Pattern of pressure gradient alterations after venous sinus stenting for idiopathic intracranial hypertension predicts stent-adjacent stenosis: a proposed classification system

2017 ◽  
Vol 10 (4) ◽  
pp. 391-395 ◽  
Author(s):  
Daniel Raper ◽  
Thomas J Buell ◽  
Dale Ding ◽  
Ching-Jen Chen ◽  
Robert M Starke ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Patient Characteristics ◽  
Transverse Sinus ◽  
Venous Sinus ◽  
Type I ◽  
Type Ii ◽  
Type Iii

ObjectiveVenous sinus stenting (VSS) is a safe and effective treatment for idiopathic intracranial hypertension (IIH) with angiographic venous sinus stenosis. However, predictors of stent-adjacent stenosis (SAS) remain poorly defined.MethodsWe performed a retrospective review of 47 patients with IIH and intracranial venous stenosis who underwent VSS with pre- and post-stent venography. Patient characteristics, treatments and outcomes were reviewed. Changes in pressure gradient after VSS were classified according to pattern of gradient resolution into types I–III.ResultsType I gradient resolution, in which mean venous pressure (MVP) in the transverse sinus (TS) decreases towards MVP in the sigmoid sinus (SS), occurred in 18 patients (38.3%). Type II gradient resolution pattern, in which SS MVP increases towards that in the TS, occurred in 7patients (14.9%). Type III pattern, in which MVP equilibrates to a middle value, occurred in 22patients (46.8%). SAS occurred in 0%, 28.6%, and 22.7% of patients in types I, II and III, respectively. Compared with patients with type I gradient resolution, SAS was more common in those with type II (p=0.0181) and type III (p=0.0306) patterns.ConclusionsThe pattern of change in the trans-stenosis venous pressure gradient may be predictive of SAS and is a useful tool for classifying the response of the venous obstruction to stenting. A type I pattern appears to represent the ideal response to VSS. Some patients with type II and III changes, particularly if they have other predictors of recurrent stenosis, may benefit from longer initial stent constructs.

Abstract 1122‐000232: The Importance of Performing Venous Pressure Measurements Following Venous Sinus Stenting for Idiopathic Intracranial Hypertension

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Yazan Radaideh
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Stent Placement ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Sigmoid Sinus ◽  
Venous Sinus ◽  
Pressure Measurements ◽  
Sinus Stenosis ◽  
The Right

Introduction : Although venous sinus stenting is an established treatment for medically refractory idiopathic intracranial hypertension, a subset of patients shows little or no improvement of symptoms after stenting. While this could be related to a number of factors, failure to sufficiently address the pressure gradient is one that can be recognized during the treatment procedure. We describe two patients who had a persistent venous pressure gradient after stent placement. Once identified, a second stent was placed with subsequent resolution of the pressure gradient. Methods : This retrospective chart review identified patients at a single institution who underwent venous sinus stenting and required immediate placement of a second venous sinus stent for a persistent pressure gradient. Results : Two patients with refractory idiopathic intracranial hypertension underwent cerebral angiography with venous manometry. In the first patient, unilateral venous sinus stenosis was present with a maximum pressure of 50 mmHg, which only decreased to 30 mmHg after placement of a right transverse‐sigmoid sinus stent. Subsequent manometry revealed a persistent gradient between the superior sagittal sinus and the right transverse sinus, which resolved after placement of a second stent in this location. In the second patient, bilateral stenosis was observed at the transverse‐sigmoid sinus junction; the maximum venous pressure was 40 mmHg, and a gradient of 30 mmHg was measured at the right transverse‐sigmoid junction, where a venous sinus stent was placed. Venous sinus pressure measurements performed immediately after the stent placement demonstrated a persistent pressure gradient of 20 mmHg in the contralateral transverse‐sigmoid sinus junction, which resolved after contralateral stent placement. Both patients showed sustained improvement in their symptoms at 1 year follow up. Conclusions : In some patients with idiopathic intracranial hypertension and venous sinus stenosis, a single stent may not sufficiently reduce the pressure gradient. A second stent may be required; however, this is only detectable with post‐stent pressure measurements. Performing manometry after stent placement should be routinely performed in order to detect persistent venous pressure gradient.

