Journal of Neurology, Neurosurgery & Psychiatry, 2009
Microelectrode recording (MER) and macrostimulation (test stimulation) are used to refine the opt... more Microelectrode recording (MER) and macrostimulation (test stimulation) are used to refine the optimal deep brain stimulation (DBS) lead placement within the operative setting. It is well known that there can be a microlesion effect with microelectrode trajectories and DBS insertion. The aim of this study was to determine the impact of intraoperative MER and lead placement on tremor severity in a cohort of patients with essential tremor. Consecutive patients with essential tremor undergoing unilateral DBS (ventral intermediate nucleus stimulation) for medication-refractory tremor were evaluated. Tremor severity was measured at 5 time points utilizing a modified Tremor Rating Scale: 1) immediately before MER; 2) immediately after MER; 3) immediately after lead implantation; 4) 6 months after DBS implantation in the off-DBS condition; and 5) 6 months after implantation in the on-DBS condition. To investigate the impact of the MER and DBS lead placement, Wilcoxon signed-rank tests were applied to test changes in tremor severity scores over the surgical course. In addition, a generalized linear mixed model including factors that potentially influenced the impact of the microlesion was also used for analysis. Nineteen patients were evaluated. Improvement was noted in the total modified Tremor Rating Scale, postural, and action tremor scores (p < 0.05) as a result of MER and DBS lead placement. The improvements observed following lead placement were similar in magnitude to what was observed in the chronically programmed clinic setting parameters at 6 months after lead implantation. Improvement in tremor severity was maintained over time even in the off-DBS condition at 6 months, which was supportive of a prolonged microlesion effect. The number of macrostimulation passes, the number of MER passes, and disease duration were not related to the change in tremor severity score over time. Immediate improvement in postural and intention tremors may result from MER and DBS lead placement in patients undergoing DBS for essential tremor. This improvement could be a predictor of successful DBS lead placement at 6 months. Clinicians rating patients in the operating room should be aware of these effects and should consider using rating scales before and after lead placement to take these effects into account when evaluating outcome in and out of the operating room.
Medical science monitor: international medical journal of experimental and clinical research
Prior reports have suggested that low educational attainment could be associated with higher inci... more Prior reports have suggested that low educational attainment could be associated with higher incidence of some of the cardiovascular conditions. We evaluated the association of educational attainment (> or =12 years or <12 years) with the incidence of fatal strokes, ischemic stroke, intracerebral hemorrhage, and myocardial infarction in a cohort of 21,443 United States adults who participated in either the First National Health and Nutrition Examination Survey (NHANES-I) Epidemiologic Follow-up Study (NHEFS) or the Second National Health and Nutrition Examination Survey Mortality Follow-up Study (NHANES-II). Cox proportional hazards analyses were used to examine the relationships. During a mean follow-up period of 15.2+/-4.6 years, the risk for all fatal strokes was increased in persons who reported less than 12 years of education. The increased risk was more prominent in persons aged 50 years or less (relative risk [RR], 2.6; 95% confidence interval [CI], 1.1-6.0) compared wi...
Deep Brain Stimulation in Neurological and Psychiatric Disorders, 2008
... and Neuropsychiatric Disorders Mustafa Saad Siddiqui, Thomas Ellis, Stephen S. Tatter, Kelly ... more ... and Neuropsychiatric Disorders Mustafa Saad Siddiqui, Thomas Ellis, Stephen S. Tatter, Kelly D. Foote, and Michael S. Okun 83 ... Postoperative symptoms of depression, mania, anxiety, panic, and apathy have been described (30, 33, 34, 37). ...
Deep brain stimulation (DBS) is used for advanced and medically intractable patients with Parkins... more Deep brain stimulation (DBS) is used for advanced and medically intractable patients with Parkinson&amp;amp;amp;amp;amp;amp;#39;s disease (PD), essential tremor (ET), and dystonia who meet strict criteria after a detailed motor, cognitive, and psychiatric evaluation. The potential targets are the ventral intermediate nucleus (VIM) of the thalamus for tremor, the globus pallidus interna (GPI) and the subthalamic nucleus (STN) for PD, and GPI for dystonia. The optimal target for PD has not been determined yet, although STN DBS has been performed more frequently in recent years. The mechanism of DBS effect is believed to be associated with disruption of pathological network activity in the cortico-basal ganglia-thalamic circuits by affecting the firing rates and bursting patterns of neurons and synchronized oscillatory activity of neuronal networks. Good candidates should be free of dementia, major psychiatric disorders, structural brain lesions, and important general medical problems. Although the risk for complications with DBS is less than with lesioning techniques, there is still a small risk for major complications associated with surgery. Bilateral procedures are more likely to cause problems with speech, cognition, and gait.
