Hybrid FDG-PET/MR compared to FDG-PET/CT in adult lymphoma patients.

Science.gov (United States)

Atkinson, Wendy; Catana, Ciprian; Abramson, Jeremy S; Arabasz, Grae; McDermott, Shanaugh; Catalano, Onofrio; Muse, Victorine; Blake, Michael A; Barnes, Jeffrey; Shelly, Martin; Hochberg, Ephraim; Rosen, Bruce R; Guimaraes, Alexander R

2016-07-01

The goal of this study is to evaluate the diagnostic performance of simultaneous FDG-PET/MR including diffusion compared to FDG-PET/CT in patients with lymphoma. Eighteen patients with a confirmed diagnosis of non-Hodgkin's (NHL) or Hodgkin's lymphoma (HL) underwent an IRB-approved, single-injection/dual-imaging protocol consisting of a clinical FDG-PET/CT and subsequent FDG-PET/MR scan. PET images from both modalities were reconstructed iteratively. Attenuation correction was performed using low-dose CT data for PET/CT and Dixon-MR sequences for PET/MR. Diffusion-weighted imaging was performed. SUVmax was measured and compared between modalities and the apparent diffusion coefficient (ADC) using ROI analysis by an experienced radiologist using OsiriX. Strength of correlation between variables was measured using the Pearson correlation coefficient (r p). Of the 18 patients included in this study, 5 had HL and 13 had NHL. The median age was 51 ± 14.8 years. Sixty-five FDG-avid lesions were identified. All FDG-avid lesions were visible with comparable contrast, and therefore initial and follow-up staging was identical between both examinations. SUVmax from FDG-PET/MR [(mean ± sem) (21.3 ± 2.07)] vs. FDG-PET/CT (mean 23.2 ± 2.8) demonstrated a strongly positive correlation [r s = 0.95 (0.94, 0.99); p < 0.0001]. There was no correlation found between ADCmin and SUVmax from FDG-PET/MR [r = 0.17(-0.07, 0.66); p = 0.09]. FDG-PET/MR offers an equivalent whole-body staging examination as compared with PET/CT with an improved radiation safety profile in lymphoma patients. Correlation of ADC to SUVmax was weak, understating their lack of equivalence, but not undermining their potential synergy and differing importance.

94th German Roentgen congress. Program and abstracts

International Nuclear Information System (INIS)

2013-01-01

The volume includes the abstracts of the 94th German Roentgen congress concerning the following topics: Interventional oncology; mammary carcinoma; medical care and imaging; news in radio-oncology; regional therapy of lung malign tumors; medical ontology intelligent searching strategy; image fusion; oncology - imaging in screening; cardiovascular emergency - an update; innovations in the physics of radiology; risk management and budget; mobile computing; mammary diagnostics; elucidation and liability benchmarking in radiology; cost and performance in the medical office; research: innovation or self-purpose; cost refunding PET/CT and MRT PET; economic strategy in health care; options of radiological practice in medical offices and hospitals; trends in imaging; radiological diagnostics in emergency cases; X-ray regulations; neuroradiology; muscuskeletal radiology; chest radiology; pediatric radiology, radiation protection for the medical personnel.

78 FR 73112 - Boundary Expansion of Thunder Bay National Marine Sanctuary

Science.gov (United States)

2013-12-05

.... 130403324-3376-01] RIN 0648-BC94 Boundary Expansion of Thunder Bay National Marine Sanctuary AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric... boundary of the Thunder Bay National Marine Sanctuary. This document re-opens the public comment period...

78 FR 49700 - Boundary Expansion of Thunder Bay National Marine Sanctuary

Science.gov (United States)

2013-08-15

.... 130403324-3376-01] RIN 0648-BC94 Boundary Expansion of Thunder Bay National Marine Sanctuary AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric... boundary of the Thunder Bay National Marine Sanctuary (78 FR 35776). This notice reopens the public comment...

Application of PET in breast cancer

International Nuclear Information System (INIS)

Noh, Dong Young

2002-01-01

Positron emission tomography (PET) is an imaging method that employs radionuclide and tomography techniques. Since 1995, we applied PET not only to the diagnosis of breast cancer but also to the detection of abnormalities in the augmented breast and to the detection of metastasis. Until 2001, we evaluated 242 breast cases by PET at PET center of Seoul National University Hospital. Our group has reported serially at the international journals. In the firtst report, PET showed high sensitivity for detecting breast cancer, both the primary and axillary node metastasis. A total of 27 patients underwent breast operations based on PET results at Seoul National University Hospital from 1995 to 1996. The diagnostic accuracy of PET were 97% for the primary tumor mass and 96% for axillary lymph node metastasis. In case of the breast augmented, PET also showed excellent diagnostic results for primary breast cancer and axillary lymph node metastasis where mammography and ultrasound could not diagnose properly. PET also had outstanding results in the detection of recurrent or metastatic breast cancer(sensitivity 94%, specificity 80%, accuracy 89%). In addition, our study gave some evidence that PET could be applied further to evaluate the growth rate of tumors by measuring SUV, and finally to prognosticated the disease. PET could also be applied to evaluate the response after chemotherapy to measure its metabolic rate and size. In conclsion, PET is a highly sensitive, accurate diagnostic tool for breast cancer of primary lesion in various conditions including metastasis

FDG-PET and FDG-PET/CT for therapy monitoring and restaging in malignant lymphoma

International Nuclear Information System (INIS)

Mottaghy, F.M.; Krause, B.J.

2003-01-01

F-18-fluorodeoxyglucose (FDG) PET allows to assess residual masses in patients with malignant lymphoma differentiating vital tumor from scar tissue. This approach is not applicable with conventional imaging methods (CDM) such as CT or MRI. On the other hand circumscribed results often cannot be definitely allocated in PET, therefore the combined morphological-biochemical approach using the now available PET/CT systems promises to be a pathbreaking technical progress. There is no doubt that stand alone PET is superior to CDM differentiating residual scar tissue from vital tumor as has been shown in 15 recently published studies. The median sensitivity for detecting active disease with FDG PET across the studies was 91%; the corresponding specificity was 89%. As a result FDG PET had a high negative predictive value of 94%. In contrast, specificity and positive predictive value (PPV) of CDM in the 9 studies were a direct comparison was available were low (31% and 46%, one study 82%). PET positive residual masses were associated with a progression-free survival of 0 - 55%. Only a few studies have included FDG-PET in therapy response monitoring studies, however also these results are promising. At the moment FDG-PET seems to be the best possibility to characterize and qualitatively visualize vitality of tumor masses and also hold promises for efficient therapy response monitoring in patients with malignant lymphoma. Therefore it should be included in standard diagnostic protocols in lymphoma patients. The combined PET/CT has to be ranked superior to conventional PET studies as in many cases the combined structural and functional imaging brings a clearer diagnostic statement. (orig.) [de

78 FR 64186 - Boundary Expansion of Thunder Bay National Marine Sanctuary

Science.gov (United States)

2013-10-28

.... 130403324-3 376-01 RIN 0648-BC94] Boundary Expansion of Thunder Bay National Marine Sanctuary AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric... boundary of the Thunder Bay National Marine Sanctuary (78 FR 35776). On August 15, NOAA re-opened the...

Nuclear factor κB inhibitor BAY 11-7082 suppresses oxidative stress induced by endothelin-1 (ET-1) in rat kidney.

Science.gov (United States)

Kowalczyk, Agata; Kołodziejczyk, Michał; Gorąca, Anna

2015-12-31

The aim of the study was to evaluate the effect of BAY 11-7082, an NF-κB inhibitor, on basal and ET-1-induced production of reactive oxygen species (ROS), TNF-α and p65 protein in rat kidney. The experimental animals were divided into five groups (n=7) receiving: 1) saline (control); 2 and 3) ET-1 in a dose of 3 μg/kg body weight (b.w.) or 12.5 μg/kg b.w.; 4) BAY 11-7082 (10 mg/kg b.w.); 5) BAY 11-7082 (10 mg/kg b.w.) and ET-1 (12.5 μg/kg b.w.), respectively. In kidney homogenates the concentration of thiobarbituric acid reactive substances (TBARS), H2O2, TNF-α, p65 protein and GSH/GSSG ratio were determined. ET-1 resulted in a dose-dependent increase in TBARS and hydrogen peroxide (H2O2) levels, and a decrease in GSH/GSSG ratio when compared to the controls. BAY 11-7082 administered 1 h before ET-1 administration at a dose of 12.5 μg/kg resulted in a decrease (PET-1 groups. The level of TNF-α was increased (PET-1, while BAY 11-7082 reduced the TNF-α level (PET-1 induced oxidative stress in kidney tissue. These actions of BAY 11-7082 may result from reduced activity of NF-κB signaling pathways. Inhibition of the NF-κB pathway may be a promising strategy for preventing the progression of kidney damage.

Diagnostic accuracy of FDG PET/CT in mediastinal lymph nodal staging of the non-small cell lung cancer: prospective study with PET/CT of 182 cases

International Nuclear Information System (INIS)

Lee, J. W.; Kang, W. J.; Kim, B. S.; Lee, D. S.; Jeong, J. K.; Lee, M. C.

2007-01-01

This study was performed to assess the accuracy of fluorodeoxyglucose - positron emission tomography/computed tomography (FDG-PET/CT) in the mediastinal lymph nodal staging of non-small cell lung cancer as compared with CT. Between March 2004 and February 2006, 182 patients (126 men and 56 women; mean age, 60.7 y) with non-small cell lung cancer underwent FDG PET/CT and enhanced chest CT. PET/CT and CT images were acquired in a prospective manner. These images were evaluated separately by 2 different physicians and nodal stages were determined by using American Joint Committee on Cancer staging systems. The maxSUV, location, size, calcification and pattern of FDG uptake of lymph nodes were considered. Surgical and histological findings served as the reference standard. A total of 182 patients with 778 mediastinal nodal stations were evaluated. Among them, metastases were found in 36 patients with 53 nodal stations. The respective values for sensitivity, specificity, positive predictive value, negative predictive value and accuracy of mediastinal lymph node staging were 36%, 80%, 30%, 84% and 71% with CT and 75%, 89%, 63%, 94% and 86% with PET/CT on per-patient basis, and 23%, 92%, 18%, 94% and 88% with CT and 66%, 96%, 54%, 98% and 94% with PET/CT on per-nodal-station basis. The maxSUVs of metastatic lymph nodes were significantly higher than those of benign nodes (p = 0.0008). Seventy seven percent (27/35) of the metastatic lymph nodes on FDG-PET/CT images were less than a 1cm in the short axis. Moreover, some benign lymph node patterns, such as bilateral symmetric nodes with similar FDG uptake, benign pattern of nodal calcification and small-sized lymph node with much higher maxSUV than primary tumor, were noted during the evaluation of FDG-PET/CT images. This prospective study suggests that FDG-PET/CT is more accurately stage the mediastinal lymph node staging than CT, and that it provides high specificity and a negative predictive value

Role of FDG-PET/MRI, FDG-PET/CT, and Dynamic Susceptibility Contrast Perfusion MRI in Differentiating Radiation Necrosis from Tumor Recurrence in Glioblastomas.

Science.gov (United States)

Hojjati, Mojgan; Badve, Chaitra; Garg, Vasant; Tatsuoka, Curtis; Rogers, Lisa; Sloan, Andrew; Faulhaber, Peter; Ros, Pablo R; Wolansky, Leo J

2018-01-01

To compare the utility of quantitative PET/MRI, dynamic susceptibility contrast (DSC) perfusion MRI (pMRI), and PET/CT in differentiating radiation necrosis (RN) from tumor recurrence (TR) in patients with treated glioblastoma multiforme (GBM). The study included 24 patients with GBM treated with surgery, radiotherapy, and temozolomide who presented with progression on imaging follow-up. All patients underwent PET/MRI and pMRI during a single examination. Additionally, 19 of 24 patients underwent PET/CT on the same day. Diagnosis was established by pathology in 17 of 24 and by clinical/radiologic consensus in 7 of 24. For the quantitative PET/MRI and PET/CT analysis, a region of interest (ROI) was drawn around each lesion and within the contralateral white matter. Lesion to contralateral white matter ratios for relative maximum, mean, and median were calculated. For pMRI, lesion ROI was drawn on the cerebral blood volume (CBV) maps and histogram metrics were calculated. Diagnostic performance for each metric was assessed using receiver operating characteristic curve analysis and area under curve (AUC) was calculated. In 24 patients, 28 lesions were identified. For PET/MRI, relative mean ≥ 1.31 resulted in AUC of .94 with both sensitivity and negative predictive values (NPVs) of 100%. For pMRI, CBV max ≥3.32 yielded an AUC of .94 with both sensitivity and NPV measuring 100%. The joint model utilizing r-mean (PET/MRI) and CBV mode (pMRI) resulted in AUC of 1.0. Our study demonstrates that quantitative PET/MRI parameters in combination with DSC pMRI provide the best diagnostic utility in distinguishing RN from TR in treated GBMs. © 2017 The Authors. Journal of Neuroimaging published by Wiley Periodicals, Inc. on behalf of American Society of Neuroimaging.

18F-FDG PET of the hands with a dedicated high-resolution PEM system (arthro-PET): correlation with PET/CT, radiography and clinical parameters.

Science.gov (United States)

Mhlanga, Joyce C; Carrino, John A; Lodge, Martin; Wang, Hao; Wahl, Richard L

2014-12-01

The aim of this study was to prospectively determine the feasibility and compare the novel use of a positron emission mammography (PEM) scanner with standard PET/CT for evaluating hand osteoarthritis (OA) with (18)F-FDG. Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study in which 14 adults referred for oncological (18)F-FDG PET/CT underwent dedicated hand PET/CT followed by arthro-PET using the PEM device. Hand radiographs were obtained and scored for the presence and severity of OA. Summed qualitative and quantitative joint glycolytic scores for each modality were compared with the findings on plain radiography and clinical features. Eight patients with clinical and/or radiographic evidence of OA comprised the OA group (mean age 73 ± 7.7 years). Six patients served as the control group (53.7 ± 9.3 years). Arthro-PET quantitative and qualitative joint glycolytic scores were highly correlated with PET/CT findings in the OA patients (r = 0.86. p = 0.007; r = 0.94, p = 0.001). Qualitative arthro-PET and PET/CT joint scores were significantly higher in the OA patients than in controls (38.7 ± 6.6 vs. 32.2 ± 0.4, p = 0.02; 37.5 ± 5.4 vs. 32.2 ± 0.4, p = 0.03, respectively). Quantitative arthro-PET and PET/CT maximum SUV-lean joint scores were higher in the OA patients, although they did not reach statistical significance (20.8 ± 4.2 vs. 18 ± 1.8, p = 0.13; 22.8 ± 5.38 vs. 20.1 ± 1.54, p = 0.21). By definition, OA patients had higher radiographic joint scores than controls (30.9 ± 31.3 vs. 0, p = 0.03). Hand imaging using a small field of view PEM system (arthro-PET) with FDG is feasible, performing comparably to PET/CT in assessing metabolic joint activity. Arthro-PET and PET/CT showed higher joint FDG uptake in OA. Further exploration of arthro-PET in arthritis management is warranted.

Role of FDG-PET in the Diagnosis of Recurrence and Assessment of Therapeutic Response in Cervical Cancer and Ovarian Cancer Patients: Comparison of Diagnostic Report between PET, Abdominal CT and Tumor Marker

International Nuclear Information System (INIS)

Han, You Mie; Choe, Jae Gol; Kang, Bung Chul

2008-01-01

We aimed to assess the role of positron emission tomography using fluorodeoxyglucose (FDG-PET) in the diagnosis of recurrence or the assessment of therapeutic response in cervical and ovarian cancer patients through making a comparison between FDG-PET, abdominal computed tomography (CT) and serum tumor marker. We included 103 cases (67 patients) performed FDG-PET and abdominal CT. There were 42 cervical cancers and 61 ovarian cancers. We retrospectively reviewed the interpretations of PET and CT images as well as the level of tumor marker. We calculated their sensitivity, specificity, positive predictive value and negative predictive value for these three modalities. And then we analyzed the differences between these three modalities. Tumor recurrences were diagnosed in 37 cases (11 cervical cancers and 26 ovarian cancers). For PET, CT and tumor marker, in cervical cancer group, sensitivity was 100% (11/11), 54.5% (6/11) and 81.1% (9/11), respectively. And specificity was 93.6% (29/31), 93.6% (29/31) and 100% (31/31). In ovarian cancer group, sensitivity was 96.2% (25/26), 84.6% (22/26) and 80.8% (21/26), and specificity was 94.3% (33/35), 94.3% (33/35), 94.3% (33/35). PET was highly sensitive to detect the intraperitoneal and extraperitoneal metastasis with the help of the CT images to localize the lesions. However, CT had limitations in differentiation of the recurrent tumor from benign fibrotic tissue, identification of viable tumors at the interface of tissues, and detecting extraperitoneal lesions. FDG-PET can be an essential modality to detect the recurrent or residual tumors in gynecologic cancer patients because of its great field of the application and high sensitivity

18F-FDG PET of the hands with a dedicated high-resolution PEM system (arthro-PET): correlation with PET/CT, radiography and clinical parameters

International Nuclear Information System (INIS)

Mhlanga, Joyce C.; Lodge, Martin; Carrino, John A.; Wang, Hao; Wahl, Richard L.

2014-01-01

The aim of this study was to prospectively determine the feasibility and compare the novel use of a positron emission mammography (PEM) scanner with standard PET/CT for evaluating hand osteoarthritis (OA) with 18 F-FDG. Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study in which 14 adults referred for oncological 18 F-FDG PET/CT underwent dedicated hand PET/CT followed by arthro-PET using the PEM device. Hand radiographs were obtained and scored for the presence and severity of OA. Summed qualitative and quantitative joint glycolytic scores for each modality were compared with the findings on plain radiography and clinical features. Eight patients with clinical and/or radiographic evidence of OA comprised the OA group (mean age 73 ± 7.7 years). Six patients served as the control group (53.7 ± 9.3 years). Arthro-PET quantitative and qualitative joint glycolytic scores were highly correlated with PET/CT findings in the OA patients (r = 0.86. p = 0.007; r = 0.94, p = 0.001). Qualitative arthro-PET and PET/CT joint scores were significantly higher in the OA patients than in controls (38.7 ± 6.6 vs. 32.2 ± 0.4, p = 0.02; 37.5 ± 5.4 vs. 32.2 ± 0.4, p = 0.03, respectively). Quantitative arthro-PET and PET/CT maximum SUV-lean joint scores were higher in the OA patients, although they did not reach statistical significance (20.8 ± 4.2 vs. 18 ± 1.8, p = 0.13; 22.8 ± 5.38 vs. 20.1 ± 1.54, p= 0.21). By definition, OA patients had higher radiographic joint scores than controls (30.9 ± 31.3 vs. 0, p = 0.03). Hand imaging using a small field of view PEM system (arthro-PET) with FDG is feasible, performing comparably to PET/CT in assessing metabolic joint activity. Arthro-PET and PET/CT showed higher joint FDG uptake in OA. Further exploration of arthro-PET in arthritis management is warranted. (orig.)

Clinical utility of flumazenil-PET versus [18F]fluorodeoxyglucose-PET and MRI in refractory partial epilepsy. A prospective study in 100 patients.

Science.gov (United States)

Ryvlin, P; Bouvard, S; Le Bars, D; De Lamérie, G; Grégoire, M C; Kahane, P; Froment, J C; Mauguière, F

1998-11-01

We assessed the clinical utility of [11C]flumazenil-PET (FMZ-PET) prospectively in 100 epileptic patients undergoing a pre-surgical evaluation, and defined the specific contribution of this neuro-imaging technique with respect to those of MRI and [18F]fluorodeoxyglucose-PET (FDG-PET). All patients benefited from a long term video-EEG monitoring, whereas an intracranial EEG investigation was performed in 40 cases. Most of our patients (73%) demonstrated a FMZ-PET abnormality; this hit rate was significantly higher in temporal lobe epilepsy (94%) than in other types of epilepsy (50%) (P lobe epilepsy associated with MRI signs of hippocampal sclerosis, FMZ-PET abnormalities delineated the site of seizure onset precisely, whenever they were coextensive with FDG-PET abnormalities; (ii) in bi-temporal epilepsy, FMZ-PET helped to confirm the bilateral origin of seizures by showing a specific pattern of decreased FMZ binding in both temporal lobes in 33% of cases; (iii) in patients with a unilateral cryptogenic frontal lobe epilepsy, FMZ-PET provided further evidence of the side and site of seizure onset in 55% of cases. Thus, FMZ-PET deserves to be included in the pre-surgical evaluation of these specific categories of epileptic patients, representing approximately half of the population considered for epilepsy surgery.

Quantitative Evaluation of Atlas-based Attenuation Correction for Brain PET in an Integrated Time-of-Flight PET/MR Imaging System.

Science.gov (United States)

Yang, Jaewon; Jian, Yiqiang; Jenkins, Nathaniel; Behr, Spencer C; Hope, Thomas A; Larson, Peder E Z; Vigneron, Daniel; Seo, Youngho

2017-07-01

Purpose To assess the patient-dependent accuracy of atlas-based attenuation correction (ATAC) for brain positron emission tomography (PET) in an integrated time-of-flight (TOF) PET/magnetic resonance (MR) imaging system. Materials and Methods Thirty recruited patients provided informed consent in this institutional review board-approved study. All patients underwent whole-body fluorodeoxyglucose PET/computed tomography (CT) followed by TOF PET/MR imaging. With use of TOF PET data, PET images were reconstructed with four different attenuation correction (AC) methods: PET with patient CT-based AC (CTAC), PET with ATAC (air and bone from an atlas), PET with ATAC patientBone (air and tissue from the atlas with patient bone), and PET with ATAC boneless (air and tissue from the atlas without bone). For quantitative evaluation, PET mean activity concentration values were measured in 14 1-mL volumes of interest (VOIs) distributed throughout the brain and statistical significance was tested with a paired t test. Results The mean overall difference (±standard deviation) of PET with ATAC compared with PET with CTAC was -0.69 kBq/mL ± 0.60 (-4.0% ± 3.2) (P PET with ATAC boneless (-9.4% ± 3.7) was significantly worse than that of PET with ATAC (-4.0% ± 3.2) (P PET with ATAC patientBone (-1.5% ± 1.5) improved over that of PET with ATAC (-4.0% ± 3.2) (P PET/MR imaging achieves similar quantification accuracy to that from CTAC by means of atlas-based bone compensation. However, patient-specific anatomic differences from the atlas causes bone attenuation differences and misclassified sinuses, which result in patient-dependent performance variation of ATAC. © RSNA, 2017 Online supplemental material is available for this article.

{sup 18}F-FDG PET of the hands with a dedicated high-resolution PEM system (arthro-PET): correlation with PET/CT, radiography and clinical parameters

Energy Technology Data Exchange (ETDEWEB)

Mhlanga, Joyce C.; Lodge, Martin [Johns Hopkins University School of Medicine, Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, MD (United States); Carrino, John A. [Johns Hopkins University School of Medicine, Division of Musculoskeletal Radiology, The Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, MD (United States); Wang, Hao [Johns Hopkins University School of Medicine, Department of Oncology Biostatistics Division, Baltimore, MD (United States); Wahl, Richard L. [Johns Hopkins University School of Medicine, Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Sciences, Baltimore, MD (United States); Johns Hopkins University Hospitals, Division of Nuclear Medicine, Baltimore, MD (United States)

2014-12-15

The aim of this study was to prospectively determine the feasibility and compare the novel use of a positron emission mammography (PEM) scanner with standard PET/CT for evaluating hand osteoarthritis (OA) with {sup 18}F-FDG. Institutional review board approval and written informed consent were obtained for this HIPAA-compliant prospective study in which 14 adults referred for oncological {sup 18}F-FDG PET/CT underwent dedicated hand PET/CT followed by arthro-PET using the PEM device. Hand radiographs were obtained and scored for the presence and severity of OA. Summed qualitative and quantitative joint glycolytic scores for each modality were compared with the findings on plain radiography and clinical features. Eight patients with clinical and/or radiographic evidence of OA comprised the OA group (mean age 73 ± 7.7 years). Six patients served as the control group (53.7 ± 9.3 years). Arthro-PET quantitative and qualitative joint glycolytic scores were highly correlated with PET/CT findings in the OA patients (r = 0.86. p = 0.007; r = 0.94, p = 0.001). Qualitative arthro-PET and PET/CT joint scores were significantly higher in the OA patients than in controls (38.7 ± 6.6 vs. 32.2 ± 0.4, p = 0.02; 37.5 ± 5.4 vs. 32.2 ± 0.4, p = 0.03, respectively). Quantitative arthro-PET and PET/CT maximum SUV-lean joint scores were higher in the OA patients, although they did not reach statistical significance (20.8 ± 4.2 vs. 18 ± 1.8, p = 0.13; 22.8 ± 5.38 vs. 20.1 ± 1.54, p= 0.21). By definition, OA patients had higher radiographic joint scores than controls (30.9 ± 31.3 vs. 0, p = 0.03). Hand imaging using a small field of view PEM system (arthro-PET) with FDG is feasible, performing comparably to PET/CT in assessing metabolic joint activity. Arthro-PET and PET/CT showed higher joint FDG uptake in OA. Further exploration of arthro-PET in arthritis management is warranted. (orig.)

94th German Roentgen congress. Program and abstracts; 94. Deutscher Roentgenkongress ''Radiologie ist Zukunft''. Vollstaendiges Kongressprogramm und Abstracts der wissenschaftlichen Beitraege

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-05-15

The volume includes the abstracts of the 94th German Roentgen congress concerning the following topics: Interventional oncology; mammary carcinoma; medical care and imaging; news in radio-oncology; regional therapy of lung malign tumors; medical ontology intelligent searching strategy; image fusion; oncology - imaging in screening; cardiovascular emergency - an update; innovations in the physics of radiology; risk management and budget; mobile computing; mammary diagnostics; elucidation and liability benchmarking in radiology; cost and performance in the medical office; research: innovation or self-purpose; cost refunding PET/CT and MRT PET; economic strategy in health care; options of radiological practice in medical offices and hospitals; trends in imaging; radiological diagnostics in emergency cases; X-ray regulations; neuroradiology; muscuskeletal radiology; chest radiology; pediatric radiology, radiation protection for the medical personnel.

Side-by-side reading of PET and CT scans in oncology: Which patients might profit from integrated PET/CT?

International Nuclear Information System (INIS)

Reinartz, Patrick; Wieres, Franz-Josef; Schneider, Wolfram; Schur, Alexander; Buell, Ulrich

2004-01-01

Most early publications on integrated positron emission tomography/computed tomography (PET/CT) devices have reported the new scanner generation to be superior to conventional PET. However, few of these studies have analysed the situation where, in addition to PET, a current CT scan is available for side-by-side viewing. This fact is important, because combined PET/CT or a software-based fusion of the two modalities may improve diagnosis only in cases where side-by-side reading of PET and CT data does not lead to a definitive diagnosis. The aim of this study was to analyse which patients will profit from integrated PET/CT in terms of lesion characterization. A total of 328 consecutively admitted patients referred for PET in whom a current CT scan was available were included in the study. The localization of all pathological PET lesions, as well as possible infiltration of adjacent anatomical structures, was assessed. Of 467 pathological lesions, 94.0% were correctly assessed with respect to localization and infiltration by either conventional PET alone (51.6%) or combined reading of PET and the already existing CT scans (42.4%). Hence, in only 6.0% of all lesions, affecting 6.7% of all patients, could evaluation have profited from integrated PET/CT. We conclude that side-by-side viewing of PET and CT scans is essential, as in 42.4% of all cases, combined viewing was important for a correct diagnosis in our series. In up to 6.7% of patients, integrated PET/CT might have given additional information, so that in nearly 50% of patients some form of combined viewing of PET and CT data is needed for accurate lesion characterization. (orig.)

Positron Emission Tomography (PET) Evaluation After Initial Chemotherapy and Radiation Therapy Predicts Local Control in Rhabdomyosarcoma

Energy Technology Data Exchange (ETDEWEB)

Dharmarajan, Kavita V., E-mail: dharmark@mskcc.org [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States); Wexler, Leonard H.; Gavane, Somali; Fox, Josef J.; Schoder, Heiko; Tom, Ashlyn K.; Price, Alison N.; Meyers, Paul A.; Wolden, Suzanne L. [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States)

2012-11-15

Purpose: 18-fluorodeoxyglucose positron emission tomography (PET) is already an integral part of staging in rhabdomyosarcoma. We investigated whether primary-site treatment response characterized by serial PET imaging at specific time points can be correlated with local control. Patients and Methods: We retrospectively examined 94 patients with rhabdomyosarcoma who received initial chemotherapy 15 weeks (median) before radiotherapy and underwent baseline, preradiation, and postradiation PET. Baseline PET standardized uptake values (SUVmax) and the presence or absence of abnormal uptake (termed PET-positive or PET-negative) both before and after radiation were examined for the primary site. Local relapse-free survival (LRFS) was calculated according to baseline SUVmax, PET-positive status, and PET-negative status by the Kaplan-Meier method, and comparisons were tested with the log-rank test. Results: The median patient age was 11 years. With 3-year median follow-up, LRFS was improved among postradiation PET-negative vs PET-positive patients: 94% vs 75%, P=.02. By contrast, on baseline PET, LRFS was not significantly different for primary-site SUVmax {<=}7 vs >7 (median), although the findings suggested a trend toward improved LRFS: 96% for SUVmax {<=}7 vs 79% for SUVmax >7, P=.08. Preradiation PET also suggested a statistically insignificant trend toward improved LRFS for PET-negative (97%) vs PET-positive (81%) patients (P=.06). Conclusion: Negative postradiation PET predicted improved LRFS. Notably, 77% of patients with persistent postradiation uptake did not experience local failure, suggesting that these patients could be closely followed up rather than immediately referred for intervention. Negative baseline and preradiation PET findings suggested statistically insignificant trends toward improved LRFS. Additional study may further understanding of relationships between PET findings at these time points and outcome in rhabdomyosarcoma.

