Gamma Knife thalamotomy for essential tremor

2008 ◽  
Vol 108 (1) ◽  
pp. 111-117 ◽  
Author(s):  
Douglas Kondziolka ◽  
Joseph G. Ong ◽  
John Y. K. Lee ◽  
Robert Y. Moore ◽  
John C. Flickinger ◽  
...  
Keyword(s):  
Essential Tremor ◽  
Gamma Knife ◽  
Rating Scale ◽  
Surgical Techniques ◽  
Speech Impairment ◽  
Action Tremor ◽  
Before And After ◽  
The Mean ◽  
Writing Scores

Object The purpose of this study was to evaluate the results following Gamma Knife thalamotomy (GKT) for medically refractory essential tremor in a series of patients in whom open surgical techniques were not desirable. Methods Thirty-one patients underwent GKT for disabling essential tremor after medical therapy had failed. Their mean age was 77 years. Most patients were elderly or had concomitant medical illnesses. A single 4-mm isocenter was used to target a maximum dose of 130 or 140 Gy to the nucleus ventralis intermedius. Items from the Fahn-Tolosa-Marin clinical tremor rating scale were used to grade tremor and handwriting before and after radiosurgery. Results The median follow-up was 36 months. In the group of 26 evaluable patients, the mean tremor score (± standard deviation) was 3.7 ± 0.1 preoperatively and 1.7 ± 0.3 after radiosurgery (p < 0.000015). The mean handwriting score was 2.8 ± 0.2 before GKT and 1.7 ± 0.2 afterward (p < 0.0002). After radiosurgery, 18 patients (69%) showed improvement in both action tremor and writing scores, 6 (23%) only in action tremor scores, and 3 (12%) in neither tremor nor writing. Permanent mild right hemiparesis and speech impairment developed in 1 patient 6 months after radiosurgery. Another patient had transient mild right hemiparesis and dysphagia. Conclusions Gamma Knife thalamotomy is a safe and effective therapy for medically refractory essential tremor. Its use is especially valuable for patients ineligible for radiofrequency thalamotomy or deep brain stimulation. Patients must be counseled on potential complications, including the low probability of a delayed neurological deficit.

Gamma Knife Thalamotomy for Parkinson Disease and Essential Tremor: A Prospective Multicenter Study

Neurosurgery ◽  
2011 ◽  
Vol 70 (3) ◽  
pp. 526-536 ◽  
Author(s):  
Chihiro Ohye ◽  
Yoshinori Higuchi ◽  
Toru Shibazaki ◽  
Takao Hashimoto ◽  
Toru Koyama ◽  
...  
Keyword(s):  
Parkinson Disease ◽  
Essential Tremor ◽  
Gamma Knife ◽  
Rating Scale ◽  
Spherical Shape ◽  
High Signal ◽  
Lateral Part ◽  
Thalamic Lesion ◽  
Clinical Effects

Abstract BACKGROUND: No prospective study of gamma knife thalamotomy for intractable tremor has previously been reported. Objective: To clarify the safety and optimally effective conditions for performing unilateral gamma knife (GK) thalamotomy for tremors of Parkinson disease (PD) and essential tremor (ET), a systematic postirradiation 24-month follow-up study was conducted at 6 institutions. We present the results of this multicenter collaborative trial. Methods: In total, 72 patients (PD characterized by tremor, n = 59; ET, n = 13) were registered at 6 Japanese institutions. Following our selective thalamotomy procedure, the lateral part of the ventralis intermedius nucleus, 45% of the thalamic length from the anterior tip, was selected as the GK isocenter. A single 130-Gy shot was applied using a 4-mm collimator. Evaluation included neurological examination, magnetic resonance imaging and/or computerized tomography, the unified Parkinson's disease rating scale (UPDRS), electromyography, medication change, and video observations. Results: Final clinical effects were favorable. Of 53 patients who completed 24 months of follow-up, 43 were evaluated as having excellent or good results (81.1%). UPDRS scores showed tremor improvement (parts II and III). Thalamic lesion size fluctuated but converged to either an almost spherical shape (65.6%), a sphere with streaking (23.4%), or an extended high-signal zone (10.9%). No permanent clinical complications were observed. Conclusion: GK thalamotomy is an alternative treatment for intractable tremors of PD as well as for ET. Less invasive intervention may be beneficial to patients.

Gamma Knife thalamotomy for treatment of essential tremor: long-term results

2010 ◽  
Vol 112 (6) ◽  
pp. 1311-1317 ◽  
Author(s):  
Ronald F. Young ◽  
Francisco Li ◽  
Sandra Vermeulen ◽  
Robert Meier
Keyword(s):  
Surgical Treatment ◽  
Essential Tremor ◽  
Gamma Knife ◽  
Surgical Intervention ◽  
Long Term Results ◽  
The Mean ◽  
Lost To Follow Up ◽  
Deep Brain

Object The goal of this report was to describe the safety and effectiveness of nucleus ventralis intermedius (VIM) thalamotomy performed with the Leksell Gamma Knife (GK) for the treatment of essential tremor (ET). Methods One hundred seventy-two patients underwent a total of 214 VIM thalamotomy procedures with the Leksell GK between February 1994 and March 2007 for treatment of disabling ET. Eleven patients were lost to follow-up less than 1 year after the procedures, so that in this report the authors describe the results in 161 patients who underwent a total of 203 thalamotomies (119 unilateral and 42 bilateral). Results There were statistically significant decreases (p < 0.0001) in tremor scores for both writing and drawing. The mean postoperative follow-up duration for all patients was 44 ± 33 months. Fifty-four patients have been followed for more than 60 months posttreatment. There were 14 patients who suffered neurological side effects that were temporary (6) or permanent (8), which accounted for 6.9% of the 203 treatments. All complications were related to lesions that grew larger than expected. Conclusions A VIM thalamotomy with the Leksell GK offers a safe and effective alternative for surgical treatment of ET. It is particularly applicable to patients who are not ideal candidates for deep brain stimulation but can be offered to all patients who are considering surgical intervention for ET.

scholarly journals Two year data from a preliminary study of double lesion site MRgFUS treatment of Essential Tremor targeting the thalamus and the posterior subthalamic area

2021 ◽  
Author(s):  
Ayesha Jameel ◽  
Wladyslaw Gedroyc ◽  
Dipankar Nandi ◽  
Bryn Jones ◽  
Olga Kirmi ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Essential Tremor ◽  
Focused Ultrasound ◽  
Rating Scale ◽  
Severity Scores ◽  
The Mean ◽  
Preliminary Study ◽  
Clinical Rating Scale

AbstractBackgroundMR-guided focused ultrasound (MRgFUS) is an effective treatment for essential tremor (ET). However, the optimal intracranial target sites remain to be determined.ObjectiveTo assess MRgFUS induced sequential lesions in (anterior-VIM/VOP nuclei) the thalamus and then posterior subthalamic area (PSA) performed during the same procedure for alleviating ET.Methods14 patients had unilateral MRgFUS lesions placed in anterior-VIM/VOP then PSA. Bain-Findley Spirals were collected during MRgFUS from the treated arm (BFS-TA) and throughout the study from the treated (BFS-TA) and non-treated (BFS-NTA) arms and scored by blinded assessors. Although, the primary outcome was change in the BFS-TA from baseline to 12 months we have highlighted the 24 month data.Secondary outcomes included the Clinical Rating Scale for Tremor (CRST), Quality of Life for ET (QUEST) and PHQ-9 depression scores.ResultsThe mean improvement in the BFS-TA from baseline to 24 months was 41.1% (p<0.001) whilst BFS-NTA worsened by 8.8% (p<0.001). Intra-operative BFS scores from the targeted arm showed a mean 27.9% (p<0.001) decrease after anterior-VIM/VOP ablation and an additional 30.1% (p<0.001) reduction from post anterior-VIM/VOP to post-PSA ablation.Mean improvements at 24 month follow-up in the CRST-parts A, B and C were 60.7%, 30.4% and 65.6% respectively and 37.8% in QUEST-tremor score (all p<0.05). Unilateral tremor severity scores decreased in the treated arm (UETTS-TA) 72.9% (p=0.001) and non-treated arm (UETTS-NTA) 30.5% (p=0.003). At 24 months residual adverse effects were slight unsteadiness (n=1) and mild hemi-chorea (n=1).ConclusionUnilateral anterior-VIM/VOP and PSA MRgFUS significantly diminished contralateral arm tremor with improvements in arm function, tremor related disability and quality of life, with an acceptable adverse event profile.

Gamma knife thalamotomy for treatment of tremor: long-term results

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 128-135 ◽  
Author(s):  
Ronald F. Young ◽  
Skip Jacques ◽  
Rufus Mark ◽  
Oleg Kopyov ◽  
Brian Copcutt ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Essential Tremor ◽  
Gamma Knife ◽  
Rating Scale ◽  
Long Term Results ◽  
Content Type ◽  
Fine Print

Object. The purpose of this study was to investigate the long-term effects of gamma knife thalamotomy for treatment of disabling tremor. Methods. One hundred fifty-eight patients underwent magnetic resonance imaging—guided radiosurgical nucleus ventralis intermedius (VIM) thalamotomy for the treatment of parkinsonian tremor (102 patients), essential tremor (52 patients), or tremor due to stroke, encephalitis, or cerebral trauma (four patients). Preoperative and postoperative blinded assessments were performed by a team of independent examiners skilled in the evolution of movement disorders. A single isocenter exposure with the 4-mm collimator helmet of the Leksell gamma knife unit was used to make the lesions. In patients with Parkinson's disease 88.3% became fully or nearly tremor free, with a mean follow up of 52.5 months. Statistically significant improvements were seen in Unified Parkinson's Disease Rating Scale tremor scores and rigidity scores, and these improvements were maintained in 74 patients followed 4 years or longer. In patients with essential tremor, 92.1% were fully or nearly tremor free postoperatively, but only 88.2% remained tremor free by 4 years or more post-GKS. Statistically significant improvements were seen in the Clinical Rating Scale for tremor in essential tremor patients and these improvements were well maintained in the 17 patients, followed 4 years or longer. Only 50% of patients with tremor of other origins improved significantly. One patient sustained a transient complication and two patients sustained mild permanent side effects from the treatments. Conclusions. Gamma knife VIM thalamotomy provides relief from tremor equivalent to that provided by radiofrequency thalamotomy or deep brain stimulation, but it is safer than either of these alternatives. Long-term follow up indicates that relief of tremor is well maintained. No long-term radiation-induced complications have been observed.

scholarly journals Focused Ultrasound Thalamotomy for the Treatment of Essential Tremor: A 2-Year Outcome Study of Chinese People

2021 ◽  
Vol 13 ◽  
Author(s):  
Peihan Wu ◽  
Wei Lin ◽  
Kun Hong Li ◽  
Hui-Chin Lai ◽  
Ming-Tsung Lee ◽  
...  
Keyword(s):  
Essential Tremor ◽  
Focused Ultrasound ◽  
Rating Scale ◽  
Density Ratio ◽  
Extended Period ◽  
Maximum Energy ◽  
Chinese Patients ◽  
Average Maximum ◽  
The Mean

Background: Essential tremor (ET) is a common movement disorder among elderly individuals worldwide and is occasionally associated with a high risk for mild cognitive impairment and dementia. This retrospective study aimed to determine the clinical outcome of unilateral magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy in Chinese patients with ET.Methods: In total, 31 male and 17 female patients with drug-refractory ET were enrolled in this research study from January 2017 to September 2019. The severity of tremor and disability were assessed using the Clinical Rating Scale for Tremor (CRST) within a 2-year follow-up period.Results: The mean age of the participants was 59.14 ± 13.5 years. The mean skull density ratio (SDR) was 0.5 ± 0.1. The mean highest temperature was 57.0 ± 2.4°C. The mean number of sonications was 10.0 ± 2.6. The average maximum energy was 19,710.5 ± 8,624.9 J. The total CRST scores and sub-scores after MRgFUS thalamotomy significantly reduced during each follow-up (p &lt; 0.001). All but four (8.3%) of the patients had reversible adverse events (AEs) after the procedure.Conclusions: MRgFUS had sustained clinical efficacy 2 years after treatment for intractable ET. Only few patients presented with thalamotomy-related AEs including numbness, weakness, and ataxia for an extended period. Most Chinese patients were treated safely and effectively despite their low SDR.

Stimulation of the subthalamic region for essential tremor

2004 ◽  
Vol 101 (1) ◽  
pp. 48-54 ◽  
Author(s):  
Puneet Plaha ◽  
Nikunj K. Patel ◽  
Steven S. Gill
Keyword(s):  
Essential Tremor ◽  
Upper Limb ◽  
Functional Disability ◽  
Rating Scale ◽  
Related Complication ◽  
Content Type ◽  
The Mean ◽  
Fine Print ◽  
Deep Brain

