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Hiroshi Honda - One of the best experts on this subject based on the ideXlab platform.
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comparison of positron emission tomography diffusion weighted imaging pet dwi registration quality in a pet mr scanner zoomed dwi vs conventional dwi
Journal of Magnetic Resonance Imaging, 2016Co-Authors: Koji Sagiyama, Yuji Watanabe, Ryotaro Kamei, Shingo Baba, Hiroshi HondaAbstract:Purpose To compare zoomed diffusion-weighted imaging (z-DWI) with reduced field of view (FOV) by spatially selective radiofrequency pulses and conventional echo planar imaging (EPI) DWI (c-DWI) with regard to registration quality using positron emission tomography / magnetic resonance (PET/MR) in patients with malignant tumors. Materials and Methods Fludeoxyglucose (18F) PET imaging, c-DWI, and z-DWI were conducted simultaneously in 21 patients with known or suspected malignancy using a PET/MR system. A fusion image showing the largest tumor area was generated for analysis. Registration accuracy between PET and DWI was assessed based on the area of maximum overlap and central point displacement of the tumor. EPI factor, echo time (TE), matching area, and displacement were compared between c-DWI and z-DWI by paired t-test. Agreement of apparent diffusion coefficient (ADC) acquired by the two sequences were also assessed with linear regression s and Bland–Altman plot analysis. Results Thirty-two lesions were detected on both PET and DWI (mean size 536.3 ± 471.8 mm2). At least one lesion was found in all subjects. In all cases, EPI factor was smaller with z-DWI than c-DWI (43.1 ± 15.6 vs. 62.0 ± 10.0, P < 0.0001), and TE was also shorter for z-DWI (53.6 ± 3.6 msec vs. 65.2 ± 3.6 msec, P < 0.0001). Registration accuracy was better with z-DWI in 30 of 32 lesions (93.8%), and both average matching area and central point displacement were significantly improved (79.8 ± 18.1% vs. 61.8 ± 22.9%, P < 0.0001 and 3.92 ± 2.69 mm vs. 7.51 ± 4.07 mm, P < 0.0001). ADC values calculated with c-DWI and z-DWI showed good agreement. Conclusion Zoomed DWI reduces image distortion and provides better registration accuracy with PET images. J. Magn. Reson. Imaging 2015.
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Comparison of positron emission tomography diffusion-weighted imaging (PET/DWI) registration quality in a PET/MR scanner: Zoomed DWI vs. Conventional DWI.
Journal of magnetic resonance imaging : JMRI, 2015Co-Authors: Koji Sagiyama, Yuji Watanabe, Ryotaro Kamei, Shingo Baba, Hiroshi HondaAbstract:Purpose To compare zoomed diffusion-weighted imaging (z-DWI) with reduced field of view (FOV) by spatially selective radiofrequency pulses and conventional echo planar imaging (EPI) DWI (c-DWI) with regard to registration quality using positron emission tomography / magnetic resonance (PET/MR) in patients with malignant tumors. Materials and Methods Fludeoxyglucose (18F) PET imaging, c-DWI, and z-DWI were conducted simultaneously in 21 patients with known or suspected malignancy using a PET/MR system. A fusion image showing the largest tumor area was generated for analysis. Registration accuracy between PET and DWI was assessed based on the area of maximum overlap and central point displacement of the tumor. EPI factor, echo time (TE), matching area, and displacement were compared between c-DWI and z-DWI by paired t-test. Agreement of apparent diffusion coefficient (ADC) acquired by the two sequences were also assessed with linear regression s and Bland–Altman plot analysis. Results Thirty-two lesions were detected on both PET and DWI (mean size 536.3 ± 471.8 mm2). At least one lesion was found in all subjects. In all cases, EPI factor was smaller with z-DWI than c-DWI (43.1 ± 15.6 vs. 62.0 ± 10.0, P < 0.0001), and TE was also shorter for z-DWI (53.6 ± 3.6 msec vs. 65.2 ± 3.6 msec, P < 0.0001). Registration accuracy was better with z-DWI in 30 of 32 lesions (93.8%), and both average matching area and central point displacement were significantly improved (79.8 ± 18.1% vs. 61.8 ± 22.9%, P < 0.0001 and 3.92 ± 2.69 mm vs. 7.51 ± 4.07 mm, P < 0.0001). ADC values calculated with c-DWI and z-DWI showed good agreement. Conclusion Zoomed DWI reduces image distortion and provides better registration accuracy with PET images. J. Magn. Reson. Imaging 2015.