Usefulness of FDG PET/CT in determining benign from malignant endobronchial obstruction

International Nuclear Information System (INIS)

Cho, Arthur; Kang, Won Jun; Cho, Ho Jin; Lee, Jae-hoon; Yun, Mijin; Lee, Jong Doo; Hur, Jin

2011-01-01

To evaluate the usefulness of FDG PET/CT to differentiate malignant endobronchial lesions with distal atelectasis from benign bronchial stenosis. This retrospective study reviewed 84 patients who underwent contrast-enhanced chest CT and then PET/CT and had histological (n = 81) or follow-up imaging (n = 3) confirmation. Two chest radiologists reviewed initial chest CT and determined endobronchial lesions to be malignant or benign. Two nuclear medicine physicians reviewed PET/CT for FDG uptake at the obstruction site and measured SUV. Malignancy was considered when increased FDG uptake was seen in the obstruction site, regardless of FDG within the atelectatic lung. The sensitivity, specificity and accuracy of chest CT was 95%, 48% and 84%, compared with 95%, 91% and 94% for PET/CT. Benign obstructive lesions showed statistically lower FDG uptake than malignant obstructions (benign SUV 2.5 ± 0.84; malignant SUV 11.8 ± 5.95, p < 0.001). ROC analysis showed an SUV cut-off value of 3.4 with highest sensitivity of 94% and specificity of 91%. Increased FDG PET/CT uptake at the obstruction site indicates a high probability of malignancy, while benign lesions show low FDG uptake. Careful evaluation of FDG uptake pattern at the obstruction site is helpful in the differentiation between benign and malignant endobronchial lesions. (orig.)

Usefulness of FDG PET/CT in determining benign from malignant endobronchial obstruction

Energy Technology Data Exchange (ETDEWEB)

Cho, Arthur; Kang, Won Jun; Cho, Ho Jin; Lee, Jae-hoon; Yun, Mijin; Lee, Jong Doo [Yonsei University Health System, Division of Nuclear Medicine, Department of Radiology, Seoul (Korea, Republic of); Hur, Jin [Yonsei University Health System, Department of Radiology, Seoul (Korea, Republic of)

2011-05-15

To evaluate the usefulness of FDG PET/CT to differentiate malignant endobronchial lesions with distal atelectasis from benign bronchial stenosis. This retrospective study reviewed 84 patients who underwent contrast-enhanced chest CT and then PET/CT and had histological (n = 81) or follow-up imaging (n = 3) confirmation. Two chest radiologists reviewed initial chest CT and determined endobronchial lesions to be malignant or benign. Two nuclear medicine physicians reviewed PET/CT for FDG uptake at the obstruction site and measured SUV. Malignancy was considered when increased FDG uptake was seen in the obstruction site, regardless of FDG within the atelectatic lung. The sensitivity, specificity and accuracy of chest CT was 95%, 48% and 84%, compared with 95%, 91% and 94% for PET/CT. Benign obstructive lesions showed statistically lower FDG uptake than malignant obstructions (benign SUV 2.5 {+-} 0.84; malignant SUV 11.8 {+-} 5.95, p < 0.001). ROC analysis showed an SUV cut-off value of 3.4 with highest sensitivity of 94% and specificity of 91%. Increased FDG PET/CT uptake at the obstruction site indicates a high probability of malignancy, while benign lesions show low FDG uptake. Careful evaluation of FDG uptake pattern at the obstruction site is helpful in the differentiation between benign and malignant endobronchial lesions. (orig.)

Optimasi Naive Bayes Dengan Pemilihan Fitur Dan Pembobotan Gain Ratio

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I Guna Adi Socrates

2016-03-01

Full Text Available Naïve Bayes merupakan salah satu metode data mining yang umum digunakan dalam klasifikasi dokumen berbasis text. Kelebihan dari metode ini adalah algoritma yang sederhana dengan  kompleksitas  perhitungan  yang  rendah.  Akan  tetapi,  pada  metode  Naïve  Bayes terdapat kelemahan dimana sifat independensi dari fitur Naïve Bayes tidak dapat selalu diterapkan sehingga akan berpengaruh pada tingkat akurasi perhitungan. Maka dari itu, metode Naïve Bayes perlu dioptimasi dengan cara pemberian bobot mengunakan Gain Ratio. Namun, pemberian bobot pada Naïve Bayes menimbulkan permasalahan pada penghitungan probabilitas setiap    dokumen, dimana fitur  yang tidak  merepresentasikan kelas  yang diuji banyak muncul sehingga terjadi kesalahan klasifikasi. Oleh karena itu, pembobotan Naïve Bayes   masih   belum   optimal.   Paper   ini mengusulkan  optimasi  metode   Naïve   Bayes mengunakan pembobotan Gain Ratio yang ditambahkan dengan metode pemilihan fitur pada kasus klasifikasi teks. Hasil penelitian ini menunjukkan bahwa optimasi metode Naïve Bayes menggunakan pemilihan fitur dan pembobotan menghasilkan akurasi sebesar 94%.

Evaluation of 68Ga-DOTATOC PET/MRI for whole-body staging of neuroendocrine tumours in comparison with 68Ga-DOTATOC PET/CT.

Science.gov (United States)

Sawicki, Lino M; Deuschl, Cornelius; Beiderwellen, Karsten; Ruhlmann, Verena; Poeppel, Thorsten D; Heusch, Philipp; Lahner, Harald; Führer, Dagmar; Bockisch, Andreas; Herrmann, Ken; Forsting, Michael; Antoch, Gerald; Umutlu, Lale

2017-10-01

To compare the diagnostic performance of 68 Ga-DOTATOC PET/MRI and 68 Ga-DOTATOC PET/CT in the whole-body staging of patients with neuroendocrine tumours (NET). Thirty patients with histopathologically confirmed NET underwent PET/CT and PET/MRI in a single-injection protocol. PET/CT and PET/MRI scans were prospectively evaluated with regard to lesion count, localization, nature (NET/non-NET), and conspicuity (four-point scale). Histopathology and follow-up imaging served as the reference standards. The proportions of NET and non-NET lesions rated correctly were compared using McNemar's chi-squared test. The Wilcoxon test was used to assess differences in SUVmax and lesion conspicuity. The correlation between the SUVmax for the same lesions from each modality was analysed using Pearson's correlation coefficient (r). According to the reference standard, there were 197 lesions (142 NET, 55 non-NET). Lesion-based analysis showed a higher proportion of correctly rated NET lesions on PET/MRI than on PET/CT (90.8% vs. 86.7%, p = 0.031), whereas on PET/CT there was a higher proportion of correctly rated non-NET lesions (94.5% vs. 83.6%, p = 0.031). SUVmax was strongly correlated (r = 0.86; p PET/MRI (both p PET/MRI yielded a higher proportion of correctly rated NET lesions and should be regarded as a valuable alternative to 68 Ga-DOTATOC PET/CT in whole-body staging of NET patients. • 68 Ga-DOTATOC PET/MRI correctly identified more NET lesions than 68 Ga-DOTATOC PET/CT. • 68 Ga-DOTATOC PET/MRI provides better NET lesion conspicuity than 68 Ga-DOTATOC PET/CT. • SUVmax values from the two modalities are strongly correlated and do not differ significantly.

Observation on Heavy Metals in Sediment of Jakarta Bay Waters

Directory of Open Access Journals (Sweden)

Abdul Rozak

2007-04-01

Full Text Available Observation on heavy metals in Jakarta Bay, from June and September 2003. Heavy metals Pb in sediment at the West have been conductet of Jakarta Bay Waters varied between Pb = 8,49-31,22 ppm, Cd = <0,001-0,47 ppm, Cu = 13,81-193,75 ppm, Zn = 82,18-533,59 ppm and Ni = 0,99-35,38 ppm,while those at the Center of Jakarta Bay, varied between Pb = 2,21-69,22 ppm, Cd = <0,001-0,28 ppm, Cu = 3,36-50,65 ppm, Zn = 71,13-230,54 ppm and Ni = 0,42-15,58 ppm and at the East of Jakarta Bay, Pb content varied between 0,25-77,42 ppm, Cd = <0,001-0,42 ppm, Cu = 0,79-44,94 ppm, Zn = 93,21-289,00 ppm and Ni = 0,42-128,47 ppm. Hevy metals content in sediment the West of Jakarta Bay was high of equivalent the Center and East of Jakarta Bay. At than those composition sediment at the west was black, that indicated high heavy metals content.

Evaluation of 68Ga-DOTATOC PET/MRI for whole-body staging of neuroendocrine tumours in comparison with 68Ga-DOTATOC PET/CT

International Nuclear Information System (INIS)

Sawicki, Lino M.; Deuschl, Cornelius; Beiderwellen, Karsten; Forsting, Michael; Umutlu, Lale; Ruhlmann, Verena; Poeppel, Thorsten D.; Bockisch, Andreas; Herrmann, Ken; Heusch, Philipp; Antoch, Gerald; Lahner, Harald; Fuehrer, Dagmar

2017-01-01

To compare the diagnostic performance of 68 Ga-DOTATOC PET/MRI and 68 Ga-DOTATOC PET/CT in the whole-body staging of patients with neuroendocrine tumours (NET). Thirty patients with histopathologically confirmed NET underwent PET/CT and PET/MRI in a single-injection protocol. PET/CT and PET/MRI scans were prospectively evaluated with regard to lesion count, localization, nature (NET/non-NET), and conspicuity (four-point scale). Histopathology and follow-up imaging served as the reference standards. The proportions of NET and non-NET lesions rated correctly were compared using McNemar's chi-squared test. The Wilcoxon test was used to assess differences in SUVmax and lesion conspicuity. The correlation between the SUVmax for the same lesions from each modality was analysed using Pearson's correlation coefficient (r). According to the reference standard, there were 197 lesions (142 NET, 55 non-NET). Lesion-based analysis showed a higher proportion of correctly rated NET lesions on PET/MRI than on PET/CT (90.8% vs. 86.7%, p = 0.031), whereas on PET/CT there was a higher proportion of correctly rated non-NET lesions (94.5% vs. 83.6%, p = 0.031). SUVmax was strongly correlated (r = 0.86; p < 0.001) and did not differ significantly (p = 0.35) between the modalities. Overall conspicuity and NET lesion conspicuity were higher on PET/MRI (both p < 0.01). Ga-DOTATOC PET/MRI yielded a higher proportion of correctly rated NET lesions and should be regarded as a valuable alternative to 68 Ga-DOTATOC PET/CT in whole-body staging of NET patients. (orig.)

The value of 18F-DOPA PET-CT in patients with medullary thyroid carcinoma: comparison with 18F-FDG PET-CT

International Nuclear Information System (INIS)

Beheshti, Mohsen; Poecher, Sigrid; Vali, Reza; Nader, Michael; Langsteger, Werner; Waldenberger, Peter; Broinger, Gabriele; Kohlfuerst, Susanne; Pirich, Christian; Dralle, Henning

2009-01-01

The purpose of this prospective study was to compare the value of DOPA PET-CT with FDG PET-CT in the detection of malignant lesions in patients with medullary thyroid carcinoma (MTC). Twenty-six consecutive patients (10 men, 16 women, mean age 59 ± 14 years) with elevated calcitonin levels were evaluated in this prospective study. DOPA and FDG PET-CT modalities were performed within a maximum of 4 weeks (median 7 days) in all patients. The data were evaluated on a patient- and lesion-based analysis. The final diagnosis of positive PET lesions was based on histopathological findings and/or imaging follow-up studies (i.e., DOPA and/or FDG PET-CT) for at least 6 months (range 6-24 months). In 21 (21/26) patients at least one malignant lesion was detected by DOPA PET, while only 15 (15/26) patients showed abnormal FDG uptake. DOPA PET provided important additional information in the follow-up assessment in seven (27%) patients which changed the therapeutic management. The patient-based analysis of our data demonstrated a sensitivity of 81% for DOPA PET versus 58% for FDG PET, respectively. In four (4/26) postoperative patients DOPA and FDG PET-CT studies were negative in spite of elevated serum calcitonin and CEA levels as well as abnormal pentagastrin tests. Overall 59 pathological lesions with abnormal tracer uptake were seen on DOPA and/or FDG PET studies. In the final diagnosis 53 lesions proved to be malignant. DOPA PET correctly detected 94% (50/53) of malignant lesions, whereas only 62% (33/53) of malignant lesions were detected with FDG PET. DOPA PET-CT showed superior results to FDG PET-CT in the preoperative and follow-up assessment of MTC patients. Therefore, we recommend DOPA PET-CT as a one-stop diagnostic procedure to provide both functional and morphological data in order to select those patients who may benefit from (re-)operation with curative intent as well as guiding further surgical procedures. (orig.)

Brain PET and functional MRI: why simultaneously using hybrid PET/MR systems?

Science.gov (United States)

Cecchin, Diego; Palombit, Alessandro; Castellaro, Marco; Silvestri, Erica; Bui, Franco; Barthel, Henryk; Sabri, Osama; Corbetta, Maurizio; Bertoldo, Alessandra

2017-12-01

between these two modalities. However, at least in one study the correlation at the level of gray, white matter, and whole brain is rather good (r=0.94, 0.8, 0.81 respectively). Finally, receptor studies show that simultaneous PET/fMRI could be a useful tool to characterize functional connectivity along with dynamic neuroreceptor adaptation in several physiological (e.g. working memory) or pathological (e.g. pain) conditions, with or without drug administrations. The simultaneous acquisition of PET (using a number of radiotracers) and functional MRI (using a number of sequences) offers exciting opportunities that we are just beginning to explore. The results thus far are promising in the evaluation of cerebral metabolism/flow, neuroreceptor adaptation, and network's energetic demand.

High impact of FDG-PET/CT in diagnostic strategies for ovarian cancer

International Nuclear Information System (INIS)

Zytoon, Ashraf Anas; Murakami, Koji; Eid, Hazem; El-Gammal, Mahmoud

2013-01-01

Background: Ovarian cancer has the highest mortality of all gynecologic malignancies. FDG-PET/CT was proven to be accurate for identification of primary ovarian tumors, regional lymph nodes, and distant metastases. Purpose: To evaluate ovarian masses at FDG-PET/CT in correlation with histopathologic findings. Material and Methods: Ninety-eight patients underwent whole body FDG-PET/CT examination. Eighty-six patients with primary ovarian cancer and 12 patients with metastatic disease to the ovaries were included. Results: PET/CT imaging was true-positive in 87/94 patients with malignant tumors. In 4/4 patients with benign tumors, PET/CT results were true-negative, with sensitivity of 92.6%, specificity 100%, total test accuracy 92.9%. Fifty-seven patients were diagnosed as stage IV ovarian cancer with distant metastasis. Conclusion: The anatomical/functional examination by FDG-PET/CT was proven to be valuable in increasing the diagnostic accuracy that can help improve patient management

Diagnostic performance of {sup 18}F-fluorothymidine PET/CT for primary colorectal cancer and its lymph node metastasis: comparison with {sup 18}F-fluorodeoxyglucose PET/CT

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Nakajo, Masatoyo [Kagoshima University, Graduate School of Medical and Dental Sciences, Department of Radiology, Kagoshima (Japan); Nanpuh Hospital, Department of Radiology, Kagoshima (Japan); Nakajo, Masayuki; Jinguji, Megumi; Fukukura, Yoshihiko [Kagoshima University, Graduate School of Medical and Dental Sciences, Department of Radiology, Kagoshima (Japan); Kajiya, Yoriko; Tani, Atushi [Nanpuh Hospital, Department of Radiology, Kagoshima (Japan); Nishimata, Nobuaki; Shimaoka, Shunji; Nihara, Tohru [Nanpuh Hospital, Department of Gastroenterology, Kagoshima (Japan); Aridome, Kuniaki [Nanpuh Hospital, Department of Surgery, Kagoshima (Japan); Tanaka, Sadao [Nanpuh Hospital, Department of Pathology, Kagoshima (Japan); Koriyama, Chihaya [Kagoshima University, Graduate School of Medical and Dental Sciences, Department of Epidemiology and Preventive Medicine, Kagoshima (Japan)

2013-08-15

To examine the diagnostic performance of {sup 18}F-fluorothymidine (FLT) PET/CT in primary and metastatic lymph node colorectal cancer foci in comparison with {sup 18}F-fluorodeoxyglucose (FDG) PET/CT. The study population comprised 28 patients with 30 newly diagnosed colorectal cancers who underwent surgical resection of the primary lesion and regional lymph nodes after both FLT and FDG PET/CT. The associations between SUVmax levels and pathological factors were evaluated using the Mann-Whitney U or Kruskal-Wallis test. Differences in diagnostic indexes for detecting nodal metastasis between the two tracers were estimated using the McNemar exact or {chi} {sup 2} test. All 30 primary cancers (43.0 {+-} 20.0 mm, range 14 - 85 mm) were visualized by both tracers, but none of the FLT SUVmax values exceeded the FDG SUVmax values in any of the primary cancers (6.6 {+-} 2.4 vs. 13.6 {+-} 5.8, p < 0.001). The sensitivity, specificity and accuracy for detecting nodal metastasis were 41 % (15/37), 98.8 % (493/499) and 94.8 % (508/536) for FDG PET/CT, and 32 % (12/37), 98.8 % (493/499) and 94.2 % (505/536) for FLT PET/CT, respectively. The sensitivity (p = 0.45), specificity (p = 0.68) and accuracy (p = 0.58) were not different between the tracers. Nodal uptake of FLT and FDG was discordant in 7 (19 %) of 37 metastatic nodes. There were ten concordant true-positive nodes of which six showed higher FDG SUVmax and four showed higher FLT SUVmax, but the difference between FDG and FLT SUVmax was not significant (5.56 {+-} 3.55 and 3.62 {+-} 1.45, respectively; p = 0.22). FLT has the same potential as FDG in PET/CT for the diagnosis of primary and nodal foci of colorectal cancer despite significantly lower FLT uptake in primary foci. (orig.)

SU-E-J-254: Evaluating the Role of Mid-Treatment and Post-Treatment FDG-PET/CT in Predicting Progression-Free Survival and Distant Metastasis of Anal Cancer Patients Treated with Chemoradiotherapy

International Nuclear Information System (INIS)

Zhang, H; Wang, J; Chuong, M; D’Souza, W; Choi, W; Lu, W; Latifi, K; Hoffe, S; Moros, E; Saeed, Nadia; Tan, S; Shridhar, R

2015-01-01

Purpose: To evaluate the role of mid-treatment and post-treatment FDG-PET/CT in predicting progression-free survival (PFS) and distant metastasis (DM) of anal cancer patients treated with chemoradiotherapy (CRT). Methods: 17 anal cancer patients treated with CRT were retrospectively studied. The median prescription dose was 56 Gy (range, 50–62.5 Gy). All patients underwent FDG-PET/CT scans before and after CRT. 16 of the 17 patients had an additional FDG-PET/CT image at 3–5 weeks into the treatment (denoted as mid-treatment FDG-PET/CT). 750 features were extracted from these three sets of scans, which included both traditional PET/CT measures (SUVmax, SUVpeak, tumor diameters, etc.) and spatialtemporal PET/CT features (comprehensively quantify a tumor’s FDG uptake intensity and distribution, spatial variation (texture), geometric property and their temporal changes relative to baseline). 26 clinical parameters (age, gender, TNM stage, histology, GTV dose, etc.) were also analyzed. Advanced analytics including methods to select an optimal set of predictors and a model selection engine, which identifies the most accurate machine learning algorithm for predictive analysis was developed. Results: Comparing baseline + mid-treatment PET/CT set to baseline + posttreatment PET/CT set, 14 predictors were selected from each feature group. Same three clinical parameters (tumor size, T stage and whether 5-FU was held during any cycle of chemotherapy) and two traditional measures (pre- CRT SUVmin and SUVmedian) were selected by both predictor groups. Different mix of spatial-temporal PET/CT features was selected. Using the 14 predictors and Naive Bayes, mid-treatment PET/CT set achieved 87.5% accuracy (2 PFS patients misclassified, all local recurrence and DM patients correctly classified). Post-treatment PET/CT set achieved 94.0% accuracy (all PFS and DM patients correctly predicted, 1 local recurrence patient misclassified) with logistic regression, neural network or

SU-E-J-254: Evaluating the Role of Mid-Treatment and Post-Treatment FDG-PET/CT in Predicting Progression-Free Survival and Distant Metastasis of Anal Cancer Patients Treated with Chemoradiotherapy

Energy Technology Data Exchange (ETDEWEB)

Zhang, H; Wang, J; Chuong, M; D’Souza, W; Choi, W; Lu, W [University of Maryland School of Medicine, Baltimore, MD (United States); Latifi, K; Hoffe, S; Moros, E [Moffitt Cancer Center, Tampa, FL (United States); Saeed, Nadia [Brwon University, Providence, RI (United States); Tan, S [Huazhong University of Science & Technology, Wuhan (China); Shridhar, R [Florida Hospital, Orlando, FL (United States)

2015-06-15

Purpose: To evaluate the role of mid-treatment and post-treatment FDG-PET/CT in predicting progression-free survival (PFS) and distant metastasis (DM) of anal cancer patients treated with chemoradiotherapy (CRT). Methods: 17 anal cancer patients treated with CRT were retrospectively studied. The median prescription dose was 56 Gy (range, 50–62.5 Gy). All patients underwent FDG-PET/CT scans before and after CRT. 16 of the 17 patients had an additional FDG-PET/CT image at 3–5 weeks into the treatment (denoted as mid-treatment FDG-PET/CT). 750 features were extracted from these three sets of scans, which included both traditional PET/CT measures (SUVmax, SUVpeak, tumor diameters, etc.) and spatialtemporal PET/CT features (comprehensively quantify a tumor’s FDG uptake intensity and distribution, spatial variation (texture), geometric property and their temporal changes relative to baseline). 26 clinical parameters (age, gender, TNM stage, histology, GTV dose, etc.) were also analyzed. Advanced analytics including methods to select an optimal set of predictors and a model selection engine, which identifies the most accurate machine learning algorithm for predictive analysis was developed. Results: Comparing baseline + mid-treatment PET/CT set to baseline + posttreatment PET/CT set, 14 predictors were selected from each feature group. Same three clinical parameters (tumor size, T stage and whether 5-FU was held during any cycle of chemotherapy) and two traditional measures (pre- CRT SUVmin and SUVmedian) were selected by both predictor groups. Different mix of spatial-temporal PET/CT features was selected. Using the 14 predictors and Naive Bayes, mid-treatment PET/CT set achieved 87.5% accuracy (2 PFS patients misclassified, all local recurrence and DM patients correctly classified). Post-treatment PET/CT set achieved 94.0% accuracy (all PFS and DM patients correctly predicted, 1 local recurrence patient misclassified) with logistic regression, neural network or

18F-FDG PET in children with lymphomas

International Nuclear Information System (INIS)

Depas, Gisele; Barsy, Caroline De; Foidart, Jacqueline; Rigo, Pierre; Hustinx, Roland; Jerusalem, Guy; Hoyoux, Claire; Dresse, Marie-Francoise; Fassotte, Marie-France; Paquet, Nancy

2005-01-01

The aim of this study was to retrospectively evaluate the performance of positron emission tomography (PET) with 18 F-fluorodeoxyglucose ( 18 F-FDG) in children with lymphomas, at various stages of their disease. Twenty-eight children (mean age 12.5 years, 14 girls, 14 boys) with Hodgkin's disease (HD, n=17) or non-Hodgkin's lymphoma (NHL, n=11) were evaluated. Patients were investigated at initial staging (n=19), early in the course of treatment (n=19), at the end of treatment (n=16) and during long-term follow-up (n=19). A total of 113 whole-body PET studies were performed on dedicated scanners. PET results were compared with the results of conventional methods (CMs) such as physical examination, laboratory studies, chest X-rays, computed tomography, magnetic resonance imaging, ultrasonography and bone scan when available. At initial evaluation (group 1), PET changed the disease stage and treatment in 10.5% of the cases. In early evaluation of the response to treatment (group 2), PET failed to predict two relapses and one incomplete response to treatment. In this group, however, PET did not show any false positive results. There were only 4/75 false positive results for PET among patients studied at the end of treatment (group 3, specificity 94%) or during the systematic follow-up (group 4, specificity 95%), as compared with 27/75 for CMs (specificity 54% and 66%, respectively). 18 F-FDG-PET is a useful tool for evaluating children with lymphomas. Large prospective studies are needed to appreciate its real impact on patient management. (orig.)

Evaluation of {sup 68}Ga-DOTATOC PET/MRI for whole-body staging of neuroendocrine tumours in comparison with {sup 68}Ga-DOTATOC PET/CT

Energy Technology Data Exchange (ETDEWEB)

Sawicki, Lino M. [University Dusseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Dusseldorf (Germany); University Duisburg-Essen, Department of Nuclear Medicine, Medical Faculty, Essen (Germany); Deuschl, Cornelius; Beiderwellen, Karsten; Forsting, Michael; Umutlu, Lale [University Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Medical Faculty, Essen (Germany); Ruhlmann, Verena; Poeppel, Thorsten D.; Bockisch, Andreas; Herrmann, Ken [University Duisburg-Essen, Department of Nuclear Medicine, Medical Faculty, Essen (Germany); Heusch, Philipp; Antoch, Gerald [University Dusseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Dusseldorf (Germany); Lahner, Harald; Fuehrer, Dagmar [University Duisburg-Essen, Department of Endocrinology and Metabolism, Endocrine Tumour Center at WTZ and ENETS Center of Excellence, Medical Faculty, Essen (Germany); Endocrine Tumour Center at WTZ and ENETS Center of Excellence, Essen (Germany)

2017-10-15

To compare the diagnostic performance of {sup 68}Ga-DOTATOC PET/MRI and {sup 68}Ga-DOTATOC PET/CT in the whole-body staging of patients with neuroendocrine tumours (NET). Thirty patients with histopathologically confirmed NET underwent PET/CT and PET/MRI in a single-injection protocol. PET/CT and PET/MRI scans were prospectively evaluated with regard to lesion count, localization, nature (NET/non-NET), and conspicuity (four-point scale). Histopathology and follow-up imaging served as the reference standards. The proportions of NET and non-NET lesions rated correctly were compared using McNemar's chi-squared test. The Wilcoxon test was used to assess differences in SUVmax and lesion conspicuity. The correlation between the SUVmax for the same lesions from each modality was analysed using Pearson's correlation coefficient (r). According to the reference standard, there were 197 lesions (142 NET, 55 non-NET). Lesion-based analysis showed a higher proportion of correctly rated NET lesions on PET/MRI than on PET/CT (90.8% vs. 86.7%, p = 0.031), whereas on PET/CT there was a higher proportion of correctly rated non-NET lesions (94.5% vs. 83.6%, p = 0.031). SUVmax was strongly correlated (r = 0.86; p < 0.001) and did not differ significantly (p = 0.35) between the modalities. Overall conspicuity and NET lesion conspicuity were higher on PET/MRI (both p < 0.01). Ga-DOTATOC PET/MRI yielded a higher proportion of correctly rated NET lesions and should be regarded as a valuable alternative to {sup 68}Ga-DOTATOC PET/CT in whole-body staging of NET patients. (orig.)

Dual modality CT/PET imaging in lung cancer staging

International Nuclear Information System (INIS)

Diaz, Gabriel A.

