SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Fytagoridis Anders) "

Sökning: WFRF:(Fytagoridis Anders)

  • Resultat 1-10 av 23
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Agren, Richard, et al. (författare)
  • Pulse Width and Implantable Pulse Generator Longevity in Pallidal Deep Brain Stimulation for Dystonia : A Population-Based Comparative Effectiveness Study
  • 2020
  • Ingår i: Stereotactic and Functional Neurosurgery. - : S. Karger. - 1011-6125 .- 1423-0372. ; 98:5, s. 331-336
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: A wide range of pulse widths (PWs) has been used in globus pallidus internus (GPi) deep brain stimulation (DBS) for dystonia. However, no specific PW has demonstrated clinical superiority, and the paradigm may differ among DBS centers.Objective: To investigate how different paradigms of PWs in GPi DBS for dystonia affect implantable pulse generator (IPG) longevities and energy consumption.Methods: Thirty-nine patients with dystonia treated with bilateral GPi DBS at 2 Swedish DBS centers from 2005 to 2015 were included. Different PW paradigms were used at the 2 centers, 60–90 µs (short PWs) and 450 µs (long PW), respectively. The frequency of IPG replacements, pulse effective voltage (PEV), IPG model, pre-/postoperative imaging, and clinical outcome based on the clinical global impression (CGI) scale were collected from the medical charts and compared between the 2 groups.Results: The average IPG longevity was extended for the short PWs (1,129 ± 50 days) compared to the long PW (925 ± 32 days; χ2 = 12.31, p = 0.0005, log-rank test). IPG longevity correlated inversely with PEV (Pearson’s r = –0.667, p < 0.0001). IPG longevities did not differ between Kinetra® and Activa® PC in the short (p = 0.319) or long PW group (p = 0.858). Electrode distances to the central sensorimotor region of the GPi did not differ between the short or long PW groups (p = 0.595). Pre- and postoperative CGI did not differ between groups.Conclusions: Short PWs were associated with decreased energy consumption and increased IPG longevity. These effects were not dependent on the IPG model or the anatomic location of the electrodes. PWs did not correlate with symptom severities or clinical outcomes. The results suggest that the use of short PWs might be more energy efficient and could therefore be preferred initially when programming patients with GPi DBS for dystonia.
  •  
2.
  • Blomstedt, Patric, et al. (författare)
  • Deep brain stimulation of the posterior subthalamic area in the treatment of tremor
  • 2009
  • Ingår i: Acta Neurochirurgica. - : Springer Science and Business Media LLC. - 0001-6268 .- 0942-0940. ; 151:1, s. 31-36
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Several studies have described lesional therapy in the posterior subthalamic area (PSA) in the treatment of various movement disorders. Recently, some publications have illustrated the effect of deep brain stimulation (DBS) in this area in patients with Parkinson's disease, essential tremor, MS-tremor, and other forms of tremor. Even though the clinical series is small, the reported benefits prompted us to explore DBS in this area in the treatment of tremor. METHOD: Five patients with tremor were operated using unilateral DBS of the PSA. Two patients had dystonic tremor, one primary writing tremor, one cerebellar tremor and the other neuropathic tremor. All patients were assessed before and 1 year after surgery using items 5 and 6 (tremor of the upper extremity), 11-14 (hand function), and when appropriate item 10 (handwriting) from the essential tremor rating scale. FINDINGS: The mean improvement on stimulation after 1 year was 87%. A pronounced and sustained microlesional effect was seen in several of the patients, and while the mean improvement off stimulation was 56% the reduction in the three patients with the most pronounced effect was 89%. The two patients with dystonic tremor did also become free of the dystonic symptoms and pain in the treated arm. No severe complication occurred. CONCLUSIONS: DBS of the PSA in this small group of patients had an excellent effect on the different forms of tremor, except for the neuropathic tremor where the effect was moderate. These preliminary results suggest PSA to be an effective target for the treatment of various forms of tremor. Further studies concerning indications, safety and efficacy of DBS in the posterior subthalamic area are required.
  •  
3.
