- Email: [email protected]
P7.13 Neurophysiological assessment through visual evoked potentials and tensiomyography on multiple sclerosis patients
S92 P7.10 Cortical sources of resting state electroencephalographic rhythms in Parkinson’s disease related dementia and Alzheimer’s disease P. Buffo1 , F. Vecchio2 , M.F. De Pandis3 , C. Babiloni4 , P.M. Rossini5 Dip. Fisiologia e Farmacologia, University “Sapienza”, Rome, Italy, 2 A.Fa.R., Dip. Neurosci. Osp. FBF; Isola Tiberina, Rome, Italy, 3 Casa di Cura San Raffaele Cassino, Cassino, Italy, 4 Department of Biomedical Sciences, University of Foggia, Foggia, Italy, 5 Neurol. University “Campus Biomedico”, Rome, Italy
1
Introduction: Neurodegenerative disorders inducing cognitive impairment include Parkinson’s disease (PD) and Alzheimer’s disease (AD). Even in the early stages of PD, cognitive deficits are found in the majority of patients even if with no impact on their global abilities within the cognitive spectrum. Objective: Does cortical source mapping of resting state electroencephalographic (EEG) rhythms characterize neurodegenerative disorders inducing cognitive impairment such as Parkinson’s disease related dementia (PDD) and AD? Methods: To address this issue, eyes-closed resting state EEG rhythms were recorded in 13 PDD, 20 AD, and 20 normal elderly (Nold) subjects. Age, gender, and education were carefully matched across the three groups. Mini mental state evaluation (MMSE) score probed subjects’ global cognitive status, and was matched between the PDD and AD groups. EEG rhythms of interest were delta (2 4 Hz), theta (4 8 Hz), alpha1 (8 10.5 Hz), alpha2 (10.5 13 Hz), beta1 (13 20 Hz), and beta2 (20 30 Hz). EEG cortical sources were estimated by low resolution brain electromagnetic source tomography (LORETA). Results: With respect to the Nold and AD groups, the PPD group was characterized by peculiar abnormalities of central delta sources and posterior cortical sources of theta and beta1 rhythms. With respect to the Nold group, the PDD and AD groups mainly pointed to lower posterior cortical sources of alpha1 rhythms, which were positively correlated to MMSE score across all PDD and AD subjects as a whole (the lower the alpha sources, the lower the MMSE score). This alpha decrease was greater in the AD than PPD patients. Conclusions: The results suggest that topography and frequency of eyesclosed resting state cortical EEG rhythms distinguished PDD and AD groups, suggesting different topographic tracks of neurodegeneration and effects on the cortical neural synchronization mechanisms generating EEG rhythms in PDD and AD patients. P7.11 Corticomuscular system tunes to external perturbations during a motor task as revealed by corticomuscular coherence S.F. Campfens1 , A.C. Schouten2 , H. van der Kooij2 , M.J.A.M. van Putten1 1 Clinical Neurophysiology, MIRA institute, University of Twente, Enschede, Netherlands, 2 Laboratory of Biomechanical Engineering, MIRA Institute, University of Twente, Enschede, Netherlands Introduction: Functional coupling between cortex and muscles during a motor task can be quantified using EEG-EMG coherence. This corticomuscular coherence (CMC) is found during a static isometric task in the beta band (15 30 Hz). The CMC serves as a measure of corticomuscular integrity. Questions that remain unanswered include the causal relation between the EEG and EMG signal and the (patho-)physiological relevance of CMC in health and various neurological conditions. Objective: In this study we investigated the effect of adding small position perturbations on the CMC during a static force task. Perturbations are necessary for closed loop system identification of the corticomuscular system. Potential clinical applications of this identification include the differential diagnosis of several movement disorders. Methods: Healthy volunteers (n = 2) were instructed to exert a constant force against the handle of a wrist manipulator with their right hand. In the baseline condition, the handle of the manipulator fixed the wrist position. In the perturbation condition the handle moved following a profile consisting of a sum of sine waves, containing power at prime frequencies between 7 and 31 Hz. CMC was estimated using nonoverlapping epochs of 2 seconds. Results: During the perturbation condition significant CMC was found at the perturbation frequencies above 11 Hz; below 11 Hz not all perturbation frequencies showed CMC. Beta band CMC present in the baseline condition was preserved during the perturbation.