2005-01-01

Purpose: To compare the diagnostic capability of PET-HCT image fusion and helical computed tomography (HCT) for nodal and distant metastases detection in patients with lung cancer. Material and methods: Between February, 2003 and March, 2004 sixty-six consecutive lung cancer patients (45 men and 21 women, mean ages: 63 years old, range: 38 to 96 years old) who underwent HCT and PET-HCT fusion imaging were evaluated retrospectively. All patients had histological confirmation of lung cancer and a definitive diagnosis established on the basis of pathology results and/or clinical follow-up. Results: For global nodal staging (hilar and mediastinal) HCT showed a sensitivity, specificity, positive predictive value and negative predictive value of 72%, 47%, 62% and 58% respectively, versus 94%, 77%, 83% and 92% corresponding to PET-HCT examination. For assessment of advanced nodal stage (N3) PET-HCT showed values of 92%, 100%, 100% and 98% respectively. For detection of distant metastasis, HCT alone had values of 67%, 93%, 84% and 83% respectively versus 100%, 98%, 96% and 100% for the PET-HCT fusion imaging. In 20 (30%) patients under-staged or over-staged on the basis of HCT results, PET-HCT allowed accurate staging. Conclusions: PET-HCT fusion imaging was more effective than HCT alone for nodal and distant metastasis detection and oncology staging. (author)

Improved clinical staging of esophageal cancer with FDG-PET

International Nuclear Information System (INIS)

Kim, Young Hwan; Choi, Joon Young; Lee, Kyung Soo; Choi, Yong Soo; Lee, Eun Jeong; Chung, Hyun Woo; Lee, Su Jin; Lee, Kyung Han; Shim, Young Mog; Kim, Byung Tae

2004-01-01

Since preoperative staging in esophageal cancer is important in both therapy and prognosis, there had been many efforts to improve its accuracy. Recent studies indicate that whole body FDG-PET has high sensitivity in detection of metastasis in esophageal cancer. Therefore, we added FDG-PET to other conventional methods in staging esophageal cancer to evaluate the usefulness of this method. Subjects were 142 esophageal cancer patients (average 62.3±8.3 yrs) who received CT and PET just before operation. First, we compared N stage and M stage of the CT or PET with those of the post-operative results. Then we compared the stage according to the EUS (T stage) and CT (N and M stage) or EUS (T stage) and CT and PET (N and M stage) to that according to the post-operative results. Among 142 patients, surgical staging of 69 were N0 and 73 were N1. In M staging, 128 were M0 and 14 were M1. Sensitivity, specificity, and accuracy of N staging were 35.6%, 89.9%, 62.0% with CT and 58.9%, 71.0%, 64.7% with PET, respectively. In M staging, 14.3%, 96.9%, 88.7% with CT and 50.0%, 94.5%, 90.1% with PET, respectively. The concordances of [EUS+CT] and [EUS+CT+PET] with post-operative results were 41.2% and 54.6%, respectively and there was significant improvement of staging with additional PET scan (p<0.005). The concordance of [EUS+CT+PET] with post-operative result was significantly increased compared to that of [EUS+CT]. Thus, the addition of FDG-PET with other conventional methods may enable more accurate preoperative staging

18F-FDG PET和PET/CT显像对原发不明转移癌诊断价值的系统性综述和Meta分析%Role of 18F-FDG PET and PET/CT in detection of unknown primary tumor: a systematic review and Meta-analysis of the literature

Institute of Scientific and Technical Information of China (English)

杨忠毅; 徐俊彦; 胡四龙

2011-01-01

目的:研究F-FDG PET和PET/CT显像寻找原发灶的价值.方法:收集2010年3月31日前公开发表的关于F-FDG PET或PET/CT显像用于寻找原发灶价值的中英文文献,并进行数据提取和方法学质量评估.采用Meta分析的方法计算综合灵敏度(Se)、特异性(Sp)、阳性似然比(LR+)、阴性似然比(LR-)和诊断优势比(DOR),并绘制综合受试者工作特征(SROC)曲线.结果:共有24篇文献纳入(PET显像14篇,PET/CT显像10篇).F-FDG PET和PET/CT显像对原发灶的正确检出率为40.86%(344/842),两者分别为37.60%(144/383)和43.57%(200/459).检出的原发灶主要位于肺、扁桃体和胃肠道.PET显像的综合Se、Sp、LR+、LR-、DOR及相应的95%可信区间(CI)分别为88%(82%～92%)、80%(74%～85%)、3.55(2.14～5.88)、0.24(0.16-0.36)和24.94(11.36～54.78);PET/CT显像则分别为90%(86%～94%)、84%(79%～89%)、5.19(3.48～7.74)、0.07(0.02～0.25)和80.02(20.42～313.48).SROC曲线下面积分别为0.9074和0.8758,Q*值为0.8393和0.8063.易产生假阳性的部位主要为肺、扁桃体和口咽部,而假阴性则好发于乳腺、扁桃体、舌根和骨骼等.结论:F-FDG PET和PET/CT显像对原发不明转移癌原发灶的检出具有较高的价值.%Objective: To evaluate the diagnostic accuracy of 18F-FDG PET and PET/CT in the detection of primary tumors. Methods: Publications were collected from the English and Chinese literatures on PET or PET/CT imaging in detecting primary tumors of patients presenting with carcinoma of unknown primary (CUP) unidentified by conventional workup(before March 31, 2010). Systematic methods were used to identify, select, and evaluate the methodological quality of the studies. The pooled sensitivity, specificity, positive likelihood ratio(LR+), negative likelihood ratio(LR-), diagnostic odds ratio(DOR) and summary receiver operating characteristic(SROC) curves were obtained through Meta analysis. Results: 24 studies were analyzed(l4 studies of PET and

Observing storm surges in the Bay of Bengal from satellite altimetry

Digital Repository Service at National Institute of Oceanography (India)

Antony, C.; Testut, L.; Unnikrishnan, A.S.

with the large tidal ranges give rise to extreme sea level in the head bay and surrounding regions. Moreover, low-lying nature of the coast and the dense population in the region make the coasts of the northern Bay of Bengal highly vulnerable to storm surges...-gauge data during the passage of the hurricane Igor that crossed Newfoundland in 2010. For this event, St. John’s tide gauge recorded a maximum surge of 94 cm and Jason-2 (the track located 89 km away from the tide-gauge station) showed positive sea-level...

MRI fused with prone FDG PET/CT improves the primary tumour staging of patients with breast cancer

Energy Technology Data Exchange (ETDEWEB)

Garcia-Velloso, Maria J.; Ribelles, Maria J.; Rodriguez, Macarena; Sancho, Lidia; Prieto, Elena [Clinica Universidad de Navarra, Department of Nuclear Medicine, Pamplona (Spain); Fernandez-Montero, Alejandro [Clinica Universidad de Navarra, Department of Occupational Medicine, Pamplona (Spain); Santisteban, Marta [Clinica Universidad de Navarra, Department of Oncology, Pamplona (Spain); Rodriguez-Spiteri, Natalia; Martinez-Regueira, Fernando [Clinica Universidad de Navarra, Department of Surgery, Pamplona (Spain); Idoate, Miguel A. [Clinica Universidad de Navarra, Department of Pathology, Pamplona (Spain); Elizalde, Arlette; Pina, Luis J. [Clinica Universidad de Navarra, Department of Radiology, Pamplona (Spain)

2017-08-15

Our aim was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) fused with prone 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in primary tumour staging of patients with breast cancer. This retrospective study evaluated 45 women with 49 pathologically proven breast carcinomas. MRI and prone PET-CT scans with time-of-flight and point-spread-function reconstruction were performed with the same dedicated breast coil. The studies were assessed by a radiologist and a nuclear medicine physician, and evaluation of fused images was made by consensus. The final diagnosis was based on pathology (90 lesions) or follow-up ≥ 24 months (17 lesions). The study assessed 72 malignant and 35 benign lesions with a median size of 1.8 cm (range 0.3-8.4 cm): 31 focal, nine multifocal and nine multicentric cases. In lesion-by-lesion analysis, sensitivity, specificity, positive and negative predictive values were 97%, 80%, 91% and 93% for MRI, 96%, 71%, 87%, and 89% for prone PET, and 97%. 94%, 97% and 94% for MRI fused with PET. Areas under the curve (AUC) were 0.953, 0.850, and 0.983, respectively (p < 0.01). MRI fused with FDG-PET is more accurate than FDG-PET in primary tumour staging of breast cancer patients and increases the specificity of MRI. (orig.)

Thermal oxidative degradation behaviours of flame-retardant thermotropic liquid crystal copolyester/PET blends

International Nuclear Information System (INIS)

Du Xiaohua; Zhao Chengshou; Wang Yuzhong; Zhou Qian; Deng Yi; Qu Minghai; Yang Bing

2006-01-01

The flame retardancy and the thermal oxidative degradation behaviors of the blend of poly(ethylene terephthalate) (PET) with a kind of phosphorus-containing thermotropic liquid crystal copolyester (TLCP) with high flame retardancy (limited oxygen index, 70%) have been investigated by oxygen index test (LOI), UL-94 rating and thermogravimetric analysis (TGA) in air. The results show that TLCP can dramatically improve the flame retardancy and the melt dripping behavior of PET. Moreover, the apparent activation energies of thermal oxidative degradation of the blends were evaluated using Kissinger and Flynn-Wall-Ozawa methods. It is found that addition of TLCP improve thermal stability and restrain thermal decomposition of PET in air, especially at the primary degradation stage. Py-GC/MS analysis shows that there are remarkable changes in the pyrolysis products when TLCP are blended into PET. The interaction between TLCP and PET has changed their thermal oxidative degradation mechanism

Modification of patient management when using FDG-PET in detection of recurrences of colorectal cancer: 18 month-experience

International Nuclear Information System (INIS)

Montravers, F.; Grahek, D.; Kerrou, K.; Younsi, N.; Petegnief, Y.; Talbot, J.N.

2002-01-01

Full text: The aim of this study was to evaluate the impact of [F-18] - FDG - PET on managing patients with colorectal cancer. From January 2000 to July 2001, 164 examinations were performed by the team of hospital Tenon using a 3D dedicated PET System (C-PET, ADAC) for suspicion or recurrence of colorectal cancer (53 % of the cases), for search for other localization when one or more resectable(s) lesion(s) was (were) known (37 %) or for evaluation of the therapeutic efficacy (10 %). To evaluate the impact of PET imaging on patient management, a post PET questionnaire (corresponding to the French translation of the questionnaire presented by J. Meta et al.) was sent to the referring physician. 94 responses are currently available, corresponding to: no change (n = 42), change from no treatment to surgery (n =11), change from no treatment to medical treatment (n = 11), change from surgery to medical treatment (n - 9), change from medical treatment to no treatment (n = 5), change from medical treatment to surgery (n = 4), change from surgery to no treatment (n = 4), change in medical approach (n = 3), change in surgical approach (n = 2), change from no treatment to radiotherapy (n = 1), change from radiotherapy to medical treatment (n = 1), change from medical treatment to radiotherapy (n = 1). In summary, among 94 responses from referring physicians (corresponding to 57 % of the examinations), changes in patient management were reported for 52 of the 94 patients (55 %). This result confirms, in France, the major impact of FDG-PET on the management of recurrences of colorectal cancer, as reported by the referring physician, already demonstrated in California (62 % in the 60 patients of Meta et al). (author)

FDG-PET/contrast-enhanced CT as a post-treatment tool in head and neck squamous cell carcinoma: comparison with FDG-PET/non-contrast-enhanced CT and contrast-enhanced CT

Energy Technology Data Exchange (ETDEWEB)

Suenaga, Yuko; Kitajima, Kazuhiro; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Ishihara, Takeaki; Sasaki, Ryohei [Kobe University Graduate, School of Medicine, Department of Radiology, Division of Radiation Oncology, Kobe (Japan); Otsuki, Naoki; Nibu, Ken-ichi [Kobe University Graduate, School of Medicine, Department of Otolaryngology-Head and Neck Surgery, Kobe (Japan); Minamikawa, Tsutomu [Kobe University Graduate School of Medicine, Department of Oral and Maxillofacial Surgery, Kobe (Japan); Kiyota, Naomi [Kobe University Hospital, Department of Medical Oncology and Hematology, Kobe (Japan)

2016-04-15

To evaluate the accuracy of PET/CT using {sup 18}F-fluorodeoxyglucose (FDG) with IV contrast for suspected recurrent head and neck squamous cell carcinoma (HNSCC). One hundred and seventy patients previously treated for HNSCC underwent PET/CT, consisting of non-contrast-enhanced and contrast-enhanced CT, to investigate suspected recurrence. Diagnostic performance of PET/contrast-enhanced CT (PET/ceCT), PET/non-contrast-enhanced CT (PET/ncCT) and contrast-enhanced CT (ceCT) for local or regional recurrence, distant metastasis, overall recurrence and second primary cancer was evaluated. The reference standard included histopathology, treatment change and imaging follow-up. The patient-based areas under the receiver operating characteristic curves (AUC) for ceCT, PET/ncCT and PET/ceCT were 0.82, 0.96 and 0.98 for local recurrence, 0.73, 0.86 and 0.86 for regional recurrence, 0.86, 0.91 and 0.92 for distant metastasis, 0.72, 0.86 and 0.87 for overall recurrence, and 0.86, 0.89 and 0.91 for a second primary cancer. Both PET/ceCT and PET/ncCT statistically showed larger AUC than ceCT for recurrence, and the difference between PET/ceCT and PET/ncCT for local recurrence reached a significant level (p = 0.039). The accuracy of PET/ceCT for diagnosing overall recurrence was high, irrespective of the time interval after the last treatment (83.3-94.1 %). FDG-PET/CT was a more accurate HNSCC restaging tool than ceCT. The added value of ceCT at FDG-PET/CT is minimal. (orig.)

PET with a coincidence gamma camera: results in selected oncological questions

International Nuclear Information System (INIS)

Lauer, I.; Haase, A; Adam, S.; Prueter, I.; Richter, E.; Baehre, M.

2001-01-01

Since early 1997, about 1660 investigations with coincidence gamma camera PET (CGC-PET) have been performed in our department, mostly undertaken for oncological questions. Based on these data, several retrospective and prospective studies were performed. In the following, the results in CUP (cancer of unknown primary) syndrome, melanoma and malignant lymphoma are presented. Methods: CGC-PET was performed after application of 250-350 MBq [ 18 F]FDG using a coincidence double head gamma camera with 19 mm Nal cristal. CUP-Syndrome: After completing conventional diagnostic procedures, 32 patients have been examined in a prospective study, including 25 patients with recently detected CUP and 7 patients undergoing restaging after therapy. Localization of the primary tumor was successful in 12 (38%) cases. Melanoma: We evaluated 50 studies in 41 patients suffering from melanoma, retrospectively. CGC-PET showed a sensitivity of 76%, and a specificity of 94%. In comparison to conventional diagnostic methods, CGC-PET delineated important additional information in 16%. CGC-PET was superior to morphological diagnostic tools in the differentiation between residual scar tissue and active tumor following immunochemotherapy. Malignant lymphoma: 29 CGC-PET in 29 patients were performed for staging of malignant lymphoma, sensitivity was 86% versus 88% for CT. Overall CGC-PET showed additional information to conventional diagnostic methods, but revealed problems in detecting small infiltrations of organs. In restaging malignant melanoma (26 patients, 33 studies), specificity of CGC-PET was superior to conventional diagnostics (92% versus 35%). (orig.) [de

Estimation of Input Function from Dynamic PET Brain Data Using Bayesian Blind Source Separation

Czech Academy of Sciences Publication Activity Database

Tichý, Ondřej; Šmídl, Václav

2015-01-01

Roč. 12, č. 4 (2015), s. 1273-1287 ISSN 1820-0214 R&D Projects: GA ČR GA13-29225S Institutional support: RVO:67985556 Keywords : blind source separation * Variational Bayes method * dynamic PET * input function * deconvolution Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.623, year: 2015 http://library.utia.cas.cz/separaty/2015/AS/tichy-0450509.pdf

Post-therapy surveillance of patients with uterine cancers: value of integrated FDG PET/CT in the detection of recurrence

International Nuclear Information System (INIS)

Sironi, Sandro; Picchio, Maria; Bettinardi, Valentino; Landoni, Claudio; Galimberti, Stefania; Signorelli, Mauro; Perego, Patrizia; Mangioni, Costantino; Messa, Cristina; Fazio, Ferruccio

2007-01-01

The purpose of this study was to prospectively determine the diagnostic accuracy of PET/CT in the detection of recurrence in patients with treated uterine cancers. Twenty-five women, ranging in age from 37 to 79 years (mean 58.9 years), who underwent primary surgical treatment for either a cervical or an endometrial cancer met the inclusion criterion of the study, which was suspicion of recurrence based on results of routine follow-up procedures. PET/CT was performed after administration of 18 F-fluorodeoxyglucose (FDG); two readers interpreted the images in consensus. Histopathological findings or correlation with results of subsequent clinical and imaging follow-up examinations served as the reference standard. Diagnostic accuracy of PET/CT was reported in terms of the proportion of correctly classified patients and lesion sites. Tumour recurrence was found at histopathological analysis or follow-up examinations after PET/CT in 14 (56%) of the 25 patients. Patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT for detection of tumour recurrence were 92.9%, 100.0%, 100.0%, 91.7% and 96.0%, respectively. Lesion site-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT were 94.7%, 99.5%, 94.7%, 99.5% and 99.0%, respectively. This preliminary study shows that PET/CT may be an accurate method for the evaluation of recurrence in patients who have been treated for uterine cancers and are undergoing follow-up. (orig.)

[18F]Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET)/Computed Tomography (CT) in Suspected Recurrent Breast Cancer: A Prospective Comparative Study of Dual-Time-Point FDG-PET/CT, Contrast-Enhanced CT, and Bone Scintigraphy.

Science.gov (United States)

Hildebrandt, Malene Grubbe; Gerke, Oke; Baun, Christina; Falch, Kirsten; Hansen, Jeanette Ansholm; Farahani, Ziba Ahangarani; Petersen, Henrik; Larsen, Lisbet Brønsro; Duvnjak, Sandra; Buskevica, Inguna; Bektas, Selma; Søe, Katrine; Jylling, Anne Marie Bak; Ewertz, Marianne; Alavi, Abass; Høilund-Carlsen, Poul Flemming

2016-06-01

To prospectively investigate the diagnostic accuracy of [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with dual-time-point imaging, contrast-enhanced CT (ceCT), and bone scintigraphy (BS) in patients with suspected breast cancer recurrence. One hundred women with suspected recurrence of breast cancer underwent 1-hour and 3-hour FDG-PET/CT, ceCT, and BS within approximately 10 days. The study was powered to estimate the precision of the individual imaging tests. Images were visually interpreted using a four-point assessment scale, and readers were blinded to other test results. The reference standard was biopsy along with treatment decisions and clinical follow-up (median, 17 months). FDG-PET/CT resulted in no false negatives and fewer false positives than the other imaging techniques. Accuracy of results were similar for 1-hour and 3-hour FDG-PET/CT. For distant recurrence, the area under the receiver operating curve was 0.99 (95% CI, 0.97 to 1) for FDG-PET/CT, 0.84 (95% CI, 0.73 to 0.94) for ceCT, and 0.86 (95% CI, 0.77 to 0.94) for the combined ceCT+BS. Of 100 patients, 22 (22%) were verified with distant recurrence, and 18 of these had bone involvement. Nineteen patients (19%) had local recurrence only. In exploratory analyses, diagnostic accuracy of FDG-PET/CT was better than ceCT alone or ceCT combined with BS in diagnosing distant, bone, and local recurrence, shown by a greater area under the receiver operating curve and higher sensitivity, specificity, and superior likelihood ratios. FDG-PET/CT was accurate in diagnosing recurrence in breast cancer patients. It allowed for distant recurrence to be correctly ruled out and resulted in only a small number of false-positive cases. Exploratory findings suggest that FDG-PET/CT has greater accuracy than conventional imaging technologies in this patient group. © 2016 by American Society of Clinical Oncology.

Evaluation of diagnostic performance of whole-body simultaneous PET/MRI in pediatric lymphoma

International Nuclear Information System (INIS)

Ponisio, Maria Rosana; Laforest, Richard; Khanna, Geetika; McConathy, Jonathan

2016-01-01

Whole-body 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is the standard of care for lymphoma. Simultaneous PET/MRI (magnetic resonance imaging) is a promising new modality that combines the metabolic information of PET with superior soft-tissue resolution and functional imaging capabilities of MRI while decreasing radiation dose. There is limited information on the clinical performance of PET/MRI in the pediatric setting. This study evaluated the feasibility, dosimetry, and qualitative and quantitative diagnostic performance of simultaneous whole-body FDG-PET/MRI in children with lymphoma compared to PET/CT. Children with lymphoma undergoing standard of care FDG-PET/CT were prospectively recruited for PET/MRI performed immediately after the PET/CT. Images were evaluated for quality, lesion detection and anatomical localization of FDG uptake. Maximum and mean standardized uptake values (SUV max/mean ) of normal organs and SUV max of the most FDG-avid lesions were measured for PET/MRI and PET/CT. Estimation of radiation exposure was calculated using specific age-related factors. Nine PET/MRI scans were performed in eight patients (mean age: 15.3 years). The mean time interval between PET/CT and PET/MRI was 51 ± 10 min. Both the PET/CT and PET/MRI exams had good image quality and alignment with complete (9/9) concordance in response assessment. The SUVs from PET/MRI and PET/CT were highly correlated for normal organs (SUV mean r 2 : 0.88, P<0.0001) and very highly for FDG-avid lesions (SUV max r 2 : 0.94, P=0.0002). PET/MRI demonstrated an average percent radiation exposure reduction of 39% ± 13% compared with PET/CT. Simultaneous whole-body PET/MRI is clinically feasible in pediatric lymphoma. PET/MRI performance is comparable to PET/CT for lesion detection and SUV measurements. Replacement of PET/CT with PET/MRI can significantly decrease radiation dose from diagnostic imaging in children. (orig.)

Semiautomated analysis of small-animal PET data.

Science.gov (United States)

Kesner, Adam L; Dahlbom, Magnus; Huang, Sung-Cheng; Hsueh, Wei-Ann; Pio, Betty S; Czernin, Johannes; Kreissl, Michael; Wu, Hsiao-Ming; Silverman, Daniel H S

2006-07-01

The objective of the work reported here was to develop and test automated methods to calculate biodistribution of PET tracers using small-animal PET images. After developing software that uses visually distinguishable organs and other landmarks on a scan to semiautomatically coregister a digital mouse phantom with a small-animal PET scan, we elastically transformed the phantom to conform to those landmarks in 9 simulated scans and in 18 actual PET scans acquired of 9 mice. Tracer concentrations were automatically calculated in 22 regions of interest (ROIs) reflecting the whole body and 21 individual organs. To assess the accuracy of this approach, we compared the software-measured activities in the ROIs of simulated PET scans with the known activities, and we compared the software-measured activities in the ROIs of real PET scans both with manually established ROI activities in original scan data and with actual radioactivity content in immediately harvested tissues of imaged animals. PET/atlas coregistrations were successfully generated with minimal end-user input, allowing rapid quantification of 22 separate tissue ROIs. The simulated scan analysis found the method to be robust with respect to the overall size and shape of individual animal scans, with average activity values for all organs tested falling within the range of 98% +/- 3% of the organ activity measured in the unstretched phantom scan. Standardized uptake values (SUVs) measured from actual PET scans using this semiautomated method correlated reasonably well with radioactivity content measured in harvested organs (median r = 0.94) and compared favorably with conventional SUV correlations with harvested organ data (median r = 0.825). A semiautomated analytic approach involving coregistration of scan-derived images with atlas-type images can be used in small-animal whole-body radiotracer studies to estimate radioactivity concentrations in organs. This approach is rapid and less labor intensive than are

Imaging and PET - PET/CT imaging

International Nuclear Information System (INIS)

Von Schulthess, G.K.; Hany, Th.F.

2008-01-01

PET/CT has grown because the lack of anatomic landmarks in PET makes 'hardware-fusion' to anatomic cross-sectional data extremely useful. Addition of CT to PET improves specificity, but also sensitivity, and adding PET to CT adds sensitivity and specificity in tumor imaging. The synergistic advantage of adding CT is that the attenuation correction needed for PET data can also be derived from the CT data. This makes PET-CT 25-30% faster than PET alone, leading to higher patient throughput and a more comfortable examination for patients typically lasting 20 minutes or less. FDG-PET-CT appears to provide relevant information in the staging and therapy monitoring of many tumors, such as lung carcinoma, colorectal cancer, lymphoma, gynaecological cancers, melanoma and many others, with the notable exception of prostatic cancer. for this cancer, choline derivatives may possibly become useful radiopharmaceuticals. The published literature on the applications of FDG-PET-CT in oncology is still limited but several designed studies have demonstrated the benefits of PET-CT. (authors)

Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests.

Science.gov (United States)

Demir, Mustafa; Toklu, Türkay; Abuqbeitah, Mohammad; Çetin, Hüseyin; Sezgin, H Sezer; Yeyin, Nami; Sönmezoğlu, Kerim

2018-02-01

The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated aspects were spatial resolution, sensitivity, scatter fraction, count rate performance, image quality, count loss and random events correction accuracy. The findings of this study demonstrated superior sensitivity (~ 4 folds) of PET scanner in PET/MR compared to PET/CT system. Image quality test exhibited higher contrast in PET/MR (~ 9%) compared with PET/CT. The scatter fraction of PET/MR was 43.4% at noise equivalent count rate (NECR) peak of 218 kcps and the corresponding activity concentration was 17.7 kBq/cc. Whereas the scatter fraction of PET/CT was found as 39.2% at NECR peak of 72 kcps and activity concentration of 24.3 kBq/cc. The percentage error of the random event correction accuracy was 3.4% and 3.1% in PET/MR and PET/CT, respectively. It was concluded that PET/MR system is about 4 times more sensitive than PET/CT, and the contrast of hot lesions in PET/MR was ~ 9% higher than PET/CT. These outcomes also emphasize the possibility to achieve excellent clinical PET images with low administered dose and/or a short acquisition time in PET/MR.

The clinical role of "1"8F-FDG PET/CT in diagnosis of the peritoneal carcinomatosis

International Nuclear Information System (INIS)

Wang Xiaoyan; Zhang Xiangsong; Chen Zhifeng; Li Ziping; Li Fang; Rao Guohui; Shi Xinchong; Hu Ping

2010-01-01

Objective: To evaluate the clinical role of "1"8F-fluorodeoxyglucose (FDG) PET/CT in diagnosis of the peritoneal carcinomatosis. Methods: The "1"8F-FDG PET/CT scan was performed in 22 patients. All had documented malignancy and had ascites. Histopathology. or clinical follow-up was 'gold standard' for diagnostic accuracy in PET/CT scan. Results: Of these 22 patients, 18 had positive "1"8F- FDG PET/CT findings. Sixteen were peritoneal carcinomatosis and 2 were peritoneal tuberculosis. Four patients had negative "1"8F-FDG PET/CT findings. Three were peritonitis and 1 was peritoneal carcinomatosis. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of "1"8F-FDG PET/CT in diagnosing peritoneal carcinomatosis were 94.1% (16/17), 3/5, 88.9% (16/18), 3/4, and 86.4% (19/22). Conclusions: "1"8F-FDG PET/CT had high sensitivity in detecting peritoneal carcinomatosis. The most common false positive for "1"8F-FDG PET/CT in ascites was peritoneal tuberculosis. (authors)

40 CFR 86.238-94-86.239-94 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false [Reserved] 86.238-94-86.239-94 Section 86.238-94-86.239-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures §§ 86.238-94—86.239-94 [Reserved] ...

40 CFR 86.233-94-86.234-94 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false [Reserved] 86.233-94-86.234-94 Section 86.233-94-86.234-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures §§ 86.233-94—86.234-94 [Reserved] ...

MR imaging versus PET/CT for evaluation of pancreatic lesions

Energy Technology Data Exchange (ETDEWEB)

Belião, Sara, E-mail: sara.beliao@clix.pt [Department of Radiology Hospital S. Francisco Xavier, Estrada do Forte do Alto do Duque, 1495-005 Lisbon (Portugal); Ferreira, Alexandra, E-mail: alexandratavaresferreira@gmail.com [Department of Radiology, Hospital D. Estefânia, Rua Jacinta Marto, 1169-045 Lisbon (Portugal); Vierasu, Irina, E-mail: Ortansa-Irina.Vierasu@ulb.ac.be [Service de Médecine Nucléaire, Route de Lennik 808, 1070 Brussels (Belgium); Blocklet, Didier, E-mail: dblockle@ulb.ac.be [Service de Médecine Nucléaire, Route de Lennik 808, 1070 Brussels (Belgium); Goldman, Serge, E-mail: petscan@ulb.ac.be [Service de Médecine Nucléaire, Route de Lennik 808, 1070 Brussels (Belgium); Metens, Thierry, E-mail: tmetens@ulb.ac.be [Service de Radiologie – Imagerie par Resonance Magnétique, Route de Lennik 808, 1070 Brussels (Belgium); Matos, Celso, E-mail: cmatos@ulb.ac.be [Service de Radiologie – Imagerie par Resonance Magnétique, Route de Lennik 808, 1070 Brussels (Belgium)

2012-10-15

Purpose: To retrospectively determine the diagnostic accuracy of magnetic resonance imaging (MRI) and combined positron emission tomography/computed tomography (PET/CT) in the differential diagnosis of benign and malignant pancreatic lesions. Materials and methods: Twenty-seven patients (15 women/12 men, mean age 56.5 years) with MR imaging and PET/CT studies performed to differentiate benign and malignant pancreatic lesions were identified between October 2008 and October 2010. Both MR and PET/CT data sets were retrospectively and blindly evaluated by two independent readers (4 readers total) with different degrees of experience, using a visual five-point score system. The results were correlated with final diagnosis obtained by histopathology. Results: 17 patients had malignant diseases and 10 patients had benign diseases. Depending on the observer, the sensitivity, specificity, positive predictive value and negative predictive value of MRI varied between 88–94%, 50–80%, 75–89% and 71–89% respectively. Sensitivities, specificities, positive predictive values and negative predictive values of PET/CT were 73%, 56%, 73% and 56% respectively. The diagnostic accuracy of MR for the differential diagnosis of pancreatic lesions was 74–89%, compared with 67% for PET/CT. The weighted Cohen's kappa coefficient was 0.47 at MR and 0.53 at PET/CT. Conclusion: MRI achieved higher sensitivity and specificity in the differential diagnosis of pancreatic lesions.

Assessing the role of {sup 18}F-FDG PET and {sup 18}F-FDG PET/CT in the diagnosis of soft tissue musculoskeletal malignancies: a systematic review and meta-analysis

Energy Technology Data Exchange (ETDEWEB)

Etchebehere, Elba C. [The University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Sirio Libanes Hospital, Department of Nuclear Medicine, Sao Paulo (Brazil); Hobbs, Brian P.; Milton, Denai R. [The University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States); Malawi, Osama [The University of Texas MD Anderson Cancer Center, Department of Imaging Physics, Houston, TX (United States); Patel, Shreyaskumar; Benjamin, Robert S. [The University of Texas MD Anderson Cancer Center, Department of Sarcoma Medical Oncology, Houston, TX (United States); Macapinlac, Homer A. [The University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States)

2016-05-15

Twelve years ago a meta-analysis evaluated the diagnostic performance of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in assessing musculoskeletal soft tissue lesions (MsSTL). Currently, PET/CT has substituted PET imaging; however, there has not been any published meta-analysis on the use of PET/CT or a comparison of PET/CT with PET in the diagnosis of MsSTL. Therefore, we conducted a meta-analysis to identify the current diagnostic performance of {sup 18}F-FDG PET/CT and determine if there is added value when compared to PET. A systematic review of English articles was conducted, and MEDLINE PubMed, the Cochrane Library, and Embase were searched from 1996 to March 2015. Studies exploring the diagnostic accuracy of {sup 18}F-FDG PET/CT (or dedicated PET) compared to histopathology in patients with MsSTL undergoing investigation for malignancy were included. Our meta-analysis included 14 articles composed of 755 patients with 757 soft tissue lesions. There were 451 (60 %) malignant tumors and 306 benign lesions. The {sup 18}F-FDG PET/CT (and dedicated PET) mean sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for diagnosing MsSTL were 0.96 (0.90, 1.00), 0.77 (0.67, 0.86), 0.88 (0.85, 0.91), 0.86 (0.78, 0.94), and 0.91 (0.83, 0.99), respectively. The posterior mean (95 % highest posterior density interval) for the AUC was 0.92 (0.88, 0.96). PET/CT had higher specificity, accuracy, and positive predictive value when compared to a dedicated PET (0.85, 0.89, and 0.91 vs 0.71, 0.85, and 0.82, respectively). {sup 18}F-FDG PET/CT and dedicated PET are both highly accurate in the diagnosis of MsSTL. PET/CT is more accurate and specific and has a higher positive predictive value than PET. (orig.)