  • Blomstedt, Patric, et al. (författare)
  • Influence of age, gender and severity of tremor on outcome after thalamic and subthalamic DBS for essential tremor
  • 2011
  • Ingår i: Parkinsonism & Related Disorders. - : Elsevier BV. - 1353-8020 .- 1873-5126. ; 17:8, s. 617-620
  • Tidskriftsartikel (refereegranskat)abstract
    • Deep brain stimulation (DBS) is an established treatment for essential tremor (ET). The nucleus ventralis intermedius thalami (Vim) is the target of choice, but promising results have been presented regarding DBS in the posterior subthalamic area (PSA). The aim of this study was to evaluate the possible influence of gender, age and severity of disease on the outcome of these procedures. Sixty eight patients (34 Vim, 34 PSA) with ET were included in this non-randomised study. Evaluation using the Essential Tremor Rating Scale (ETRS) was performed before, and one year after surgery concerning PSA DBS, and at a mean of 28 ± 24 months concerning Vim DBS. Items 5/6 and 11-14 (hand tremor and hand function) were selected for analysis of tremor outcome. The efficacy of DBS on essential tremor was not related to age or gender. Nor was it associated with the severity of tremor when the percentual reduction of tremor on stimulation was taken into account. However, patients with a more severe tremor at baseline had a higher degree of residual tremor on stimulation. Tremor in the treated hand and hand function were improved with 70% in the Vim group and 89% in the PSA group.
  •  
4.
  • Blomstedt, Patric, et al. (författare)
  • The posterior subthalamic area in the treatment of movement disorders : past, present, and future
  • 2009
  • Ingår i: Neurosurgery. - 0148-396X .- 1524-4040. ; 64:6, s. 1029-1038
  • Tidskriftsartikel (refereegranskat)abstract
    • The introduction of thalamotomy in 1954 led naturally to exploration of the underlying subthalamic area, with the development of such procedures as campotomy and subthalamotomy in the posterior subthalamic area. The most popular of these procedures was the subthalamotomy, which was performed in thousands of patients for various movement disorders. Today, in the deep brain stimulation (DBS) era, subthalamic nucleus DBS is the treatment of choice for Parkinson's disease, whereas thalamic and pallidal DBS are mainly used for nonparkinsonian tremor and dystonia, respectively. The interest in DBS in the posterior subthalamic area has been quite limited, however, with a total of 95 patients presented in 14 articles. During recent years, interest has increased, and promising results have been published concerning both Parkinson's disease and nonparkinsonian tremor. We reviewed the literature to investigate the development of surgery in the posterior subthalamic area from the lesional era to the present.
  •  
5.
  • Blomstedt, Patric, et al. (författare)
  • Unilateral caudal zona incerta deep brain stimulation for Parkinsonian tremor
  • 2012
  • Ingår i: Parkinsonism & Related Disorders. - : Elsevier. - 1353-8020 .- 1873-5126. ; 18:10, s. 1062-1066
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The subthalamic nucleus is currently the target of choice in deep brain stimulation (DBS) for Parkinsons disease (PD), while thalamic DBS is used in some cases of tremor-dominant PD. Recently, a number of studies have presented promising results from DBS in the posterior subthalamic area, including the caudal zona incerta (cZi). The aim of the current study was to evaluate cZi DBS in tremor-dominant Parkinsons disease. less thanbrgreater than less thanbrgreater thanMethods: 14 patients with predominately unilateral tremor-dominant PD and insufficient relief from pharmacologic therapy were included and evaluated according to the motor part of the Unified Parkinson Disease Rating Scale (UPDRS). The mean age was 65 +/- 6.1 years and the disease duration 7 +/- 5.7 years. Thirteen patients were operated on with unilateral cZi DBS and 1 patient with a bilateral staged procedure. Five patients had non-L-dopa responsive symptoms. The patients were evaluated on/off medication before surgery and on/off medication and stimulation after a minimum of 12 months after surgery. less thanbrgreater than less thanbrgreater thanResults: At the follow-up after a mean of 18.1 months stimulation in the off-medication state improved the contralateral UPDRS III score by 47.7%. Contralateral tremor, rigidity, and bradykinesia were improved by 82.2%, 34.3%, and 26.7%, respectively. Stimulation alone abolished tremor at rest in 10 (66.7%) and action tremor in 8 (533%) of the patients. less thanbrgreater than less thanbrgreater thanConclusion: Unilateral cZi DBS seems to be safe and effective for patients with severe Parkinsonian tremor. The effects on rigidity and bradykinesia were, however, not as profound as in previous reports of DBS in this area.