scholarly journals Incidence and predictors of dural venous sinus pressure gradient in idiopathic intracranial hypertension and non-idiopathic intracranial hypertension headache patients: results from 164 cerebral venograms

2017 ◽  
Vol 126 (2) ◽  
pp. 347-353 ◽  
Author(s):  
Michael R. Levitt ◽  
Randall J. Hlubek ◽  
Karam Moon ◽  
M. Yashar S. Kalani ◽  
Peter Nakaji ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Venous Sinus ◽  
Patient Demographics ◽  
Procedural Complications ◽  
Dural Venous Sinus ◽  
Cerebral Venous Pressure ◽  
Headache Patients

OBJECTIVE Cerebral venous pressure gradient (CVPG) from dural venous sinus stenosis is implicated in headache syndromes such as idiopathic intracranial hypertension (IIH). The incidence of CVPG in headache patients has not been reported. METHODS The authors reviewed all cerebral venograms with manometry performed for headache between January 2008 and May 2015. Patient demographics, headache etiology, intracranial pressure (ICP) measurements, and radiographic and manometric results were recorded. CVPG was defined as a difference ≥ 8 mm Hg by venographic manometry. RESULTS One hundred sixty-four venograms were performed in 155 patients. There were no procedural complications. Ninety-six procedures (58.5%) were for patients with IIH. The overall incidence of CVPG was 25.6% (42 of 164 procedures): 35.4% (34 of 96 procedures) in IIH patients and 11.8% (8 of 68 procedures) in non-IIH patients. Sixty procedures (36.6%) were performed in patients with preexisting shunts. Seventy-seven patients (49.7%) had procedures preceded by an ICP measurement within 4 weeks of venography, and in 66 (85.7%) of these patients, the ICP had been found to be elevated. CVPG was seen in 8.3% (n = 5) of the procedures in the 60 patients with a preexisting shunt and in 0% (n = 0) of the 11 procedures in the 77 patients with normal ICP (p < 0.001 for both). Noninvasive imaging (MR venography, CT venography) was assessed prior to venography in 112 (68.3%) of 164 cases, and dural venous sinus abnormalities were demonstrated in 73 (65.2%) of these cases; there was a trend toward CVPG (p = 0.07). Multivariate analysis demonstrated an increased likelihood of CVPG in patients with IIH (OR 4.97, 95% CI 1.71–14.47) and a decreased likelihood in patients with a preexisting shunt (OR 0.09, 95% CI 0.02–0.44). CONCLUSIONS CVPG is uncommon in IIH patients, rare in those with preexisting shunts, and absent in those with normal ICP.

Correlation between angiographic stenosis and physiologic venous sinus outflow obstruction in idiopathic intracranial hypertension

2018 ◽  
Vol 11 (1) ◽  
pp. 90-94 ◽  
Author(s):  
James L West ◽  
Garret P Greeneway ◽  
Rebecca M Garner ◽  
Carol A Aschenbrenner ◽  
Jasmeet Singh ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Venous Sinus ◽  
Arterial Stenosis ◽  
Non Invasive ◽  
Venous Phase ◽  
Sinus Stenosis ◽  
Clinically Significant

IntroductionThe relationship between degree of angiographic venous sinus stenosis and the trans-stenosis pressure gradient magnitude in idiopathic intracranial hypertension (IIH) is poorly understood. The present study aimed to assess the utility of angiography, venography, and non-invasive imaging (MRV or CTV) for the diagnosis and characterization of clinically significant VSS.MethodsRetrospective analysis of a prospectively collected database was performed to identify patients with medically refractory IIH who were evaluated by angiography and venous manometry for the presence of VSS with associated clinically significant pressure gradient. Angiographic stenosis was measured by two independent raters using novel methodology.ResultsThirty-seven patients met inclusion criteria for the study. In total, 70% of patients had clinically significant pressure gradients and were selected for stenting. The optimal percentage stenosis for detection of a significant pressure gradient was 34% stenosis on venous phase arteriography (sensitivity 0.81 and specificity 0.91) and 31% stenosis on venography (0.92 and 0.73). For every 10% increase in stenosis, an approximate increase in pressure gradient of 3.5 mmHg is seen. MRV/CTV had a calculated sensitivity of 0.42, and a negative predictive value of 22%.ConclusionThe degree of stenosis predictive of a clinically significant pressure gradient (30–35%) in the venous sinuses is considerably lower than the arterial stenosis at which pathologic hemodynamic alterations occur. While highly predictive of a venous pressure gradient when a stenosis is identified, non-invasive imaging does not appear to be a suitable diagnostic evaluation for the purpose of ruling out clinically significant cerebral VSS.

scholarly journals Transverse venous sinus stenting for idiopathic intracranial hypertension: Safety and feasibility

2018 ◽  
Vol 31 (5) ◽  
pp. 513-517 ◽  
Author(s):  
Jerry ME Koovor ◽  
Gloria V Lopez ◽  
Kalen Riley ◽  
Juan Tejada
Keyword(s):  
Computed Tomography ◽  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Transverse Sinus ◽  
Venous Sinus ◽  
Sinus Stenosis ◽  
The Mean ◽  
Computed Tomography Venography

Purpose Transverse sinus stenosis is commonly seen in patients with idiopathic intracranial hypertension. It is not clear whether it is the cause or the result of idiopathic intracranial hypertension. Stenting for idiopathic intracranial hypertension has been carried out in several prior series. Our goal was to evaluate the clinical and imaging follow-up results of patients with idiopathic intracranial hypertension that underwent stenting for this condition at our center. Materials and Methods We reviewed the clinical, venographic and follow-up imaging data in patients who underwent elective transverse sinus stenting during the period from 2011 to 2017. Results In total, 18 patients with idiopathic intracranial hypertension were identified. The mean lumbar cerebrospinal fluid opening pressure recorded was 408 mmH20. Overall, 16 patients met the inclusion criteria and underwent transverse sinus stenting. At venography, the mean pressure gradient across the dominant transverse sinus stenosis was 21 mmHg. The pressure gradient immediately after stenting in all of those measured was negligible. Following stenting, headaches improved in 10 of the 16 cases, with persistent headaches in four patients, one of which had persistent baseline migraines. All cases showed resolution of the papilledema on follow up. Follow-up imaging with computed tomography venography showed that the stents remained widely patent. The follow up in clinic was done for a mean period of 35.5 months. Follow up with computed tomography venography was done for a mean of 10.3 months. Conclusion Venous sinus stenting is a safe and effective procedure. It relieves papilledema in all cases and improves headaches in most cases.

scholarly journals Transient resolution of venous sinus stenosis after high-volume lumbar puncture in a patient with idiopathic intracranial hypertension

2018 ◽  
Vol 129 (1) ◽  
pp. 153-156 ◽  
Author(s):  
Thomas J. Buell ◽  
Daniel M. S. Raper ◽  
I. Jonathan Pomeraniec ◽  
Dale Ding ◽  
Ching-Jen Chen ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Lumbar Puncture ◽  
Idiopathic Intracranial Hypertension ◽  
High Volume ◽  
Transverse Sinus ◽  
Venous Sinus ◽  
Pressure Gradients ◽  
Cross Sectional ◽  
Sinus Stenosis

Stenosis of the transverse sinus (TS) and sigmoid sinus (SS), with a trans-stenosis pressure gradient, has been implicated in the pathophysiology of idiopathic intracranial hypertension (IIH). MRI has shown improvement in TS and SS stenosis after high-volume lumbar puncture (HVLP) in a subset of patients with IIH. The authors present the first report of an IIH patient with immediate post-HVLP TS and SS trans-stenosis pressure gradient reduction and an attendant increase in TS and SS cross-sectional area confirmed using intravascular ultrasonography (IVUS). Recurrence of the patient’s TS-SS stenosis coincided with elevated HVLP opening pressure, and venous sinus stent placement resulted in clinical improvement. This report suggests that TS and SS stenosis may be a downstream effect of elevated intracranial pressure in IIH, rather than its principal etiological mechanism. However, the authors hypothesize that endovascular stenting may obliterate a positive feedback loop involving trans-stenosis pressure gradients, and still benefit appropriately selected patients.

A descriptive study of venous sinus pressures and gradients in patients with idiopathic intracranial hypertension

2019 ◽  
Vol 12 (3) ◽  
pp. 320-325 ◽  
Author(s):  
Kyle M Fargen ◽  
Rebecca M Garner ◽  
Carol Kittel ◽  
Stacey Q Wolfe
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Venous Sinus ◽  
Pressure Gradients ◽  
Inclusion Criteria ◽  
Non Invasive ◽  
Sagittal Sinus ◽  
The Relationship

ObjectiveTo determine the relationship between normal physiologic and pathologic venous sinus pressures in patients with idiopathic intracranial hypertension (IIH), which is poorly understood.MethodsRetrospective analysis was performed to identify patients with medically refractory IIH who were evaluated by angiography and retrograde venography with venous manometry. Patients were further subdivided into groups based on anatomic factors.Results104 patients met inclusion criteria for the study. In the absence of non-invasive venographic screening, 58% of patients in this series were found to have pressure gradients of ≥8 mm Hg; 93% were located near the transverse-sigmoid sinus junction. Opening pressure (OP) is strongly predictive of superior sagittal sinus (SSS) pressures (p<0.001) and also of the presence of a pressure gradient ≥8 mm Hg (p<0.001). Twenty-three percent of patients with an OP <25 had a pressure gradient ≥8 mm Hg compared with 77% of patients with an OP ≥35. Analysis of patients with OP ≤20 suggests that SSS pressures in patients without IIH should be less than 16–18 mm Hg with total cranial gradients <5 mm Hg. Across all patients, a pressure decrement of approximately 1 mm Hg occurs with progressively more caudal transition across anatomic points of measurement.ConclusionsThis study describes intracranial and extracranial venous pressure measurements and gradients in different subgroups of patients with IIH. OP is highly predictive of intracranial venous pressures and significant venous pressure gradients.

Effect of Body Mass Index on Venous Sinus Pressures in Idiopathic Intracranial Hypertension Patients Before and After Endovascular Stenting

Neurosurgery ◽  
2017 ◽  
Vol 82 (4) ◽  
pp. 555-561 ◽  
Author(s):  
Daniel M S Raper ◽  
Dale Ding ◽  
Thomas J Buell ◽  
R Webster Crowley ◽  
Robert M Starke ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Body Mass ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Venous Hypertension ◽  
Venous Sinus ◽  
Morbidly Obese ◽  
Sinus Stenosis

Abstract BACKGROUND Elevated body mass index (BMI) has been correlated with worse outcomes after treatment for idiopathic intracranial hypertension (IIH). Venous sinus stenting (VSS) has emerged as a safe and effective treatment for a subset of patients with IIH and evidence of venous sinus stenosis. However, the association between BMI and the efficacy of VSS remains poorly characterized. OBJECTIVE To determine, in a retrospective cohort study, the effect of BMI on preoperative mean intracranial venous pressure (MVP) and post-VSS outcomes. METHODS We performed a retrospective evaluation of a prospectively collected database of patients with IIH and intracranial venous sinus stenosis who underwent VSS. Patient demographics and treatment factors, including pre- and postprocedural trans-stenosis pressure gradients, were analyzed to identify the relationship between BMI and outcomes after VSS. RESULTS Increasing BMI was significantly correlated with higher maximum MVP (P = .013) and higher trans-stenosis pressure gradient (P = .043) prior to treatment. The degrees of improvement in maximum MVP and pressure gradient after VSS were greatest for obese and morbidly obese patients (BMI &gt; 30 kg/m2). Maximum poststent MVP, clinical outcomes, and stent-adjacent stenosis requiring retreatment after VSS were not significantly associated with BMI. CONCLUSION We provide direct evidence for a positive correlation between BMI and intracranial venous pressure in patients with IIH. VSS affords a significantly greater amelioration of intracranial venous hypertension and stenosis for IIH patients with higher BMIs. As such, obesity should not be a deterrent for the use of VSS in the management of IIH.

scholarly journals Transverse venous stenting for the treatment of idiopathic intracranial hypertension, or pseudotumor cerebri

2018 ◽  
Vol 45 (1) ◽  
pp. E11 ◽  
Author(s):  
Justin M. Cappuzzo ◽  
Ryan M. Hess ◽  
John F. Morrison ◽  
Jason M. Davies ◽  
Kenneth V. Snyder ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Idiopathic Intracranial Hypertension ◽  
Transverse Sinus ◽  
Venous Sinus ◽  
Venous Stenting ◽  
Shunt Placement ◽  
The Mean ◽  
Visual Disturbances

OBJECTIVEIdiopathic intracranial hypertension (IIH) is a commonly occurring disease, particularly among young women of child-bearing age. The underlying pathophysiology for this disease has remained largely unclear; however, the recent literature suggests that focal outflow obstruction of the transverse sinus may be the cause. The purpose of this study was to report one group’s early experience with transverse venous sinus stenting in the treatment of IIH and assess its effectiveness.METHODSThe authors performed a retrospective chart review to identify patients who had undergone stenting of an outflow-obstructed transverse venous sinus for the treatment of IIH at Gates Vascular Institute between January 2015 and November 2017. Patient demographic data of interest included age, sex, BMI, and history of smoking, hypertension, obstructive sleep apnea, hormonal contraceptive use, and acetazolamide therapy. Each patient’s presenting signs and symptoms and whether those symptoms improved with treatment were reviewed. The average opening lumbar puncture (LP) pressure preprocedure, average pressure gradient across the obstructed segment prior to stenting, treatment failure rate (need for shunt placement), and mean follow-up period were calculated.RESULTSOf the 18 patients who had undergone transverse venous stenting for IIH, 16 (88.9%) were women. The mean age of all the patients was 38.3 years (median 38 years). Mean BMI was 34.2 kg/m2 (median 33.9 kg/m2). Presenting symptoms were headache (16 patients [88.9%]), visual disturbances (13 patients [72.2%]), papilledema (8 patients [44.4%]), tinnitus (3 patients [16.7%]), and auditory bruit (3 patients [16.7%]). The mean opening LP pressure pre-procedure was 35.6 cm H2O (median 32 cm H2O). The mean pressure gradient measured proximally and distally to the area of focal obstruction within the transverse sinus was 16.5 cm H2O (median 15 cm H2O). Postprocedurally, 14 patients (77.8%) continued to have headaches; 6 (33.3%) continued to have visual disturbances. No patients continued to have auditory bruit (0%) or papilledema (0%). One patient (5.6%) had new-onset tinnitus postprocedure. Overall improvement of symptoms was noted in 16 patients (88.9%) postprocedure, with 1 patient (5.6%) requiring shunt placement and 2 other patients (11.1%) requiring postprocedural LP to monitor intracranial pressure to determine candidacy for further surgical interventions to treat residual symptoms. The mean duration of follow-up was 194.2 days.CONCLUSIONSTransverse sinus stenting is a rapidly developing technique that has shown good effectiveness and safety in the literature. Authors of the present study found that stenting a flow-obstructed transverse sinus in patients with IIH was a safe and effective way to treat the condition.