Object. The goal of this study was to determine the safety and efficacy of bilateral subthalamic region stimulation in the treatment of essential tremor (ET). Methods. Following induction of general anesthesia, four patients with disabling tremor that had proved to be refractory to pharmacotherapy underwent magnetic resonance imaging—guided deep brain stimulation (DBS) of the bilateral subthalamic region. Tremor was assessed by applying the Fahn-Tolosa-Marín Tremor Rating Scale at baseline and again at the 12-month follow-up examination. Following surgery the total tremor score improved by 80.1% (from a baseline mean score of 63 ± 15.1 to a score of 11.8 ± 3.9 at 12 months postoperatively). There was a significant improvement (p < 0.0001) in the mean tremor score of the upper limb (postural and action component) from a baseline score of 3 ± 0.9 to a score of 0.5 ± 0.5 at 12 months postoperatively. In two patients with Score 4 head tremor complete arrest of the tremor was observed at 12 months. Motor function scores of the upper limb for drawing spirals, pouring water, and drawing lines improved significantly (p < 0.05) by 66.7, 76.9, and 58.3%, respectively. Handwriting improved by 68%, but this gain was not significant. The mean activities of daily living score at baseline was 20 ± 3.2; there was an 88.8% improvement in this score to 2.3 ± 1.5 at the 12-month evaluation. The voltage required for effective tremor control was low (mean 1.8 ± 0.2 V) and, along with the other parameters of DBS (frequency and pulse width), did not change significantly over the 12-month period. Tolerance to the action component of tremor was not seen. There was no procedural or stimulation-related complication. Conclusions. Bilateral subthalamic region stimulation is effective in arresting tremor and head titubation, as well as functional disability in ET. Complications like dysarthria and disequilibrium were not seen. These patients required low voltages of stimulation and did not develop a tolerance to the treatment.

Radiosurgery for dural carotid-cavernous sinus fistulas: Gamma Knife compared with XKnife radiosurgery

2010 ◽  
Vol 113 (Special_Supplement) ◽  
pp. 9-20 ◽  
Author(s):  
Hung-Chuan Pan ◽  
Ming-Hsi Sun ◽  
Jason Sheehan ◽  
Meei-Ling Sheu ◽  
Clayton Chi-Chang Chen ◽  
...  
Keyword(s):  
Clinical Improvement ◽  
Gamma Knife ◽  
Temporal Lobe ◽  
Treatment Modalities ◽  
Conformity Index ◽  
Index Number ◽  
The Mean ◽  
Instrument Accuracy ◽  
Group 1

Object In the modern era, stereotactic radiosurgery is an important part of the multidisciplinary and multimodality approach used to treat dural carotid-cavernous fistulas (DCCFs). Based on the ease of performance of techniques to fuse cerebral angiography studies with MR images or CT scans during the radiosurgical procedure, the Gamma Knife and XKnife are 2 of the most popular radiosurgical instruments for patients with DCCF. In this study, the authors compared the efficacy, neurological results, and complications associated with these 2 radiosurgical devices when used for DCCF. Methods Records for 41 patients with DCCF (15 treated using the XKnife and 26 with Gamma Knife surgery [GKS]) were retrieved from a radiosurgical database encompassing the period of September 2000 to August 2008. Among these patients, at least 2 consecutive MR imaging or MR angiography studies obtained after radiosurgery were available for determining radiological outcome of the fistula. All patients received regular follow-up to evaluate the neurological and ophthalmological function at an interval of 1–3 months. The symptomatology, obliteration rate, radiation dose, instrument accuracy, and adverse effects were determined for each group and compared between 2 groups. The data were analyzed using the Student t-test. Results The mean age of the patients was 63 ± 2.6 years, and the mean follow-up period was 63.1 ± 4.4 months (mean ± SD). Thirty-seven patients (90%) achieved an obliteration of the DCCF (93% in the XKnife cohort and 88% for the GKS cohort). In 34 of 40 patients (85%) with chemosis and proptosis of the eyes, these symptoms were resolved after treatment (4 had residual fistula and 2 had arterializations of sclera). All 5 patients with high intraocular pressure demonstrated clinical improvement. Ten (71%) of 14 patients with cranial nerve palsy demonstrated improvement following radiosurgery. Significant discrepancies of treatment modalities existed between the XKnife and GKS groups, such as radiation volume, conformity index, number of isocenters, instrument accuracy, peripheral isodose line, and maximum dosage. The XKnife delivered significantly higher radiation dosage to the lens, optic nerve, optic chiasm, bilateral temporal lobe, and brainstem. Few adverse events occurred, but included 1 patient with optic neuritis (GKS group), 1 intracranial hemorrhage (XKnife group), 1 brainstem edema (XKnife), and 3 temporal lobe radiation edemas (XKnife). Conclusions Radiosurgery affords a substantial chance of radiological and clinical improvement in patients with DCCFs. The Gamma Knife and XKnife demonstrated similar efficacy in the obliteration of DCCFs. However, a slightly higher incidence of complications occurred in the XKnife group.

scholarly journals Unilateral lateral rectus recession is an effective surgery for intermittent exotropia in young children

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Oriel Spierer ◽  
Abraham Spierer
Keyword(s):  
Young Children ◽  
Success Rate ◽  
Lateral Rectus ◽  
Intermittent Exotropia ◽  
Age At Surgery ◽  
Surgical Methods ◽  
Before And After ◽  
The Mean ◽  
Consecutive Esotropia