Fully automated deformable registration of breast DCE-MRI and PET/CT

Science.gov (United States)

Dmitriev, I. D.; Loo, C. E.; Vogel, W. V.; Pengel, K. E.; Gilhuijs, K. G. A.

2013-02-01

Accurate characterization of breast tumors is important for the appropriate selection of therapy and monitoring of the response. For this purpose breast imaging and tissue biopsy are important aspects. In this study, a fully automated method for deformable registration of DCE-MRI and PET/CT of the breast is presented. The registration is performed using the CT component of the PET/CT and the pre-contrast T1-weighted non-fat suppressed MRI. Comparable patient setup protocols were used during the MRI and PET examinations in order to avoid having to make assumptions of biomedical properties of the breast during and after the application of chemotherapy. The registration uses a multi-resolution approach to speed up the process and to minimize the probability of converging to local minima. The validation was performed on 140 breasts (70 patients). From a total number of registration cases, 94.2% of the breasts were aligned within 4.0 mm accuracy (1 PET voxel). Fused information may be beneficial to obtain representative biopsy samples, which in turn will benefit the treatment of the patient.

Comparison of PET/CT with Sequential PET/MRI Using an MR-Compatible Mobile PET System.

Science.gov (United States)

Nakamoto, Ryusuke; Nakamoto, Yuji; Ishimori, Takayoshi; Fushimi, Yasutaka; Kido, Aki; Togashi, Kaori

2018-05-01

The current study tested a newly developed flexible PET (fxPET) scanner prototype. This fxPET system involves dual arc-shaped detectors based on silicon photomultipliers that are designed to fit existing MRI devices, allowing us to obtain fused PET and MR images by sequential PET and MR scanning. This prospective study sought to evaluate the image quality, lesion detection rate, and quantitative values of fxPET in comparison with conventional whole-body (WB) PET and to assess the accuracy of registration. Methods: Seventeen patients with suspected or known malignant tumors were analyzed. Approximately 1 h after intravenous injection of 18 F-FDG, WB PET/CT was performed, followed by fxPET and MRI. For reconstruction of fxPET images, MRI-based attenuation correction was applied. The quality of fxPET images was visually assessed, and the number of detected lesions was compared between the 2 imaging methods. SUV max and maximum average SUV within a 1 cm 3 spheric volume (SUV peak ) of lesions were also compared. In addition, the magnitude of misregistration between fxPET and MR images was evaluated. Results: The image quality of fxPET was acceptable for diagnosis of malignant tumors. There was no significant difference in detectability of malignant lesions between fxPET and WB PET ( P > 0.05). However, the fxPET system did not exhibit superior performance to the WB PET system. There were strong positive correlations between the 2 imaging modalities in SUV max (ρ = 0.88) and SUV peak (ρ = 0.81). SUV max and SUV peak measured with fxPET were approximately 1.1-fold greater than measured with WB PET. The average misregistration between fxPET and MR images was 5.5 ± 3.4 mm. Conclusion: Our preliminary data indicate that running an fxPET scanner near an existing MRI system provides visually and quantitatively acceptable fused PET/MR images for diagnosis of malignant lesions. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

States in 94Zr from 94Zr(d,d')94Zr* at 15.5 Mev

International Nuclear Information System (INIS)

Frota-Pessoa, E.; Joffily, S.

1986-01-01

94 energy levels up to approx. 4.3 Mev excitation energy are studied in the 94 Zr(d,d') 94 Zr* reaction. Deuterons had a bombarding energy of 15.5 MeV. The emergent deuterons were analysed by a magnetic spectrograph and the detector was nuclear emulsion. The resolution in energy was about 11 KeV. The distorted-wave analysis was used to determine the l transferred, the β 2 l and J Π values for some 94 Zr excited states. These results are compared with previous ones. 32 levels of excitation energy in 94 Zr were found which did not appear in previous 94 Zr(d,d') reactions. 20 levels do not correspond to the ones. (Author) [pt

Comparison between PET/MR and PET/CT in evaluation of oncological patients%PET/MR与PET/CT的对比研究

Institute of Scientific and Technical Information of China (English)

徐白萱; 富丽萍; 关志伟; 尹大一; 刘家金; 杨晖; 张锦明; 陈英茂; 安宁豫

2014-01-01

Objective To verify the feasibility of the integrated PET/MR for oncological applications by comparing PET/MR with PET/CT in terms of lesion detection and quantitative measurement.Methods A total of 277 patients (165 males,112 females,average age (52.9± 12.6) years) voluntarily participated in this same-day PET/CT and PET/MR comparative study.The time interval between the two studies was 15-35 min.PET/CT images were acquired and reconstructed following standard protocols.PET/MR covered the body trunk with a sequence combination of transverse T1 weighted imaging (WI) 3D-volumetric interpolated breath-hold,T2WI turbo spin echo with fat saturation,diffusion-weighted imaging,and simultaneous PET acquisition.PET images were reconstructed by vender-provided attenuation correction methods.The results of PET/CT and PET/MR were regarded as positive if any modality (CT,PET or MRI) was positive.SUVmax was obtained by the manually drawn ROI.Detection rates were compared with x2 test and SUVmax from the two modalities was analyzed with Spearman correlation analysis.Results A total of 353 lesions were detected in 220 patients.Compared to PET/CT,PET/MR revealed 30 additional true-positive lesions,while missed 6.The detection rates between PET/CT and PET/MR were significantly different (P＜0.05).The lesion-based and patient-based consistency was 89.8％ (317/353) and 85.9％ (189/220),respectively.There were significant correlations of SUVmax between PET/MR and PET/CT for lesions(rs =0.91,P＜0.01) and for normal tissues(rs =0.62-0.76,all P＜0.01).Conclusions With reference to PET/CT,integrated PET/MR may provide comparable semi-quantitative measurements of pathological lesions as well as normal tissues.Integrated PET/MR may be more effective to detect lesions in abdomen and pelvis.%目的 通过与PET/CT在病灶检测及定量分析方面的比较,论证PET/MR一体机应用于临床的可行性.方法 2012年5月至2013年2月共300例患者同天间隔15 ～ 35 min行PET/CT和PET

Pet Problems at Home: Pet Problems in the Community.

Science.gov (United States)

Soltow, Willow

1984-01-01

Discusses problems of pets in the community, examining the community's role related to disruptive pets and pet overpopulation. Also discusses pet problems at home, offering advice on selecting a pet, meeting a pet's needs, and disciplining pets. Includes a list of books, films/filmstrips, teaching materials, and various instructional strategies.…

18F-DG PET/CT in detection of recurrence and metastasis of colorectal cancer

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

AIM: To evaluate the value of 18F-DG PET/CT in detecting recurrence and/or metastasis of colorectal cancer (CRC).METHODS: Combined visual analysis with semiquantitative analysis, the 18F-DG PET/CT wholebody imaging results and the corresponding clinical data of 68 postoperative CRC patients including 48 male and 20 female with average age of 58.1 were analyzed retrospectively.RESULTS: Recurrence and/or metastasis were confirmed in 56 patients in the clinical follow-up after the PET/CT imaging. The sensitivity of PET/CT diagnosis of CRC recurrence and/or metastasis was 94.6%, and the specificity was 83.3%. The positive predictive value (PPV)was 96.4% and the negative predictive value (NPV) was 76.9%. PET/CT imaging detected one or more occult malignant lesions in 8 cases where abdominal/pelvic CT and/or ultrasonography showed negative findings, and also detected more lesions than CT or ultrasonography did in 30.4% (17/56) cases. Recurrence and/or metastasis was detected in 91.7% (22/24) cases with elevated serum CEA levels by 18F-DG PET/CT imaging.CONCLUSION: 18F-DG PET/CT could detect the recurrence and/or metastasis of CRC with high sensitivity and specificity.

Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests

OpenAIRE

Mustafa Demir; Türkay Toklu; Mohammad Abuqbeitah; Hüseyin Çetin; H. Sezer Sezgin; Nami Yeyin; Kerim Sönmezoğlu

2018-01-01

Objective: The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. Methods: According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated...

Evaluation of PET Scanner Performance in PET/MR and PET/CT Systems: NEMA Tests

OpenAIRE

Demir, Mustafa; Toklu, Türkay; Abuqbeitah, Mohammad; Çetin, Hüseyin; Sezgin, H. Sezer; Yeyin, Nami; Sönmezoğlu, Kerim

2018-01-01

Objective: The aim of the present study was to compare the performance of positron emission tomography (PET) component of PET/computed tomography (CT) with new emerging PET/magnetic resonance (MR) of the same vendor. Methods: According to National Electrical Manufacturers Association NU2-07, five separate experimental tests were performed to evaluate the performance of PET scanner of General Electric GE company; SIGNATM model PET/MR and GE Discovery 710 model PET/CT. The main investigated asp...

Clinical efficacy of FDG-PET scan as preoperative diagnostic tool in cervical cancer stage Ib and IIa: comparison between the results of FDG-PET scan and operative findings

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Hoon

1999-12-01

This study was done to evaluate the clinical feasibility of FDG-PET scan for routine preoperative diagnostic methods in cervical carcinoma. PET-scans were performed from March, 1999 to November, 1999. There were 6 stage Ib and 7 IIa patients and all patients were performed radical hysterectomy and bilateral pelvic lymph node dissections and were evaluated by FDG-PET scan before operation. The mean age of the patients were 50.3 years old. Six cases had lymph node metastases by pelvis MRI, and three cases by FDG-PET scan. We could not find any lymph node metastases at surgery in 3 patients (50.0%) among 6 patients who were diagnosed by nodal metastases by pelvis MRI. And we found 1 patients with nodal metastases who had negative findings by pelvis MRI. By FDG-PET scan, we could find metastases in all positive patients. But we also found 2 additional metastatic cases in the patients with negative findings. In this study, the comparison was very difficult due to the individual differences in the comparison would be made by site-specific not person. The sensitivity of MRI and FDG-PET scan were 50.0% and 30.0%. The specificity were 94.1 % and 95.6%. The positive predictive value were 55.6 % and 50.0 %. In conclusion, we could find any superiority of FDG-PET scan in the diagnosis of lymph node metastases the pelvis MRI. So there are limitations to use the FDG-PET scan in the routine preoperative diagnostic tools in cervical cancer. But if we have more experiences to use the FDG-PET scan such as precise cut-off value of SUV and combination of other imaging technique, the FDG-PET scan are still promising diagnostic tools in cervical cancer.

Harmonizing SUVs in multicentre trials when using different generation PET systems: prospective validation in non-small cell lung cancer patients

Energy Technology Data Exchange (ETDEWEB)

Lasnon, Charline; Quak, Elske [Francois Baclesse Cancer Centre, Nuclear Medicine Department, Caen (France); Desmonts, Cedric [Caen University Hospital, Nuclear Medicine Department, Caen (France); Gervais, Radj; Do, Pascal; Dubos-Arvis, Catherine [Francois Baclesse Cancer Centre, Thoracic Oncology, Caen (France); Aide, Nicolas [Francois Baclesse Cancer Centre, Nuclear Medicine Department, Caen (France); Centre Francois Baclesse, Service de Medecine Nucleaire, Caen cedex 5 (France)

2013-07-15

We prospectively evaluated whether a strategy using point spread function (PSF) reconstruction for both diagnostic and quantitative analysis in non-small cell lung cancer (NSCLC) patients meets the European Association of Nuclear Medicine (EANM) guidelines for harmonization of quantitative values. The NEMA NU-2 phantom was used to determine the optimal filter to apply to PSF-reconstructed images in order to obtain recovery coefficients (RCs) fulfilling the EANM guidelines for tumour positron emission tomography (PET) imaging (PSF{sub EANM}). PET data of 52 consecutive NSCLC patients were reconstructed with unfiltered PSF reconstruction (PSF{sub allpass}), PSF{sub EANM} and with a conventional ordered subset expectation maximization (OSEM) algorithm known to meet EANM guidelines. To mimic a situation in which a patient would undergo pre- and post-therapy PET scans on different generation PET systems, standardized uptake values (SUVs) for OSEM reconstruction were compared to SUVs for PSF{sub EANM} and PSF{sub allpass} reconstruction. Overall, in 195 lesions, Bland-Altman analysis demonstrated that the mean ratio between PSF{sub EANM} and OSEM data was 1.03 [95 % confidence interval (CI) 0.94-1.12] and 1.02 (95 % CI 0.90-1.14) for SUV{sub max} and SUV{sub mean}, respectively. No difference was noticed when analysing lesions based on their size and location or on patient body habitus and image noise. Ten patients (84 lesions) underwent two PET scans for response monitoring. Using the European Organization for Research and Treatment of Cancer (EORTC) criteria, there was an almost perfect agreement between OSEM{sub PET1}/OSEM{sub PET2} (current standard) and OSEM{sub PET1}/PSF{sub EANM-PET2} or PSF{sub EANM-PET1}/OSEM{sub PET2} with kappa values of 0.95 (95 % CI 0.91-1.00) and 0.99 (95 % CI 0.96-1.00), respectively. The use of PSF{sub allpass} either for pre- or post-treatment (i.e. OSEM{sub PET1}/PSF{sub allpass-PET2} or PSF{sub allpass-PET1}/OSEM{sub PET2}) showed

The impact of PET/CT on the management of hepatic and extra hepatic metastases from gastrointestinal cancers

Energy Technology Data Exchange (ETDEWEB)

Polat, Erdal, E-mail: erdal066@yahoo.com [Kartal Kosuyolu High Specialty Training and Research Hospital, Department of Gastrointestinal Surgery, Istanbul (Turkey); Bostanci, Erdal Birol [Sakarya University, Faculty of Medicine, Department of General Surgery, Sakarya (Turkey); Aksoy, Erol [Turkiye Yuksek Ihtisas Teaching and Research Hospital, Department of Gastroenterological Surgery, Ankara (Turkey); Karaman, Kerem [Sakarya University, Faculty of Medicine, Department of General Surgery, Sakarya (Turkey); Poyraz, Nilufer Yildirim [Ataturk Teaching and Research Hospital, Department of Nuclear Medicine, Ankara (Turkey); Duman, Ugur [Sevket Yilmaz Training and Research Hospital, Department of General Surgery, Bursa (Turkey); Gencturk, Zeynep Biyikli [Ankara University, Faculty of Medicine, Department of Biostatistics, Ankara (Turkey); Yol, Sinan [Medeniyet University, Faculty of Medicine, Department of General surgery, Istanbul (Turkey)

2015-06-15

Highlights: • CT is more sensitive than PET/CT in detecting hepatic metastases. • PET/CT is more specific in detecting hepatic metastases. • CT and PET/CT have equal sensitivity in detecting extra hepatic metastases. • PET/CT is more specific in detecting extra hepatic metastases. • PET/CT has an impact of about 40% on changing the management strategies. - Abstract: Purpose: To investigate the efficacy of positron emission tomography/computed tomography (PET/CT) in detection and management of hepatic and extrahepatic metastases from gastrointestinal cancers. Materials and methods: Between February 2008 and July 2010, patients histopathologically diagnosed with gastrointestinal cancer and showing suspected metastasis on CT screening were subsequently evaluated with PET/CT. All patients were subgrouped according to histopathological origin and localization of the primary tumor. Localization of gastrointestinal cancers was further specified as lower gastrointestinal system (GIS), upper GIS, or hepato-pancreato-biliary (HPB). Both accuracy and impact of CT and PET/CT on patient management were retrospectively evaluated. Results: One hundred and thirteen patients diagnosed histopathologically with gastrointestinal cancers were retrospectively evaluated. Seventy-nine patients had adenocarcinoma and 34 patients other gastrointestinal tumors. Forty-one patients were in the upper GIS group, 30 patients in the HPB group, and 42 patients in the lower GIS group. Evaluation the diagnostic performance of PET/CT for suspected metastasis according to histopathological origin of the tumor, revealed that the sensitivity of PET/CT – although statistically not different – was higher in adenocarcinomas than in non-adenocarcinomas (90% (95% CI, 0.78–0.96) vs. 71.4% (95% CI, 0.45–0.88), P = 0.86). The specificity was not significantly different (85.7% (95% CI, 0.70–0.93) vs. 85% (95% CI, 0.63–0.94), P = 1.00). In the overall patient group; CT was significantly more

Diagnostic usefulness of 18F-FAMT PET and L-type amino acid transporter 1 (LAT1) expression in oral squamous cell carcinoma

International Nuclear Information System (INIS)

Nobusawa, Aiko; Kim, Mai; Kaira, Kyoichi; Miyashita, Go; Negishi, Akihide; Yokoo, Satoshi; Oriuchi, Noboru; Higuchi, Tetsuya; Tsushima, Yoshito; Kanai, Yoshikatsu; Oyama, Tetsunari

2013-01-01

l-[3- 18 F]-α-Methyltyrosine ( 18 F-FAMT) was developed as an amino acid tracer for PET imaging to provide better specificity than 2-[ 18 F]fluoro-2-deoxy-d-glucose ( 18 F-FDG) PET for cancer diagnosis. We investigated the diagnostic usefulness of 18 F-FAMT in oral squamous cell carcinoma (OSCC). The correlation between tumour uptake of 18 F-FAMT and L-type amino acid transporter 1 (LAT1) expression was determined. The study group comprised 68 OSCC patients who underwent both 18 F-FAMT and 18 F-FDG PET. Resected tumour sections were stained by immunohistochemistry for LAT1, CD98 and Ki-67, and microvessel density was determined in terms of CD34 and p53 expression. The sensitivity of primary tumour detection by 18 F-FAMT and 18 F-FDG PET was 98 % and 100 %, respectively. The sensitivity, specificity and accuracy of 18 F-FAMT PET for detecting malignant lymph nodes were 68 %, 99 % and 97 %, respectively, and equivalent values for 18 F-FDG PET were 84 %, 94 % and 94 %, respectively. The specificity and accuracy of 18 F-FAMT were significantly higher than those of 18 F-FDG. The uptake of 18 F-FAMT was significantly correlated with LAT1 expression, cell proliferation and advanced stage. The expression of LAT1 in OSCC cells was closely correlated with CD98 levels, cell proliferation and angiogenesis. 18 F-FAMT PET showed higher specificity for detecting malignant lesions than 18 F-FDG PET. The uptake of 18 F-FAMT by OSCC cells can be determined by the presence of LAT1 expression and tumour cell proliferation. (orig.)

Comparison of lesion detection and quantitation of tracer uptake between PET from a simultaneously acquiring whole-body PET/MR hybrid scanner and PET from PET/CT

International Nuclear Information System (INIS)

Wiesmueller, Marco; Schmidt, Daniela; Beck, Michael; Kuwert, Torsten; Gall, Carl C. von; Quick, Harald H.; Navalpakkam, Bharath; Lell, Michael M.; Uder, Michael; Ritt, Philipp

2013-01-01

PET/MR hybrid scanners have recently been introduced, but not yet validated. The aim of this study was to compare the PET components of a PET/CT hybrid system and of a simultaneous whole-body PET/MR hybrid system with regard to reproducibility of lesion detection and quantitation of tracer uptake. A total of 46 patients underwent a whole-body PET/CT scan 1 h after injection and an average of 88 min later a second scan using a hybrid PET/MR system. The radioactive tracers used were 18 F-deoxyglucose (FDG), 18 F-ethylcholine (FEC) and 68 Ga-DOTATATE (Ga-DOTATATE). The PET images from PET/CT (PET CT ) and from PET/MR (PET MR ) were analysed for tracer-positive lesions. Regional tracer uptake in these foci was quantified using volumes of interest, and maximal and average standardized uptake values (SUV max and SUV avg , respectively) were calculated. Of the 46 patients, 43 were eligible for comparison and statistical analysis. All lesions except one identified by PET CT were identified by PET MR (99.2 %). In 38 patients (88.4 %), the same number of foci were identified by PET CT and by PET MR . In four patients, more lesions were identified by PET MR than by PET CT , in one patient PET CT revealed an additional focus compared to PET MR . The mean SUV max and SUV avg of all lesions determined by PET MR were by 21 % and 11 % lower, respectively, than the values determined by PET CT (p CT and PET MR were minor, but statistically significant. Nevertheless, a more detailed study of the quantitative accuracy of PET MR and the factors governing it is needed to ultimately assess its accuracy in measuring tissue tracer concentrations. (orig.)

The diagnostic value of PET-CT on peripheral lung cancer

International Nuclear Information System (INIS)

Li Lebao; Peng Xiang; Ye Hui; Mo Yi; Xie Aimin

2010-01-01

Objective: To evaluate the value of PET-CT in the diagnosis of peripheral lung cancer. cancer proved pathology characteristics and standardized uptake value (SUV) of 70 patients with lung cancer proved by pathology were analyzed retrospectively. Results: Of the 70 cases, 32 cases were squamous carcinoma, 25 cases were adenocarcinoma, 8 cases were small cell lung cancer, 3 cases were adenosquamous carcinoma and 2 cases were megacell lung cancer. The average SUV of the lung cancer was 4.94±1.53. In the group of lung cancer, hypermetabolic lesions were found in 66 cases and the SUV was more than 2.5 while the SUV was less than 2.5 in 4 cases. Positive correlation was showed in the SUV and the size of tumors. Conclusions: The peripheral lung cancer has its special imaging appearances of PET-CT. PET-CT is an excellent modality in the diagnosis and differential diagnosis of preipheral lung cancer. The SUV combining with morphological findings sometimes may be helpful for the differential diagnosis. (authors)

33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York. 100.124 Section 100.124 Navigation and Navigable... NAVIGABLE WATERS § 100.124 Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York...

Detection of Cancer with PET and PET/CT in Asymptomatic Volunteers

International Nuclear Information System (INIS)

Chung, Ji In; Choi, Joon Young; Lee, Kyung Han; Kim, Byung Tae; Choi, Yoon Ho; Cho, Han Byoul; Shim, Jae Yong

2009-01-01

We retrospectively investigated the diagnostic performance of 18 F-fluorodeoxyglucose positron emission tomography (PET) and PET/CT for cancer detection in asymptomatic health-check examinees. This study consisted of 5091 PET or PET/CT conducted as part of annual health examination at one hospital from March 1998 to February 2008. To find the incidence of cancers, medical records of the subjects were thoroughly reviewed for a follow-up period of one year. The patterns of formal readings of PET and PET/CT were analyzed to assess the sensitivity and specificity for cancer detection. The histopathology and stage of the cancers were evaluated in relation to the results of PET. Eighty-six cancers (1.7%) were diagnosed within one year after PET or PET/CT. When PET and PET/CT results were combined, the sensitivity was 48.8% and specificity was 81.1% for cancer detection. PET only had a sensitivity of 46.2% and a specificity of 81.4%, and PET/CT only had a sensitivity of 75.0% and a specificity of 78.5% respectively. There were no significant differences in cancer site, stage and histopathology between PET positive and PET negative cancers. In 19.3% of formal readings of PET and PET/CT, further evaluation to exclude malignancy or significant disease was recommended. Head and neck area and upper gastrointestinal tract were commonly recommended sites for further evaluation. PET and PET/CT showed moderate performance for detecting cancers in asymptomatic adults in this study. More experience and further investigation are needed to overcome limitations of PET and PET/CT for cancer screening

Assess results of PET/CT in cancer diagnosis, follow up treatment and simulation for radiation therapy

International Nuclear Information System (INIS)

Mai Trong Khoa; Tran Dinh Ha; Tran Hai Binh

2015-01-01

PET/CT (Positron Emission Computed Tomography) has been studied and established as routine at the Nuclear Medicine and Oncology Center, Bach Mai hospital. From 8/2009 to 5/2015, 6223 patients have been undergone PET/CT scan. Among them, diagnostic and simulation PET/CT scan for cancer patients accounted to 5833 (93.8%). Researches about value of PET/CT for most common cancers have been done. Results: PET/CT can help the primary tumor diagnosis, metastases detection, staging, simulation for radiation therapy, response to treatment assessment, and relapses after treatment identification. Percentage accordance between PET / CT and histopathology was 96% (esophagus cancer), 94.7% (lung cancer). Average maxSUV value of primary tumor of the esophagus cancer, colorectal cancer, nasopharynx cancer, lung cancer, and NHL respectively 9.50, 9.78, 11.08, 9.17, 10.21. MaxSUV value increased with histological grade and tumor size. After undergone PET / CT, stage of disease changed in 28% esophagus cancer; 22.7% colorectal cancer; stage of disease increased in 23.5% of NHL, 32.0% of lung cancer, and 25.0% of nasopharynx cancer. PET / CT simulation for radiation therapy target volume reduced in 28% of nasopharynx cancer, which helped the radioactive dose concentrate exactly in the target lesions, minimize effect to healthy tissues, improved the effectiveness of treatment and reduced complications. (author)

PET

DEFF Research Database (Denmark)

Mariager, Rasmus Mølgaard; Schmidt, Regin; Heiberg, Morten Rievers

PET handler om den hemmelige tjenestes arbejde under den kolde krig 1945-1989. Her fortæller Regin Schmidt, Rasmus Mariager og Morten Heiberg om de mest dramatiske og interessante sager fra PET's arkiv. PET er på flere måder en udemokratisk institution, der er sat til at vogte over demokratiet....... Dens virksomhed er skjult for offentligheden, den overvåger borgernes aktiviteter, og den registrerer følsomme personoplysninger. Historien om PET rejser spørgsmålet om, hvad man skal gøre, når befolkningen i et demokrati er kritisk indstillet over for overvågningen af lovlige politiske aktiviteter......, mens myndighederne mener, at det er nødvendigt for at beskytte demokratiet. PET er på en gang en fortælling om konkrete aktioner og begivenheder i PET's arbejde og et stykke Danmarkshistorie. Det handler om overvågning, spioner, politisk ekstremisme og international terrorisme.  ...

Usefulness of 18F fluoride PET/CT in breast cancer patients with osteosclerotic bone metastases

International Nuclear Information System (INIS)

Yoon, Seok Ho; Kim, Ku Sang; Kang, Seok Yun; Song, Hee Sung; Jo, Kyung Sook; Lee, Su Jin; Yoon, Joon Kee; An, Young Sil; Choi, Bong Hoi

2012-01-01

Bone metastasis is an important factor for the treatment and prognosis of breast cancer patients. Whole body bone scintigraphy (WBBS) can evaluate skeletal metastases, and 18 F FDG PET/CT seems to exhibit high specificity and accuracy in detecting bone metastases. However, there is a limitation of 18 F FDG PET in assessing sclerotic bone metastases because some lesions may be undetectable. Recent studies showed that 18 F fluoride PET/CT is more sensitive than WBBS in detecting bone metastases. This study aims to evaluate the usefulness of 18 F fluoride PET/CT by comparing it with WBBS and 18 F FDG PET/CT in breast cancer patients with osteosclerotic skeletal metastases. Nine breast cancer patients with suspected bone metastases (9 females; mean age ± SD, 55.6±10.0 years) underwent 99m Tc MDP WBBS, 18 F FDG PET/CT and 18 F fluoride PET/CT. Lesion based analysis of five regions of the skeletons(skull, vertebral column, thoracic cage, pelvic bones and long bones of extremities) and patient based analysis were performed. 18 F fluoride PET/CT, 18 F FDG PET/CT and WBBS detected 49, 20 and 25 true metastases, respectively. Sensitivity, specificity, positive predictive value and negative predictive value of 18 F fluoride PET/CT were 94.2%, 46.3%, 57.7% and 91.2%, respectively. Most true metastatic lesions of 18 F fluoride PET/CT had osteosclerotic change (45/49, 91.8%), and only four lesions showed osteolytic change. Most lesions on 18 F FDG PET/CT also demonstrated osteosclerotic change (17/20, 85.0%) with three osteolytic lesions. All true metastatic lesions detected on WBBS and 18 F FDG PET/CT were identified on 18 F fluoride PET/CT. 18 F FDG PET/CT in detecting osteosclerotic metastatic lesions. 18 F fluoride PET/CT might be useful in evaluating osteosclerotic metastases in breast cancer patients

A feasibility study of a PET/MRI insert detector using strip-line and waveform sampling data acquisition.

Science.gov (United States)

Kim, H; Chen, C-T; Eclov, N; Ronzhin, A; Murat, P; Ramberg, E; Los, S; Wyrwicz, Alice M; Li, Limin; Kao, C-M

2015-06-01

We are developing a time-of-flight Positron Emission Tomography (PET) detector by using silicon photo-multipliers (SiPM) on a strip-line and high speed waveform sampling data acquisition. In this design, multiple SiPMs are connected on a single strip-line and signal waveforms on the strip-line are sampled at two ends of the strip to reduce readout channels while fully exploiting the fast time response of SiPMs. In addition to the deposited energy and time information, the position of the hit SiPM along the strip-line is determined by the arrival time difference of the waveform. Due to the insensitivity of the SiPMs to magnetic fields and the compact front-end electronics, the detector approach is highly attractive for developing a PET insert system for a magnetic resonance imaging (MRI) scanner to provide simultaneous PET/MR imaging. To investigate the feasibility, experimental tests using prototype detector modules have been conducted inside a 9.4 Tesla small animal MRI scanner (Bruker BioSpec 94/30 imaging spectrometer). On the prototype strip-line board, 16 SiPMs (5.2 mm pitch) are installed on two strip-lines and coupled to 2 × 8 LYSO scintillators (5.0 × 5.0 × 10.0 mm 3 with 5.2 mm pitch). The outputs of the strip-line boards are connected to a Domino-Ring-Sampler (DRS4) evaluation board for waveform sampling. Preliminary experimental results show that the effect of interference on the MRI image due to the PET detector is negligible and that PET detector performance is comparable with the results measured outside the MRI scanner.