Poster presentations: Poster session 7. Movement disorders
2
Conclusions: This pilot shows that the corticospinal system can tune to external perturbations during a motor task. The preservation of baseline beta band CMC during the perturbation indicates that the perturbation does not influence the system at frequencies that are not excited. The different effect of perturbations below and above 11 Hz could indicate a difference in information processing in different frequency bands, further experiments are needed to clarify this. P7.12 Unilateral pedunculopontine stimulation improves electromyographic activation patterns during gait in selected patients with Parkinson’s disease P. Caliandro1,2,3 , A. Insola3,4 , E. Scarnati5 , L. Padua2,3 , C. Erra2 , P. Mazzone6 1 Section of Neurology, Department of Medical Surgical Sciences of Communication and Behaviour, University of Ferrara, Ferrara, Italy, 2 Department of Neuroscience, Institute of Neurology, Catholic University, Rome, Italy, 3 Don C. Gnocchi Onlus Foundation, Italy, 4 Unit` a Operativa di Neurofisiopatologia, CTO, ASL RMC, Rome, Italy, 5 Department of Sciences and Biomedical Technologies, University of L’Aquila, L’Aquila, Italy, 6 Functional and Stereotactic Neurosurgery, CTO, ASL RMC, Rome, Italy Introduction: Animal models suggest that Deep Brain Stimulation of the Pedunculopontine nucleus (PPTg-DBS) can be effective in the treatment of Parkinsonian symptoms. No evidence is available on the effect of PPTg-DBS on surface electromyographiyc patterns during gait in Parkinson’s disease (PD). Objective: To evaluate the effect of PPTg-DBS on surface electromyographiyc patterns during gait in PD. Methods: We studied 3 PD patients during PPTg-DBS stimulation (“On”) and 12 hours after having switched off PPTg-DBS (“Off”). In both conditions Levodopa was not administered for 12 hours before. The patients were male with a mean age of 64 years. Patients A and B were implanted at the right side and patient C at the left side. The patients were evaluated by sEMG of vastus medialis (VM), biceps femoris (BF), tibialis anterior (TA) and gastrocnemius medialis (GM) bilaterally. We evaluated activation timing of all muscles and the TA amplitude during the late swing-early stance phase according to a previously developed protocol (Caliandro et al. 2010). Results: In “Off”, patients A and B showed a concomitant bilateral synergic contraction of VM, BF and GM during gait initiation. Patient A (implanted in the right PPTg) showed absence of the right TA activity during the late swing-early in 80% of the gait cycles and absence of the left TA in 83% of gait cycles, patient B showed absence of the right TA during the late swing-early stance in 86% of gait cycles. In “On”, the same two patients showed absence of the synergic contraction of VM, BF and GM and a bilateral normal activation of TA. It is noteworthy that in patient A the improvement of TA pattern was bilateral although the implant was monolateral. In the patient C sEMG patterns were normal in “On” and “Off”. Conclusions: Our observations support the hypothesis of gait improvement after PPTg-DBS and suggest that sEMG may represent a tool to study the bilateral consequences of a monolateral implant. P7.13 Neurophysiological assessment through visual evoked potentials and tensiomyography on multiple sclerosis patients M.C. Neamtu1 , B. Catalin1 , L. Rusu2 , T. Avramescu2 , D. Georgescu1 , A.T. Balseanu1 , O.M. Neamtu2 , M. Iancau1 1 University of Medicine and Pharmacology, Craiova, Romania, 2 University of Craiova, Craiova, Romania Introduction: Multiple sclerosis (MS) is a chronic disease, characterized by inflammatory processes at the level of central nervous system, associated with demyelinisation in axonal area. Objectives: The identification of a predictable parameters for patients with MS using TMG (tensiomyography) and VEP (Visual evoked potentials). Methods: We assesses 86 parameters, 36 parameters in VEP evaluation, 50 in TMG, both on a group of patients suffering from certain Ms (20 patients) and a control group. The MS lot was grouped in two subgroups: subgroup A, with clinically detectable gait disorders and subgroup B, without clinically detectable gait disorders. All groups were tested by neurophysiologic evaluation methods such as VEP, using a pattern reversal
14th ECCN / 4th ICTMS/DCS full field stimulation and TMG on quadriceps components, femoral biceps, gastrocnemian muscles and tibialis anterior. Results: We recorded high values of wave N75 latencies in subgroup A. The delays of the P100 wave were presented in both subgroups. In our study, the contraction time as TMG parameter recorded higher values in posterior muscular group of the thigh and anterior muscular group of the shank. After analyzing muscular displacement and relaxation time, we observed a higher muscle tonus in all muscular groups we tested, especially in gastrocnemian. The ratio direct/converse correlation is high in VEP/TMG correlations. Conclusions: We have used original testing methods for the first time in our country such as tensiomyography to explore MS patients, simultaneously completing an analysis by correlating the results of the investigations, to both create a new diagnosis algorithm and predict the evolution of balance and gait disorders at these patients. P7.14 Use of Type A botulinum toxin for chronic low back pain treatment in Parkinsonian patients R. Di Giacopo1 , A. Guidubaldi1 , T. Ialongo1 , A. Bentivoglio1 Department of Neuroscience Catholic University, Rome, Italy
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Introduction: Chronic low back pain (cLBP) is an important cause of disability in aged people. It does appear that Type A Botulinum Toxin (BoNT-A) is useful for cLBP management in those patients failing firstline treatment, specially when they have muscle tension. So the BoNT-A can represent a new possibility in Parkinson’s disease patients who often present LBP and trunk dystonia. None study investigating BoNT-A for pain treatment in this patients however exists. Objective: To evaluate the efficacy and side effect of BoNT-A for cLBP therapy in Parkinsonian patients. Methods: We enrolled 9 patients. The inclusion criteria consisted of LBP of more than six months, failure to respond to at least two major medications, ability to fill in a questionnaire; the exclusion criteria consisted of MRI showing lesion requiring urgent intervention. By electromyography, Dysport® BoNT-A was injected into the paraspinal muscles at three to four levels (between L2 and S1) bilaterally. The dose per site varied from 80 to 20 UI. Pain visual analogue scale (VAS), Oswestry Low Back Pain Questionnaire (OLBPQ) and perceived functional status (EQ-5D) were assessed at baseline, and at 1, 4 and 16 weeks after the first inoculation. Results: At 4 weeks 6/9 patients reported pain relief and reduced their analgesic therapy. The change in mean VAS and OLBPQ was significant compared to baseline and remained so over four months in 2/6 patients. 4/6 patients required re-injection after four months. No side effects were noted. Conclusions: BoNT-A seems an effective option for cLBP treatment in our cohort. Because the BoNT-A dose employed (Dysport® 240 UI) was more lower compared that utilised in literature (Botox® 200 500 UI), BoNT-A efficacy seems depending not only on normalisation of muscular hyperactivity, but also on normalisation of excessive muscle spindle activity, and inhibition of the release of neuropeptides by the nociceptor both in peripheral tissues and central nervous system P7.15 The motor and cognitive effects of extradural motor cortex stimulation for Parkinson’s disease: a 1-year prospective open-label study A.R. Bentivoglio1 , A. Fasano1 , C. Piano1 , F. Soleti1 , A. Daniele1 , M. Zinno1 , C. Piccinini1 , C. De Simone1 , T. Tufo1 , M. Meglio1 , B. Cioni1 1 Dipartimento di Neuroscienze, UCSC, Rome, Italy Introduction: Primary motor cortex is part of the cortical-basal ganglia loops, representing an “alternative” target for the surgical treatment of Parkinson’s disease (PD). To date, hundred patients have been treated with EMCS, with conflicting results. Objective: To report the motor and cognitive effects of unilateral EMCS in patients affected by PD up to 1 year after the surgical procedure. Methods: This is a prospective open-label study on PD patients with unilateral EMCS and 1 year follow-up. Surgical procedure was performed under general anaesthesia by placing over the motor cortex a quadripolar electrode strip connected to an implantable pulse generator sited in the subclavear region. Subjects were prospectively evaluated by means of PDQL (quality of life QL), UPDRS-II (daily life activities) UPDRS-III (motor section) and IV (complications of medical therapy).
S93 Results: Nine patients met the inclusion criteria. No adverse effect related to the surgical procedure or stimulation and no cognitive decline occurred. EMCS induced a marginal but significant QL improvement: baseline PDQL (81.1±17.8) was increased at month 3 (112.1±28.6; p = 0.03), month 6 (103.1±18.6; p = 0.02), and month 12 (100.7±20.5, p = 0.02). The UPDRS-II “Walking” score at month 3, 6 and 12 and “freezing of gait” at month 6 and 12 were significantly reduced as compared to baseline. In medication OFF, the total UPDRS motor score at baseline was reduced by 14.1% (p = 0.01), 23.3% (p = 0.04), 19.9% (p = 0.02), and 13.2% (p = 0.01), at month 1, 3, 6, and 12, respectively. The improvement was mostly related to the effect on axial and contralateral scores. In ON condition, EMCS failed to affect any of the outcome measurements. The UPDRS-IV total score was reduced by 40.8% (p = 0.05), 42.1% (p = 0.04) and 35.5% (p = 0.03) at month 1, 3 and 12, respectively. A significant effect on dyskinesias score emerged at month 1 and 3 as compared to baseline. The levodopa equivalent daily dose after surgery was reduced by 6.3%, 2.5%, 13.5%, and 2.5% at 1, 3, 6 and 12 months, respectively (significant at month 6, p = 0.02). Conclusion: EMCS is a safe procedure. After 12 months, the patients achieved a significant improvement of the motor condition with a specific effect on the axial performance and a slight reduction of dyskinesias, leading to a significant impact on the quality of life. P7.16 Joints kinematics and ataxia of lower limbs during walking in essential tremor is differentially modulated by thalamic stimulation A. Fasano1 , J. Herzog2 , J. Raethjen2 , F.E.M. Rose2 , M. Muthuraman2 , J. Volkmann2 , D. Falk3 , R. Elble4 , G. Deuschl2 1 Dipartimento di Neuroscienze, UCSC, Rome, Italy, 2 Department of Neurology, Christian-Albrechts-University, Kiel, Germany, 3 Department of Neurosurgery, Christian-Albrechts-University, Kiel, Germany, Kiel, Germany, 4 Department of Neurology, Southern Illinois U. School of Medicine, Springfield, United States Introduction: Patients in advanced stages of Essential Tremor (ET) regularly exhibit gait ataxia, impaired balance control and imprecise foot placement resembling patients with cerebellar deficits. Objectives: To elucidate the impact on cerebellar-like gait difficulties in ET patients of thalamic deep brain stimulation (thalamic DBS), a surgical therapy of otherwise intractable ET. Methods: Eleven ET patients (five women; age 69.8±3.9; disease duration 24.4±11.2 years; follow-up after surgery 24.7±20.3 months) were evaluated during the following conditions: stimulation off (STIM-OFF), stimulation on (STIM-ON), and supra-therapeutic stimulation (STIM-ST). Ten age-matched healthy controls (HC) served as comparison group. Locomotion was kinematically analysed using a three-dimensional optoelectronic motion analysis system. Established clinical and kinesiologic measures of ataxia were computed. Results: During STIM-OFF, the patients exhibited ataxia of foot trajectories and lower limb joints, which improved during STIM-ON and worsened again during STIM-ST. In the whole group, DBS improved ankle rotation and reduced leg stiffness (compensating the impaired dynamic stability). Moreover, in a subgroup of ET patients with more severe disease, thalamic DBS caused normalisation of kinematic variability and joint range of rotation, compared to STIM-OFF and STIM-ST. These improvements in ataxia were not a function ofrelated to reduced tremor improvement in the lower limbs or torso. Conclusion: Cerebellar dysfunction in ET patients can be differentially modulated with optimal versus supra-therapeutic stimulation. The cerebellar movement disorder of ET is due to a typical cerebellar deficit, not to trembling extremities. We hypothesize that DBS affects two major regulating circuits: the cortico-thalamo-cortical loop for tremor reduction and the cerebello-thalamo-cortical pathway for ataxia reduction (STIM-ON) and induction (STIM-ST).