Jamshed Bomanji - One of the best experts on this subject based on the ideXlab platform.
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18F Fludeoxyglucose pet ct in the evaluation of large vessel vasculitis diagnostic performance and correlation with clinical and laboratory parameters
British Journal of Radiology, 2012Co-Authors: Nikolaos D. Papathanasiou, L J Menezes, A Almuhaideb, M Shastry, H Beynon, Jamshed BomanjiAbstract:Objective: To investigate the diagnostic performance of 18F-Fludeoxyglucose (18F-FDG) positron emission tomography (PET)/CT in patients with suspected large-vessel vasculitis and its potential to evaluate the extent and activity of disease. Methods: 78 consecutive patients (mean age 63 years; 53 females) with suspected large-vessel vasculitis were evaluated with 18F-FDG PET/CT. 18F-FDG uptake in the aorta and major branches was visually graded using a four-point scale and quantified with standardised uptake values (SUVmax). According to clinical diagnosis, patients were classified into three groups: (a) steroid-naive, large-vessel vasculitis (16 patients), (b) vasculitis on steroid treatment (18 patients) and (c) no evidence of vasculitis (44 patients). Analysis of variance and linear regression were used to investigate the association of 18F-FDG uptake with clinical diagnosis and inflammatory markers. Results: 18F-FDG PET/CT was positive (visual uptake ≥2; equal to or greater than liver) in all patients ...
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18F-Fludeoxyglucose PET/CT in the evaluation of large-vessel vasculitis: diagnostic performance and correlation with clinical and laboratory parameters.
The British journal of radiology, 2011Co-Authors: Nikolaos D. Papathanasiou, L J Menezes, A Almuhaideb, M Shastry, H Beynon, Jamshed BomanjiAbstract:Objective: To investigate the diagnostic performance of 18F-Fludeoxyglucose (18F-FDG) positron emission tomography (PET)/CT in patients with suspected large-vessel vasculitis and its potential to evaluate the extent and activity of disease. Methods: 78 consecutive patients (mean age 63 years; 53 females) with suspected large-vessel vasculitis were evaluated with 18F-FDG PET/CT. 18F-FDG uptake in the aorta and major branches was visually graded using a four-point scale and quantified with standardised uptake values (SUVmax). According to clinical diagnosis, patients were classified into three groups: (a) steroid-naive, large-vessel vasculitis (16 patients), (b) vasculitis on steroid treatment (18 patients) and (c) no evidence of vasculitis (44 patients). Analysis of variance and linear regression were used to investigate the association of 18F-FDG uptake with clinical diagnosis and inflammatory markers. Results: 18F-FDG PET/CT was positive (visual uptake ≥2; equal to or greater than liver) in all patients ...
A K - One of the best experts on this subject based on the ideXlab platform.
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effective dose to staff members in a positron emission tomography ct facility using zirconium 89
British Journal of Radiology, 2013Co-Authors: K S Alzimami, A KAbstract:Objective:Positron emission tomography (PET) using zirconium-89 (89Zr) is complicated by its complex decay scheme. In this study, we quantified the effective dose from 89Zr and compared it with fluorine-18 Fludeoxyglucose (18F-FDG).Methods:Effective dose distribution in a PET/CT facility in Riyadh was calculated by Monte Carlo simulations using MCNPX. The positron bremsstrahlung, the annihilation photons, the delayed gammas from 89Zr and those emissions from 18F-FDG were modelled in the simulations but low-energy characteristic X-rays were ignored.Results:On the basis of injected activity, the dose from 89Zr was higher than that of 18F-FDG. However, the dose per scan from 89Zr became less than that from 18F-FDG near the patient, owing to the difference in injected activities. In the corridor and control rooms, the 89Zr dose was much higher than 18F-FDG, owing to the difference in attenuation by the shielding materials.Conclusion:The presence of the high-energy photons from 89Zr-labelled immuno-PET radioph...