Clinical usefulness of PET in the management of oral cancer. Comparison between FDG-PET and MET-PET

International Nuclear Information System (INIS)

Kitagawa, Yoshimasa; Saitoh, Masaaki; Nakamura, Mikiko

2007-01-01

Inductive chemoradiotherapy has played an important role in preserving organs and functions in patients with oral squamous cell carcinoma (SCC). To determine whether a reduced form of surgery should be performed after chemoradiotherapy, accurate evaluation of residual tumor cells is essential. We investigated the clinical value of positron emission tomography with 18 F labeled fluorodeoxyglucose (FDG-PET) in the management of oral SCCs. Forty-five patients underwent two FDG-PET studies, one prior to and one at 6 weeks after the chemoradiotherapy. Pretreatment FDG-PET was useful in predicting the response to treatment. Posttreatment FDG-PET could evaluate residual viable cells and prognosis. Organ preservation may be feasible based on PET evaluation. Hence FDG-PET is a valuable tool in the treatment of oral cancer. 11 C-Methionine (MET) is another promising tracer for PET that can be used to assess metabolic demand for amino acids in cancer cells. A MET-PET and FDG-PET study was performed during the same period to investigate diagnostic accuracy in 40 oral malignancies. Sensitivity and positive predictive value of MET-PET were 95% and 100%, respectively, and were comparable with those of FDG-PET. Further study is required to determine the diagnostic significance of MET-PET in evaluating response to chemoradiotherapy. (author)

Clinical value of FDG PET/CT in the diagnosis of suspected recurrent ovarian cancer: is there an impact of FDG PET/CT on patient management?

International Nuclear Information System (INIS)

Bilici, Ahmet; Ustaalioglu, Bala Basak Oven; Seker, Mesut; Salepci, Taflan; Gumus, Mahmut; Canpolat, Nesrin; Tekinsoy, Bulent

2010-01-01

The aim of this study was to evaluate the clinical value of FDG PET/CT in patients with suspected ovarian cancer recurrence as compared with diagnostic CT, and to assess the impact of the results of FDG PET/CT on treatment planning. Included in this retrospective study were 60 patients with suspected recurrent ovarian cancer who had previously undergone primary debulking surgery and had been treated with adjuvant chemotherapy. Diagnostic CT and FDG PET/CT imaging were performed for all patients as clinically indicated. The changes in the clinical management of patients according to the results of FDG PET/CT were also analysed. FDG PET/CT was performed in 21 patients with a previously negative or indeterminate diagnostic CT scan, but an elevated CA-125 level, and provided a sensitivity of 95% in the detection of recurrent disease. FDG PET/CT revealed recurrent disease in 19 patients. In 17 of 60 patients, the indication for FDG PET/CT was an elevated CA-125 level and an abnormal diagnostic CT scan to localize accurately the extent of disease. FDG PET/CT scans correctly identified recurrent disease in 16 of the 17 patients, a sensitivity of 94.1%. Moreover, FDG PET/CT was performed in 18 patients with clinical symptoms of ovarian cancer recurrence, an abnormal diagnostic CT scan, but a normal CA-125 level. In this setting, FDG PET/CT correctly confirmed recurrent disease in seven patients providing a sensitivity of 100% in determining recurrence. In four patients, FDG PET/CT was carried out for the assessment of treatment response. Three of four scans were classified as true-negative indicating a complete response. In the other patient, FDG PET/CT identified progression of disease. In total, 45 (75%) of the 60 patients had recurrent disease, in 14 (31.1%) documented by histopathology and in 31 (68.9%) on clinical follow-up, while 15 (25%) had no evidence of recurrent disease. The overall sensitivity, specificity, accuracy, and positive and negative predictive value

Development of PET/MRI with insertable PET for simultaneous PET and MR imaging of human brain

International Nuclear Information System (INIS)

Jung, Jin Ho; Choi, Yong; Jung, Jiwoong; Kim, Sangsu; Lim, Hyun Keong; Im, Ki Chun; Oh, Chang Hyun; Park, Hyun-wook; Kim, Kyung Min; Kim, Jong Guk

2015-01-01

Purpose: The purpose of this study was to develop a dual-modality positron emission tomography (PET)/magnetic resonance imaging (MRI) with insertable PET for simultaneous PET and MR imaging of the human brain. Methods: The PET detector block was composed of a 4 × 4 matrix of detector modules, each consisting of a 4 × 4 array LYSO coupled to a 4 × 4 Geiger-mode avalanche photodiode (GAPD) array. The PET insert consisted of 18 detector blocks, circularly mounted on a custom-made plastic base to form a ring with an inner diameter of 390 mm and axial length of 60 mm. The PET gantry was shielded with gold-plated conductive fabric tapes with a thickness of 0.1 mm. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuit. The flat cables were shielded with a mesh-type aluminum sheet with a thickness of 0.24 mm. The position decoder circuit and field programmable gate array-embedded DAQ modules were enclosed in an aluminum box with a thickness of 10 mm and located at the rear of the MR bore inside the MRI room. A 3-T human MRI system with a Larmor frequency of 123.7 MHz and inner bore diameter of 60 cm was used as the PET/MRI hybrid system. A custom-made radio frequency (RF) coil with an inner diameter of 25 cm was fabricated. The PET was positioned between gradient and the RF coils. PET performance was measured outside and inside the MRI scanner using echo planar imaging, spin echo, turbo spin echo, and gradient echo sequences. MRI performance was also evaluated with and without the PET insert. The stability of the newly developed PET insert was evaluated and simultaneous PET and MR images of a brain phantom were acquired. Results: No significant degradation of the PET performance caused by MR was observed when the PET was operated using various MR imaging sequences. The signal-to-noise ratio of MR images was slightly degraded due to the PET insert installed inside the MR bore while the homogeneity was

Development of PET/MRI with insertable PET for simultaneous PET and MR imaging of human brain

Energy Technology Data Exchange (ETDEWEB)

Jung, Jin Ho; Choi, Yong, E-mail: ychoi.image@gmail.com; Jung, Jiwoong; Kim, Sangsu; Lim, Hyun Keong; Im, Ki Chun [Department of Electronic Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 121-742 (Korea, Republic of); Oh, Chang Hyun; Park, Hyun-wook [Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Kim, Kyung Min; Kim, Jong Guk [Korea Institute of Radiological and Medical Science, 75 Nowon-ro, Nowon-gu, Seoul 139-709 (Korea, Republic of)

2015-05-15

Purpose: The purpose of this study was to develop a dual-modality positron emission tomography (PET)/magnetic resonance imaging (MRI) with insertable PET for simultaneous PET and MR imaging of the human brain. Methods: The PET detector block was composed of a 4 × 4 matrix of detector modules, each consisting of a 4 × 4 array LYSO coupled to a 4 × 4 Geiger-mode avalanche photodiode (GAPD) array. The PET insert consisted of 18 detector blocks, circularly mounted on a custom-made plastic base to form a ring with an inner diameter of 390 mm and axial length of 60 mm. The PET gantry was shielded with gold-plated conductive fabric tapes with a thickness of 0.1 mm. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuit. The flat cables were shielded with a mesh-type aluminum sheet with a thickness of 0.24 mm. The position decoder circuit and field programmable gate array-embedded DAQ modules were enclosed in an aluminum box with a thickness of 10 mm and located at the rear of the MR bore inside the MRI room. A 3-T human MRI system with a Larmor frequency of 123.7 MHz and inner bore diameter of 60 cm was used as the PET/MRI hybrid system. A custom-made radio frequency (RF) coil with an inner diameter of 25 cm was fabricated. The PET was positioned between gradient and the RF coils. PET performance was measured outside and inside the MRI scanner using echo planar imaging, spin echo, turbo spin echo, and gradient echo sequences. MRI performance was also evaluated with and without the PET insert. The stability of the newly developed PET insert was evaluated and simultaneous PET and MR images of a brain phantom were acquired. Results: No significant degradation of the PET performance caused by MR was observed when the PET was operated using various MR imaging sequences. The signal-to-noise ratio of MR images was slightly degraded due to the PET insert installed inside the MR bore while the homogeneity was

Evaluation of attenuation correction in cardiac PET using PET/MR.

Science.gov (United States)

Lau, Jeffrey M C; Laforest, R; Sotoudeh, H; Nie, X; Sharma, S; McConathy, J; Novak, E; Priatna, A; Gropler, R J; Woodard, P K

2017-06-01

Simultaneous acquisition Positron emission tomography/magnetic resonance (PET/MR) is a new technology that has potential as a tool both in research and clinical diagnosis. However, cardiac PET acquisition has not yet been validated using MR imaging for attenuation correction (AC). The goal of this study is to evaluate the feasibility of PET imaging using a standard 2-point Dixon volume interpolated breathhold examination (VIBE) MR sequence for AC. Evaluation was performed in both phantom and patient data. A chest phantom containing heart, lungs, and a lesion insert was scanned by both PET/MR and PET/CT. In addition, 30 patients underwent whole-body 18 F-fluorodeoxyglucose PET/CT followed by simultaneous cardiac PET/MR. Phantom study showed 3% reduction of activity values in the myocardium due to the non-inclusion of the phased array coil in the AC. In patient scans, average standardized uptake values (SUVs) obtained by PET/CT and PET/MR showed no significant difference (n = 30, 4.6 ± 3.5 vs 4.7 ± 2.8, P = 0.47). There was excellent per patient correlation between the values acquired by PET/CT and PET/MR (R 2  = 0.97). Myocardial SUVs PET imaging using MR for AC shows excellent correlation with myocardial SUVs obtained by standard PET/CT imaging. The 2-point Dixon VIBE MR technique can be used for AC in simultaneous PET/MR data acquisition.

Sustainable development in the Hudson Bay/James Bay bioregion

International Nuclear Information System (INIS)

Anon.

1991-01-01

An overview is presented of projects planned for the James Bay/Hudson Bay region, and the expected environmental impacts of these projects. The watershed of James Bay and Hudson Bay covers well over one third of Canada, from southern Alberta to central Ontario to Baffin Island, as well as parts of north Dakota and Minnesota in the U.S.A. Hydroelectric power developments that change the timing and rate of flow of fresh water may cause changes in the nature and duration of ice cover, habitats of marine mammals, fish and migratory birds, currents into and out of Hudson Bay/James Bay, seasonal and annual loads of sediments and nutrients to marine ecosystems, and anadromous fish populations. Hydroelectric projects are proposed for the region by Quebec, Ontario and Manitoba. In January 1992, the Canadian Arctic Resources Committee (CARC), the Environmental Committee of Sanikuluaq, and the Rawson Academy of Arctic Science will launch the Hudson Bay/James Bay Bioregion Program, an independent initiative to apply an ecosystem approach to the region. Two main objectives are to provide a comprehensive assessment of the cumulative impacts of human activities on the marine and freshwater ecosystems of the Hudson Bay/James Bay bioregion, and to foster sustainable development by examining and proposing cooperative processes for decision making among governments, developers, aboriginal peoples and other stakeholders. 1 fig

Chronic Liver Disease and the Detection of Hepatocellular Carcinoma by [18F]fluorocholine PET/CT

Directory of Open Access Journals (Sweden)

Sandi A. Kwee

2015-05-01

Full Text Available Positron emission tomography (PET using the radiopharmaceutical tracer fluorine-18 fluorocholine (FCh can elucidate tumors based on differences in choline phospholipid metabolism between tumor and surrounding tissue. The feasibility of detecting hepatocellular carcinoma (HCC using FCh PET has been shown despite constitutively high parenchymal choline metabolism in the liver. Since HCC frequently develops in the setting of chronic liver disease, we comparatively evaluated FCh PET/CT between cirrhotic and non-cirrhotic patients with HCC to investigate the effects of hepatic dysfunction on tumor detection and the tumor-to-background ratio (TBR of FCh uptake. FCh PET/CT was performed prospectively in 22 consecutive patients with HCC (7 newly diagnosed, 15 previously treated. Of these 22 patients, 14 were cirrhotic and 8 non-cirrhotic. Standardized uptake value (SUV measurements were obtained by region of interest analysis of the PET images. Tumor FCh uptake and the TBR were compared between cirrhotic and non-cirrhotic patients. Liver lesions were confirmed to be HCC by biopsy in 10 patients and by Barcelona criteria in 4 patients. There was correspondingly increased liver tumor FCh uptake in 13/14 of those patients, and iso-intense tumor FCh uptake (TBR 0.94 in one non-cirrhotic patient with newly diagnosed HCC. FCh PET/CT also showed metastatic disease without local tumor recurrence in 2 previously treated patients, and was negative in 6 treated patients without tumor recurrence by radiographic and clinical follow-up. Tumor maximum SUV ranged from 6.4 to 15.3 (mean 12.1 and liver TBR ranged from 0.94 to 2.1 (mean 1.6, with no significant differences between cirrhotic and non-cirrhotic patients (SUVmax 11.9 vs. 12.2, p = 0.83; TBR 1.71 vs. 1.51, p = 0.29. Liver parenchyma mean SUV was significantly lower in cirrhotic patients (6.4 vs. 8.7, p < 0.05. This pilot study supports the general feasibility of HCC detection by FCh PET/CT. However, a broad

PET or PET-CT with cancer screening

International Nuclear Information System (INIS)

Wang Taisong; Zhao Jinhua; Song Jianhua

2007-01-01

At present, cancer screening remains a lot of debate in contemporary medical practice. Many constitutes have done a lot of experiments in cancer screening. The same version is that recommendations and decisions regarding cancer screening should be based on reliable data, not self- approbation. Now, some institutes advocate 18 F-FDG PET or 18 F-FDG PET-CT for cancer screening, here, discussed status quo, potential financial, radiation safety and statistical data in 18 F-FDG PET or 18 F-FDG PET- CT cancer screening. (authors)

PET / MRI vs. PET / CT. Indications Oncology

International Nuclear Information System (INIS)

Oliva González, Juan P.

2016-01-01

Hybrid techniques in Nuclear Medicine is currently a field in full development for diagnosis and treatment of various medical conditions. With the recent advent of PET / MRI much it speculated about whether or not it is superior to PET / CT especially in oncology. The Conference seeks to clarify this situation by dealing issues such as: State of the art technology PET / MRI; Indications Oncology; Some clinical cases. It concludes by explaining the oncological indications of both the real and current situation of the PET / MRI. (author)

FDG-PET and CT patterns of bone metastases and their relationship to previously administered anti-cancer therapy

International Nuclear Information System (INIS)

Israel, Ora; Bar-Shalom, Rachel; Keidar, Zohar; Goldberg, Anat; Nachtigal, Alicia; Militianu, Daniela; Fogelman, Ignac

2006-01-01

To assess 18 F-fluorodeoxyglucose (FDG) uptake in bone metastases in patients with and without previous treatment, and compare positive positron emission tomography (PET) with osteolytic or osteoblastic changes on computed tomography (CT). One hundred and thirty-one FDG-PET/CT studies were reviewed for bone metastases. A total of 294 lesions were found in 76 patients, 81 in untreated patients and 213 in previously treated patients. PET was assessed for abnormal FDG uptake localised by PET/CT to the skeleton. CT was evaluated for bone metastases and for blastic or lytic pattern. The relationship between the presence and pattern of bone metastases on PET and CT, and prior treatment was statistically analysed using the chi-square test. PET identified 174 (59%) metastases, while CT detected 280 (95%). FDG-avid metastases included 74/81 (91%) untreated and 100/213 (47%) treated lesions (p<0.001). On CT there were 76/81 (94%) untreated and 204/213 (96%) treated metastases (p NS). In untreated patients, 85% of lesions were seen on both PET and CT (26 blastic, 43 lytic). In treated patients, 53% of lesions were seen only on CT (95 blastic, 18 lytic). Of the osteoblastic metastases, 65/174 (37%) were PET positive and 98/120 (82%), PET negative (p<0.001). The results of the present study indicate that when imaging bone metastases, prior treatment can alter the relationship between PET and CT findings. Most untreated bone metastases are PET positive and lytic on CT, while in previously treated patients most lesions are PET negative and blastic on CT. PET and CT therefore appear to be complementary in the assessment of bone metastases. (orig.)

Application of PET and PET/CT imaging for cancer screening

International Nuclear Information System (INIS)

Chen Yenkung; Hu Fenglan; Shen Yehyou; Liao, A.C.; Hung, T.Z.; Su, Chentau; Chen Liangkuang

2004-01-01

The aim of this study was to evaluate the potential application of 18F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) and PET/CT for cancer screening in asymptomatic individuals. Methods: The subjects consisted of 3631 physical check up examinees (1947 men, 1684 women; mean age ±SD, 52.1±8.2 y) with non-specific medical histories. Whole-body FDG PET (or PET/CT), ultrasound and tumor markers were performed on all patients. Focal hypermetabolic areas with intensities equal to or exceeding the level of FDG uptake in the brain and bladder were considered abnormal and interpreted as neoplasia. Follow-up periods were longer than one year. Results: Among the 3631 FDG PET (including 1687 PET/CT), ultrasound and tumor markers examinations, malignant tumors were discovered in 47 examinees (1.29%). PET findings were true-positive in 38 of the 47 cancers (80.9%). In addition, 32 of the 47 cancers were performed with the PET-CT scan. PET detected cancer lesions in 28 of the 32 examinees. However, the CT detected cancer lesions in only 15 of 32 examinees. Conclusion: The sensitivity of FDG PET in the detection of a wide variety of cancers is high. Most cancer can be detected with FDG PET in a resectable stage. CT of the PET/CT for localization and characteristics of the lesion shows an increased specificity of the PET scan. Using ultrasound and tumor markers may complement the PET scan in cancer screening for hepatic and urologic neoplasms. (authors)

Diagnostic usefulness of {sup 18}F-FAMT PET and L-type amino acid transporter 1 (LAT1) expression in oral squamous cell carcinoma

Energy Technology Data Exchange (ETDEWEB)

Nobusawa, Aiko [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan); Kim, Mai [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Gunma University Graduate School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Maebashi, Gunma (Japan); Kaira, Kyoichi [Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan); Gunma University Hospital, Oncology Center, Maebashi, Gunma (Japan); Miyashita, Go; Negishi, Akihide; Yokoo, Satoshi [Gunma University Graduate School of Medicine, Department of Stomatology and Maxillofacial Surgery, Maebashi, Gunma (Japan); Oriuchi, Noboru; Higuchi, Tetsuya; Tsushima, Yoshito [Gunma University Graduate School of Medicine, Department of Diagnostic Radiology and Nuclear Medicine, Maebashi, Gunma (Japan); Kanai, Yoshikatsu [Osaka University, Division of Bio-system Pharmacology, Graduate School of Medicine, Osaka (Japan); Oyama, Tetsunari [Gunma University Graduate School of Medicine, Department of Diagnostic Pathology, Maebashi, Gunma (Japan)

2013-10-15

l-[3-{sup 18}F]-{alpha}-Methyltyrosine ({sup 18}F-FAMT) was developed as an amino acid tracer for PET imaging to provide better specificity than 2-[{sup 18}F]fluoro-2-deoxy-d-glucose ({sup 18}F-FDG) PET for cancer diagnosis. We investigated the diagnostic usefulness of {sup 18}F-FAMT in oral squamous cell carcinoma (OSCC). The correlation between tumour uptake of {sup 18}F-FAMT and L-type amino acid transporter 1 (LAT1) expression was determined. The study group comprised 68 OSCC patients who underwent both {sup 18}F-FAMT and {sup 18}F-FDG PET. Resected tumour sections were stained by immunohistochemistry for LAT1, CD98 and Ki-67, and microvessel density was determined in terms of CD34 and p53 expression. The sensitivity of primary tumour detection by {sup 18}F-FAMT and {sup 18}F-FDG PET was 98 % and 100 %, respectively. The sensitivity, specificity and accuracy of {sup 18}F-FAMT PET for detecting malignant lymph nodes were 68 %, 99 % and 97 %, respectively, and equivalent values for {sup 18}F-FDG PET were 84 %, 94 % and 94 %, respectively. The specificity and accuracy of {sup 18}F-FAMT were significantly higher than those of {sup 18}F-FDG. The uptake of {sup 18}F-FAMT was significantly correlated with LAT1 expression, cell proliferation and advanced stage. The expression of LAT1 in OSCC cells was closely correlated with CD98 levels, cell proliferation and angiogenesis. {sup 18}F-FAMT PET showed higher specificity for detecting malignant lesions than {sup 18}F-FDG PET. The uptake of {sup 18}F-FAMT by OSCC cells can be determined by the presence of LAT1 expression and tumour cell proliferation. (orig.)

PET/CT in lymphoma patients; PET-CT bei Lymphompatienten

Energy Technology Data Exchange (ETDEWEB)

Steinert, H.C. [Universitaetsspital Zuerich, Klinik und Poliklinik fuer Nuklearmedizin (Switzerland)

2004-11-01

First results of PET/CT in Hodgkin's disease (HD) and aggressive non-Hodgkin's lymphoma (NHL) are reported. From March 2001 to August 2004 822 PET/CT were performed at our clinic in lymphoma patients for primary staging, restaging after therapy, and diagnosis of recurrence. For coregistration non contrast-enhanced low-dose CT were used. Due to the exact anatomic localization of {sup 18}F-FDG accumulating lesions equivocal or false positive PET findings are avoided. In comparison to contrast enhanced CT, PET/CT has a higher sensitivity and specificity in patients with HD and aggressive NHL. Integration of PET/CT in treatment planning of radiation therapy optimizes the field volume. Even in the initial phase of clinical evaluation, PET/CT has proven useful in staging and restaging of lymphoma. The exact anatomic localization of the PET findings is essential for a precise report, for treatment planning of radiation therapy, and for planning surgical biopsy. (orig.) [German] Erste Ergebnisse der PET-CT bei Morbus Hodgkin (HD) und den aggressiven Non-Hodgkin-Lymphomen (NHL) werden beschrieben. Von Maerz 2001 bis August 2004 wurden 822 PET-CT bei Lymphompatienten zum primaeren Staging, zum Restaging nach Therapie und zur Rezidivdiagnostik an unserer Klinik durchgefuehrt. Fuer die Koregistration wurde ein Low-dose-CT ohne i.v.-Kontrastmittel verwendet. Durch die exakte anatomische Zuordnung der {sup 18}F-FDG aufnehmenden Laesionen wurden unklare oder falsch-positive PET-Befunde vermieden. Die PET-CT erzielte im Vergleich zur KM-verstaerkten CT eine hoehere Sensitivitaet und Spezifitaet bei Patienten mit HD und aggressiven NHL. Die Integration der PET-CT in die Planung der Strahlentherapie fuehrte zu einer Optimierung der Feldgrenzen. Die PET-CT hat sich bereits in der Phase der initialen klinischen Evaluation als wertvoll beim Staging und Restaging von Lymphomen erwiesen. Die exakte anatomische Zuordnung der PET-Informationen ist fuer eine sichere Befundung

Distribution and behavior of major and trace elements in Tokyo Bay, Mutsu Bay and Funka Bay marine sediments

International Nuclear Information System (INIS)

Honda, Teruyuki; Kimura, Ken-ichiro

2003-01-01

Fourteen major and trace elements in marine sediment core samples collected from the coasts along eastern Japan, i.e. Tokyo Bay (II) (the recess), Tokyo Bay (IV) (the mouth), Mutsu Bay and Funka Bay and the Northwest Pacific basin as a comparative subject were determined by the instrumental neutron activation analysis (INAA). The sedimentation rates and sedimentary ages were calculated for the coastal sediment cores by the 210 Pb method. The results obtained in this study are summarized as follows: (1) Lanthanoid abundance patterns suggested that the major origin of the sediments was terrigenous material. La*/Lu* and Ce*/La* ratios revealed that the sediments from Tokyo Bay (II) and Mutsu Bay more directly reflected the contribution from river than those of other regions. In addition, the Th/Sc ratio indicated that the coastal sediments mainly originated in the materials from the volcanic island-arcs, Japanese islands, whereas those from the Northwest Pacific mainly from the continent. (2) The correlation between the Ce/U and Th/U ratios with high correlation coefficients of 0.920 to 0.991 indicated that all the sediments from Tokyo Bay (II) and Funka Bay were in reducing conditions while at least the upper sediments from Tokyo Bay (IV) and Mutsu Bay were in oxidizing conditions. (3) It became quite obvious that the sedimentation mechanism and the sedimentation environment at Tokyo Bay (II) was different from those at Tokyo Bay (IV), since the sedimentation rate at Tokyo Bay (II) was approximately twice as large as that at Tokyo Bay (IV). The sedimentary age of the 5th layer (8∼10 cm in depth) from Funka Bay was calculated at approximately 1940∼50, which agreed with the time, 1943∼45 when Showa-shinzan was formed by the eruption of the Usu volcano. (author)

CT, PET and MR-Imaging in experimental baromedical research

DEFF Research Database (Denmark)

Hansen, Kasper

Pa pressurisation, and repeatedly after 500 kPa/min decompression. After MRI, venous bubble development was monitored using ultrasound. Second, preclinical μCT, PET/MRI, and high-field 9.4 T MR-Imaging systems evaluated changes in cerebral standard uptake value (SUV) of F-FDG, changes in cerebral blood flow (delta...... it is intrinsically difficult to study humans or animals inside a pressure chamber. We have developed a preclinical pressure chamber system compatible with CT, PET and MR-imaging during pressurisation up to 1.013 mPa, which allows for anatomical visualisations and measurements of certain physiological processes...... in vivo during pressurisation. Material and methods: Anaesthetised rats (simulated diving and control groups) underwent the following imaging protocols: First, a 3T clinical MRI-system was employed to evaluate in vivo cerebral relaxation parameters (T1, T2 and T2*). MRI was performed before, during 709 k...

Do carotid MR surface coils affect PET quantification in PET/MR imaging?

International Nuclear Information System (INIS)

Willemink, Martin J; Eldib, Mootaz; Leiner, Tim; Fayad, Zahi A; Mani, Venkatesh

2015-01-01

To evaluate the effect of surface coils for carotid MR imaging on PET quantification in a clinical simultaneous whole-body PET/MR scanner. A cylindrical phantom was filled with a homogeneous 2L water-FDG mixture at a starting dose of 301.2MBq. Clinical PET/MR and PET/CT systems were used to acquire PET-data without a coil (reference standard) and with two carotid MRI coils (Siemens Special Purpose 8-Channel and Machnet 4-Channel Phased Array). PET-signal attenuation was evaluated with Osirix using 51 (PET/MR) and 37 (PET/CT) circular ROIs. Mean and maximum standardized uptake values (SUVs) were quantified for each ROI. Furthermore, SUVs of PET/MR and PET/CT were compared. For validation, a patient was scanned with an injected dose of 407.7MBq on both a PET/CT and a PET/MR system without a coil and with both coils. PET/MR underestimations were -2.2% (Siemens) and -7.8% (Machnet) for SUVmean, and -1.2% (Siemens) and -3.3% (Machnet) for SUVmax, respectively. For PET/CT, underestimations were -1.3% (Siemens) and -1.4% (Machnet) for SUVmean and -0.5% (both Siemens and Machnet) for SUVmax, respectively using no coil data as reference. Except for PET/CT SUVmax values all differences were significant. SUVs differed significantly between PET/MR and PET/CT with SUVmean values of 0.51-0.55 for PET/MR and 0.68-0.69 for PET/CT, respectively. The patient examination showed that median SUVmean values measured in the carotid arteries decreased from 0.97 without a coil to 0.96 (Siemens) and 0.88 (Machnet). Carotid surface coils do affect attenuation correction in both PET/MR and PET/CT imaging. Furthermore, SUVs differed significantly between PET/MR and PET/CT.

The impact of 18F-FDG PET/CT in patients with liver metastases

International Nuclear Information System (INIS)

Chua, Siew C.; Groves, Ashley M.; Kayani, Irfan; Menezes, Leon; Gacinovic, Svetislav; Du, Yong; Bomanji, Jamshed B.; Ell, Peter J.

2007-01-01

The aim of this study was to assess the performance of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) versus dedicated contrast-enhanced CT (CECT) in the detection of metastatic liver disease. All patients that presented to our Institution with suspected metastatic liver disease who underwent 18 F-FDG PET/CT and CECT within 6 weeks of each other, were retrospectively analyzed, covering a 5-year period. One hundred and thirty-one patients (67 men, 64 women; mean age 62) were identified. Seventy-five had colorectal carcinoma and 56 had other malignancies. The performance of CECT and that of 18 F-FDG-PET/CT in detecting liver metastases were compared. The ability of each to detect local recurrence, extrahepatic metastases and to alter patient management was recorded. The final diagnosis was based on histology, clinical and radiological follow-up (mean 23 months). In detecting hepatic metastases, 18 F-FDG-PET/CT yielded 96% sensitivity and 75% specificity, whilst CECT showed 88% sensitivity and 25% specificity. 18 F-FDG-PET/CT and CECT were concordant in 102 out of 131 patients (78%). In the colorectal group 18 F-FDG-PET/CT showed 94% sensitivity and 75% specificity, whilst CECT had 91% sensitivity and 25% specificity. In the noncolorectal group 18 F-FDG-PET/CT showed 98% sensitivity and 75% specificity whilst CECT had 85% sensitivity and 25% specificity. Overall, 18 F-FDG-PET/CT altered patient management over CECT in 25% of patients. CECT did not alter patient management over 18 F-FDG-PET/CT alone in any patients. 18 F-FDG-PET/CT performed better in detecting metastatic liver disease than CECT in both colorectal and noncolorectal malignancies, and frequently altered patient management. The future role of CECT in these patients may need to be re-evaluated to avoid potentially unnecessary duplication of investigation where 18 F-PET/CT is readily available. (orig.)

Evaluation of the PET component of simultaneous [18F]choline PET/MRI in prostate cancer: comparison with [18F]choline PET/CT

International Nuclear Information System (INIS)

Wetter, Axel; Lipponer, Christine; Nensa, Felix; Altenbernd, Jens-Christian; Schlosser, Thomas; Lauenstein, Thomas; Heusch, Philipp; Ruebben, Herbert; Bockisch, Andreas; Poeppel, Thorsten; Nagarajah, James

2014-01-01

The aim of this study was to evaluate the positron emission tomography (PET) component of [ 18 F]choline PET/MRI and compare it with the PET component of [ 18 F]choline PET/CT in patients with histologically proven prostate cancer and suspected recurrent prostate cancer. Thirty-six patients were examined with simultaneous [ 18 F]choline PET/MRI following combined [ 18 F]choline PET/CT. Fifty-eight PET-positive lesions in PET/CT and PET/MRI were evaluated by measuring the maximum and mean standardized uptake values (SUV max and SUV mean ) using volume of interest (VOI) analysis. A scoring system was applied to determine the quality of the PET images of both PET/CT and PET/MRI. Agreement between PET/CT and PET/MRI regarding SUV max and SUV mean was tested using Pearson's product-moment correlation and Bland-Altman analysis. All PET-positive lesions that were visible on PET/CT were also detectable on PET/MRI. The quality of the PET images was comparable in both groups. Median SUV max and SUV mean of all lesions were significantly lower in PET/MRI than in PET/CT (5.2 vs 6.1, p max of PET/CT and PET/MRI (R = 0.86, p mean of PET/CT and PET/MRI (R = 0.81, p max of PET/CT vs PET/MRI and -1.12 to +2.23 between SUV mean of PET/CT vs PET/MRI. PET image quality of PET/MRI was comparable to that of PET/CT. A highly significant correlation between SUV max and SUV mean was found. Both SUV max and SUV mean were significantly lower in [ 18 F]choline PET/MRI than in [ 18 F]choline PET/CT. Differences of SUV max and SUV mean might be caused by different techniques of attenuation correction. Furthermore, differences in biodistribution and biokinetics of [ 18 F]choline between the subsequent examinations and in the respective organ systems have to be taken into account. (orig.)

[Principles of PET].

Science.gov (United States)

Beuthien-Baumann, B

2018-05-01

Positron emission tomography (PET) is a procedure in nuclear medicine, which is applied predominantly in oncological diagnostics. In the form of modern hybrid machines, such as PET computed tomography (PET/CT) and PET magnetic resonance imaging (PET/MRI) it has found wide acceptance and availability. The PET procedure is more than just another imaging technique, but a functional method with the capability for quantification in addition to the distribution pattern of the radiopharmaceutical, the results of which are used for therapeutic decisions. A profound knowledge of the principles of PET including the correct indications, patient preparation, and possible artifacts is mandatory for the correct interpretation of PET results.

Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

International Nuclear Information System (INIS)

Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah

2014-01-01

Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after 18 F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast-enhanced PET

Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

Energy Technology Data Exchange (ETDEWEB)

Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah [Yeungnam Univ. Hospital, Daegu (Korea, Republic of)

2014-03-15

Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after {sup 18}F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast

Real-life Experience for Integration of PET-CT in the Treatment of Hodgkin Lymphoma in Lebanon.

Science.gov (United States)

Sakr, Riwa; Massoud, Marcel; Kerbage, Fouad; Rached, Layale; Zeghondy, Jean; Akoury, Elie; Nasr, Fady; Chahine, Georges

2017-07-01

Hodgkin lymphoma (HL) is a highly curable disease; Lebanon. We analyzed the data regarding the usage of PET-CT at diagnosis, during treatment (interim PET), and at the end of treatment. We also analyzed the PET-CT findings from 2009 to 2015. The first PET-CT system was introduced in Lebanon in April 2002 but was not used for the evaluation of HL. Early in 2009, we started to incorporate PET-CT into the treatment of HL. By the end of 2009, 70% of patients were undergoing PET-CT at diagnosis and at the end of treatment. This proportion remained constant until 2013, when an increase occurred, with ≤ 94% of patients undergoing PET-CT at diagnosis. The usage of CT at diagnosis decreased significantly from 70% before 2009 to 52% after 2015. In contrast, CT usage at the end of treatment has fluctuated from 10% in 2009 to 0% in 2012, 2013, and 2014 and 11.76% in 2015. Functional imaging techniques are increasing in popularity compared with anatomic imaging. The usage of PET-CT has emerged as a highly valuable staging and follow-up method in the treatment of HL 8 years after the introduction of PET in Lebanon. PET was used first to improve the staging, then to evaluate the treatment response, and, recently, to tailor therapy according to the response. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic Role of F-18 FDG PET/CT in the Follow-up of Patients with Colorectal Cancer: Comparison with Serum CEA, CA 19-9 Levels and Computed Tomography

Energy Technology Data Exchange (ETDEWEB)

Kang, Sung Min; Song, Bong Il; Lee, Hong Je; Seo, Ji Hyoung; Lee, Sang Woo; Yoo, Jeong Soo; Ahn, Byeong Cheol; Lee, Jae Tae; Choi, Kyu Suk; Jun, Soo Han [Kyungpook National University Hospital, Daegu (Korea, Republic of)

2009-04-15

Early detection of recurrence is an important factor for long term survival of patients with colorectal cancer. Measurement of serum levels of CEA, CA 19-9, CT and PET/CT has been commonly used in the postoperative surveillance of colorectal cancer. The purpose of this study was to compare the diagnostic ability of PET/CT, tumor marker and CT for recurrence in colorectal cancer patients after treatment. F-18 FDG PET/CT imaging was performed in 189 colorectal cancer patients who underwent curative surgical resection and/or chemotherapy. Measurement of serum levels of CEA, CA 19-9 and CT imaging were performed within 2 months of PET/CT examination. Final diagnosis of recurrence was made by biopsy, radiologic studies or clinical follow-up for 6 months after each study. Overall sensitivity, specificity of PET/CT was 94.7%, 91.1%, while those of serum CEA were 44.7% and 97.3%, respectively. Sensitivity and specificity were 94.2%, 90.4% for PET/CT and better than those of combined CEA and CA 19-9 measurement (52.1%, 88.5%) in 174 patients measured available both CEA and CA 19-9 data. In 115 patients with both tumor markers and CT images available, PET/CT showed similar sensitivity but higher specificity (92.9%, 91.3%) compared to combination of tumor markers and CT images (92.9%, 74.1%). PET/CT was superior for detection of recurred colorectal cancer patients compared with both CEA, CA 19-9, and even with combination of both tumor markers and CT. Therefore PET/CT could be used as a routine surveillance examination to detect recurrence or metastasis of colorectal cancer.

Lung PET scan

Science.gov (United States)

... Chest PET scan; Lung positron emission tomography; PET - chest; PET - lung; PET - tumor imaging; ... Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging . 6th ed. Philadelphia, ...

Prospective evaluation of fluciclovine (18F) PET-CT and MRI in detection of recurrent prostate cancer in non-prostatectomy patients.

Science.gov (United States)

Akin-Akintayo, Oladunni; Tade, Funmilayo; Mittal, Pardeep; Moreno, Courtney; Nieh, Peter T; Rossi, Peter; Patil, Dattatraya; Halkar, Raghuveer; Fei, Baowei; Master, Viraj; Jani, Ashesh B; Kitajima, Hiroumi; Osunkoya, Adeboye O; Ormenisan-Gherasim, Claudia; Goodman, Mark M; Schuster, David M

2018-05-01

To investigate the disease detection rate, diagnostic performance and interobserver agreement of fluciclovine ( 18 F) PET-CT and multiparametric magnetic resonance imaging (mpMR) in recurrent prostate cancer. Twenty-four patients with biochemical failure after non-prostatectomy definitive therapy, 16/24 of whom had undergone brachytherapy, underwent fluciclovine PET-CT and mpMR with interpretation by expert readers blinded to patient history, PSA and other imaging results. Reference standard was established via a multidisciplinary truth panel utilizing histology and clinical follow-up (22.9 ± 10.5 months) and emphasizing biochemical control. The truth panel was blinded to investigative imaging results. Diagnostic performance and interobserver agreement (kappa) for the prostate and extraprostatic regions were calculated for each of 2 readers for PET-CT (P1 and P2) and 2 different readers for mpMR (M1 and M2). On a whole body basis, the detection rate for fluciclovine PET-CT was 94.7% (both readers), while it ranged from 31.6-36.8% for mpMR. Kappa for fluciclovine PET-CT was 0.90 in the prostate and 1.0 in the extraprostatic regions. For mpMR, kappa was 0.25 and 0.74, respectively. In the prostate, 22/24 patients met the reference standard with 13 malignant and 9 benign results. Sensitivity, specificity and positive predictive value (PPV) were 100.0%, 11.1% and 61.9%, respectively for both PET readers. For mpMR readers, values ranged from 15.4-38.5% for sensitivity, 55.6-77.8% for specificity and 50.0-55.6% for PPV. For extraprostatic disease determination, 18/24 patients met the reference standard. Sensitivity, specificity and PPV were 87.5%, 90.0% and 87.5%, respectively, for fluciclovine PET-CT, while for mpMR, sensitivity ranged from 50 to 75%, specificity 70-80% and PPV 57-75%. The disease detection rate for fluciclovine PET-CT in non-prostatectomy patients with biochemical failure was 94.7% versus 31.6-36.8% for mpMR. For extraprostatic disease detection

Simultaneous PET/MRI with 13C magnetic resonance spectroscopic imaging (hyperPET): phantom-based evaluation of PET quantification

DEFF Research Database (Denmark)

Hansen, Adam E.; Andersen, Flemming L.; Henriksen, Sarah T.

2016-01-01

Background: Integrated PET/MRI with hyperpolarized 13C magnetic resonance spectroscopic imaging (13C-MRSI) offers simultaneous, dual-modality metabolic imaging. A prerequisite for the use of simultaneous imaging is the absence of interference between the two modalities. This has been documented...... for a clinical whole-body system using simultaneous 1 H-MRI and PET but never for 13C-MRSI and PET. Here, the feasibility of simultaneous PET and 13C-MRSI as well as hyperpolarized 13C-MRSI in an integrated whole-body PET/MRI hybrid scanner is evaluated using phantom experiments. Methods: Combined PET and 13C......-MRSI phantoms including a NEMA [18F]-FDG phantom, 13C-acetate and 13C-urea sources, and hyperpolarized 13C-pyruvate were imaged repeatedly with PET and/or 13C-MRSI. Measurements evaluated for interference effects included PET activity values in the largest sphere and a background region; total number of PET...

Bone metastasis in patients with non-small cell lung cancer: The diagnostic role of F-18 FDG PET/CT

International Nuclear Information System (INIS)

Liu Ningbo; Ma Li; Zhou Wei; Pang Qingsong; Hu Man; Shi Fang; Fu Zheng; Li Minghuan; Yang Guoren; Yu Jinming

2010-01-01

Purpose: To evaluate the performance of F-18 FDG PET/CT in the detection of bone metastasis in non-small cell lung cancer (NSCLC) patients. Materials and methods: Three hundred and sixty-two consecutive NSCLC patients who underwent F-18 FDG PET/CT scanning were retrospectively analyzed. Each image of PET/CT, combined CT, and PET was performed at 10 separate areas and interpreted blindly and separately. The sensitivity, specificity and accuracy of F-18 FDG PET/CT, combined CT and F-18 FDG PET were calculated and the results were statistically analyzed. Results: Bone metastasis was confirmed in 82 patients with 331 positive segments based on the image findings and clinical follow-up. On patient-based analysis, the sensitivity of F-18 FDG PET/CT (93.9%) was significantly higher than those of combined CT (74.4%) and F-18 FDG PET (84.1%), respectively (p < 0.05). The overall specificity and accuracy of combined CT, F-18 FDG PET, and F-18 FDG PET/CT were 90.7%, 93.2%, 98.9% and 87.0%, 91.2%, and 97.8%, respectively (compared with PET/CT, p < 0.05). On segment-based analysis, the sensitivity of the three modalities were 79.5%, 94.3%, and 98.8%, respectively (compared with PET/CT, p < 0.05). The overall specificity and accuracy of the three modalities were 87.9%, 89.2%, 98.6% and 84.5%, 91.2%, 98.7%, respectively (compared with PET/CT, p < 0.05). Conclusion: F-18 FDG PET/CT is superior to F-18 FDG PET or combined CT in detecting bone metastasis of NSCLC patients because of the complementation of CT and PET. It is worth noting that the added value of F-18 FDG PET/CT may beneficially impact the clinical management of NSCLC.

Positron Emission Tomography (PET)

International Nuclear Information System (INIS)

Welch, M.J.

1990-01-01

Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs

Positron Emission Tomography (PET)

Science.gov (United States)

Welch, M. J.

1990-01-01

Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

Positron Emission Tomography (PET)

Energy Technology Data Exchange (ETDEWEB)

Welch, M.J.

1990-01-01

Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET. 22 figs.

Indeterminate findings on oncologic PET/CT: What difference dose PET/MRI make?

Energy Technology Data Exchange (ETDEWEB)

Fraum, Tyler J.; Fowler, Kathryn J.; McConathy, Jonathan; Dehdashti, Farokh [Mallinckrodt Institute of Radiology, Washington University School of Medicine, Saint Louis (United States)

2016-12-15

Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-[{sup 18}F]fluoro-D-glucose (FDG) has become the standard of care for the initial staging and subsequent treatment response assessment of many different malignancies. Despite this success, PET/CT is often supplemented by MRI to improve assessment of local tumor invasion and to facilitate detection of lesions in organs with high background FDG uptake. Consequently, PET/MRI has the potential to expand the clinical value of PET examinations by increasing reader certainty and reducing the need for subsequent imaging. This study evaluates the ability of FDG-PET/MRI to clarify findings initially deemed indeterminate on clinical FDG-PET/CT studies. A total of 190 oncology patients underwent whole-body PET/CT, immediately followed by PET/MRI utilizing the same FDG administration. Each PET/CT was interpreted by our institution's nuclear medicine service as a standard-of-care clinical examination. Review of these PET/CT reports identified 31 patients (16 %) with indeterminate findings. Two readers evaluated all 31 PET/CT studies, followed by the corresponding PET/MRI studies. A consensus was reached for each case, and changes in interpretation directly resulting from PET/MRI review were recorded. Interpretations were then correlated with follow-up imaging, pathology results, and other diagnostic studies. In 18 of 31 cases with indeterminate findings on PET/CT, PET/MRI resulted in a more definitive interpretation by facilitating the differentiation of infection/inflammation from malignancy (15/18), the accurate localization of FDG-avid lesions (2/18), and the characterization of incidental non-FDG-avid solid organ lesions (1/18). Explanations for improved reader certainty with PET/MRI included the superior soft tissue contrast of MRI and the ability to assess cellular density with diffusion-weighted imaging. The majority (12/18) of such cases had an appropriate standard of reference; in all 12 cases

Indeterminate findings on oncologic PET/CT: What difference dose PET/MRI make?

International Nuclear Information System (INIS)

Fraum, Tyler J.; Fowler, Kathryn J.; McConathy, Jonathan; Dehdashti, Farokh

2016-01-01

Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-["1"8F]fluoro-D-glucose (FDG) has become the standard of care for the initial staging and subsequent treatment response assessment of many different malignancies. Despite this success, PET/CT is often supplemented by MRI to improve assessment of local tumor invasion and to facilitate detection of lesions in organs with high background FDG uptake. Consequently, PET/MRI has the potential to expand the clinical value of PET examinations by increasing reader certainty and reducing the need for subsequent imaging. This study evaluates the ability of FDG-PET/MRI to clarify findings initially deemed indeterminate on clinical FDG-PET/CT studies. A total of 190 oncology patients underwent whole-body PET/CT, immediately followed by PET/MRI utilizing the same FDG administration. Each PET/CT was interpreted by our institution's nuclear medicine service as a standard-of-care clinical examination. Review of these PET/CT reports identified 31 patients (16 %) with indeterminate findings. Two readers evaluated all 31 PET/CT studies, followed by the corresponding PET/MRI studies. A consensus was reached for each case, and changes in interpretation directly resulting from PET/MRI review were recorded. Interpretations were then correlated with follow-up imaging, pathology results, and other diagnostic studies. In 18 of 31 cases with indeterminate findings on PET/CT, PET/MRI resulted in a more definitive interpretation by facilitating the differentiation of infection/inflammation from malignancy (15/18), the accurate localization of FDG-avid lesions (2/18), and the characterization of incidental non-FDG-avid solid organ lesions (1/18). Explanations for improved reader certainty with PET/MRI included the superior soft tissue contrast of MRI and the ability to assess cellular density with diffusion-weighted imaging. The majority (12/18) of such cases had an appropriate standard of reference; in all 12 cases, the

Humic Substances from Manila Bay and Bolinao Bay Sediments

Directory of Open Access Journals (Sweden)

Elma Llaguno

1997-12-01

Full Text Available The C,H,N composition of sedimentary humic acids (HA extracted from three sites in Manila Bay and six sites in Bolinao Bay yielded H/C atomic ratios of 1.1-1.4 and N/C atomic ratios of 0.09 - 0.16. The Manila Bay HA's had lower H/C and N/C ratios compared to those from Bolinao Bay. The IR spectra showed prominent aliphatic C-H and amide I and II bands. Manila Bay HA's also had less diverse molecular composition based on the GC-MS analysis of the CuO and alkaline permanganate oxidation products of the humic acids.

PET and PET/CT in tumour of undetermined origin; PET y PET/CT en tumor de origen indeterminado

Energy Technology Data Exchange (ETDEWEB)

Garcia O, J R [Nuclear Medicine and Molecular Imaging, PET/CT, Centro Medico ABC, Mexico D.F. (Mexico)

2007-07-01

In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

Simultaneous PET/MRI with (13)C magnetic resonance spectroscopic imaging (hyperPET): phantom-based evaluation of PET quantification.

Science.gov (United States)

Hansen, Adam E; Andersen, Flemming L; Henriksen, Sarah T; Vignaud, Alexandre; Ardenkjaer-Larsen, Jan H; Højgaard, Liselotte; Kjaer, Andreas; Klausen, Thomas L

2016-12-01

Integrated PET/MRI with hyperpolarized (13)C magnetic resonance spectroscopic imaging ((13)C-MRSI) offers simultaneous, dual-modality metabolic imaging. A prerequisite for the use of simultaneous imaging is the absence of interference between the two modalities. This has been documented for a clinical whole-body system using simultaneous (1)H-MRI and PET but never for (13)C-MRSI and PET. Here, the feasibility of simultaneous PET and (13)C-MRSI as well as hyperpolarized (13)C-MRSI in an integrated whole-body PET/MRI hybrid scanner is evaluated using phantom experiments. Combined PET and (13)C-MRSI phantoms including a NEMA [(18)F]-FDG phantom, (13)C-acetate and (13)C-urea sources, and hyperpolarized (13)C-pyruvate were imaged repeatedly with PET and/or (13)C-MRSI. Measurements evaluated for interference effects included PET activity values in the largest sphere and a background region; total number of PET trues; and (13)C-MRSI signal-to-noise ratio (SNR) for urea and acetate phantoms. Differences between measurement conditions were evaluated using t tests. PET and (13)C-MRSI data acquisition could be performed simultaneously without any discernible artifacts. The average difference in PET activity between acquisitions with and without simultaneous (13)C-MRSI was 0.83 (largest sphere) and -0.76 % (background). The average difference in net trues was -0.01 %. The average difference in (13)C-MRSI SNR between acquisitions with and without simultaneous PET ranged from -2.28 to 1.21 % for all phantoms and measurement conditions. No differences were significant. The system was capable of (13)C-MRSI of hyperpolarized (13)C-pyruvate. Simultaneous PET and (13)C-MRSI in an integrated whole-body PET/MRI hybrid scanner is feasible. Phantom experiments showed that possible interference effects introduced by acquiring data from the two modalities simultaneously are small and non-significant. Further experiments can now investigate the benefits of simultaneous PET and

Volume-based quantitative FDG PET/CT metrics and their association with optimal debulking and progression-free survival in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery

International Nuclear Information System (INIS)

Vargas, H.A.; Burger, I.A.; Micco, M.; Sosa, R.E.; Weber, W.; Hricak, H.; Sala, E.; Goldman, D.A.; Chi, D.S.

2015-01-01

Our aim was to evaluate the associations between quantitative 18 F-fluorodeoxyglucose positron-emission tomography (FDG-PET) uptake metrics, optimal debulking (OD) and progression-free survival (PFS) in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery. Fifty-five patients with recurrent ovarian cancer underwent FDG-PET/CT within 90 days prior to surgery. Standardized uptake values (SUV max ), metabolically active tumour volumes (MTV), and total lesion glycolysis (TLG) were measured on PET. Exact logistic regression, Kaplan-Meier curves and the log-rank test were used to assess associations between imaging metrics, OD and PFS. MTV (p = 0.0025) and TLG (p = 0.0043) were associated with OD; however, there was no significant association between SUV max and debulking status (p = 0.83). Patients with an MTV above 7.52 mL and/or a TLG above 35.94 g had significantly shorter PFS (p = 0.0191 for MTV and p = 0.0069 for TLG). SUV max was not significantly related to PFS (p = 0.10). PFS estimates at 3.5 years after surgery were 0.42 for patients with an MTV ≤ 7.52 mL and 0.19 for patients with an MTV > 7.52 mL; 0.46 for patients with a TLG ≤ 35.94 g and 0.15 for patients with a TLG > 35.94 g. FDG-PET metrics that reflect metabolic tumour burden are associated with optimal secondary cytoreductive surgery and progression-free survival in patients with recurrent ovarian cancer. (orig.)

Pet Allergy Quiz

Science.gov (United States)

... Treatments ▸ Allergies ▸ Pet Allergy ▸ Pet Allergy Quiz Share | Pet Allergy Quiz More than half of U.S. households ... cat family. Yet, millions of people suffer from pet allergies. Take this quiz to test your knowledge ...

Colorectal cancer staging: comparison of whole-body PET/CT and PET/MR.

Science.gov (United States)

Catalano, Onofrio A; Coutinho, Artur M; Sahani, Dushyant V; Vangel, Mark G; Gee, Michael S; Hahn, Peter F; Witzel, Thomas; Soricelli, Andrea; Salvatore, Marco; Catana, Ciprian; Mahmood, Umar; Rosen, Bruce R; Gervais, Debra

2017-04-01

Correct staging is imperative for colorectal cancer (CRC) since it influences both prognosis and management. Several imaging methods are used for this purpose, with variable performance. Positron emission tomography-magnetic resonance (PET/MR) is an innovative imaging technique recently employed for clinical application. The present study was undertaken to compare the staging accuracy of whole-body positron emission tomography-computed tomography (PET/CT) with whole-body PET/MR in patients with both newly diagnosed and treated colorectal cancer. Twenty-six patients, who underwent same day whole-body (WB) PET/CT and WB-PET/MR, were evaluated. PET/CT and PET/MR studies were interpreted by consensus by a radiologist and a nuclear medicine physician. Correlations with prior imaging and follow-up studies were used as the reference standard. Correct staging was compared between methods using McNemar's Chi square test. The two methods were in agreement and correct for 18/26 (69%) patients, and in agreement and incorrect for one patient (3.8%). PET/MR and PET/CT stages for the remaining 7/26 patients (27%) were discordant, with PET/MR staging being correct in all seven cases. PET/MR significantly outperformed PET/CT overall for accurate staging (P = 0.02). PET/MR outperformed PET/CT in CRC staging. PET/MR might allow accurate local and distant staging of CRC patients during both at the time of diagnosis and during follow-up.

Direct comparison study between FDG-PET and IMP-SPECT for diagnosing Alzheimer's disease using 3D-SSP analysis in the same patients

International Nuclear Information System (INIS)

Nihashi, Takashi; Hayasaka, Kazumasa; Yatsuya, Hiroshi

2007-01-01

The purpose of this study was to evaluate and compare the diagnostic ability of 2-[ 18 F]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) and N-isopropyl-p- 123 I iodoamphetamine single photon emission computed tomography (IMP-SPECT) using three-dimensional stereotactic surface projections (3D-SSP) in patients with moderate Alzheimer's disease (AD). FDG-PET and IMP-SPECT were performed within 3 months in 14 patients with probable moderate AD. Z-score maps of FDG-PET and IMP-SPECT images of a patient were obtained by comparison with data obtained from control subjects. Four expert physicians evaluated and graded the glucose hypometabolism and regional cerebral blood flow (rCBF), focusing in particular on the posterior cingulate gyri/precunei and parietotemporal regions, and determined the reliability for AD. Receiver operating characteristic (ROC) curves were applied to the results for clarification. To evaluate the correlation between two modalities, the regions of interest (ROIs) were set in the posterior cingulate gyri/precunei and parietotemporal region on 3D-SSP images, and mean Z-values were calculated. No significant difference was observed in the area under the ROC curve (AUC) between FDG-PET and IMP-SPECT images (FDG-PET 0.95, IMP-SPECT 0.94). However, a significant difference (P<0.05) was observed in the AUC for the posterior cingulate gyri/precuneus (FDG-PET 0.94, IMP-SPECT 0.81). The sensitivity and specificity of each modality were 86%, and 97% for FDG-PET and 70% and 100% for IMP-SPECT. We could find no significant difference between FDG-PET and IMP-SPECT in terms of diagnosing moderate AD using 3D-SSP. There was a high correlation between the two modalities in the parietotemporal region (Spearman's r=0.82, P<0.001). The correlation in the posterior cingulate gyri/precunei region was lower than that in the parietotemporal region (Spearman's r=0.63, P<0.016). (author)

TOF-PET/MR和TOF-PET/CT在体部恶性肿瘤SUVmax值的比较%Comparision of SUVmax of TOF-PET/MR and TOF-PET/CT in body malignant tumor

Institute of Scientific and Technical Information of China (English)

宋天彬; 卢洁; 崔碧霄; 马杰; 杨宏伟; 马蕾; 梁志刚

2017-01-01

目的 探讨时间飞行(TOF)技术PET/CT和PET/MR检查体部恶性病变SUVmax值的一致性.方法 回顾性分析接受TOF-PET/CT和TOF-PET/MR检查的体部恶性肿瘤患者20例,分为先PET/CT后PET/MR组和先PET/MR后PET/CT组,每组10例.采用Bland-Altma图评价两次检查病灶SUVmax值的一致性,采用多因素方差分析评价扫描顺序和机器类型对病灶的SUVmax测量值的影响.结果 TOF-PET/CT与TOF-PET/MR检查病灶的SUVmax值有较好的一致性[先PET/CT后PET/MR组:均值差为3.06,95％CI(-7.5,13.6),先PET/MR后PET/CT组:均值差3.0,95％CI(-2.4,8.3)].扫描顺序对于恶性病灶的SUVmax有影响(F=46.00,P＜0.001),而机器类型对恶性病灶的SUVmax值无影响(F=0.005,P=0.95).结论 TOF-PET/MR和TOF-PET/CT在体部恶性病变SUVmax值测量方面具有相当的诊断价值,且延迟显像SUVmax的增加与采集时间有关,而与检查机器类型无关.%Objective To explore the consistency of time-of-flight (TOF) technology of PET/MRI and PET/CT for max standardized uptake value (SUVmax) of body malignant tumors.Methods A retrospective analysis of TOF-PET/CT and TOF-PET/MR imaging data about twenty patients with body malignant tumors was performed.Patients were divided into two groups (each n=10),including PET/CT first and sequentially PET/MR group and PET/MR first and sequentially PET/CT group.Bland-Altman figure was used to evaluate consistency of SUVmax of malignant lesions between TOF-PET/CT and TOF-PET/MR.Multi-way ANOVA was used to analysis effect of machine type and exam order on SUVmaxof malignant lesions in TOF-PET/CT and TOF-PET/MR.Results SUVmax of malignant lesions in TOF-PET/CT and TOF-PET/MR had good consistency in two groups (PET/CT first and sequentially PET/MR group:Mean difference was 3.06,95％CI was [-7.5,13.6];PET/MR first and sequentially PET/CT group:Mean difference was 3.0,95％CI was [-2.4,8.3]).SUVmax was not influenced by machine type (F=0.005,P=0.95),but exam order (F=46.00,P＜0

Contribution of whole body F-18-FDG-PET and lymphoscintigraphy to the assessment of regional and distant metastases in cutaneous malignant melanoma. A pilot study

Energy Technology Data Exchange (ETDEWEB)

Klein, M.; Freedman, N.; Marciano, R.; Moshe, S.; Chisin, R. [Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Medical Biophysics and Nuclear Medicine; Lotem, M. [Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Oncology; Gimon, Z. [Hadassah Univ. Hospital, Jerusalem (Israel). Dept. of Surgery

2000-05-01

Aim: This pilot study describes use of whole body PET (WB PET) for staging of melanoma. WB PET in conjunction with lymphoscintigraphy (LS) for evaluating status of the sentinel lymph node (SLN) in primary melanoma was investigated with comparison to histopathological results. WB PET was also used both for primary and metastatic melanoma for screening for distant metastases, restaging and follow-up. Methods: Group I: 17 patients with primary cutaneous melanoma underwent LS, WB PET and SLN dissection. WB PET findings were compared with biopsy results at the SLN site and were used for screening for distant metastases. Group II: 17 patients with a history of melanoma underwent WB PET for follow-up and/or restaging. Results were confirmed or refuted by other radiological modalities or by biopsy of clinical follow-up. Results: Group I: Out of 20 SLNs identified by LS in the 17 patients, 18 were negative on WB PET and 2 were positive. 19/20 WB PET findings were confirmed either by histopathology or by clinical follow-up (20 mo). Accuracy was 94% for the assessment of the status of the SLN. Group II: WB PET findings altered staging and treatment in 12/17 patients and confirmed the validity of treatment in 3/17 patients. Overall, in 15/17 patients (88%), WB PET had an impact on treatment strategy. (orig.) [German] Ziel: Diese Pilot-Studie beschreibt die Anwendung der Ganzkoerper-PET (WB PET) zum Staging beim Melanom. Bei primaerem Melanom wurde WB PET in Verbindung mit der Lymphszintigraphie (LS) angewandt und mit der Histopathologie verglichen, um den Status des Sentinel Lymph Node (SLN) zu untersuchen. Zusaetzlich wurde WB PET fuer primaere und metastatische Melanome zum Screening auf Fernmetastasen, zum Restaging und zum Follow-up benutzt. Methoden: Gruppe I: 17 Patienten mit primaerem kutanem Melanom erhielten LS, WB PET und eine operative SLN-Entfernung. Die WB PET-Ergebnisse wurden mit den SLN-Biopsien verglichen und zum Screening fuer Fernmetastasen benutzt. Gruppe

Correlation of biological aggressiveness assessed by 11C-methionine PET and hypoxic burden assessed by 18F-fluoromisonidazole PET in newly diagnosed glioblastoma

International Nuclear Information System (INIS)

Kawai, Nobuyuki; Miyake, Keisuke; Okada, Masaki; Tamiya, Takashi; Maeda, Yukito; Yamamoto, Yuka; Nishiyama, Yoshihiro; Kudomi, Nobuyuki

2011-01-01

Glioblastoma multiforme (GBM) is characterized by tissue hypoxia associated with resistance to radiotherapy and chemotherapy. To clarify the biological link between hypoxia and tumour-induced neovascularization and tumour aggressiveness, we analysed detailed volumetric and spatial information of viable hypoxic tissue assessed by 18 F-fluoromisonidazole (FMISO) PET relative to neovascularization in Gd-enhanced MRI and tumour aggressiveness by L-methyl- 11 C-methionine (MET) PET in newly diagnosed GBMs. Ten patients with newly diagnosed GBMs were investigated with FMISO PET, MET PET and Gd-enhanced MRI before surgery. Tumour volumes were calculated by performing a three-dimensional threshold-based volume of interest (VOI) analysis for metabolically active volume on MET PET (MET uptake indices of ≥1.3 and ≥1.5) and Gd-enhanced volume on MRI. FMISO PET was scaled to the blood FMISO activity to create tumour to blood (T/B) images. The hypoxic volume (HV) was defined as the region with T/B greater than 1.2. PET and MR images of each patient were coregistered to analyse the spatial location of viable hypoxic tissue relative to neovascularization and active tumour extension. Metabolically active tumour volumes defined using MET uptake indices of ≥1.3 and ≥1.5 and the volumes of Gd enhancement showed a strong correlation (r = 0.86, p < 0.01 for an index of ≥1.3 and r = 0.77, p < 0.05 for an index of ≥1.5). The HVs were also excellently correlated with the volumes of Gd enhancement (r = 0.94, p < 0.01). The metabolically active tumour volumes as defined by a MET uptake index of ≥1.3 and the HVs exhibited a strong correlation (r = 0.87, p < 0.01). On superimposed images, the metabolically active area on MET PET defined by a MET uptake index of ≥1.3 was usually larger than the area of the Gd enhancement and about 20-30% of the MET area extended outside the area of the enhancement. On the other hand, the surface area of viable hypoxic tissue with a T/B cutoff of

18F-FDG PET as a single imaging modality in pediatric neuroblastoma. Comparison with abdomen CT and bone scintigraphy

International Nuclear Information System (INIS)

Choi, Yun Jung; Hwang, Hee Sung; Kim, Hyun Jeong; Jeong, Yong Hyu; Cho, Arthur; Lee, Jae Hoon; Yun, Mijin; Lee, Jong Doo; Kang, Won Jun

2014-01-01

The purpose of this study was to evaluate the diagnostic performance of 18 F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) as a single imaging agent in neuroblastoma in comparison with other imaging modalities. A total of 30 patients with pathologically proven neuroblastoma who underwent FDG PET for staging were enrolled. Diagnostic performance of FDG PET and abdomen CT was compared in detecting soft tissue lesions. FDG PET and bone scintigraphy (BS) were compared in bone metastases. Maximal standardized uptake value (SUVmax) of primary or recurrent lesions was calculated for quantitative analysis. Tumor FDG uptake was detected in 29 of 30 patients with primary neuroblastoma. On initial FDG PET, SUVmax of primary lesions were lower in early stage (I-II) than in late stage (III-IV) (3.03 vs. 5.45, respectively, p=0.019). FDG PET was superior to CT scan in detecting distant lymph nodes (23 vs. 18 from 23 lymph nodes). FDG PET showed higher accuracy to identify bone metastases than BS both on patient-based analyses (100 vs. 94.4% in sensitivity, 100 vs. 77.8% in specificity), and on lesion-based analyses (FDG PET: 203 lesions, BS: 86 lesions). Sensitivity and specificity of FDG PET to detect recurrence were 87.5% and 93.8, respectively. FDG PET was superior to CT in detecting distant LN metastasis and to BS in detecting skeletal metastasis in neuroblastoma. BS might be eliminated in the evaluation of neuroblastoma when FDG PET is performed. (author)

Dedicated brain PET system of PET/MR for brain research

International Nuclear Information System (INIS)

Cheng, Li; Liu, Yaqiang; Ma, Tianyu; Wang, Shi; Wei, Qingyang; Xu, Tianpeng

2015-01-01

This work is to replace PET ring in human brain PET/MR system with a dedicated wearable PET insert, aimed at improving both patient feasibility and system performance for brain imaging. The designed PET/MR system includes two parts: the inside parts, including a radio frequency (RF) coil and PET ring, are mounted on patient’s head, and the outside part, a MR imager, is dependent of patient. The RF coil is the innermost layer, surrounded by an outer PET-ring layer. They are supported by a MRcompatible structure. And both RF coil and PET detectors are placed inside a standard clinical 3-T MR imager. From the design of the system we can infer that some advantages can be achieved. First, high sensitivity will be achieved with the same amount crystals as the PET ring is more close to region-of-interest area, at a reduced cost. Second, by using a 2-layer depth of interaction (DOI) detector, the parallax effect can be minimized. The resolution will benefit from short positron range caused by magnetic field and smaller ring diameter will also reduce the effect of non-collinearity. Thirdly, as the PET ring is mounted on head, impact of patient motion will be reduced.

Dedicated brain PET system of PET/MR for brain research

Energy Technology Data Exchange (ETDEWEB)

Cheng, Li; Liu, Yaqiang; Ma, Tianyu; Wang, Shi; Wei, Qingyang; Xu, Tianpeng [Institute of Medical Physics, Department of Engineering Physics, Tsinghua University, Beijing (China)

2015-05-18

This work is to replace PET ring in human brain PET/MR system with a dedicated wearable PET insert, aimed at improving both patient feasibility and system performance for brain imaging. The designed PET/MR system includes two parts: the inside parts, including a radio frequency (RF) coil and PET ring, are mounted on patient’s head, and the outside part, a MR imager, is dependent of patient. The RF coil is the innermost layer, surrounded by an outer PET-ring layer. They are supported by a MRcompatible structure. And both RF coil and PET detectors are placed inside a standard clinical 3-T MR imager. From the design of the system we can infer that some advantages can be achieved. First, high sensitivity will be achieved with the same amount crystals as the PET ring is more close to region-of-interest area, at a reduced cost. Second, by using a 2-layer depth of interaction (DOI) detector, the parallax effect can be minimized. The resolution will benefit from short positron range caused by magnetic field and smaller ring diameter will also reduce the effect of non-collinearity. Thirdly, as the PET ring is mounted on head, impact of patient motion will be reduced.

Clinical value of PET/CT applied in diagnosis and treatment of malignant lymphoma%PET/CT应用于恶性淋巴瘤诊治中的临床价值

Institute of Scientific and Technical Information of China (English)

刘艳; 沈丽达; 杨小芸; 李蓉; 张晓芸

2016-01-01

Objective To investigate the clinical value of PET/CT in the diagnosis,clinical value,curative effect evalua-tion and residual lesion diagnosis of malignant lymphoma(ML). Methods Ono hundred and fifty-three cases of ML considered by PET/CT examination in the Yunnan Provincial Tumor Hospital from January 2008 to December 2013 were collected ,screened according to different research purposes ,grouped and statistically analyzed. Results The diagnosis positive rate of PET/CT was 96.08%(147/153). The maximal PET/CT standard uptake value (SUVmax) for diagnosing ML was 9.26-10.94,the mean SUV (ΔSUV) was 7.54-8.95.ΔSUV in the non-Hopdgkin lympghoma(NHL) group was higher than that in the Hodgkin lymphoma (HL) group,but the difference was not statistically significant(P<0.05);in 52 cases of preoperative PET/CT and CT combined with ultrasound examination,the clinical stage by CT combined with ultrasound examination in 16 cases were adjusted after PET/CT examination;ΔSUV had statistical difference between before and after treatment (P<0.05);in 34 cases of preoperative and post-operative PET/CT examination for evaluating the curative effects ,their curative effect judgments were consistent in 21 cases and inconsistent in 13 cases. Conclusion The PET/CT examination has high positive rate for diagnosing ML and may serve as a reli-able imagiological basis for clinically diagnosing lymphoma;the SUV value is an important indicator in the PET/CT examination;the PET/CT examination is an important means of the clinical staging and curative effect evaluation of ML ,which is not only used to judge the curative effect by the lesion size ,but also to assess the metabolic condition of residual lesion by the SUV value for guiding clinic to formulate the rational treatment scheme.%目的：探讨正电子发射型计算机断层显像（PET/CT）在恶性淋巴瘤诊断、临床价值、疗效评价及残留病灶诊断中的临床价值。方法收集云南省肿瘤医院2008年1�

Comparison of 11C-choline-PET/CT and whole body-MRI for staging of prostate cancer

International Nuclear Information System (INIS)

Eschmann, S.M.; Rieger, A.; Mueller, M.; Bares, R.; Pfannenberg, A.C.; Aschoff, P.; Claussen, C.D.; Schlemmer, H.P.; Paulsen, F.; Anastasiadis, A.

2007-01-01

Aim of this study was to compare the diagnostic accuracy of positron emission tomography and computed tomography with 11 C-Choline (Cho-PET/CT) and whole body magneticresonance imaging (WB-MRI) for diagnostic work-up of prostate cancer. Patients, methods: We evaluated retrospectively 42 patients with untreated prostate cancer (n =17), or increasing levels of prostate-specific antigen (PSA) after curative therapy (n = 25) who had been investigated by both Cho-PET/CT and WB-MRI. MRI, CT, and PET images were separately analyzed by experienced radiologists or nuclear medicine experts, followed by consensus reading. Validation was established by histology, follow-up, or consensus reading. Results: 88/103 detected lesions were considered as malignant: 44 bone metastases, 22 local tumor, 15 lymph node metastases, 3 lung, and 3 brain metastases. One further lesion was located in the adrenal gland, which was a second tumor. Overall sensitivity, specificity and accuracy for Cho-PET/CT were 96.6%, 76.5%, and 93.3%, resp., and for WB-MRI 78.4%, 94.1%, and 81.0%, resp. 3 vertebral metastases had initially been missed by Cho-PET/CT and were found retrospectively. MRI identified 2 bone metastases and 1 lymph node metastasis after being informed about the results of Cho-PET/CT. Conclusions: Cho-PET/CT and WB-MRI both presented high accuracy in the detection of bone and lymph node metastases. The strength of MRI is excellent image quality providing detailed anatomical information whereas the advantage of Cho-PET/CT is high image contrast of pathological foci. (orig.)

Effect of Attenuation Correction on Regional Quantification Between PET/MR and PET/CT

DEFF Research Database (Denmark)

Teuho, Jarmo; Johansson, Jarkko; Linden, Jani

2016-01-01

UNLABELLED: A spatial bias in brain PET/MR exists compared with PET/CT, because of MR-based attenuation correction. We performed an evaluation among 4 institutions, 3 PET/MR systems, and 4 PET/CT systems using an anthropomorphic brain phantom, hypothesizing that the spatial bias would be minimized....../MR systems, CTAC was applied as the reference method for attenuation correction. RESULTS: With CTAC, visual and quantitative differences between PET/MR and PET/CT systems were minimized. Intersystem variation between institutions was +3.42% to -3.29% in all VOIs for PET/CT and +2.15% to -4.50% in all VOIs...... for PET/MR. PET/MR systems differed by +2.34% to -2.21%, +2.04% to -2.08%, and -1.77% to -5.37% when compared with a PET/CT system at each institution, and these differences were not significant (P ≥ 0.05). CONCLUSION: Visual and quantitative differences between PET/MR and PET/CT systems can be minimized...

Integrated PET/MRI for whole-body staging of patients with primary cervical cancer: preliminary results

Energy Technology Data Exchange (ETDEWEB)

Grueneisen, Johannes; Kinner, Sonja; Forsting, Michael; Lauenstein, Thomas; Umutlu, Lale [University Hospital Essen, University of Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Schaarschmidt, Benedikt Michael [University Hospital Dusseldorf, University of Dusseldorf, Department of Diagnostic and Interventional Radiology, Dusseldorf (Germany); Heubner, Martin; Aktas, Bahriye [University Hospital Essen, University of Duisburg-Essen, Department of Obstetrics and Gynecology, Essen (Germany); Ruhlmann, Verena [University Hospital Essen, University of Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany)

2015-11-15

To assess the diagnostic value of integrated PET/MRI for whole-body staging of cervical cancer patients, as well as to investigate a potential association between PET/MRI derived functional parameters and prognostic factors of cervical cancer. The present study was approved by the local institutional review board. Twenty-seven patients with histopathologically confirmed cervical cancer were prospectively enrolled in our study. All patients underwent a whole-body PET/MRI examination after written informed consent was obtained. Two radiologists separately evaluated the PET/MRI data sets regarding the determination of local tumor extent of primary cervical cancer lesions, as well as detection of nodal and distant metastases. Furthermore, SUV and ADC values of primary tumor lesions were analyzed and correlated with dedicated prognostic factors of cervical cancer. Results based on histopathology and cross-sectional imaging follow-up served as the reference standard. PET/MRI enabled the detection of all 27 primary tumor lesions of the uterine cervix and allowed for the correct determination of the T-stage in 23 (85 %) out of the 27 patients. Furthermore, the calculated sensitivity, specificity and diagnostic accuracy for the detection of nodal positive patients (n = 11) were 91 %, 94 % and 93 %, respectively. PET/MRI correctly identified regional metastatic disease (N1-stage) in 8/10 (80 %) patients and non-regional lymph node metastases in 5/5 (100 %) patients. In addition, quantitative analysis of PET and MRI derived functional parameters (SUV; ADC values) revealed a significant correlation with pathological grade and tumor size (p < 0.05). The present study demonstrates the high potential of integrated PET/MRI for the assessment of primary tumor and the detection of lymph node metastases in patients with cervical cancer. Providing additional prognostic information, PET/MRI may serve as a valuable diagnostic tool for cervical cancer patients in a pretreatment setting

Integrated PET/MRI for whole-body staging of patients with primary cervical cancer: preliminary results

International Nuclear Information System (INIS)

Grueneisen, Johannes; Kinner, Sonja; Forsting, Michael; Lauenstein, Thomas; Umutlu, Lale; Schaarschmidt, Benedikt Michael; Heubner, Martin; Aktas, Bahriye; Ruhlmann, Verena

2015-01-01

To assess the diagnostic value of integrated PET/MRI for whole-body staging of cervical cancer patients, as well as to investigate a potential association between PET/MRI derived functional parameters and prognostic factors of cervical cancer. The present study was approved by the local institutional review board. Twenty-seven patients with histopathologically confirmed cervical cancer were prospectively enrolled in our study. All patients underwent a whole-body PET/MRI examination after written informed consent was obtained. Two radiologists separately evaluated the PET/MRI data sets regarding the determination of local tumor extent of primary cervical cancer lesions, as well as detection of nodal and distant metastases. Furthermore, SUV and ADC values of primary tumor lesions were analyzed and correlated with dedicated prognostic factors of cervical cancer. Results based on histopathology and cross-sectional imaging follow-up served as the reference standard. PET/MRI enabled the detection of all 27 primary tumor lesions of the uterine cervix and allowed for the correct determination of the T-stage in 23 (85 %) out of the 27 patients. Furthermore, the calculated sensitivity, specificity and diagnostic accuracy for the detection of nodal positive patients (n = 11) were 91 %, 94 % and 93 %, respectively. PET/MRI correctly identified regional metastatic disease (N1-stage) in 8/10 (80 %) patients and non-regional lymph node metastases in 5/5 (100 %) patients. In addition, quantitative analysis of PET and MRI derived functional parameters (SUV; ADC values) revealed a significant correlation with pathological grade and tumor size (p < 0.05). The present study demonstrates the high potential of integrated PET/MRI for the assessment of primary tumor and the detection of lymph node metastases in patients with cervical cancer. Providing additional prognostic information, PET/MRI may serve as a valuable diagnostic tool for cervical cancer patients in a pretreatment setting

Utility of F-18 FDG PET/CT on the evaluation of primary bone lymphoma.

Science.gov (United States)

Wang, Li-Juan; Wu, Hu-Bing; Wang, Meng; Han, Yan-Jiang; Li, Hong-Sheng; Zhou, Wen-Lan; Wang, Quan-Shi

2015-11-01

Primary bone lymphoma (PBL) is a rare type of malignant lymphoma. Few data have been reported regarding the utility of F-18 FDG PET/CT in this disease. The aim of this study was to assess the role of F-18 FDG PET/CT in the diagnosis and therapeutic effect evaluation of PBL. A total of 19 consecutive patients with PBL were enrolled. Whole-body PET/CT scan was performed for all patients. The diagnosis of PBL was established by histopathology and immunohistochemistry. F-18 FDG PET/CT was positive in 94.7% (18/19) of patients. Uptake of FDG in lesions was intense with SUVmax of 15.14 ± 11.82. Multiple involved lesions were found in 47.4% (9/19) patients, while 52.6% presented with a single involved lesion. Based on the lesions, PET detected 98.9% (87/88) lesions. Among them, 71.6% (63/88) lesions were found to be located in axial skeleton and 28.4% (25/88) in the extremity skeleton. FDG PET/CT also found the lesions infiltrate to the surrounding soft tissue in 84.2% (16/19) patients. On the syn-modality CT, the bone destruction was noted in 43.2% (38/88) of the lesions, of which 50.0% lesions presented as slight change in bone density and 50.0% as severe change. The diagnostic sensitivity of PET was much higher than that of CT (98.9% vs. 43.2%, P=0.000). PET/CT was performed for evaluation of treatment response in 13 patients. In 12 patients with complete response(CR), PET/CT found the 25 lesions were F-18 FDG fully resoluted after treatment, however, bone destruction was still presented in 72.0% (18/25) lesions. The present study suggests that F-18 FDG PET/CT was a sensitive imaging modality for diagnosis and treatment response evaluation of PBL. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Recurrent bladder carcinoma: clinical and prognostic role of 18 F-FDG PET/CT

Energy Technology Data Exchange (ETDEWEB)

Alongi, Pierpaolo [San Raffaele G. Giglio Institute, Department of Radiological Sciences, Nuclear Medicine Unit, Cefalu (Italy); Caobelli, Federico [Basel University Hospital, Department of Nuclear Medicine, Basel (Switzerland); Gentile, Roberta; Baldari, Sergio [University of Messina, Nuclear Medicine Unit, Department of Biomedical Sciences and Morphological and Functional Images, Messina (Italy); Stefano, Alessandro; Russo, Giorgio; Gilardi, Maria Carla [IBFM-CNR, Cefalu (Italy); Albano, Domenico [Universita degli Studi di Palermo, DIBIMEF - Sezione di Scienze Radiologiche, Palermo (Italy); Midiri, Massimo [San Raffaele G. Giglio Institute, Department of Radiological Sciences, Nuclear Medicine Unit, Cefalu (Italy); Universita degli Studi di Palermo, DIBIMEF - Sezione di Scienze Radiologiche, Palermo (Italy)

2017-02-15

A small number of studies evaluated the detection rate of lesions from bladder carcinoma (BC) of 18 F-FDG PET/CT in the restaging process. However, the prognostic role of FDG PET/CT still remains unclear. The aim of the present study was to evaluate the accuracy, the effect upon treatment decision, and the prognostic value of FDG PET/CT in patients with suspected recurrent BC. Forty-one patients affected by BC underwent FDG PET/CT for restaging purpose. The diagnostic accuracy of visually interpreted FDG PET/CT was assessed compared to histology (n = 8), other diagnostic imaging modalities (contrast-enhanced CT in 38/41 patients and MRI in 15/41) and clinical follow-up (n = 41). Semiquantitative PET values (SUVmax, SUVmean, SUL, MTV, TLG) were calculated using a graph-based method. Progression-free survival (PFS) and overall survival (OS) were assessed by using Kaplan-Meier curves. The risk of progression (hazard ratio, HR) was computed by Cox regression analysis by considering all the available variables. PET was considered positive in 21 of 41 patients. Of these, recurrent BC was confirmed in 20 (95 %). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FDG PET/CT were 87 %, 94 %, 95 %, 85 %, 90 %. AUC was 0.9 (95 %IC 0.8-1). Bayesian positive and negative likelihood ratios were 14.5 and 0.13, respectively. FDG PET/CT findings modified the therapeutic approach in 16 patients (modified therapy in 10 PET-positive patients, watch-and-wait in six PET-negative patients). PFS was significantly longer in patients with negative scan vs. those with pathological findings (85 % vs. 24 %, p < 0.05; HR = 12.4; p = 0.001). Moreover, an unremarkable study was associated with a longer OS (88 % vs. 47 % after 2 years and 87 % vs. 25 % after 3 years, respectively, p < 0.05). Standardized uptake value (SUV)max > 6 and total lesion glycolysis (TLG) > 8.5 were recognized as the most accurate thresholds to predict PFS (2-year PFS 62 % for

Quantitative PET imaging with the 3T MR-BrainPET

International Nuclear Information System (INIS)

Weirich, C.; Scheins, J.; Lohmann, P.; Tellmann, L.; Byars, L.; Michel, C.; Rota Kops, E.; Brenner, D.; Herzog, H.; Shah, N.J.

2013-01-01

The new hybrid imaging technology of MR-PET allows for simultaneous acquisition of versatile MRI contrasts and the quantitative metabolic imaging with PET. In order to achieve the quantification of PET images with minimal residual error the application of several corrections is crucial. In this work we present our results on quantification with the 3T MR BrainPET scanner

Brain PET scan

Science.gov (United States)

... results on a PET scan. Blood sugar or insulin levels may affect the test results in people with diabetes . PET scans may be done along with a CT scan. This combination scan is called a PET/CT. Alternative Names Brain positron emission tomography; PET scan - brain References Chernecky ...

Can FDG-PET/CT replace blind bone marrow biopsy of the posterior iliac crest in Ewing sarcoma?

International Nuclear Information System (INIS)

Kasalak, Oemer; Glaudemans, Andor W.J.M.; Overbosch, Jelle; Kwee, Thomas C.; Jutte, Paul C.

2018-01-01

To determine and compare the value of 18 F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) to blind bone marrow biopsy (BMB) of the posterior iliac crest in detecting metastatic bone marrow involvement in newly diagnosed Ewing sarcoma. This retrospective study included 20 patients with newly diagnosed Ewing sarcoma who underwent pretreatment FDG-PET/CT and a total of 38 blind BMBs (two unilateral and 18 bilateral) of the posterior iliac crest. FDG-PET/CT scans were evaluated for bone marrow involvement, both in the posterior iliac crest and other sites, and compared to blind BMB results. FDG-PET/CT was positive for bone marrow involvement in 7/38 posterior iliac crests, whereas BMB was positive in 5/38 posterior iliac crests. FDG-PET/CT and BMB results in the posterior iliac crest agreed in 36/38 cases (94.7%, 95% confidence interval [CI]: 82.7-98.5%). On a patient level, FDG-PET/CT was positive for bone marrow involvement in 4/20 patients, whereas BMB of the posterior iliac crest was positive in 3/20 patients. On a patient level, FDG-PET/CT and BMB results agreed in 19/20 patients (95.0%, 95% CI: 76.4-99.1%). The only discrepancies between FDG-PET/CT and BMB were observed in two BMBs of one patient. Both BMBs in this patient were negative, whereas FDG-PET/CT indicated bilateral posterior iliac crest involvement and also extensive bone marrow involvement elsewhere. FDG-PET/CT appears to be a valuable method for metastatic bone marrow assessment in newly diagnosed Ewing sarcoma. The routine use of blind BMB of the posterior iliac crest should be reconsidered when FDG-PET/CT is available. (orig.)

Can FDG-PET/CT replace blind bone marrow biopsy of the posterior iliac crest in Ewing sarcoma?

Energy Technology Data Exchange (ETDEWEB)

Kasalak, Oemer; Glaudemans, Andor W.J.M.; Overbosch, Jelle; Kwee, Thomas C. [University of Groningen, Department of Radiology, Nuclear Medicine and Molecular Imaging, University Medical Center Groningen (Netherlands); Jutte, Paul C. [University of Groningen, Department of Orthopedics, University Medical Center Groningen (Netherlands)

2018-03-15

To determine and compare the value of {sup 18}F-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) to blind bone marrow biopsy (BMB) of the posterior iliac crest in detecting metastatic bone marrow involvement in newly diagnosed Ewing sarcoma. This retrospective study included 20 patients with newly diagnosed Ewing sarcoma who underwent pretreatment FDG-PET/CT and a total of 38 blind BMBs (two unilateral and 18 bilateral) of the posterior iliac crest. FDG-PET/CT scans were evaluated for bone marrow involvement, both in the posterior iliac crest and other sites, and compared to blind BMB results. FDG-PET/CT was positive for bone marrow involvement in 7/38 posterior iliac crests, whereas BMB was positive in 5/38 posterior iliac crests. FDG-PET/CT and BMB results in the posterior iliac crest agreed in 36/38 cases (94.7%, 95% confidence interval [CI]: 82.7-98.5%). On a patient level, FDG-PET/CT was positive for bone marrow involvement in 4/20 patients, whereas BMB of the posterior iliac crest was positive in 3/20 patients. On a patient level, FDG-PET/CT and BMB results agreed in 19/20 patients (95.0%, 95% CI: 76.4-99.1%). The only discrepancies between FDG-PET/CT and BMB were observed in two BMBs of one patient. Both BMBs in this patient were negative, whereas FDG-PET/CT indicated bilateral posterior iliac crest involvement and also extensive bone marrow involvement elsewhere. FDG-PET/CT appears to be a valuable method for metastatic bone marrow assessment in newly diagnosed Ewing sarcoma. The routine use of blind BMB of the posterior iliac crest should be reconsidered when FDG-PET/CT is available. (orig.)

Clinical PET application

Energy Technology Data Exchange (ETDEWEB)

Lim, Sang Moo; Hong, Song W.; Choi, Chang W.; Yang, Seong Dae [Korea Cancer Center Hospital, Seoul (Korea)

1997-12-01

PET gives various methabolic images, and is very important, new diagnostic modality in clinical oncology. In Korea Cancer Center Hospital, PET is installed as a research tool of long-mid-term atomic research project. For the efficient use of PET for clinical and research projects, income from the patients should be managed to get the raw material, equipment, manpower, and also for the clinical PET research. 1. Support the clinical application of PET in oncology. 2. Budgetary management of income, costs for raw material, equipment, manpower, and the clinical PET research project. In this year, 250 cases of PET images were obtained, which resulted total income of 180,000,000 won. 50,000,000 won was deposited for the 1998 PET clinical research. Second year PET clinical research should be managed under unified project. Increased demand for {sup 18}FDG in and outside KCCH need more than 2 times production of {sup 18}FDG in a day purchase of HPLC pump and {sup 68}Ga pin source which was delayed due to economic crisis, should be done early in 1998. (author). 2 figs., 3 tabs.

PET and PET/CT in oncology: the key of diagnostic challenge

International Nuclear Information System (INIS)

Mortelmans, L.; Stroobants, S.; Spaepen, K.

2004-01-01

In this presentation authors present use of positron emission tomography (PET) in oncology. This lecture is divided to the following parts: (1) Assessment of treatment response; (2) Treatment monitoring by PET: clinical examples; (3) PET for early response assessment; (4) Use of PET in Radiotherapy planning

'PET -Compton' system. Comparative evaluation with PET system using Monte Carlo simulation

International Nuclear Information System (INIS)

Diaz Garcia, Angelina; Arista Romeu, Eduardo; Abreu Alfonso, Yamiel; Leyva Fabelo, Antonio; Pinnera Hernandez, Ibrahin; Bolannos Perez, Lourdes; Rubio Rodriguez, Juan A; Perez Morales, Jose M.; Arce Dubois, Pedro; Vela Morales, Oscar; Willmott Zappacosta, Carlos

2011-01-01

Positron Emission Tomography (PET) in small animals has actually achieved spatial resolution round about 1 mm and currently there are under study different approaches to improve this spatial resolution. One of them combines PET technology with Compton Cameras. This paper presents the idea of the so called 'PET-Compton' systems and includes comparative evaluation of spatial resolution and global efficiency in both PET and PET-Compton system by means of Monte Carlo simulations using Geant4 code. Simulation is done on a PET-Compton system consisting of LYSO-LuYAP scintillating detectors of particular small animal PET scanner named 'Clear-PET' and for Compton detectors based on CdZnTe semiconductor. A group of radionuclides that emits a positron (e + ) and γ quantum almost simultaneously and fulfills some selection criteria for their possible use in PET-Compton systems for medical and biological applications were studied under simulation conditions. (Author)

III Frontier of accurate diagnosis of breast cancer. 1. Present state and prospect of preoperative diagnosis of progression, differential diagnosis of benign and malign natures, and efficacy evaluation of neoadjuvant chemotherapy. 2) Clinical efficacy and problem of FDG-PET (PET/CT) in breast cancer

International Nuclear Information System (INIS)

Kitajima, Kazuhiro; Kaji, Yasushi; Hayashi, Mitsuhiro; Sunagawa, Masakatsu; Murakami, Kouji; Yamazaki, Erena

2008-01-01

On authors' experience and literature, clinical efficacy and limitation of fluorodeoxyglucose-positron emission tomography (FDG-PET) (PET/CT) in the breast cancer are described and discussed for detection of the primary lesion, preoperative staging and lymph node diagnosis, diagnosis of recurrence and remote metastasis, evaluation of therapeutic efficacy, and prediction of prognosis. For routine breast cancer screening, authors think PET/CT is not always effective because of many false positive/negative findings. PET/CT and subsequent CT with iodine contrast media are thought to be useful for preoperative staging and planning in conservative surgery though detection of micro-metastatic nodes are often difficult. PET is reportedly superior to 99m Tc-MDP scintigraphy in bone metastasis detection, but which conceivably depends on the nature (osteogenic/osteolytic) of the lesion. For recurrence and remote metastasis, the diagnostic sensitivity, specificity and accuracy of PET/CT are reported to be as high as 84-98, 84-94 and 86-97%, respectively. Standardization of PET/CT monitoring is now necessary to evaluate the therapeutic efficacy. SUV which indicates the degree of FDG accumulation in the lesion, can be used for prediction of prognosis in future. Awaited is the development of more effective PET/CT apparatus and agent (instead of FDG) for detection of small metastatic lesions, axillary lymphatic metastasis, and viable focus after therapeutic treatments. (R.T.)