  •  
6.
  • Blomstedt, Yulia, et al. (författare)
  • 10 years follow-up of deep brain stimulation in the caudal zona incerta/posterior subthalamic area for essential tremor
  • 2023
  • Ingår i: Movement Disorders Clinical Practice. - : John Wiley & Sons. - 2330-1619. ; 10:5, s. 783-793
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Long-term data on the effects of deep brain stimulation (DBS) for essential tremor (ET) is scarce, especially regarding DBS in the caudal Zona incerta (cZi) and the posterior subthalamic area (PSA). Objectives: The aim of this prospective study was to evaluate the effect of cZi/PSA DBS in ET at 10 years after surgery.Methods: Thirty-four patients were included. All patients received cZi/PSA DBS (5 bilateral/29 unilateral) and were evaluated at regular intervals using the essential tremor rating scale (ETRS).Results: One year after surgery, there was a 66.4% improvement of total ETRS and 70.7% improvement of tremor (items 1–9) compared with the preoperative baseline. Ten years after surgery, 14 patients had died and 3 were lost to follow-up. In the remaining 17 patients, a significant improvement was maintained (50.8% for total ETRS and 55.8% for tremor items). On the treated side the scores of hand function (items 11–14) had improved by 82.6% at 1 year after surgery, and by 66.1% after 10 years. Since off-stimulation scores did not differ between year 1 and 10, this 20% deterioration of on-DBS scores was interpreted as a habituation. There was no significant increase in stimulation parameters beyond the first year.Conclusions: This 10 year follow up study, found cZi/PSA DBS for ET to be a safe procedure with a mostly retained effect on tremor, compared to 1 year after surgery, and in the absence of increase in stimulation parameters. The modest deterioration of effect of DBS on tremor was interpreted as habituation.
  •  
7.
  • Chen, Long Long, et al. (författare)
  • Genomics of severe and treatment-resistant obsessive–compulsive disorder treated with deep brain stimulation : a preliminary investigation
  • 2024
  • Ingår i: American Journal of Medical Genetics Part B. - : John Wiley & Sons. - 1552-4841 .- 1552-485X.
  • Tidskriftsartikel (refereegranskat)abstract
    • Individuals with severe and treatment-resistant obsessive-compulsive disorder (trOCD) represent a small but severely disabled group of patients. Since trOCD cases eligible for deep brain stimulation (DBS) probably comprise the most severe end of the OCD spectrum, we hypothesize that they may be more likely to have a strong genetic contribution to their disorder. Therefore, while the worldwide population of DBS-treated cases may be small (~300), screening these individuals with modern genomic methods may accelerate gene discovery in OCD. As such, we have begun to collect DNA from trOCD cases who qualify for DBS, and here we report results from whole exome sequencing and microarray genotyping of our first five cases. All participants had previously received DBS in the bed nucleus of stria terminalis (BNST), with two patients responding to the surgery and one showing a partial response. Our analyses focused on gene-disruptive rare variants (GDRVs; rare, predicted-deleterious single-nucleotide variants or copy number variants overlapping protein-coding genes). Three of the five cases carried a GDRV, including a missense variant in the ion transporter domain of KCNB1, a deletion at 15q11.2, and a duplication at 15q26.1. The KCNB1 variant (hg19 chr20-47991077-C-T, NM_004975.3:c.1020G>A, p.Met340Ile) causes substitution of methionine for isoleucine in the trans-membrane region of neuronal potassium voltage-gated ion channel KV2.1. This KCNB1 substitution (Met340Ile) is located in a highly constrained region of the protein where other rare missense variants have previously been associated with neurodevelopmental disorders. The patient carrying the Met340Ile variant responded to DBS, which suggests that genetic factors could potentially be predictors of treatment response in DBS for OCD. In sum, we have established a protocol for recruiting and genomically characterizing trOCD cases. Preliminary results suggest that this will be an informative strategy for finding risk genes in OCD.