1
Introduction: Neurodegenerative disorders inducing cognitive impairment include Parkinson’s disease (PD) and Alzheimer’s disease (AD). Even in the early stages of PD, cognitive deficits are found in the majority of patients even if with no impact on their global abilities within the cognitive spectrum. Objective: Does cortical source mapping of resting state electroencephalographic (EEG) rhythms characterize neurodegenerative disorders inducing cognitive impairment such as Parkinson’s disease related dementia (PDD) and AD? Methods: To address this issue, eyes-closed resting state EEG rhythms were recorded in 13 PDD, 20 AD, and 20 normal elderly (Nold) subjects. Age, gender, and education were carefully matched across the three groups. Mini mental state evaluation (MMSE) score probed subjects’ global cognitive status, and was matched between the PDD and AD groups. EEG rhythms of interest were delta (2 4 Hz), theta (4 8 Hz), alpha1 (8 10.5 Hz), alpha2 (10.5 13 Hz), beta1 (13 20 Hz), and beta2 (20 30 Hz). EEG cortical sources were estimated by low resolution brain electromagnetic source tomography (LORETA). Results: With respect to the Nold and AD groups, the PPD group was characterized by peculiar abnormalities of central delta sources and posterior cortical sources of theta and beta1 rhythms. With respect to the Nold group, the PDD and AD groups mainly pointed to lower posterior cortical sources of alpha1 rhythms, which were positively correlated to MMSE score across all PDD and AD subjects as a whole (the lower the alpha sources, the lower the MMSE score). This alpha decrease was greater in the AD than PPD patients. Conclusions: The results suggest that topography and frequency of eyesclosed resting state cortical EEG rhythms distinguished PDD and AD groups, suggesting different topographic tracks of neurodegeneration and effects on the cortical neural synchronization mechanisms generating EEG rhythms in PDD and AD patients. P7.11 Corticomuscular system tunes to external perturbations during a motor task as revealed by corticomuscular coherence S.F. Campfens1 , A.C. Schouten2 , H. van der Kooij2 , M.J.A.M. van Putten1 1 Clinical Neurophysiology, MIRA institute, University of Twente, Enschede, Netherlands, 2 Laboratory of Biomechanical Engineering, MIRA Institute, University of Twente, Enschede, Netherlands Introduction: Functional coupling between cortex and muscles during a motor task can be quantified using EEG-EMG coherence. This corticomuscular coherence (CMC) is found during a static isometric task in the beta band (15 30 Hz). The CMC serves as a measure of corticomuscular integrity. Questions that remain unanswered include the causal relation between the EEG and EMG signal and the (patho-)physiological relevance of CMC in health and various neurological conditions. Objective: In this study we investigated the effect of adding small position perturbations on the CMC during a static force task. Perturbations are necessary for closed loop system identification of the corticomuscular system. Potential clinical applications of this identification include the differential diagnosis of several movement disorders. Methods: Healthy volunteers (n = 2) were instructed to exert a constant force against the handle of a wrist manipulator with their right hand. In the baseline condition, the handle of the manipulator fixed the wrist position. In the perturbation condition the handle moved following a profile consisting of a sum of sine waves, containing power at prime frequencies between 7 and 31 Hz. CMC was estimated using nonoverlapping epochs of 2 seconds. Results: During the perturbation condition significant CMC was found at the perturbation frequencies above 11 Hz; below 11 Hz not all perturbation frequencies showed CMC. Beta band CMC present in the baseline condition was preserved during the perturbation.
Poster presentations: Poster session 7. Movement disorders
2
Conclusions: This pilot shows that the corticospinal system can tune to external perturbations during a motor task. The preservation of baseline beta band CMC during the perturbation indicates that the perturbation does not influence the system at frequencies that are not excited. The different effect of perturbations below and above 11 Hz could indicate a difference in information processing in different frequency bands, further experiments are needed to clarify this. P7.12 Unilateral pedunculopontine stimulation improves electromyographic activation patterns during gait in selected patients with Parkinson’s disease P. Caliandro1,2,3 , A. Insola3,4 , E. Scarnati5 , L. Padua2,3 , C. Erra2 , P. Mazzone6 1 Section of Neurology, Department of Medical Surgical Sciences of Communication and Behaviour, University of Ferrara, Ferrara, Italy, 2 Department of Neuroscience, Institute of Neurology, Catholic University, Rome, Italy, 3 Don C. Gnocchi Onlus Foundation, Italy, 4 Unit` a Operativa di Neurofisiopatologia, CTO, ASL RMC, Rome, Italy, 5 Department of Sciences and Biomedical Technologies, University of L’Aquila, L’Aquila, Italy, 6 Functional and Stereotactic Neurosurgery, CTO, ASL RMC, Rome, Italy Introduction: Animal models suggest that Deep Brain Stimulation of the Pedunculopontine nucleus (PPTg-DBS) can be effective in the treatment of Parkinsonian symptoms. No evidence is available on the effect of PPTg-DBS on surface electromyographiyc patterns during gait in Parkinson’s disease (PD). Objective: To evaluate the effect of PPTg-DBS on surface electromyographiyc patterns during gait in PD. Methods: We studied 3 PD patients during PPTg-DBS stimulation (“On”) and 12 hours after having switched off PPTg-DBS (“Off”). In both conditions Levodopa was not administered for 12 hours before. The patients were male with a mean age of 64 years. Patients A and B were implanted at the right side and patient C at the left side. The patients were evaluated by sEMG of vastus medialis (VM), biceps femoris (BF), tibialis anterior (TA) and gastrocnemius medialis (GM) bilaterally. We evaluated activation timing of all muscles and the TA amplitude during the late swing-early stance phase according to a previously developed protocol (Caliandro et al. 2010). Results: In “Off”, patients A and B showed a concomitant bilateral synergic contraction of VM, BF and GM during gait initiation. Patient A (implanted in the right PPTg) showed absence of the right TA activity during the late swing-early in 80% of the gait cycles and absence of the left TA in 83% of gait cycles, patient B showed absence of the right TA during the late swing-early stance in 86% of gait cycles. In “On”, the same two patients showed absence of the synergic contraction of VM, BF and GM and a bilateral normal activation of TA. It is noteworthy that in patient A the improvement of TA pattern was bilateral although the implant was monolateral. In the patient C sEMG patterns were normal in “On” and “Off”. Conclusions: Our observations support the hypothesis of gait improvement after PPTg-DBS and suggest that sEMG may represent a tool to study the bilateral consequences of a monolateral implant. P7.13 Neurophysiological assessment through visual evoked potentials and tensiomyography on multiple sclerosis patients M.C. Neamtu1 , B. Catalin1 , L. Rusu2 , T. Avramescu2 , D. Georgescu1 , A.T. Balseanu1 , O.M. Neamtu2 , M. Iancau1 1 University of Medicine and Pharmacology, Craiova, Romania, 2 University of Craiova, Craiova, Romania Introduction: Multiple sclerosis (MS) is a chronic disease, characterized by inflammatory processes at the level of central nervous system, associated with demyelinisation in axonal area. Objectives: The identification of a predictable parameters for patients with MS using TMG (tensiomyography) and VEP (Visual evoked potentials). Methods: We assesses 86 parameters, 36 parameters in VEP evaluation, 50 in TMG, both on a group of patients suffering from certain Ms (20 patients) and a control group. The MS lot was grouped in two subgroups: subgroup A, with clinically detectable gait disorders and subgroup B, without clinically detectable gait disorders. All groups were tested by neurophysiologic evaluation methods such as VEP, using a pattern reversal
14th ECCN / 4th ICTMS/DCS full field stimulation and TMG on quadriceps components, femoral biceps, gastrocnemian muscles and tibialis anterior. Results: We recorded high values of wave N75 latencies in subgroup A. The delays of the P100 wave were presented in both subgroups. In our study, the contraction time as TMG parameter recorded higher values in posterior muscular group of the thigh and anterior muscular group of the shank. After analyzing muscular displacement and relaxation time, we observed a higher muscle tonus in all muscular groups we tested, especially in gastrocnemian. The ratio direct/converse correlation is high in VEP/TMG correlations. Conclusions: We have used original testing methods for the first time in our country such as tensiomyography to explore MS patients, simultaneously completing an analysis by correlating the results of the investigations, to both create a new diagnosis algorithm and predict the evolution of balance and gait disorders at these patients. P7.14 Use of Type A botulinum toxin for chronic low back pain treatment in Parkinsonian patients R. Di Giacopo1 , A. Guidubaldi1 , T. Ialongo1 , A. Bentivoglio1 Department of Neuroscience Catholic University, Rome, Italy
1
Introduction: Chronic low back pain (cLBP) is an important cause of disability in aged people. It does appear that Type A Botulinum Toxin (BoNT-A) is useful for cLBP management in those patients failing firstline treatment, specially when they have muscle tension. So the BoNT-A can represent a new possibility in Parkinson’s disease patients who often present LBP and trunk dystonia. None study investigating BoNT-A for pain treatment in this patients however exists. Objective: To evaluate the efficacy and side effect of BoNT-A for cLBP therapy in Parkinsonian patients. Methods: We enrolled 9 patients. The inclusion criteria consisted of LBP of more than six months, failure to respond to at least two major medications, ability to fill in a questionnaire; the exclusion criteria consisted of MRI showing lesion requiring urgent intervention. By electromyography, Dysport® BoNT-A was injected into the paraspinal muscles at three to four levels (between L2 and S1) bilaterally. The dose per site varied from 80 to 20 UI. Pain visual analogue scale (VAS), Oswestry Low Back Pain Questionnaire (OLBPQ) and perceived functional status (EQ-5D) were assessed at baseline, and at 1, 4 and 16 weeks after the first inoculation. Results: At 4 weeks 6/9 patients reported pain relief and reduced their analgesic therapy. The change in mean VAS and OLBPQ was significant compared to baseline and remained so over four months in 2/6 patients. 4/6 patients required re-injection after four months. No side effects were noted. Conclusions: BoNT-A seems an effective option for cLBP treatment in our cohort. Because the BoNT-A dose employed (Dysport® 240 UI) was more lower compared that utilised in literature (Botox® 200 500 UI), BoNT-A efficacy seems depending not only on normalisation of muscular hyperactivity, but also on normalisation of excessive muscle spindle activity, and inhibition of the release of neuropeptides by the nociceptor both in peripheral tissues and central nervous system P7.15 The motor and cognitive effects of extradural motor cortex stimulation for Parkinson’s disease: a 1-year prospective open-label study A.R. Bentivoglio1 , A. Fasano1 , C. Piano1 , F. Soleti1 , A. Daniele1 , M. Zinno1 , C. Piccinini1 , C. De Simone1 , T. Tufo1 , M. Meglio1 , B. Cioni1 1 Dipartimento di Neuroscienze, UCSC, Rome, Italy Introduction: Primary motor cortex is part of the cortical-basal ganglia loops, representing an “alternative” target for the surgical treatment of Parkinson’s disease (PD). To date, hundred patients have been treated with EMCS, with conflicting results. Objective: To report the motor and cognitive effects of unilateral EMCS in patients affected by PD up to 1 year after the surgical procedure. Methods: This is a prospective open-label study on PD patients with unilateral EMCS and 1 year follow-up. Surgical procedure was performed under general anaesthesia by placing over the motor cortex a quadripolar electrode strip connected to an implantable pulse generator sited in the subclavear region. Subjects were prospectively evaluated by means of PDQL (quality of life QL), UPDRS-II (daily life activities) UPDRS-III (motor section) and IV (complications of medical therapy).