Journal of Neurology, Neurosurgery & Psychiatry, 2009
Microelectrode recording (MER) and macrostimulation (test stimulation) are used to refine the opt... more Microelectrode recording (MER) and macrostimulation (test stimulation) are used to refine the optimal deep brain stimulation (DBS) lead placement within the operative setting. It is well known that there can be a microlesion effect with microelectrode trajectories and DBS insertion. The aim of this study was to determine the impact of intraoperative MER and lead placement on tremor severity in a cohort of patients with essential tremor. Consecutive patients with essential tremor undergoing unilateral DBS (ventral intermediate nucleus stimulation) for medication-refractory tremor were evaluated. Tremor severity was measured at 5 time points utilizing a modified Tremor Rating Scale: 1) immediately before MER; 2) immediately after MER; 3) immediately after lead implantation; 4) 6 months after DBS implantation in the off-DBS condition; and 5) 6 months after implantation in the on-DBS condition. To investigate the impact of the MER and DBS lead placement, Wilcoxon signed-rank tests were applied to test changes in tremor severity scores over the surgical course. In addition, a generalized linear mixed model including factors that potentially influenced the impact of the microlesion was also used for analysis. Nineteen patients were evaluated. Improvement was noted in the total modified Tremor Rating Scale, postural, and action tremor scores (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05) as a result of MER and DBS lead placement. The improvements observed following lead placement were similar in magnitude to what was observed in the chronically programmed clinic setting parameters at 6 months after lead implantation. Improvement in tremor severity was maintained over time even in the off-DBS condition at 6 months, which was supportive of a prolonged microlesion effect. The number of macrostimulation passes, the number of MER passes, and disease duration were not related to the change in tremor severity score over time. Immediate improvement in postural and intention tremors may result from MER and DBS lead placement in patients undergoing DBS for essential tremor. This improvement could be a predictor of successful DBS lead placement at 6 months. Clinicians rating patients in the operating room should be aware of these effects and should consider using rating scales before and after lead placement to take these effects into account when evaluating outcome in and out of the operating room.
Medical science monitor: international medical journal of experimental and clinical research
Prior reports have suggested that low educational attainment could be associated with higher inci... more Prior reports have suggested that low educational attainment could be associated with higher incidence of some of the cardiovascular conditions. We evaluated the association of educational attainment (> or =12 years or <12 years) with the incidence of fatal strokes, ischemic stroke, intracerebral hemorrhage, and myocardial infarction in a cohort of 21,443 United States adults who participated in either the First National Health and Nutrition Examination Survey (NHANES-I) Epidemiologic Follow-up Study (NHEFS) or the Second National Health and Nutrition Examination Survey Mortality Follow-up Study (NHANES-II). Cox proportional hazards analyses were used to examine the relationships. During a mean follow-up period of 15.2+/-4.6 years, the risk for all fatal strokes was increased in persons who reported less than 12 years of education. The increased risk was more prominent in persons aged 50 years or less (relative risk [RR], 2.6; 95% confidence interval [CI], 1.1-6.0) compared wi...
Deep Brain Stimulation in Neurological and Psychiatric Disorders, 2008
... and Neuropsychiatric Disorders Mustafa Saad Siddiqui, Thomas Ellis, Stephen S. Tatter, Kelly ... more ... and Neuropsychiatric Disorders Mustafa Saad Siddiqui, Thomas Ellis, Stephen S. Tatter, Kelly D. Foote, and Michael S. Okun 83 ... Postoperative symptoms of depression, mania, anxiety, panic, and apathy have been described (30, 33, 34, 37). ...
Deep brain stimulation (DBS) is used for advanced and medically intractable patients with Parkins... more Deep brain stimulation (DBS) is used for advanced and medically intractable patients with Parkinson&amp;amp;amp;amp;amp;amp;#39;s disease (PD), essential tremor (ET), and dystonia who meet strict criteria after a detailed motor, cognitive, and psychiatric evaluation. The potential targets are the ventral intermediate nucleus (VIM) of the thalamus for tremor, the globus pallidus interna (GPI) and the subthalamic nucleus (STN) for PD, and GPI for dystonia. The optimal target for PD has not been determined yet, although STN DBS has been performed more frequently in recent years. The mechanism of DBS effect is believed to be associated with disruption of pathological network activity in the cortico-basal ganglia-thalamic circuits by affecting the firing rates and bursting patterns of neurons and synchronized oscillatory activity of neuronal networks. Good candidates should be free of dementia, major psychiatric disorders, structural brain lesions, and important general medical problems. Although the risk for complications with DBS is less than with lesioning techniques, there is still a small risk for major complications associated with surgery. Bilateral procedures are more likely to cause problems with speech, cognition, and gait.
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