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Effective dose to staff members in a positron emission tomography/CT facility using zirconium-89
British Journal of Radiology, 2013Co-Authors: K S Alzimami, A KAbstract:Objective:Positron emission tomography (PET) using zirconium-89 (89Zr) is complicated by its complex decay scheme. In this study, we quantified the effective dose from 89Zr and compared it with fluorine-18 Fludeoxyglucose (18F-FDG).Methods:Effective dose distribution in a PET/CT facility in Riyadh was calculated by Monte Carlo simulations using MCNPX. The positron bremsstrahlung, the annihilation photons, the delayed gammas from 89Zr and those emissions from 18F-FDG were modelled in the simulations but low-energy characteristic X-rays were ignored.Results:On the basis of injected activity, the dose from 89Zr was higher than that of 18F-FDG. However, the dose per scan from 89Zr became less than that from 18F-FDG near the patient, owing to the difference in injected activities. In the corridor and control rooms, the 89Zr dose was much higher than 18F-FDG, owing to the difference in attenuation by the shielding materials.Conclusion:The presence of the high-energy photons from 89Zr-labelled immuno-PET radioph...
Ghoufrane Tlili - One of the best experts on this subject based on the ideXlab platform.
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Infections in patients using ventricular-assist devices: Comparison of the diagnostic performance of ^18F-FDG PET/CT scan and leucocyte-labeled scintigraphy
Journal of Nuclear Cardiology, 2019Co-Authors: Carole Vaugelade, Charles Mesguich, Karine Nubret, Fabrice Camou, Carine Greib, Gael Dournes, Frédéric Debordeaux, Elif Hindie, Laurent Barandon, Ghoufrane TliliAbstract:背景 左心室辅助装置 (LVAD) 越来越多的应用于重度心力衰竭患者。然而, 设备相关的感染有着重要的发病率和死亡率, 并且对其诊断和治疗均是一项挑战。对于 LVAD 相关感染, 核医学影像可扮演的角色一直没有完善。本研究针对装备有连续流式 LVAD 的感染病人,对比了 ^18F-FDG PET/CT 造影术和放射性标记白细胞闪烁扫描法对感染诊断的准确性。 方法 从一个前瞻性的数据库, 入选了24名疑似设备感染的 LVAD 病人, 并回顾性的分析了放射性标记白细胞闪烁扫描法和 ^18F-FDG PET/CT 的诊断表现。所有病人都常规进行了上述两种检查。利用 ISHLT 标准对感染情况进行评估。 结果 在入选的 24 名病人中, 15 名有明确的 VAD 感染 (5 名心脏的 LVAD 和 10 名动力传动系统装置), 6 名有 VAD 相关的感染,另外3名有 VAD 无关的感染。对于 ^18F-FDG PET/CT 诊断方法,其敏感性,特异性,阳性预测值,阴性预测值和准确率分别为: 95.2%, 66.7%, 95.2%, 66.7%, 和 91.6%; 而对于白细胞闪烁扫描诊断方法, 其敏感性, 特异性, 阳性预测值,阴性预测值和准确率分别为: 71.4%, 100%, 100%, 33.3% 和 75%。相比于白细胞闪烁扫描, ^18F-FDG PET/CT 明显展现出较高的敏感性 (p=0.01)。 结论 ^18F-FDG PET/CT 和白细胞闪烁扫描 SPECT 对于 LVAD 感染的诊断具有很好的表现。^18F-FDG PET/CT 展现出较高的敏感性,可以作为核医学的首要检查。 Background The usage of left-ventricular-assist device (LVAD) is increasing in patients presenting with advanced heart failure. However, device-related infections are a challenge to recognize and to treat, with an important morbidity and mortality rate. The role of nuclear medicine imaging remains not well established for LVAD infections. The present study compared the accuracy of positron emission tomography/computed tomography with ^18F-Fludeoxyglucose (^18F-FDG PET/CT) and radiolabeled leucocyte scintigraphy for the diagnosis of infections in patients supported with a continuous-flow LVAD. Methods From a prospectively maintained database, we retrospectively analyzed the diagnostic performance of radiolabeled leucocyte scintigraphy and ^18F-FDG PET/CT in 24 patients who had a LVAD with a suspected device-related infection. Both examinations were routinely performed in all patients. Infection was assessed by the International Society for Heart and Lung Transplantation criteria. Results Twenty-four patients were included: 15 had a specific VAD infection (5 cardiac-LVAD and 10 driveline), 6 had a VAD-related infection, while 3 patients had a non-VAD-related infection. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 95.2%, 66.7%, 95.2%, 66.7%, and 91.6%, respectively, for ^18F-FDG-PET; and 71.4%, 100%, 100%, 33.3%, and 75%, respectively, for leucocyte scintigraphy. ^18F-FDG PET/CT showed significantly higher sensitivity ( P = 0.01) than leucocyte scintigraphy. Conclusion ^18F-FDG PET/CT and radiolabeled leucocyte scintigraphy single-photon emission computed tomography carry high performance in the diagnostic of LVAD infections. ^18F-FDG PET/CT shows significantly higher sensitivity and could be proposed as first-line nuclear medicine procedure. Contexte L’utilisation du dispositif d’assistance ventriculaire gauche (DAVG) est en utilisation croissante chez les patients avec insuffisance cardiaque avancée. Cependant, les infections liées au dispositif sont un défi à reconnaître et à traiter en raison d’ un taux de morbidité et de mortalité important. Le rôle de l’imagerie de médecine nucléaire n’est pas encore bien établi pour les infections secondaires au DAVG. La présente étude compare la précision de la tomographie par émission de positrons / tomodensitométrie au 18F-fluorodéoxyglucose (18F-FDG TEP/TDM) et la scintigraphie leucocytaire radio-marquée pour le diagnostic d’infections chez des patients porteurs par un DAVG à flux continu. Méthodes A partir d’une base de données complétée de manière prospective nous avons analysé rétrospectivement les performances diagnostiques de la scintigraphie leucocytaire radio-marquée et de la TEP / TDM au 18F-FDG chez 24 patients ayant un DAVG avec une infection suspectée liée à l’appareillage. Les deux types d’examens scintigraphiques ont été systématiquement réalisé chez tous les patients. Le diagnostic d’infection fut établi selon les critères ISHLT. Résultats Parmi les 24 patients inclus, 15 avaient une infection spécifique de l’appareillage AVG (5 au niveau de la pompe et/ou canule d’insertion myocardique) et 10 au niveau du driveline, 6 avaient une infection indirectement liée à l’appareillage AVG, tandis que 3 patients avaient une infection non liée au DAVG. La sensibilité, la spécificité, la valeur prédictive positive, la valeur prédictive négative et la précision étaient de 95,2%, 66,7%, 95,2%, 66,7% et 91,6%, respectivement, pour le 18F-FDG-PET et 71,4%, 100%, 100%, 33,3 %, et 75%, respectivement, pour la scintigraphie leucocytaire. La TEP / TDM au 18F-FDG a montré une sensitivité significativement plus élevée (p = 0,01) que la scintigraphie leucocytaire. Conclusion 18F-FDG TEP/TDM et scintigraphie leucocytaire radio-marquée SPECT s’avèrent très efficaces pour le diagnostic des infections à DVAG. La TEP/TDM au 18F-FDG montre une sensibilité significativement plus élevée et pourrait être proposée en tant que la procédure de médecine nucléaire de premier choix. Antecedentes El uso de dispositivos de asistencia ventricular izquierda (DAVI) está incrementando en pacientes con insuficiencia cardiaca avanzada. Sin embargo, las infecciones relacionadas al dispositivo representan un reto diagnóstico y de tratamiento, con una importante tasa de morbilidad y mortalidad. El papel de los estudios de imagen de medicina nuclear en las infecciones de DAVI no se ha establecido claramente. El presente estudio comparó la precisión de la tomografía por emisión de positrones/tomografía computada con ^18F-fluorodesoxiglucosa (^18F-FDG PET/CT) y la gammagrafía con leucocitos marcados para el diagnóstico de infecciones en pacientes utilizando un DAVI de flujo continuo. Métodos Desde una base de datos obtenida de manera prospectiva, analizamos de manera retrospectiva el rendimiento diagnóstico de la gammagrafía de leucocitos marcados y del ^18F-FDG PET/CT en 24 pacientes quienes tenían un DAVI con sospecha de infección relacionada al dispositivo. Ambos estudios fueron realizados rutinariamente en todos los pacientes. Se determinó la presencia de infección mediante los criterios de la ISHTL. Resultados Se incluyeron veinticuatro pacientes, de los cuales 15 tuvieron una infección específica de DAV (5 con infecciones DAVI, y 10 con infección del driveline), 6 tuvieron una infección relacionada al DAV, y 3 pacientes tuvieron una infección no relacionada al DAV. La sensibilidad, especificidad, valor predictivo positivo, valor predictivo negativo y precisión diagnóstica fueron 95.2%, 66.7%, 95.2%, 66.7% y 91.6%, respectivamente para ^18F-FDG PET/CT, y 71.4%, 100%, 100%, 33.3% y 75%, respectivamente para la gammagrafía de leucocitos marcados. El ^18F-FDG PET/CT mostró una significativa mayor sensibilidad (p=0.01) que la gammagrafía con leucocitos marcados. Conclusión El ^18F-FDG PET/CT y la gammagrafía de leucocitos marcados tienen un alto desempeño en el diagnóstico de infecciones de DAVI. El ^18F-FDG PET/CT muestra una significativa mayor sensibilidad y podría ser propuesto como el procedimiento de medicina nuclear de primera línea.
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Infections in patients using ventricular-assist devices: Comparison of the diagnostic performance of 18 F-FDG PET/CT scan and leucocyte-labeled scintigraphy
Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology, 2018Co-Authors: Carole Vaugelade, Charles Mesguich, Karine Nubret, Fabrice Camou, Carine Greib, Gael Dournes, Frédéric Debordeaux, Elif Hindie, Laurent Barandon, Ghoufrane TliliAbstract:Background The usage of left-ventricular-assist device (LVAD) is increasing in patients presenting with advanced heart failure. However, device-related infections are a challenge to recognize and to treat, with an important morbidity and mortality rate. The role of nuclear medicine imaging remains not well established for LVAD infections. The present study compared the accuracy of positron emission tomography/computed tomography with 18F-Fludeoxyglucose (18F-FDG PET/CT) and radiolabeled leucocyte scintigraphy for the diagnosis of infections in patients supported with a continuous-flow LVAD.
Koji Sagiyama - One of the best experts on this subject based on the ideXlab platform.
