation. In this review, we summarize some aspects of clinical, etiologic and therapeutic news, to better address the questioning on unravelling the clinical presentation and examine the current pathophysiological controversy in this disorder.


Subject(s)
Essential Tremor/therapy , Cerebellum/physiopathology , Disease Progression , Essential Tremor/diagnosis , Essential Tremor/physiopathology , Essential Tremor/psychology , Humans
12.
Neurophysiol Clin ; 44(1): 77-86, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24502908

ABSTRACT

OBJECTIVES: Both stabilization and orientation components of postural control are affected in Parkinson's disease (PD). These deficits are partly due to proprioceptive impairments, which frequently coexist with a visual dependence. This study aimed to evaluate if a visual biofeedback - i.e. real time anteroposterior trunk and head orientations indicated with a simplified avatar and represented in a head-mounted display - could improve the postural control of PD patients in response to a postural disturbance. The influence of focusing on one specific component of the postural control (stabilization or orientation) was also examined. METHODS: Seventeen medicated PD patients performed sequences of pull-tests, either with eyes open, eyes closed or visual biofeedback, crossed with the verbal instruction to focus either on the stabilization or on the vertical body orientation. Kinematics data were collected. RESULTS: Backward trunk tilts consequent to the pulls were unchanged across the different conditions. With eyes open and eyes closed, patients did not recover their initial vertical orientation by adopting a slightly tilted backward position. This bias disappeared with the visual biofeedback. Moreover, falls consecutive to the test were significantly less frequent with the visual biofeedback than in the two other visual conditions. These different orientation and stabilization parameters were not affected by the instruction. CONCLUSION: Unlike a verbal instruction, visualizing in real time their own body's geometry improved both components of postural control of PD patients. This provides evidences in PD about links between impaired vertical orientation, deficits in balance control, and contribution of supplementary sensory cues.


Subject(s)
Biofeedback, Psychology , Feedback, Sensory , Parkinson Disease/rehabilitation , Postural Balance , Aged , Female , Humans , Male , Middle Aged , Parkinson Disease/physiopathology , Proprioception
13.
J Neurol Neurosurg Psychiatry ; 85(10): 1167-73, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24249783

ABSTRACT

OBJECTIVE: To report the short-term (1 year) and long-term (5 years) outcome of patients with Parkinson's disease (PD) with subthalamic nucleus (STN) stimulation operated upon under controlled general anaesthesia (GA). METHODS: 213 consecutive patients with PD were included between January 2000 and March 2009 and operated upon under a particular type of GA with close control of the level of sedation allowing intraoperative recordings. 188 patients were assessed 1 year postoperatively. 65 patients also completed the long-term observation period and were evaluated 5 years postoperatively. RESULTS: The Unified PD Rating Scale III score in the 'Off drug--On stim' condition was improved at 1 year and 5 years by 61% and 37%, respectively, (p<0.001). Motor complications decreased at short-term and long-term by 68% and 65%, respectively, for dyskinesia and by 52% and 48%, respectively, for fluctuations, (p<0.001). Dopaminergic treatment could also be reduced at short-term and long-term by 46% and 49%, respectively (p<0.001). There was no significant modification of mood and cognition assessments (Mattis scale and Beck depression inventory) at 1 year and 5 years. Concerning the main adverse events related to the surgery, we report four haematomas (1.9%) with two deaths (0.9%), eight cases of transient confusion (3.7%) and no epileptic seizure. CONCLUSIONS: Our results confirm that STN stimulation performed under controlled GA is efficient and has similar short-term and long-term motor effects than intervention under local anaesthesia. Furthermore, this specific procedure is not associated with more adverse events. The success of such an intervention requires strict anaesthetic monitoring and accurate STN identification.