Abstract Background Different surgical methods have been suggested for the correction of intermittent exotropia. Unilateral lateral rectus recession has been described as a surgical alternative for small and moderate-angle exotropia. In general, previous studies did not focus on the outcomes of unilateral lateral rectus recession in young children with intermittent exotropia. The purpose of this study is to evaluate the surgical outcomes of unilateral lateral rectus recession in the treatment of moderate-angle exotropia (≤ 25 PD (prism diopters)) in children. Methods The charts of all patients younger than 12 years of age with moderate-angle exotropia (up to 25 PD) who were operated during the years 2006–2018 were retrospectively reviewed. Fifty-eight patients underwent unilateral lateral rectus recession and had a minimum follow up of 6 months. The angle of exotropia (PD) before and after surgery and the success rate were documented. Results Mean age at surgery was 6.4 ± 1.9 (range 3.5–11.0) years. Exotropia improved from a preoperative angle of 21.4 ± 4.0 PD to 3.5 ± 5.9 PD postoperatively (p < 0.001). Success rate, defined as deviation of ≤ 10 PD, was achieved in 86.2%. There were 2 (3.4%) cases of overcorrection (consecutive esotropia). There were no intra- or postoperative complications. The mean follow-up duration after surgery was 2.3 ± 1.7 years. Conclusions In children with moderate angle exotropia, good postoperative success rate was achieved by performing unilateral lateral rectus recession.

Gamma knife radiosurgery as a lesioning technique in movement disorder surgery

1997 ◽  
Vol 2 (3) ◽  
pp. E13 ◽  
Author(s):  
Ronald F. Young ◽  
Anne Shumway-Cook ◽  
Sandra S. Vermeulen ◽  
Peter Grimm ◽  
John Blasko ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Movement Disorder ◽  
Gamma Knife ◽  
Movement Disorders ◽  
Rating Scale ◽  
Gamma Knife Radiosurgery ◽  
Magnetic Resonance Images ◽  
Maximum Deviation

Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. They were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson's disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with dose maximums from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson's Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Eighty-five and seven-tenths percent of patients undergoing pallidotomy who had exhibited levodopa-induced dyskinesias had total or near-total relief of that symptom. Clinical assessment indicated improvement of bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Ipsilateral total UPDRS and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular interals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

scholarly journals Selective Arterial Embolization of Renal Angiomyolipomas with a N-Butyl Cyanoacrylate-Lipiodol Mixture: Efficacy, Safety, Short- and Mid-Term Outcomes

2021 ◽  
Vol 10 (18) ◽  
pp. 4062
Author(s):  
François-Victor Prigent ◽  
Kévin Guillen ◽  
Pierre-Olivier Comby ◽  
Julie Pellegrinelli ◽  
Nicolas Falvo ◽  
...  
Keyword(s):  
Arterial Embolization ◽  
Volume Reduction ◽  
Renal Angiomyolipoma ◽  
Cyanoacrylate Glue ◽  
Selective Arterial Embolization ◽  
Before And After ◽  
The Mean ◽  
Magnetic Resonance Imaging Mri ◽  
Postembolization Syndrome

Selective arterial embolization (SAE) for renal angiomyolipoma (rAML) is effective to treat or prevent bleeding. We report our experience using a cyanoacrylate–Lipiodol mixture. We performed a single-center retrospective review of all rAMLs embolized with cyanoacrylate glue between July 2014 and June 2020. Demographics, tuberous sclerosis complex (TSC) status, clinical presentation, angiography features, and follow-up data were recorded. Pre- and post-procedure rAML sizes and volumes were estimated from computed tomography (CT) or magnetic resonance imaging (MRI) studies. Kidney function was assessed before and after the procedure. We identified 24 patients (22 females and 2 males, mean age 51 years) treated for 27 AMLs, either prophylactically (n = 20) or as an emergency (n = 4). Technical success was achieved for 25/27 AMLs; two patients, each with a single AML, required nephrectomy and repeated embolization, respectively. Major complications occurred in three patients and minor complications such as postembolization syndrome in 15 patients. AML volume reduction after embolization was 55.1% after a mean follow-up of 15 months (range, 1–72 months). Factors associated with greater volume reduction were a smaller percentage of fat (p = 0.001), larger initial rAML volume (p = 0.014), and longer follow-up (p = 0.0001). The mean creatinine level did not change after SAE. Embolization of rAMLs with a mixture of cyanoacrylate and Lipiodol is feasible, safe, and effective in significantly decreasing tumor volume.

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