  •  
8.
  • Fytagoridis, Anders, et al. (författare)
  • Complications and side effects of deep brain stimulation in the posterior subthalamic area.
  • 2010
  • Ingår i: Stereotactic and Functional Neurosurgery. - : Karger. - 1011-6125 .- 1423-0372. ; 88:2, s. 88-93
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The posterior subthalamic area (PSA), including the zona incerta and prelemniscal radiation (Raprl), has recently been presented in number of publications as a promising target for deep brain stimulation (DBS) in the treatment of various movement disorders. In order to evaluate the safety of the procedure, we analyzed our initial 40 patients for complications and side effects. METHODS: 40 patients treated with PSA DBS for Parkinson's disease, essential tremor and other forms of tremor were included. RESULTS: The most severe complication was 1 transient mild hemiparesis and 1 infection. Minor complications and side effects were relatively frequent, including mild transient dysphasia in 22.5% of the patients. CONCLUSIONS: Few serious complications were encountered, and we consider the PSA to be a safe target for DBS.
  •  
9.
  • Fytagoridis, Anders, et al. (författare)
  • Deep Brain Stimulation of the Caudal Zona Incerta : Tremor Control in Relation to the Location of Stimulation Fields
  • 2016
  • Ingår i: Stereotactic and Functional Neurosurgery. - : S. Karger. - 1011-6125 .- 1423-0372. ; 94:6, s. 363-370
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The caudal zona incerta (cZi) and posterior subthalamic area (PSA) are an emerging deep brain stimulation (DBS) target for essential tremor (ET). Objectives: To evaluate the efficacy of tremor control in relation to the anatomical locations of stimulation fields in 50 patients with ET and DBS of the cZi. Methods: A total of 240 contacts were evaluated separately with monopolar stimulation, and amplitudes were optimized for improvement of tremor and hand function. Stimulation fields, i.e., volumes of neural activation, were simulated for each optimized setting and assembled into probabilistic stimulation maps (PSMs). Results: There were differences in the anatomical distribution of PSMs associated with good versus poor tremor control. The location of PSMs which achieved good and excellent tremor control corresponded well with the PSM for the clinically used settings, and they were located within the superior part of the PSA. Conclusions: PSMs may serve as a useful tool for defining the most efficacious anatomical location of stimulation. The best tremor control in this series of cZi DBS was achieved with stimulation of the superior part of the PSA, which corresponds to the final part of the cerebellothalamic projections before they reach the ventral lateral thalamus.
  •  
10.