Subject(s)
Anesthesia, General/adverse effects , Deep Brain Stimulation/methods , Deep Sedation/adverse effects , Parkinson Disease/therapy , Subthalamic Nucleus/physiology , Aged , Deep Brain Stimulation/adverse effects , Electrodes, Implanted/adverse effects , Female , Humans , Levodopa/therapeutic use , Male , Middle Aged , Parkinson Disease/drug therapy , Psychiatric Status Rating Scales , Treatment Outcome
14.
Rev Neurol (Paris) ; 168(8-9): 624-33, 2012.
Article in English | MEDLINE | ID: mdl-22921247

ABSTRACT

INTRODUCTION: In Parkinson's disease, the degeneration of the dopaminergic system and the longstanding exposure to dopamine replacement therapy (DRT) may cause, in a group of vulnerable patients, dysregulation of the brain reward system. STATE OF THE ARTS: These patients develop DRT-related compulsions, which include addiction to levodopa or dopamine dysregulation syndrome (DDS), punding, and impulse control disorders (ICDs). ICDs or behavioral addiction reported in Parkinson's disease include pathological gambling, hypersexuality, compulsive buying and binge eating. Although the underlying pathophysiology is still poorly understood, these behaviors are linked by their reward-based and repetitive nature. Such behaviors may result in devastating psychosocial impairment for the patients and are often hidden. PERSPECTIVE AND CONCLUSIONS: The recognition of these behaviors is important and allows a better clinical management. Although the limited data do not permit particular therapeutic strategies, some approaches are worth considering: DRT reduction, trials of non-dopaminergic medications and subthalamic chronic stimulation.


Subject(s)
Behavior, Addictive/chemically induced , Dopamine/adverse effects , Dopamine/therapeutic use , Parkinson Disease/drug therapy , Behavior, Addictive/epidemiology , Behavior, Addictive/therapy , Brain/drug effects , Brain/physiopathology , Compulsive Behavior/chemically induced , Compulsive Behavior/epidemiology , Compulsive Behavior/therapy , Disruptive, Impulse Control, and Conduct Disorders/chemically induced , Disruptive, Impulse Control, and Conduct Disorders/epidemiology , Disruptive, Impulse Control, and Conduct Disorders/therapy , Humans , Models, Biological , Parkinson Disease/complications , Parkinson Disease/therapy , Reward
15.
J Neurol Neurosurg Psychiatry ; 82(5): 569-73, 2011 May.
Article in English | MEDLINE | ID: mdl-20935326

ABSTRACT

BACKGROUND: Although deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a highly effective therapeutic intervention in severe Parkinson's disease, its mechanism of action remains unclear. One possibility is that DBS suppresses local pathologically synchronised oscillatory activity. METHODS: To explore this, the authors recorded from DBS electrodes implanted in the STN of 16 patients with Parkinson's disease during simultaneous stimulation (pulse width 60 µs; frequency 130 Hz) of the same target using a specially designed amplifier. The authors analysed data from 25 sides. RESULTS: The authors found that DBS progressively suppressed peaks in local field potential activity at frequencies between 11 and 30 Hz as voltage was increased beyond a stimulation threshold of 1.5 V. Median peak power had fallen to 54% of baseline values by a stimulation intensity of 3.0 V. CONCLUSION: The findings suggest that DBS can suppress pathological 11-30 Hz activity in the vicinity of stimulation in patients with Parkinson's disease. This suppression occurs at stimulation voltages that are clinically effective.


Subject(s)
Brain/physiopathology , Cortical Synchronization , Deep Brain Stimulation , Parkinson Disease/therapy , Cortical Synchronization/physiology , Deep Brain Stimulation/methods , Electroencephalography , Humans , Parkinson Disease/physiopathology
16.
Neurophysiol Clin ; 40(4): 201-8, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20674816