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comparison of positron emission tomography diffusion weighted imaging pet dwi registration quality in a pet mr scanner zoomed dwi vs conventional dwi
Journal of Magnetic Resonance Imaging, 2016Co-Authors: Koji Sagiyama, Yuji Watanabe, Ryotaro Kamei, Shingo Baba, Hiroshi HondaAbstract:Purpose To compare zoomed diffusion-weighted imaging (z-DWI) with reduced field of view (FOV) by spatially selective radiofrequency pulses and conventional echo planar imaging (EPI) DWI (c-DWI) with regard to registration quality using positron emission tomography / magnetic resonance (PET/MR) in patients with malignant tumors. Materials and Methods Fludeoxyglucose (18F) PET imaging, c-DWI, and z-DWI were conducted simultaneously in 21 patients with known or suspected malignancy using a PET/MR system. A fusion image showing the largest tumor area was generated for analysis. Registration accuracy between PET and DWI was assessed based on the area of maximum overlap and central point displacement of the tumor. EPI factor, echo time (TE), matching area, and displacement were compared between c-DWI and z-DWI by paired t-test. Agreement of apparent diffusion coefficient (ADC) acquired by the two sequences were also assessed with linear regression s and Bland–Altman plot analysis. Results Thirty-two lesions were detected on both PET and DWI (mean size 536.3 ± 471.8 mm2). At least one lesion was found in all subjects. In all cases, EPI factor was smaller with z-DWI than c-DWI (43.1 ± 15.6 vs. 62.0 ± 10.0, P < 0.0001), and TE was also shorter for z-DWI (53.6 ± 3.6 msec vs. 65.2 ± 3.6 msec, P < 0.0001). Registration accuracy was better with z-DWI in 30 of 32 lesions (93.8%), and both average matching area and central point displacement were significantly improved (79.8 ± 18.1% vs. 61.8 ± 22.9%, P < 0.0001 and 3.92 ± 2.69 mm vs. 7.51 ± 4.07 mm, P < 0.0001). ADC values calculated with c-DWI and z-DWI showed good agreement. Conclusion Zoomed DWI reduces image distortion and provides better registration accuracy with PET images. J. Magn. Reson. Imaging 2015.
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Comparison of positron emission tomography diffusion-weighted imaging (PET/DWI) registration quality in a PET/MR scanner: Zoomed DWI vs. Conventional DWI.
Journal of magnetic resonance imaging : JMRI, 2015Co-Authors: Koji Sagiyama, Yuji Watanabe, Ryotaro Kamei, Shingo Baba, Hiroshi HondaAbstract:Purpose To compare zoomed diffusion-weighted imaging (z-DWI) with reduced field of view (FOV) by spatially selective radiofrequency pulses and conventional echo planar imaging (EPI) DWI (c-DWI) with regard to registration quality using positron emission tomography / magnetic resonance (PET/MR) in patients with malignant tumors. Materials and Methods Fludeoxyglucose (18F) PET imaging, c-DWI, and z-DWI were conducted simultaneously in 21 patients with known or suspected malignancy using a PET/MR system. A fusion image showing the largest tumor area was generated for analysis. Registration accuracy between PET and DWI was assessed based on the area of maximum overlap and central point displacement of the tumor. EPI factor, echo time (TE), matching area, and displacement were compared between c-DWI and z-DWI by paired t-test. Agreement of apparent diffusion coefficient (ADC) acquired by the two sequences were also assessed with linear regression s and Bland–Altman plot analysis. Results Thirty-two lesions were detected on both PET and DWI (mean size 536.3 ± 471.8 mm2). At least one lesion was found in all subjects. In all cases, EPI factor was smaller with z-DWI than c-DWI (43.1 ± 15.6 vs. 62.0 ± 10.0, P < 0.0001), and TE was also shorter for z-DWI (53.6 ± 3.6 msec vs. 65.2 ± 3.6 msec, P < 0.0001). Registration accuracy was better with z-DWI in 30 of 32 lesions (93.8%), and both average matching area and central point displacement were significantly improved (79.8 ± 18.1% vs. 61.8 ± 22.9%, P < 0.0001 and 3.92 ± 2.69 mm vs. 7.51 ± 4.07 mm, P < 0.0001). ADC values calculated with c-DWI and z-DWI showed good agreement. Conclusion Zoomed DWI reduces image distortion and provides better registration accuracy with PET images. J. Magn. Reson. Imaging 2015.