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Test Stimulation (test + stimulation)
Selected AbstractsAntiepileptogenic and antiictogenic effects of retigabine under conditions of rapid kindling: An ontogenic studyEPILEPSIA, Issue 10 2008Andréy Mazarati Summary Purpose:, To examine antiepileptogenic and antiictogenic potential of retigabine (RTG) under conditions of rapid kindling epileptogenesis during different stages of development. Methods:, The experiments were performed in postnatal day 14 (P14), P21, and P35 male Wistar rats. After stereotaxic implantation of hippocampal stimulating and recording electrodes, the effects of RTG on baseline afterdischarge (AD) properties were studied. Next, the animals underwent rapid kindling (sixty 10 s trains, bipolar 20 Hz square wave pulses delivered every 5 min). The progression of seizures (kindling acquisition), and responses to test stimulations after kindling (retention) were compared between RTG and vehicle-treated rats. Additionally, the effects of RTG on the severity of seizures in previously kindled animals were examined. Results:, When administered intraperitoneally in doses that induced only mild, or no motor deficits, RTG significantly dampened brain excitability, evident as the increase of AD threshold and shortening of AD duration. During kindling, RTG delayed the development of focal seizures in P14 rats, and prevented the occurrence of full limbic seizures at all three ages. At P14 and P21, but not at P35, pretreatment with RTG prevented the establishment of kindling-induced enhanced seizure susceptibility. Administration of RTG to kindled animals decreased the severity of seizures induced by test stimulation. The effect was most prominent at P14. Discussion:, RTG exerted both antiepileptogenic and antiictogenic effects under conditions of rapid kindling model. These effects were apparent during postneonatal, early childhood, and adolescent stages of development. [source] The serotonin 5-HT2 receptor,phospholipase C system inhibits the induction of long-term potentiation in the rat visual cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2000Yoshikuni Edagawa Abstract The effect of serotonin 5-HT2 receptor stimulation on long-term potentiation (LTP) in the primary visual cortex was investigated by using rat brain slices in vitro. Field potentials evoked by stimulation of layer IV were recorded in layer II/III. The 5-HT2 receptor agonist 1-(2,5-dimethyl-4-iodophenyl)-2-aminopropane (DOI) did not affect baseline synaptic potentials evoked by single-pulse test stimulation, but significantly inhibited the induction of LTP in a concentration-dependent manner (0.1,10 ,m). The LTP-inhibiting effect of DOI (10 ,m) was blocked by the 5-HT2,7 receptor antagonist ritanserin (10 ,m), but not by the 5-HT1A receptor antagonist NAN-190 (10 ,m) nor by the 5-HT3,4 receptor antagonist MDL72222 (10 ,m). The inhibitory effect of DOI was also blocked by the phospholipase C inhibitor U73122, but not by its inactive analogue U73343. These results suggest that visual cortex LTP is inhibited by activation of the 5-HT2 receptor,phospholipase C system. In addition, the LTP-inhibiting effect of DOI was abolished by the presence of the GABAA receptor antagonist bicuculline (10 ,m), suggesting that 5-HT2 receptor-mediated inhibition of visual cortex LTP is dependent on GABAergic inhibition. [source] Predicting implantation with a neuromodulator using two different test stimulation techniques: A prospective randomized study in urge incontinent women,NEUROUROLOGY AND URODYNAMICS, Issue 1 2007Kristy M. Borawski MD Abstract Aims The purpose of this study was to determine whether a percutaneous needle electrode (PNE) technique or a surgical first stage lead placement (FSLP) better predicted whether a patient would progress to implantation of a pulse generator (IPG) in older urge incontinent women. Methods Thirty subjects ,55 years with refractory urge incontinence who had been selected to undergo a test stimulation procedure were randomized to either PNE or FSLP. Thirteen underwent PNE placement and seventeen underwent FSLP placement. If during the test stimulation period subjects had greater than 50% improvement in their incontinence parameters they qualified for permanent lead and/or IPG implantation of the Interstim® device. Results Twenty-one subjects (70%) responded to the test stimulation and underwent implantation, 15/17 (88%) in the FSLP group and 6/13 (46%) in the PNE group. Subjects who were randomized to the FSLP group were significantly more likely to proceed to implantation of the IPG (P,=,0.02) than those in the PNE group. There was no significant difference in demographics, pre-test stimulation incontinence parameters or post-stimulation visual analog pain scores between the randomized groups or between test stimulation responders and non-responders. When comparing FSLP and PNE responders, there was no significant difference in the percent improvement in 24-hr pad weight, daily pad usage, or daily incontinence. Conclusion FSLP better predicted progression to implantation of the IPG than a test stimulation with a PNE in an older urge incontinent cohort. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] The effect of spinal cord stimulation in patients with chronic reflex sympathetic dystrophy: Two years' follow-up of the randomized controlled trialANNALS OF NEUROLOGY, Issue 1 2004Marius A. Kemler MD Chronic reflex sympathetic dystrophy is a painful, disabling disorder for which no treatment with proven effect is available. We performed a randomized trial in a 2 to 1 ratio of patients, in which 36 patients were treated with spinal cord stimulation and physical therapy (SCS+PT), and 18 patients received solely PT. Twenty-four SCS+PT patients were given a permanent spinal cord stimulation system after successful test stimulation; the remaining 12 patients received no permanent system. We assessed pain intensity, global perceived effect, functional status, and health-related quality of life. Patients were examined before randomization, before implantation, and also at 1, 3, 6, 12, and 24 months thereafter. At 2 years, three patients were excluded from the analysis. The intention-to-treat analysis showed improvements in the SCS+PT group concerning pain intensity (,2.1 vs 0.0cm; p < 0.001) and global perceived effect (43% vs 6% "much improved"; p = 0.001). There was no clinically important improvement of functional status. Health-related quality of life improved only in the group receiving spinal cord stimulation. After careful selection and successful test stimulation, spinal cord stimulation results in a long-term pain reduction and health-related quality of life improvement in chronic reflex sympathetic dystrophy. [source] Sacral nerve modulation and other treatments in patients with faecal incontinence after unsuccessful pelvic floor rehabilitation: a prospective studyCOLORECTAL DISEASE, Issue 4 2010S. M. Koch Abstract Objectives Sacral nerve modulation (SNM) is a minimally invasive technique for the treatment of faecal incontinence. This study investigates the results of SNM after negative outcome of a standardized pelvic floor rehabilitation (PFR) programme for the treatment of faecal incontinence. Method, A prospective cohort study was performed between December 2001 and August 2007. Consecutive patients who visited the outpatient department for faecal incontinence were included in a multicentre study and treated with standardized PFR. Those with an unsuccessful result who were eligible for SNM were included in the present study. Failures at test stimulation or SNM received another treatment. Clinical outcome, Vaizey scores and Hirschsprung's disease/anorectal malformation quality-of-life (EQ-5D and HAQL) were assessed during follow-up in patients with SNM and in patients with other treatments (OT). Adverse events (AE) were documented. Results, Thirty-five patients (mean age 59.7 years; 31 females) were included. Twenty-one had a successful test stimulation and 19 patients proceeded to a SNM implant. Incontinence episodes per week decreased significantly from 11.1 ± 11.7 to 1.9 ± 2.6 during test stimulation (P < 0.0001) and SNM over 24.1 months follow-up. The overall success rate was 49% (17/35). The patients with unsuccessful test stimulation or SNM received OT. The Vaizey score improved in both SNM (18.2 ± 3.5 vs 13.7 ± 4.8; P = 0.004) and other treatment (18.2 ± 3.5 vs 13.9 ± 6.9; P = 0.019). The HAQL scale improved significantly during SNM in all subscales (P < 0.005), but not in the other treatment group. Eight AE occurred during test stimulation (23%) and six AE after permanent implantation (26%). Conclusion, Sacral nerve modulation improves disease specific quality of life significantly compared with other treatment. [source] Is a morphologically intact anal sphincter necessary for success with sacral nerve modulation in patients with faecal incontinence?COLORECTAL DISEASE, Issue 3 2008J. Melenhorst Abstract Objective, Sacral nerve modulation (SNM) for the treatment of faecal incontinence was originally performed in patients with an intact anal sphincter or after repair of a sphincter defect. There is evidence that SNM can be performed in patients with faecal incontinence and an anal sphincter defect. Method, Two groups of patients were analysed retrospectively to determine whether SNM is as effective in patients with faecal incontinence associated with an anal sphincter defect as in those with a morphologically intact anal sphincter following anal repair (AR). Patients in group A had had an AR resulting in an intact anal sphincter ring. Group B included patients with a sphincter defect which was not primarily repaired. Both groups underwent SNM. All patients had undergone a test stimulation percutaneous nerve evaluation (PNE) followed by a subchronic test over 3 weeks. If the PNE was successful, a permanent SNM electrode was implanted. Follow-up visits for the successfully permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter. Results, Group A consisted of 20 (19 women) patients. Eighteen (90%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. Group B consisted of 20 women. The size of the defect in the anal sphincter varied between 17% and 33% of the anal circumference. Fourteen (70%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. In both groups, the mean number of incontinence episodes decreased significantly with SNM (test vs baseline: P = 0.0001, P = 0.0002). There was no significant difference in resting and squeeze pressures during SNM in group A, but in group B squeeze pressure had increased significantly at 24 months. Comparison of patient characteristics and outcome between groups A and B revealed no statistical differences. Conclusion, A morphologically intact anal sphincter is not a prerequisite for success in the treatment of faecal incontinence with SNM. An anal sphincter defect of <33% of the circumference can be effectively treated primarily with SNM without repair. [source] Sacral neuromodulation in patients with faecal incontinence: results of the first 100 permanent implantationsCOLORECTAL DISEASE, Issue 8 2007J. Melenhorst Abstract Objective, Faecal incontinence (FI) is a socially devastating problem. Sacral nerve modulation (SNM) has proven its place in the treatment of patients with FI. In this study, the first 100 definitive SNM implants in a single centre have been evaluated prospectively. Method, Patients treated between March 2000 and May 2005 were included. Faecal incontinence was defined as at least one episode of involuntary faecal loss per week confirmed by a 3-week bowel habit diary. Patients were eligible for implantation of a permanent SNM when showing at least a 50% reduction in incontinence episodes or days during ambulatory test stimulation. Preoperative workup consisted of an X-defaecography, pudendal nerve terminal motor latency measurement, endo-anal ultrasound and anal manometry. The follow-up visits for the permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter. The bowel habit diary and anal manometry were repeated postoperatively during the follow-up visits. Results, A total of 134 patients were included and received a subchronic test stimulation. One hundred patients (74.6%) had a positive test stimulation and received a definitive SNM implantation. The permanent implantation group consisted of 89 women and 11 men. The mean age was 55 years (range 26,75). The mean follow-up was 25.5 months (range 2.5,63.2). The mean number of incontinence episodes decreased significantly during the test stimulation (baseline, 31.3; test, 4.4; P < 0.0001) and at follow-up (36 months postoperatively, 4.8; P < 0.0001). There was no significant change in the mean anal resting pressure. The squeeze pressures were significantly higher at 6 months (109.8 mmHg; P = 0.03), 12 months (114.1 mmHg; P = 0.02) and 24 months postoperatively (113.5 mmHg; P = 0.007). The first sensation, urge and maximum tolerable volume did not change significantly. Twenty-one patients were considered late failures and received further treatment. Conclusion, Sacral neuromodulation is an effective treatment for FI. The medium-term results were satisfying. [source] Seizure Suppression by Adenosine-releasing Cells Is Independent of Seizure FrequencyEPILEPSIA, Issue 8 2002Detlev Boison Summary: ,Purpose: Intraventricular cellular delivery of adenosine was recently shown to be transiently efficient in the suppression of seizure activity in the rat kindling model of epilepsy. We tested whether the suppression of seizures by adenosine-releasing grafts was independent of seizure frequency. Methods: Adenosine-releasing cells were encapsulated and grafted into the lateral brain ventricle of rats kindled in the hippocampus. During 4 weeks after grafting, electric test stimulations were delivered at a frequency of either once a week or 3 times per week. Seizure activity was evaluated by visual scoring of seizure severity and by the recording of EEGs. Results: Adenosine released from encapsulated cells exerted potent antiepileptic activity for ,2 weeks. One week after grafting, treated rats displayed a complete protection from clonic seizures, and a protection from focal seizures was observed in the majority of animals. Seizure suppression was accompanied by a reduction of afterdischarges in EEG recordings. The protective efficacy of the grafted cells was the same irrespective of whether electrical test stimulations were delivered 1 or 3 times per week. Rats receiving control grafts continued to display full clonic convulsions. Conclusions: This study demonstrated that the frequency of test stimulations did not influence the seizure-suppressive potential of adenosine-releasing grafts. Thus the local delivery of adenosine is likely to be effective in seizure control over a threefold range of seizure-discharge frequency. [source] | ||||||||||