ABSTRACT

SUMMARY OBJECTIVE: The excitability of the lower-limb area of the motor cortex was investigated in patients with Parkinson's disease (PD) and in control subjects. Our results were compared to literature data assessing upper-limb cortical area. We analysed the effect of dopaminergic substitution therapy (DST). METHODS: Motor evoked potential (MEP) were assessed with transcranial magnetic stimulation (TMS) in 24 PD patients with (ON) and without (OFF) DST, and nine age-matched controls. RESULTS: Resting motor threshold (RMT), active motor threshold (AMT), cortical silent period (CSP), MEP amplitude and area did not differ significantly between groups and medication states. A paired-pulse TMS study revealed normal short-interval intracortical inhibition (SICI) but impaired intracortical facilitation (ICF) in PD OFF, partially normalized under DST. Post-hoc analysis uncovered two opposite effects of DST on MEP amplitude, separating the population in two groups. The paired-pulse study confirmed this division, showing that both groups exhibited distinct intracortical functioning, which was differently influenced by DST. CONCLUSIONS: The lower-limb motor cortical areas of PD patients essentially exhibited an ICF reduction whereas in upper-limb areas, literature data demonstrated impairment of both SICI and ICF. Our data revealed two groups of patients showing different excitability states and opposite responses to DST. SIGNIFICANCE: The defective ICF in lower-limb areas could play a key role in the pathophysiology of gait disorders in PD. The fact that two cortical excitability states are inversely influenced by DST may reflect different conditions of denervation and compensatory mechanisms progression.


Subject(s)
Antiparkinson Agents/therapeutic use , Dopamine Agents/therapeutic use , Levodopa/therapeutic use , Motor Cortex/physiopathology , Parkinson Disease/physiopathology , Aged , Evoked Potentials, Motor/drug effects , Evoked Potentials, Motor/physiology , Female , Humans , Male , Middle Aged , Motor Cortex/drug effects , Parkinson Disease/drug therapy , Transcranial Magnetic Stimulation
17.
Article in English | WPRIM (Western Pacific) | ID: wpr-632450

ABSTRACT

p style=text-align: justify;strongOBJECTIVE:/strong To describe a new sail shaped excision technique for alar lift surgery and present the outcome of this technique through photo documentation. br /br /strongMETHODS:/strongbr /strongDesign:/strong Surgical Innovation; Case series br /strongSetting:/strong Tertiary Government Hospital br /strongParticipants:/strong Four patients underwent alar rim lift procedure using sail excision technique performed by the senior co-author. The indication for sail excision technique was a hanging ala (type IV) based on the classification of alar-columellar discrepancies by Gunter emet al/em. The outcomes were described with comparison of pre-operative and post-operative photographs.br /br /strongRESULTS:/strong Post-operative improvement of the alar-columellar relationship and counter-rotation of the tip, the gull's wing in flight was further enhanced. There were no scar contracture or vestibular stenosis, and scars were aesthetically acceptable.br /br /strongCONCLUSION: /strongAlar lift surgery demands an accurate diagnosis and analysis of the alar-columellar discrepancies. In Southeast Asian noses, unlike Caucasian noses, the most common indication for alar surgery are wide and overhanging ala. Our proposed technique is an easy and safe method of correcting alar overhang. This procedure with its advantages represents a new, reliable and simple way of achieving predictable results in many rhinoplasty cases./p


Subject(s)
Humans , Female , Adult , General Surgery , Nose , Cosmetic Techniques , Documentation , Diagnosis , Rhinoplasty
18.
Mult Scler ; 15(3): 355-62, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19153175

ABSTRACT

The aim of the present study was to determine the sensitivity and the profile of motor evoked potentials (MEP) in patients with clinically isolated syndrome (CIS) suggestive of multiple sclerosis (MS). We measured the central motor conduction time (CMCT), amplitude ratio (AR), and surface ratio (SR) in tibialis anterior and first dorsal interosseous muscles in 22 patients with CIS. In 12 patients, the triple stimulation technique (TST) was also performed. AR was abnormal in 50% of patients, CMCT in 18% of patients, and TST in 25% of patients. AR had the highest sub-clinical sensitivity and the best positive predictive value. In the absence of clinical pyramidal signs, an early AR decrease seems to result from demyelination inducing excessive temporal dispersion of the MEP, while in territories with clinical pyramidal signs, it seems to result from conduction failure, which suggests that clinical pyramidal signs may be attributable to conduction failure. This study demonstrates that MEP, especially the AR, is sensitive to motor pathway dysfunction right from the early stages of MS.