S93 Results: Nine patients met the inclusion criteria. No adverse effect related to the surgical procedure or stimulation and no cognitive decline occurred. EMCS induced a marginal but significant QL improvement: baseline PDQL (81.1±17.8) was increased at month 3 (112.1±28.6; p = 0.03), month 6 (103.1±18.6; p = 0.02), and month 12 (100.7±20.5, p = 0.02). The UPDRS-II “Walking” score at month 3, 6 and 12 and “freezing of gait” at month 6 and 12 were significantly reduced as compared to baseline. In medication OFF, the total UPDRS motor score at baseline was reduced by 14.1% (p = 0.01), 23.3% (p = 0.04), 19.9% (p = 0.02), and 13.2% (p = 0.01), at month 1, 3, 6, and 12, respectively. The improvement was mostly related to the effect on axial and contralateral scores. In ON condition, EMCS failed to affect any of the outcome measurements. The UPDRS-IV total score was reduced by 40.8% (p = 0.05), 42.1% (p = 0.04) and 35.5% (p = 0.03) at month 1, 3 and 12, respectively. A significant effect on dyskinesias score emerged at month 1 and 3 as compared to baseline. The levodopa equivalent daily dose after surgery was reduced by 6.3%, 2.5%, 13.5%, and 2.5% at 1, 3, 6 and 12 months, respectively (significant at month 6, p = 0.02). Conclusion: EMCS is a safe procedure. After 12 months, the patients achieved a significant improvement of the motor condition with a specific effect on the axial performance and a slight reduction of dyskinesias, leading to a significant impact on the quality of life. P7.16 Joints kinematics and ataxia of lower limbs during walking in essential tremor is differentially modulated by thalamic stimulation A. Fasano1 , J. Herzog2 , J. Raethjen2 , F.E.M. Rose2 , M. Muthuraman2 , J. Volkmann2 , D. Falk3 , R. Elble4 , G. Deuschl2 1 Dipartimento di Neuroscienze, UCSC, Rome, Italy, 2 Department of Neurology, Christian-Albrechts-University, Kiel, Germany, 3 Department of Neurosurgery, Christian-Albrechts-University, Kiel, Germany, Kiel, Germany, 4 Department of Neurology, Southern Illinois U. School of Medicine, Springfield, United States Introduction: Patients in advanced stages of Essential Tremor (ET) regularly exhibit gait ataxia, impaired balance control and imprecise foot placement resembling patients with cerebellar deficits. Objectives: To elucidate the impact on cerebellar-like gait difficulties in ET patients of thalamic deep brain stimulation (thalamic DBS), a surgical therapy of otherwise intractable ET. Methods: Eleven ET patients (five women; age 69.8±3.9; disease duration 24.4±11.2 years; follow-up after surgery 24.7±20.3 months) were evaluated during the following conditions: stimulation off (STIM-OFF), stimulation on (STIM-ON), and supra-therapeutic stimulation (STIM-ST). Ten age-matched healthy controls (HC) served as comparison group. Locomotion was kinematically analysed using a three-dimensional optoelectronic motion analysis system. Established clinical and kinesiologic measures of ataxia were computed. Results: During STIM-OFF, the patients exhibited ataxia of foot trajectories and lower limb joints, which improved during STIM-ON and worsened again during STIM-ST. In the whole group, DBS improved ankle rotation and reduced leg stiffness (compensating the impaired dynamic stability). Moreover, in a subgroup of ET patients with more severe disease, thalamic DBS caused normalisation of kinematic variability and joint range of rotation, compared to STIM-OFF and STIM-ST. These improvements in ataxia were not a function ofrelated to reduced tremor improvement in the lower limbs or torso. Conclusion: Cerebellar dysfunction in ET patients can be differentially modulated with optimal versus supra-therapeutic stimulation. The cerebellar movement disorder of ET is due to a typical cerebellar deficit, not to trembling extremities. We hypothesize that DBS affects two major regulating circuits: the cortico-thalamo-cortical loop for tremor reduction and the cerebello-thalamo-cortical pathway for ataxia reduction (STIM-ON) and induction (STIM-ST).