Venous Sinus Pulsatility and the Potential Role of Dural Incompetence in Idiopathic Intracranial Hypertension

Neurosurgery ◽  
2012 ◽  
Vol 71 (4) ◽  
pp. 877-884 ◽  
Author(s):  
Marc A. Lazzaro ◽  
Ziad Darkhabani ◽  
Bernd F. Remler ◽  
Sang H. Hong ◽  
Thomas J. Wolfe ◽  
...  
Keyword(s):  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Stent Implantation ◽  
Idiopathic Intracranial Hypertension ◽  
Potential Role ◽  
Transverse Sinus ◽  
Venous Sinus ◽  
Dural Sinus ◽  
Complete Understanding

Abstract BACKGROUND: Idiopathic intracranial hypertension (IIH) remains a poorly understood and therapeutically challenging disease. Enthusiasm has emerged for endovascular therapy with stent reconstruction of dural sinus narrowing; however, a complete understanding of the hydrodynamic dysequilibrium is lacking. OBJECTIVE: To review and characterize catheter manometry findings including pulsatility changes within the venous sinuses in IIH. METHODS: Cases of venous sinus stent implantation for IIH were retrospectively reviewed. RESULTS: Three cases of venous sinus stent implantation for treatment of IIH are reported. All cases demonstrated severe narrowing (&gt;70%) within the transverse sinus and a high pressure gradient across the lesion (&gt;30 mm Hg). Stent implantation resulted in pulsatility attenuation, correction of pressure gradient, and improvement of flow. CONCLUSION: We report the finding of high venous sinus pulsatility attenuation after stent implantation for dural sinus narrowing and propose the hypothesis that this finding is a marker of advanced dural sinus incompetence. This characteristic may be useful in identifying patients who would benefit from endovascular stent remodeling.

scholarly journals Fifty shades of gradients: does the pressure gradient in venous sinus stenting for idiopathic intracranial hypertension matter? A systematic review

2019 ◽  
Vol 130 (3) ◽  
pp. 999-1005 ◽  
Author(s):  
Cameron M. McDougall ◽  
Vin Shen Ban ◽  
Jeffrey Beecher ◽  
Lee Pride ◽  
Babu G. Welch
Keyword(s):  
Systematic Review ◽  
Pressure Gradient ◽  
Intracranial Hypertension ◽  
Stent Placement ◽  
Idiopathic Intracranial Hypertension ◽  
Venous Pressure ◽  
Venous Sinus ◽  
Stepwise Logistic Regression ◽  
Pressure Gradients ◽  
Sinus Stenosis

OBJECTIVEThe role of venous sinus stenting (VSS) for idiopathic intracranial hypertension (IIH) is not well understood. The aim of this systematic review is to attempt to identify subsets of patients with IIH who will benefit from VSS based on the pressure gradients of their venous sinus stenosis.METHODSMEDLINE/PubMed was searched for studies reporting venous pressure gradients across the stenotic segment of the venous sinus, pre- and post-stent pressure gradients, and clinical outcomes after VSS. Findings are reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines.RESULTSFrom 32 eligible studies, a total of 186 patients were included in the analysis. Patients who had favorable outcomes had higher mean pressure gradients (22.8 ± 11.5 mm Hg vs 17.4 ± 8.0 mm Hg, p = 0.033) and higher changes in pressure gradients after stent placement (19.4 ± 10.0 mm Hg vs 12.0 ± 6.0 mm Hg, p = 0.006) compared with those with unfavorable outcomes. The post-stent pressure gradients between the 2 groups were not significantly different (2.8 ± 4.0 mm Hg vs 2.7 ± 2.0 mm Hg, p = 0.934). In a multivariate stepwise logistic regression controlling for age, sex, body mass index, CSF opening pressure, pre-stent pressure gradient, and post-stent pressure gradient, the change in pressure gradient with stent placement was found to be an independent predictor of favorable outcome (p = 0.028). Using a pressure gradient of 21 as a cutoff, 81/86 (94.2%) of patients with a gradient > 21 achieved favorable outcomes, compared with 82/100 (82.0%) of patients with a gradient ≤ 21 (p = 0.022).CONCLUSIONSThere appears to be a relationship between the pressure gradient of venous sinus stenosis and the success of VSS in IIH. A randomized controlled trial would help elucidate this relationship and potentially guide patient selection.

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