  • Fytagoridis, Anders (författare)
  • Deep brain stimulation of the posterior subthalamic area in the treatment of movement disorders
  • 2012
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Background: The posterior subthalamic area (PSA) is essentially composed of the caudal Zona incerta and the prelemniscal radiation. Subthalamotomy in the PSA was renowned for its effectiveness in alleviating movement disorders and particularly tremor. The modern literature on DBS of this area is limited, but promising results have been presented for Parkinson’s disease (PD), essential tremor (ET) and other movement disorders.   Aim: To evaluate the safety of PSA DBS with emphasis on the panorama of side effects, the distribution of stimulation-induced side effects and the effects of PSA DBS on verbal fluency. To evaluate the therapeutic effect of PSA DBS on less common forms of tremor, tremor-dominant PD, and concerning the long-term results in ET. Method: 40 patients were evaluated regarding side effects of the procedure. 28 patients with ET were analyzed for stimulation-induced side effects in a standardized manner. The locations of the contacts that caused stimulation-induced side effects were plotted on atlas slides. A 3-D model of the area was created based on these slides. Verbal fluency was analyzed in 17 patients with ET before surgery, after 3 days and finally after 1 year. Five patients with less common forms of tremor and 18 with ET were evaluated according to the ETRS at baseline and one year or 3-5 years after surgery, respectively. 14 patients with mainly unilateral tremor-dominant PD were evaluated a mean of 18 months after surgery according to the motor part of UPDRS. Results: PSA DBS was associated with few serious side-effects, but a transient and mild postoperative dysphasia was found in 22.5% of the patients. There was a slight transient decline in the performance on verbal fluency tests immediately after surgery. Visualization of the contacts causing stimulation-induced side effects showed that identical responses can be elicited from various points in the PSA and its vicinity. The effect on the less common forms of tremor was excellent except for neuropathic tremor where the effect was moderate. A pronounced and sustained microlesional effect was seen for some of the patients. After a mean of 4 years with unilateral PSA DBS the total ETRS score was improved by 52.4%, tremor by 91.8% and hand function by 78.0% in the patients with ET. There was no increase in the stimulation strength over time. In PD, the scores improved 47.7% for contralateral UPDRS III. Contralateral tremor, rigidity, and bradykinesia improved by 82.2%, 34.3%, and 26.7%, respectively. Conclusions: PSA DBS generally seem to be a safe procedure, but it may be associated with transient declines of verbal fluency. There was no clear somatotopic pattern with regard to stimulation-induced side effects in the PSA. PSA DBS can alleviate tremor regardless of the etiology. The long-term effects in ET were favorable when compared to our previous results of Vim DBS. The effect on Parkinsonian tremor was satisfying, however, the reductions of rigidity and bradykinesia were less compared to previous studies of PSA DBS for PD.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 23
Typ av publikation
tidskriftsartikel (19)
doktorsavhandling (2)
annan publikation (1)
forskningsöversikt (1)
Typ av innehåll
refereegranskat (20)
övrigt vetenskapligt/konstnärligt (3)
Författare/redaktör
Fytagoridis, Anders (23)
Blomstedt, Patric (20)
Hariz, Marwan (6)
Åström, Mattias (6)
Stenmark Persson, Ra ... (3)
Forsgren, Lars (2)
visa fler...
Hariz, Gun-Marie (2)
Naesström, Matilda (2)
Sandvik, Ulrika, 197 ... (2)
Blomstedt, Yulia (2)
Johansson, Anders (1)
Matthews, Keith (1)
Nyberg, Lars (1)
Agren, Richard (1)
Bartek, Jiri, Jr. (1)
Zrinzo, Ludvic (1)
Wårdell, Karin, 1959 ... (1)
Linder, Jan (1)
Bergenheim, Tommy (1)
Zsigmond, Peter (1)
Wårdell, Karin (1)
Vogel, Dorian (1)
Hemm-Ode, Simone (1)
Johansson, Johannes (1)
Zsigmond, Peter, 196 ... (1)
Rück, Christian (1)
Mataix-Cols, David (1)
Crowley, James J. (1)
Carstam, Louise (1)
Sandvik, Ulrika (1)
Tisch, S (1)
Blomstedt, Patric, P ... (1)
Awad, Amar (1)
Awad, Amar, 1988- (1)
Koskinen, Lars-Owe (1)
Samuelsson, Jörgen (1)
Tisch, Stephen (1)
Fredricks, Anna (1)
Taira, Takaomi (1)
Philipson, Johanna, ... (1)
Krauss, Joachim K. (1)
Halvorsen, Matthew (1)
Jalakas, Mattis (1)
Ågren, Richard (1)
Doshi, Paresh (1)
Fins, Joseph J. (1)
Hamani, Clement (1)
Nuttin, Bart (1)
Wu, Hemmings (1)
Chen, Long Long (1)
visa färre...
Lärosäte
Umeå universitet (22)
Linköpings universitet (9)
Karolinska Institutet (9)
Uppsala universitet (2)
Språk
Engelska (23)
Forskningsämne (UKÄ/SCB)
Medicin och hälsovetenskap (23)
Teknik (2)

År

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy