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Mahnken AH, Bruners P, Kinzel S, Das M, Mühlenbruch G, Günther RW, Wildberger JE. MSCT Vitalitätsdiagnostik in verschiedenen Phasen des Myokardinfarktes: tierexperimentelle Ergebnisse. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-976943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Hohl C, Böse J, Brunner T, Banckwitz R, Mühlenbruch G, Wildberger JE, Mahnken AH, Günther RW. Angiographische CT: Messung der effektiven Patientendosis. ROFO-FORTSCHR RONTG 2007. [DOI: 10.1055/s-2007-977073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Hohl C, Wildberger JE, Süss C, Thomas C, Mühlenbruch G, Schmidt T, Honnef D, Günther RW, Mahnken AH. Radiation dose reduction to breast and thyroid during MDCT: effectiveness of an in-plane bismuth shield. Acta Radiol 2006; 47:562-7. [PMID: 16875333 DOI: 10.1080/02841850600702150] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate dose reduction and image deterioration using in-plane bismuth breast-shielding and thyroid-shielding for MDCT. MATERIAL AND METHODS Skin and organ doses of thyroid and breast were measured with thermoluminescent dosimeters in a female Alderson-Rando Phantom with and without a 4-ply in-plane bismuth shield. Routine neck (120 kVp, 150 mAs(eff); 16 x 1.5 mm) and chest (120 kVp, 100 mAs(eff); 16 x 1.5 mm) scan protocols were simulated on a 16-row MDCT scanner in three different settings: without shielding, with the shield directly on the surface, and with a 1-cm-thick cotton spacer between surface and shield. Image noise was quantified and compared using the t test. RESULTS On average, shielding resulted in a 47% organ-dose reduction for the thyroid and 32% for the breast. Placement of the spacer between shield and surface had no significant impact on the measured doses, but significantly decreased the image noise (P < 0.05). CONCLUSION In-plane bismuth breast and thyroid shielding significantly decreases radiation dose in MDCT without deteriorating image quality.
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Wildberger JE, Katoh M, Fussen R, Günther RW. [Technical Note: Subclavian artery misplacement of a 12F Shaldon catheter: percutaneous repair with a local closure device under temporary balloon tamponade]. ROFO-FORTSCHR RONTG 2006; 178:605-9. [PMID: 16703496 DOI: 10.1055/s-2006-926629] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A case of subsequent percutaneous repair using a local closure device with a collagen block (VasoSeal(R)) and temporary balloon tamponade after inadvertent subclavian artery misplacement of a 12F Shaldon catheter is reported. Balloon occlusion safely prevented displacement of collagen into the vascular lumen by occluding the 12F entry site. Furthermore, collagen-induced coagulation was facilitated.
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Hohl C, Mühlenbruch G, Wildberger JE, Leidecker C, Süss C, Schmidt T, Günther RW, Mahnken AH. Estimation of radiation exposure in low-dose multislice computed tomography of the heart and comparison with a calculation program. Eur Radiol 2006; 16:1841-6. [PMID: 16456650 DOI: 10.1007/s00330-005-0124-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Revised: 11/22/2005] [Accepted: 12/12/2005] [Indexed: 11/30/2022]
Abstract
The purpose of this study was to evaluate the achievable organ dose savings in low-dose multislice computed tomography (MSCT) of the heart using different tube voltages (80 kVp, 100 kVp, 120 kVp) and compare it with calculated values. A female Alderson-Rando phantom was equipped with thermoluminescent dosimeters (TLDs) in five different positions to assess the mean doses within representative organs (thyroid gland, thymus, oesophagus, pancreas, liver). Radiation exposure was performed on a 16-row MSCT scanner with six different routine scan protocols: a 120-kV and a 100-kV CT angiography (CTA) protocol with the same collimation, two 120-kV Ca-scoring (CS) protocols with different collimations and two 80-kV CS protocols with the same collimation as the 120-kV CS protocols. Each scan protocol was repeated five times. The measured dose values for the organs were compared with the values calculated by a commercially available computer program. Directly irradiated organs, such as the esophagus, received doses of 34.7 mSv (CTA 16x0.75 120 kVp), 21.9 mSv (CTA 16x0.75 100 kVp) and 4.96 mSv (CS score 12x1.5 80 kVp), the thyroid as an organ receiving only scattered radiation collected organ doses of 2.98 mSv (CTA 16x0.75 120 kVp), 1.97 mSv (CTA 16x0.75 100 kVp) and 0.58 mSv (CS score 12x1.5 80 kVp). The measured relative organ dose reductions from standard to low-kV protocols ranged from 30.9% to 55.9% and were statistically significant (P<0.05). The comparison with the calculated organ doses showed that the calculation program can predict the relative dose reduction of cardiac low photon-energy protocols precisely.
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Mahnken AH, Mühlenbruch G, Seyfarth T, Flohr T, Stanzel S, Wildberger JE, Günther RW, Kuettner A. 64-slice computed tomography assessment of coronary artery stents: a phantom study. Acta Radiol 2006; 47:36-42. [PMID: 16498931 DOI: 10.1080/02841850500406779] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare the use of a new 64-slice computed tomography (CT) scanner with 16-slice CT in the visualization of coronary artery stent lumen. MATERIAL AND METHODS Eight different coronary artery stents, each with a diameter of 3 mm, were placed in a static chest phantom. The phantom was positioned in the CT gantry at an angle of 0 degrees and 45 degrees towards the z-axis and examined with both a 64-slice and a 16-slice CT scanner. Effective slice thickness was 0.6 mm with 64-slice CT and 1 mm with 16-slice CT. A reconstruction increment of 0.3 mm was applied in both scanners. Image quality was assessed visually using a 5-point grading scale. Stent diameters were measured and compared using paired Wilcoxon tests. RESULTS Artificial lumen reduction was significantly less with 64-slice than with 16-slice CT. Average visible stent lumen was 53.4% using 64-slice CT and 47.5% with 16-slice MSCT. Most severe artifacts were seen in stents with radiopaque markers. Using 64-slice CT, image noise increased by approximately 30% due to thinner slice thickness. CONCLUSION Improved spatial resolution of 64-slice CT resulted in superior assessment of coronary artery stent lumen compared to 16-slice CT. However, a relevant part of the stent lumen is still not assessable with multi-slice CT.
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Honnef D, Wildberger JE, Das M, Hohl C, Mahnken A, Schnöring H, Vázquez-Jiménez J, Günther RW, Staatz G. Dosisreduzierte 16-Schicht-Multidetektor-Spiralcomputertomographie bei Säuglingen und Kleinkindern mit bronchoskopischem Verdacht auf vaskulär bedingte Trachealstenosen - erste klinische Ergebnisse. ROFO-FORTSCHR RONTG 2006; 178:425-31. [PMID: 16607590 DOI: 10.1055/s-2006-926537] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate the diagnostic accuracy of contrast-enhanced dose-reduced 16-slice multidetector-row CT (MDCT) in newborns and infants with fiberoptic bronchoscopically suspected vascular-induced tracheal stenosis. MATERIALS AND METHODS 12 children (4 days to 3 years, 1.2 - 13.5 kg body weight) were examined using i. v. contrast-enhanced 16-slice MDCT (SOMATOM Sensation 16, Forchheim, Germany) without breath-hold and under sedation (11/12). All MDCTs were performed with a dose reduction. The beam collimation was 16 x 0.75 mm, except in the case of one child. MPRs along the tracheal axis in the x-, y- and z-directions and volume-rendering-reconstructions (VRTs) were calculated based on a secondary raw data set in addition to conventional axial slices. 2 radiologists used a three-point grade scale to evaluate the image quality, motion, and contrast media artifacts as well as the usefulness of the 2D- and 3D-reconstructions for determining the diagnosis. Statistical analysis was performed on the basis of a Kappa test. RESULTS In all cases the cause of the fiberoptic bronchoscopically suspected tracheal stenosis was revealed: compression due to the brachiocephalic trunk (n = 7), double aortic arch (n = 2), lusorian artery (n = 1), vascular compression of the left main bronchus (n = 2). In 3 patients further thoracic anomalies, such as tracheobronchial (n = 2), and vascular (n = 2) and vertebral (n = 1) anomalies were found. The attenuation in the anomalous vessels was 307 +/- 140 HU. The image noise was 9.8 +/- 1.9 HU. The mean dose reduction was 82.7 +/- 3.2 % compared to a standard adult thoracic CT. All examinations were rated as diagnostically good (median 1, range 1, k = 1). 3D images did not show any stair artifacts (median 2, range 1 - 2, k = 1). The image noise was minor to moderate and hardly any motion artifacts were seen (median 1, range 1 - 2, k = 0.8). Contrast media artifacts were rated zero to minor (median 1.5, range 1 - 2, k = 0.676). MPRs (median 1, range 1, k = 1) and VRTs (median 1, range 1, k = 1) were found to be useful for diagnosis. Subsequent vascular surgery was performed on 8 patients. CONCLUSION Contrast-enhanced dose-reduced 16-slice MDCT is effective for demonstrating the cause of fiberoptic bronchoscopically suspected vascular-induced tracheal stenosis even in very small and severely ill children despite the small contrast media amount and free breathing.
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Hohl C, Süß C, Wildberger JE, Thomas C, Schmidt T, Mühlenbruch G, Günther RW, Mahnken AH. Belichtungsautomatik in der Abdomen-CT: Eine effektive Maßnahme zur Dosisreduktion. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Das M, Mühlenbruch G, Mahnken AH, Hohl C, Honnef D, Gündel L, Bakai A, Günther RW, Wildberger JE. Genauigkeit der Computer-assistierten Volumetrie von Lungenrundherden. Vergleich der Messungen anhand von Datensätzen unterschiedlicher CT Scanner (Einzelschicht bis Mehrschicht-Spiral CT). ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Wildberger JE. Pulmonalarterien und Perfusion. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Hohl C, Süß C, Wildberger JE, Schmidt T, Mühlenbruch G, Günther RW, Mahnken AH. Dosisreduktion bei CT-gesteuerten Thorax-Interventionen. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Mahnken AH, Klotz E, Lautenschläger M, Scheuering M, Rinck D, Mühlenbruch G, Günther RW, Wildberger JE. Myokardinfarktdarstellung inder MSCT mittels modellbasierter Segmentierung und perfusionsgewichteter Farbcodierung. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Das M, Mühlenbruch G, Salganicoff M, Honnef D, Heinen S, Mahnken AH, Bakai A, Günther RW, Wildberger JE. Vergleich der Sensitivität der Computer-assistierten Detektion (CAD) von Lungenrundherden bei Niedrigdosis- und Standarddosis Mehrschicht-Spiral CT (MSCT) Untersuchungen. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Das M, Mühlenbruch G, Mahnken AH, Günther RW, Wildberger JE. Bronchialkarzinom: Früherkennung – aktueller Stand. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Honnef D, Wildberger JE, Haras G, Hohl C, Mühlenbruch G, Staatz G, Barker M, Günther RW, Mahnken AH. Prospektive Evaluierung der Bildqualität anhand einer Patienten-Bildergalerie zur Dosisreduktion bei 16-Mehrschichtspiral-Computertomographien (MSCT). ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Mühlenbruch G, Wildberger JE, Das M, Hohl C, Seyfarth T, Soo CS, Pregalathan N, Günther RW, Mahnken AH. Diagnostischer Wert der 64-Zeilen Mehrschichtspiral CT des Herzens bei symptomatischen Patienten. ROFO-FORTSCHR RONTG 2006. [DOI: 10.1055/s-2006-940730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Mühlenbruch G, Wildberger JE, Koos R, Das M, Thomas C, Ruhl K, Niethammer M, Floh TG, Stanzel S, Günther RW, Mahnken AH. Calcium scoring of aortic valve calcification in aortic valve stenosis with a multislice computed tomography scanner: non-enhanced versus contrast-enhanced studies. Acta Radiol 2005; 46:561-6. [PMID: 16334836 DOI: 10.1080/02841850510021698] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE Previous studies have shown a positive correlation between amount of aortic valve calcification (AVC) and degree of aortic valve stenosis (AVS). We have investigated whether calcium scoring of AVC from contrast-enhanced images is reliable. MATERIAL AND METHODS Nineteen patients with suspected AVS underwent retrospectively ECG-gated multislice computed tomography (MSCT). Standardized scan protocols were applied prior to (120 KV, 133 mAseff) and after (120 KV, 500 mAseff) the administration of non-ionic contrast material. Image reconstruction was performed at 60% of the RR interval (slice thickness 3 mm, reconstruction increment 2 mm). AVC was quantified using Agatston score and calcium mass. The number of lesions was calculated. All nonenhanced images were scored using thresholds of 130 HU and 350 HU. Contrast-enhanced images were assessed with a threshold of 350 HU exclusively. RESULTS Fifteen patients with AVCs were included in the statistical analysis. The mean Agatston score (calcium mass) in non-enhanced images was 2888.4 +/- 2844.4 (694.2 mg +/- 869.3 mg). Altering the threshold from 130 HU to 350 HU led to a 58.2% (30.5%) decrease in the AVC score (P values < 0.001). Contrast-enhanced images showed an increased Agatston score (calcium mass) of 56.2% (33.5%) compared to non-enhanced images (P values <0.05) with the same threshold of 350 HU. CONCLUSION Quantification of AVC from contrast-enhanced images is not reliable, as contrast material simulates calcification.
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Wildberger JE. CT: Funktionelle Bildgebung der Lunge (Ventilation/Perfusion). ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Das M, Mühlenbruch G, Mahnken A, Felten MK, Kraus T, Flohr TG, Günther RW, Wildberger JE. Lungenkrebsscreening in Asbest-exponierten Hochrisikopatienten mithilfe der Niedrigdosis-Mehrschichtspiral-CT. Ergebnisse der Erstuntersuchung und der einjährigen Verlaufskontrolle. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mahnken A, Koos R, Katoh M, Wildberger JE, Spüntrup E, Busch P, Kühl H, Günther RW. Myokardiale Vitalitätsdiagnostik in der Mehrschicht-Spiral-CT. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mahnken A, Flohr T, Seyfarth T, Mühlenbruch G, Das M, Günther RW, Wildberger JE, Küttner A. 64-Schicht-Spiral-CT für die Beurteilung von Koronarstents im Vergleich zur 16-Schicht-Spiral-CT: In-vitro-Untersuchungen. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mahnken A, Katoh M, Bruners P, Spüntrup E, Wildberger JE, Heuschmid M, Günther RW, Bücker A. 16-Schicht-Spiral-CT zur Beurteilung der linksventrikulären Funktion und Wandbewegung nach Myokardinfarkt im Vergleich zur MRT: tierexperimentelle Untersuchungen. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Ruhl KM, Das M, Mühlenbruch G, Flohr TG, Koos R, Wildberger JE, Günther RW, Mahnken A. Variabilität der Messung von Aortenklappenkalzifikationen mit 16-Zeilen-Spiral-CT. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Das M, Mühlenbruch G, Mahnken A, Flohr TG, Gündel L, Günther RW, Wildberger JE. Verbesserte Sensitivität bei der Detektion kleiner pulmonaler Rundherde durch Computer-assistierte Diagnose. Vergleich zweier CAD-Systeme. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mühlenbruch G, Koos R, Wildberger JE, Das M, Flohr T, Zarse M, Günther RW, Mahnken A. Bildgebung der Koronarvenen: Mehrschicht-Spiral-CT im Vergleich zur konventionellen Koronar-Sinus-Angiographie. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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