Subject(s)
Electrodiagnosis/methods , Evoked Potentials, Motor , Motor Neurons/physiology , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Adult , Demyelinating Diseases/diagnosis , Demyelinating Diseases/physiopathology , Early Diagnosis , Female , Humans , Male , Middle Aged , Neural Conduction , Prospective Studies , Pyramidal Tracts/physiopathology , Sensitivity and Specificity , Young Adult
19.
Eur J Neurosci ; 28(8): 1686-95, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18657185

ABSTRACT

It is unclear how subthalamic nucleus activity is modulated by the cerebral cortex. Here we investigate the effect of transcranial magnetic stimulation (TMS) of the cortex on oscillatory subthalamic local field potential activity in the 8-35 Hz (alpha/beta) band, as exaggerated synchronization in this band is implicated in the pathophysiology of parkinsonism. We studied nine patients with Parkinson's disease (PD) to test whether cortical stimulation can modulate synchronized oscillations in the human subthalamic nucleus. With patients at rest, single-pulse TMS was delivered every 5 s over each primary motor area and supplementary motor area at intensities of 85-115% resting motor threshold. Subthalamic local field potentials were recorded from deep brain stimulation electrodes implanted into this nucleus for the treatment of PD. Motor cortical stimulation suppressed beta activity in the subthalamic nucleus from approximately 0.2 to 0.6 s after TMS (repeated measures anova; main effect of time, P < 0.01; main effect of side, P = 0.03), regardless of intensity. TMS over the supplementary motor area also reduced subthalamic beta activity at 95% (P = 0.05) and 115% resting motor threshold (P = 0.01). The oscillatory activity decreased to 80 +/- 26% of baseline (averaged across sites and stimulation intensities). Suppression with subthreshold stimuli confirmed that these changes were centrally driven and not due to peripheral afference. The results may have implications for mechanisms underlying the reported therapeutic benefits of cortical stimulation.


Subject(s)
Beta Rhythm , Biological Clocks/physiology , Motor Cortex/physiology , Neural Inhibition/physiology , Subthalamic Nucleus/physiology , Transcranial Magnetic Stimulation/methods , Action Potentials/physiology , Aged , Deep Brain Stimulation , Electrodes, Implanted , Evoked Potentials/physiology , Female , Humans , Male , Middle Aged , Motor Cortex/anatomy & histology , Neural Pathways/anatomy & histology , Neural Pathways/physiology , Neurons/physiology , Parkinson Disease/physiopathology , Parkinson Disease/therapy , Subthalamic Nucleus/anatomy & histology
20.
Br J Neurosurg ; 21(2): 228-30, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17453794

ABSTRACT

We report an unusual case of spinal Langerhans' cell histiocytosis of the cervicothoracic junction in a young adult man. A 17-year-old male was referred to our institution with a 3-week history of cervicothoracic pain associated to a weakness of his right upper limb. Computed tomography and magnetic resonance imaging showed a collapsed T1 vertebral body with epidural soft tissue showing mass effect on spinal cord. The patient underwent a classic anterior cervicotomy. Complete removal of the lesion could be achieved, but the soft consistency of C7 and T2 body precluded a solid anterior fixation and an extended resection of C7 and T2 body had to be performed. Then a C6 - T3 stabilisation using an anterior plate fixation and cyanomethylacrylate graft was performed. Postoperative course was uneventful. At 2 years follow-up, the patient was asymptomatic and radiological workup showed a perfect stability of anterior fixation system. Aggressive surgical management of eosinophilic granuloma should be considered in some selected cases particularly when spinal instability or neurological deficit occurs. In this young patient a modified anterior cervicotomy allowed a comfortable approach to the anterior aspect of T3 vertebra for spinal fixation.


Subject(s)
Eosinophilic Granuloma/surgery , Neck Pain/surgery , Spinal Diseases/surgery , Adolescent , Eosinophilic Granuloma/complications , Eosinophilic Granuloma/pathology , Humans , Intraoperative Care/methods , Magnetic Resonance Imaging , Male , Neck Pain/etiology , Spinal Cord Compression/etiology , Spinal Cord Compression/surgery , Spinal Diseases/diagnostic imaging , Spinal Diseases/pathology , Spinal Fusion/methods , Tomography, X-Ray Computed
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