(S)-4-(3-18F-fluoropropyl)-L-glutamic acid: an 18F-labeled tumor-specific probe for PET/CT imaging--dosimetry.

Science.gov (United States)

Smolarz, Kamilla; Krause, Bernd Joachim; Graner, Frank-Philipp; Wagner, Franziska Martina; Hultsch, Christina; Bacher-Stier, Claudia; Sparks, Richard B; Ramsay, Susan; Fels, Lüder M; Dinkelborg, Ludger M; Schwaiger, Markus

2013-06-01

The glutamic acid derivative (S)-4-(3-(18)F-Fluoropropyl)-l-glutamic acid ((18)F-FSPG, alias BAY 94-9392), a new PET tracer for the detection of malignant diseases, displayed promising results in non-small cell lung cancer patients. The aim of this study was to provide dosimetry estimates for (18)F-FSPG based on human whole-body PET/CT measurements. (18)F-FSPG was prepared by a fully automated 2-step procedure and purified by a solid-phase extraction method. PET/CT scans were obtained for 5 healthy volunteers (mean age, 59 y; age range, 51-64 y; 2 men, 3 women). Human subjects were imaged for up to 240 min using a PET/CT scanner after intravenous injection of 299 ± 22.5 MBq of (18)F-FSPG. Image quantification, time-activity data modeling, estimation of normalized number of disintegrations, and production of dosimetry estimates were performed using the RADAR (RAdiation Dose Assessment Resource) method for internal dosimetry and in general concordance with the methodology and principles as presented in the MIRD 16 document. Because of the renal excretion of the tracer, the absorbed dose was highest in the urinary bladder wall and kidneys, followed by the pancreas and uterus. The individual organ doses (mSv/MBq) were 0.40 ± 0.058 for the urinary bladder wall, 0.11 ± 0.011 for the kidneys, 0.077 ± 0.020 for the pancreas, and 0.030 ± 0.0034 for the uterus. The calculated effective dose was 0.032 ± 0.0034 mSv/MBq. Absorbed dose to the bladder and the effective dose can be reduced significantly by frequent bladder-voiding intervals. For a 0.75-h voiding interval, the bladder dose was reduced to 0.10 ± 0.012 mSv/MBq, and the effective dose was reduced to 0.015 ± 0.0010 mSv/MBq. On the basis of the distribution and biokinetic data, the determined radiation dose for (18)F-FSPG was calculated to be 9.5 ± 1.0 mSv at a patient dose of 300 MBq, which is of similar magnitude to that of (18)F-FDG (5.7 mSv). The effective dose can be reduced to 4.5 ± 0.30 mSv (at 300 MBq

PET-COMPTON System. Comparative evaluation with PET System using Monte Carlo Simulation

International Nuclear Information System (INIS)

Diaz Garcia, Angelina; Arista Romeu, Eduardo; Abreu Alfonso, Yamiel; Leyva Fabelo, Antonio; Pinnera HernAndez, Ibrahin; Bolannos Perez, Lourdes; Rubio Rodriguez, Juan A.; Perez Morales, Jose M.; Arce Dubois, Pedro; Vela Morales, Oscar; Willmott Zappacosta, Carlos

2012-01-01

Positron Emission Tomography (PET) in small animals has actually achieved spatial resolution round about 1 mm and currently there are under study different approaches to improve this spatial resolution. One of them combines PET technology with Compton Cameras. This paper presents the idea of the so called PET-Compton systems and has included comparative evaluation of spatial resolution and global efficiency in both PET and PET-Compton system by means of Monte Carlo simulations using Geant4 code. Simulation was done on a PET-Compton system made-up of LYSO-LuYAP scintillating detectors of particular small animal PET scanner named Clear-PET and for Compton detectors based on CdZnTe semiconductor. A group of radionuclides that emits a positron (e+) and quantum almost simultaneously and fulfills some selection criteria for their possible use in PET-Compton systems for medical and biological applications were studied under simulation conditions. By means of analytical reconstruction using SSRB (Single Slide Rebinning) method were obtained superior spatial resolution in PET-Compton system for all tested radionuclides (reaching sub-millimeter values of for 22Na source). However this analysis done by simulation have shown limited global efficiency values in PET-Compton system (in the order of 10 -5 -10 -6 %) instead of values around 5*10 -1 % that have been achieved in PET system. (author)

Volume-based quantitative FDG PET/CT metrics and their association with optimal debulking and progression-free survival in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery

Energy Technology Data Exchange (ETDEWEB)

Vargas, H.A.; Burger, I.A.; Micco, M.; Sosa, R.E.; Weber, W.; Hricak, H.; Sala, E. [Memorial Sloan Kettering Cancer Center, Department of Radiology, New York, NY (United States); Goldman, D.A. [Memorial Sloan Kettering Cancer Center, Department of Epidemiology and Biostatistics, New York, NY (United States); Chi, D.S. [Memorial Sloan Kettering Cancer Center, Department of Surgery, New York, NY (United States)

2015-11-15

Our aim was to evaluate the associations between quantitative {sup 18}F-fluorodeoxyglucose positron-emission tomography (FDG-PET) uptake metrics, optimal debulking (OD) and progression-free survival (PFS) in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery. Fifty-five patients with recurrent ovarian cancer underwent FDG-PET/CT within 90 days prior to surgery. Standardized uptake values (SUV{sub max}), metabolically active tumour volumes (MTV), and total lesion glycolysis (TLG) were measured on PET. Exact logistic regression, Kaplan-Meier curves and the log-rank test were used to assess associations between imaging metrics, OD and PFS. MTV (p = 0.0025) and TLG (p = 0.0043) were associated with OD; however, there was no significant association between SUV{sub max} and debulking status (p = 0.83). Patients with an MTV above 7.52 mL and/or a TLG above 35.94 g had significantly shorter PFS (p = 0.0191 for MTV and p = 0.0069 for TLG). SUV{sub max} was not significantly related to PFS (p = 0.10). PFS estimates at 3.5 years after surgery were 0.42 for patients with an MTV ≤ 7.52 mL and 0.19 for patients with an MTV > 7.52 mL; 0.46 for patients with a TLG ≤ 35.94 g and 0.15 for patients with a TLG > 35.94 g. FDG-PET metrics that reflect metabolic tumour burden are associated with optimal secondary cytoreductive surgery and progression-free survival in patients with recurrent ovarian cancer. (orig.)

Comparison of dosimetry between PET/CT and PET alone using 11C-ITMM

International Nuclear Information System (INIS)

Ito, Kimiteru; Sakata, Muneyuki; Wagarsuma, Kei; Toyohara, Jun; Ishibashi, Kenji; Ishii, Kenji; Ishiwata, Kiichi; Oda, Keiichi

2016-01-01

We used a new tracer, N-[4-[6-(isopropylamino) pyrimidin-4-yl]-1,3-thiazol-2-yl]-4- 11 C-methoxy-N-methylbenzamide ( 11 C-ITMM), to compare radiation doses from positron emission tomography (PET)/computed tomography (CT) with previously published doses from PET alone. Twelve healthy volunteers [six males (mean age ± SD, 27.7 ± 6.7 years) and six females (31.8 ± 14.5 years)] in 12 examinations were recruited. Dose estimations from PET/CT were compared with those from PET alone. Regions of interest (ROIs) in PET/CT were delineated on the basis of low-dose CT (LD-CT) images acquired during PET/CT. Internal and external radiation doses were estimated using OLINDA/EXM 1.0 and CT-Expo software. The effective dose (ED) for 11 C-ITMM calculated from PET/CT was estimated to be 4.7 ± 0.5 μSv/MBq for the male subjects and 4.1 ± 0.7 μSv/MBq for the female subjects. The mean ED for 11 C-ITMM calculated from PET alone in a previous report was estimated to be 4.6 ± 0.3 μSv/MBq (males, n = 3). The ED values for 11 C-ITMM calculated from PET/CT in the male subjects were almost identical to those from PET alone. The absorbed doses (ADs) of the gallbladder, stomach, red bone marrow, and spleen calculated from PET/CT were significantly different from those calculated from PET alone. The EDs of 11 C-ITMM calculated from PET/CT were almost identical to those calculated from PET alone. The ADs in several organs calculated from PET/CT differed from those from PET alone. LD-CT images acquired during PET/CT may facilitate organ identification.

Additional value of PET-CT in the staging of lung cancer: comparison with CT alone, PET alone and visual correlation of PET and CT

International Nuclear Information System (INIS)

Wever, W. de; Marchal, G.; Bogaert, J.; Verschakelen, J.A.; Ceyssens, S.; Mortelmans, L.; Stroobants, S.

2007-01-01

Integrated positron emission tomography (PET) and computed tomography (CT) is a new imaging modality offering anatomic and metabolic information. The purpose was to evaluate retrospectively the accuracy of integrated PET-CT in the staging of a suggestive lung lesion, comparing this with the accuracy of CT alone, PET alone and visually correlated PET-CT. Fifty patients undergoing integrated PET-CT for staging of a suggestive lung lesion were studied. Their tumor, node, metastasis (TNM) statuses were determined with CT, PET, visually correlated PET-CT and integrated PET-CT. These TNM stages were compared with the surgical TNM status. Integrated PET-CT was the most accurate imaging technique in the assessment of the TNM status. Integrated PET-CT predicted correctly the T status, N status, M status and TNM status in, respectively, 86%, 80%, 98%, 70% versus 68%, 66%,88%, 46% with CT, 46%, 70%, 96%, 30% with PET and 72%, 68%, 96%, 54% with visually correlated PET-CT. T status and N status were overstaged, respectively, in 8% and 16% with integrated PET-CT, in 20% and 28% with CT, in 16% and 20% with PET, in 12% and 20% with visually correlated PET-CT and understaged in 6% and 4% with integrated PET-CT, versus 12% and 6% with CT, 38% and 10% with PET and 12% with visually correlated PET-CT. Integrated PET-CT improves the staging of lung cancer through a better anatomic localization and characterization of lesions and is superior to CT alone and PET alone. If this technique is not available, visual correlation of PET and CT can be a valuable alternative. (orig.)

Pet-Related Infections.

Science.gov (United States)

Day, Michael J

2016-11-15

Physicians and veterinarians have many opportunities to partner in promoting the well-being of people and their pets, especially by addressing zoonotic diseases that may be transmitted between a pet and a human family member. Common cutaneous pet-acquired zoonoses are dermatophytosis (ringworm) and sarcoptic mange (scabies), which are both readily treated. Toxoplasmosis can be acquired from exposure to cat feces, but appropriate hygienic measures can minimize the risk to pregnant women. Persons who work with animals are at increased risk of acquiring bartonellosis (e.g., cat-scratch disease); control of cat fleas is essential to minimize the risk of these infections. People and their pets share a range of tick-borne diseases, and exposure risk can be minimized with use of tick repellent, prompt tick removal, and appropriate tick control measures for pets. Pets such as reptiles, amphibians, and backyard poultry pose a risk of transmitting Salmonella species and are becoming more popular. Personal hygiene after interacting with these pets is crucial to prevent Salmonella infections. Leptospirosis is more often acquired from wildlife than infected dogs, but at-risk dogs can be protected with vaccination. The clinical history in the primary care office should routinely include questions about pets and occupational or other exposure to pet animals. Control and prevention of zoonoses are best achieved by enhancing communication between physicians and veterinarians to ensure patients know the risks of and how to prevent zoonoses in themselves, their pets, and other people.

PET and PET-CT. State of the art and future prospects

International Nuclear Information System (INIS)

Fanti, Stefano; Franchi, Roberto; Battista, Giuseppe; Monetti, Nino; Canini, Romeo

2005-01-01

Fluoro-deoxyglucose positron emission tomography (FDG PET) enables the in vivo study of tissue metabolism, and thus is able to identify malignant tumours as hypermetabolic lesions by an increase in tracer uptake. Many papers have demonstrated both the relevant impact of FDG PET on staging of many cancers and the superior accuracy of the technique compared with conventional diagnostic methods for pre-treatment evaluation, therapy response evaluation and relapse identification. In particular PET was found useful in identifying lymph nodal and metastatic spread. thus altering patient management in more than 30% of cases. PET images, however, provide limited anatomical data, which in regions such as the head and neck, mediastinum and pelvic cavity is a significant drawback. The exact localization of lesions may also be difficult in some cases, on the basis of PET images alone. The introduction of combined PET-computed tomography (PET-CT) scanners enables the almost simultaneous acquisition of transmission and emission images, thus obtaining optimal fusion images in a very short time. PET-CT fusion images enable lesions to be located, reducing false positive studies and increasing accuracy; the overall duration of examination may also be reduced. On the basis of both literature data and our experience we established the clinical indications when PET-CT may be particularly useful, in comparison with PET alone. It should also be underlined that the use of PET-CT is almost mandatory for new traces such as C-choline and C-methionine; these new tracers may be applied for studying tumours not assessable with FDG, such as prostate cancer. In conclusion PET-CT is at present the most advanced method for metabolic imaging, and is capable of precisely localizing and assessing tumours; fusion images reduce false positive and inconclusive studies, thus increasing diagnostic accuracy [it

Development of PET insert for simultaneous PET/MR imaging of human brain

Energy Technology Data Exchange (ETDEWEB)

Jung, Jiwoong; Choi, Yong; Jung, Jin Ho; Kim, Sangsu; Im, Ki Chun; Lim, Hyun Keong [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Oh, Changheun; Park, HyunWook; Cho, Gyuseong [Departments of Electrical Engineering and Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of)

2014-07-29

Recently, there has been great interest on the development of combined PET/MR, which is a useful tool for both functional and anatomic imaging. The purpose of this study was to develop a MR compatible PET insert for simultaneous PET and MR imaging of human brain and to evaluate the performance of the hybrid PET-MRI. The PET insert consisted of 18 detector blocks arranged in a ring of 390 mm diameter with 60 mm axial FOV. Each detector block was composed of 4 × 4 matrix of detector modules, each of which consisted of a 4 × 4 array LYSO coupled to a 4 × 4 GAPD array. The PET gantry was shielded with gold-plated conductive fabric tapes. The charge signals of PET detector transferred via 4 m long flat cables were fed into the position decoder circuits (PDCs) and then transferred to FPGA-embedded DAQ modules. The PDCs and DAQ modules were enclosed in an aluminum box and located at the rear of the MR bore inside MRI room. 3-T human MRIs of two different vendors were used to evaluate the MR compatibility of developed PET insert. No significant changes of the PET performance and the homogeneity of MR images caused by the non-compatibility of PET-MRI were observed with the 2 different MRIs. The signal intensities of MR images were slightly degraded (<3.6%) with the both MRI systems. The difference between independently and simultaneously acquired PET images of brain phantom was negligibly small (<4.3%). High quality simultaneous brain PET and MRI of 3 normal volunteers were successfully acquired. Experimental results indicate that the high performance compact and lightweight PET insert for hybrid PET/MRI, which could be utilized with the MRI from various manufactures, can be developed using GAPD arrays and charge signal transmission method proposed in this study.

Role of pharmacokinetic parameters derived with high temporal resolution DCE MRI using simultaneous PET/MRI system in breast cancer: A feasibility study

Energy Technology Data Exchange (ETDEWEB)

Jena, Amarnath, E-mail: drjena2002@gmail.com [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India); Taneja, Sangeeta; Singh, Aru; Negi, Pradeep; Mehta, Shashi Bhushan [Department of Molecular Imaging and Nuclear Medicine, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India); Sarin, Ramesh [Department of Surgical Oncology, Indraprastha Apollo Hospitals, Sarita Vihar, Delhi–Mathura Road, New Delhi 110076 (India)

2017-01-15

Highlights: • Simultaneous PET/MRI (with 3T MRI in the core) for quantitative pharmacokinetics. • Diagnostic accuracy of pharmacokinetic parameters like K{sup trans}, K{sub ep} and v{sub e} acquired through this system. • Incorporating high temporal resolution sequence with short acquisition time of 60 s within the routine DCE MRI in a simultaneous PET/MRI system. - Abstract: Purpose: To evaluate the reliability of pharmacokinetic parameters like K{sup trans}, Kep and v{sub e} derived through DCE MRI breast protocol using 3 T Simultaneous PET/MRI (3 Tesla Positron Emission Tomography/Magnetic Resonance Imaging) system in distinguishing benign and malignant lesions. Materials and methods: High temporal resolution DCE (Dynamic Contrast Enhancement) MRI performed as routine breast MRI for diagnosis or as a part of PET/MRI for cancer staging using a 3 T simultaneous PET/MRI system in 98 women having 109 breast lesions were analyzed for calculation of pharmacokinetic parameters (K{sup trans}, v{sub e}, and Kep) at 60 s time point using an in-house developed computation scheme. Results: Receiver operating characteristic (ROC) curve analysis revealed a cut off value for K{sup trans}, Kep, v{sub e} as 0.50, 2.59, 0.15 respectively which reliably distinguished benign and malignant breast lesions. Data analysis revealed an overall accuracy of 94.50%, 79.82% and 87.16% for K{sup trans}, Kep, v{sub e} respectively. Introduction of native T1 normalization with an externally placed phantom showed a higher accuracy (94.50%) than without native T1 normalization (93.50%) with an increase in specificity of 87% vs 84%. Conclusion: Overall the results indicate that reliable measurement of pharmacokinetic parameters with reduced acquisition time is feasible in a 3TMRI embedded PET/MRI system with reasonable accuracy and application may be extended to exploit the potential of simultaneous PET/MRI in further work on breast cancer.

PET/MRI and PET/CT in advanced gynaecological tumours: initial experience and comparison

Energy Technology Data Exchange (ETDEWEB)

Queiroz, Marcelo A.; Schulthess, Gustav von; Veit-Haibach, Patrick [University Hospital Zurich, Department Medical Radiology, Nuclear Medicine, Zurich (Switzerland); University Hospital Zurich, Department Medical Radiology, Diagnostic and Interventional Radiology, Zurich (Switzerland); University of Zurich, Zurich (Switzerland); Kubik-Huch, Rahel A.; Freiwald-Chilla, Bianka [Kantonsspital Baden AG, Department of Radiology, Baden (Switzerland); Hauser, Nik [Kantonsspital Baden AG, Department of Gynaecology, Baden (Switzerland); Froehlich, Johannes M. [Guerbet AG, Zurich (Switzerland)

2015-08-15

To compare the diagnostic accuracy of PET/MRI and PET/CT for staging and re-staging advanced gynaecological cancer patients as well as identify the potential benefits of each method in such a population. Twenty-six patients with suspicious or proven advanced gynaecological cancer (12 ovarian, seven cervical, one vulvar and four endometrial tumours, one uterine metastasis, and one primary peritoneal cancer) underwent whole-body imaging with a sequential trimodality PET/CT/MR system. Images were analysed regarding primary tumour detection and delineation, loco-regional lymph node staging, and abdominal/extra-abdominal distant metastasis detection (last only by PET/CT). Eighteen (69.2 %) patients underwent PET/MRI for primary staging and eight patients (30.8 %) for re-staging their gynaecological malignancies. For primary tumour delineation, PET/MRI accuracy was statistically superior to PET/CT (p < 0.001). Among the different types of cancer, PET/MRI presented better tumour delineation mainly for cervical (6/7) and endometrial (2/3) cancers. PET/MRI for local evaluation as well as PET/CT for extra-abdominal metastases had therapeutic consequences in three and one patients, respectively. PET/CT detected 12 extra-abdominal distant metastases in 26 patients. PET/MRI is superior to PET/CT for primary tumour delineation. No differences were found in detection of regional lymph node involvement and abdominal metastases detection. (orig.)

Comparative analysis of PET/CT and PET/MR image characteristics of head and neck squamous cell carcinoma%对比分析头颈部鳞状细胞癌PET/CT与PET/MR特征

Institute of Scientific and Technical Information of China (English)

白乐; 程勇; 唐勇进; 凌雪英

2017-01-01

Objective To investigate PET/CT and PET/MR characteristics of head and neck squamous cell carcinoma (HNSCC).Methods Totally 40 patients with HNSCC underwent whole body 18F-FDG PET/CT and MR scans of head and neck before anti-tumor treatment.PET positive lesions of HNSCC,including primary lesions and lymph nodes were evaluated by 2 radiologists independently.Then the imaging quality,fusion quality,lesion conspicuity and lesion characteristics were assessed based on PET/CT,PET/MR T1WI and PET/MR T2WI.Results Ninety PET positive lesions in all 40patients were evaluated,including 40 primary lesions and 50 lymph nodes.Similar imaging quality and fusion quality of PET/CT,PET/MR T1WI and PET/MR T2WI were obtained without statistical difference (both P＞0.05).For the lesion conspicuity,PET/MR T1WI and PET/MR T2WI demonstrated significantly better than PET/CT in positive primary lesions and lymph nodes (all P＜0.05).For the characteristics of positive primary lesions,PET/MR T2WI provided more information than PET/CT in 29 lesions,equal to PET/CT in 4 lesions,and less than PET/CT in 7 lesions.Conclusion The application of PET/MR in HNSCC is feasible,being superior to PET/CT in indication of lesions in head and neck area.%目的 探讨头颈部鳞状细胞癌(HNSCC)的PET/CT及PET/MR特征.方法 纳入未经抗肿瘤治疗的头颈部鳞状细胞癌患者40例,所有患者均接受PET/CT及头颈部MR检查.由2名观察者独立观察PET阳性病灶,包括阳性原发灶及阳性淋巴结;并对PET/CT、PET/MR T1WI及PET/MR T2WI的图像质量、融合准确度、病灶清晰度、病灶特征等进行评分.分析2名观察者间的一致性.结果 40例患者共90个PET阳性病灶,包括阳性原发灶40个、阳性淋巴结50个.PET/CT、PET/MR T1WI及PET/MR T2WI在图像质量及融合准确度方面差异均无统计学意义(P均＞0.05);在显示阳性原发灶及阳性淋巴结的清晰度方面,PET/MR T1WI及PET/MR T2WI均优于PET/CT(P均＜0.05).40个阳性原发灶中,PET

Present and future of PET and PET/CT in gynaecologic malignancies

International Nuclear Information System (INIS)

Musto, Alessandra; Rampin, Lucia; Nanni, Cristina; Marzola, Maria Cristina; Fanti, Stefano; Rubello, Domenico

2011-01-01

Objectives: To review the published data in literature on patients affected by gynaecological malignancies to establish the role of 18 F-FDG positron emission tomography (PET) and PET/CT in comparison to conventional imaging (CI). Materials and methods: All papers specifically addressed to the role of 18 F-FDG PET and PET/CT in gynaecological malignancies published on PubMed/Medline, in abstracts from the principal international congresses, in the guidelines from national Societies that had appeared in literature until November 2009 were considered for the purpose of the present study. Results and conclusions: The use of 18 F-FDG PET, and even more of 18 F-FDG PET/CT, is increasing in the follow up of patients with gynaecologic malignancies and suspected recurrent disease: there is evidence in the literature that 18 F-FDG PET/CT has a higher sensitivity than CI in depicting occult metastatic spread. An interesting issue is represented by patients with ovarian cancer with an increase of the specific biomarker, CA-125, and negative/inconclusive findings at CI. The use of 18 F-FDG PET in differential diagnosis and staging is more controversial, but there is some evidence that a baseline PET examination performed before commencing therapy, for staging purpose, is also useful to evaluate the response to chemoradiation treatment. In several papers it has been suggested a relevant role of 18 F-FDG PET/CT in evaluating the entity of response to treatment and therefore to plan the subsequent therapeutic strategy.

Experience with PET FDG - Preliminary analysis

International Nuclear Information System (INIS)

Massardo, Teresa; Jofre, Josefina; Canessa, Jose; Gonzalez, Patricio; Humeres, Pamela; Sierralta, Paulina; Galaz, Rodrigo; Miranda, Karina

2004-01-01

Full text: The objective of this preliminary communication was to analyse the indications and data in initial group of patients studied with first dedicated PET scanner in the country at Hospital Militar in Santiago Chile. The main application of positron emission tomography (PET) with 18-Fluoro deoxyglucose (FDG) is related with oncological patients management. We studied 136 patients, 131 (97%) with known or suspected malignant disease and remaining 5 for cardiological or neuropsychiatric disease. Ten patients were controlled diabetics (1 insulin dependent). Their mean age was 51.6±18 years ranging from 6 to 84 years and 65% were females. A total of 177 scans were acquired using a dedicated PET (Siemens HR + with 4mm resolution) system. Mean F18-FDG injected dose was 477±107 MBq (12.9±2.9 mCi). Mean blood glucose levels, performed prior the injection, were 94±17mg/dl (range 62-161). F18-FDG was obtained from the cyclotron IBA Cyclone 18/9 installed in the Chilean Agency of Nuclear Energy, distant about 15 miles away from the clinical PET facility. PET studies were analyzed by at least 4 independent observers visually. Standardized uptake value (SUV) was calculated in some cases. Image fusion of FDG images with recent anatomical (CT, MRI) studies was performed where available. Data acquisition protocol consisted in 7-8 beds/study from head to mid-thighs, with 6-7-min/bed acquisitions, 36% transmission with germanium 68 rods. Data was reconstructed with standard OSEM protocol. The main indications included pulmonary lesions in 31%, gastrointestinal cancers in 21%, melanoma in 13% and lymphoma in 9% patients. The remaining were of breast, thyroid, testes, ovary, musculoskeletal (soft tissue and bone), brain tumour etc. Abnormal focal tracer uptake was observed in 83/131 oncological patients, 54% corroborating with clinical diagnosis of primary tumor or recurrence while 46% showed new metastatic localization. FDG scans were normal 36/131 patients. In 9 patients

Experience with PET FDG - Preliminary analysis

Energy Technology Data Exchange (ETDEWEB)

Massardo, Teresa; Jofre, Josefina; Canessa, Jose; Gonzalez, Patricio; Humeres, Pamela; Sierralta, Paulina; Galaz, Rodrigo; Miranda, Karina [Centro PET de Imagenes Moleculares, Hospital Militar de Santiago, Santiago (Chile)

2004-01-01

Full text: The objective of this preliminary communication was to analyse the indications and data in initial group of patients studied with first dedicated PET scanner in the country at Hospital Militar in Santiago Chile. The main application of positron emission tomography (PET) with 18-Fluoro deoxyglucose (FDG) is related with oncological patients management. We studied 136 patients, 131 (97%) with known or suspected malignant disease and remaining 5 for cardiological or neuropsychiatric disease. Ten patients were controlled diabetics (1 insulin dependent). Their mean age was 51.6{+-}18 years ranging from 6 to 84 years and 65% were females. A total of 177 scans were acquired using a dedicated PET (Siemens HR + with 4mm resolution) system. Mean F18-FDG injected dose was 477{+-}107 MBq (12.9{+-}2.9 mCi). Mean blood glucose levels, performed prior the injection, were 94{+-}17mg/dl (range 62-161). F18-FDG was obtained from the cyclotron IBA Cyclone 18/9 installed in the Chilean Agency of Nuclear Energy, distant about 15 miles away from the clinical PET facility. PET studies were analyzed by at least 4 independent observers visually. Standardized uptake value (SUV) was calculated in some cases. Image fusion of FDG images with recent anatomical (CT, MRI) studies was performed where available. Data acquisition protocol consisted in 7-8 beds/study from head to mid-thighs, with 6-7-min/bed acquisitions, 36% transmission with germanium 68 rods. Data was reconstructed with standard OSEM protocol. The main indications included pulmonary lesions in 31%, gastrointestinal cancers in 21%, melanoma in 13% and lymphoma in 9% patients. The remaining were of breast, thyroid, testes, ovary, musculoskeletal (soft tissue and bone), brain tumour etc. Abnormal focal tracer uptake was observed in 83/131 oncological patients, 54% corroborating with clinical diagnosis of primary tumor or recurrence while 46% showed new metastatic localization. FDG scans were normal 36/131 patients. In 9

33 CFR 100.919 - International Bay City River Roar, Bay City, MI.

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2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false International Bay City River Roar, Bay City, MI. 100.919 Section 100.919 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Bay City River Roar, Bay City, MI. (a) Regulated Area. A regulated area is established to include all...

Head and neck imaging with PET and PET/CT: artefacts from dental metallic implants

International Nuclear Information System (INIS)

Goerres, Gerhard W.; Hany, Thomas F.; Kamel, Ehab; Schulthess von, Gustav K.; Buck, Alfred

2002-01-01

Germanium-68 based attenuation correction (PET Ge68 ) is performed in positron emission tomography (PET) imaging for quantitative measurements. With the recent introduction of combined in-line PET/CT scanners, CT data can be used for attenuation correction. Since dental implants can cause artefacts in CT images, CT-based attenuation correction (PET CT ) may induce artefacts in PET images. The purpose of this study was to evaluate the influence of dental metallic artwork on the quality of PET images by comparing non-corrected images and images attenuation corrected by PET Ge68 and PET CT . Imaging was performed on a novel in-line PET/CT system using a 40-mAs scan for PET CT in 41 consecutive patients with high suspicion of malignant or inflammatory disease. In 17 patients, additional PET Ge68 images were acquired in the same imaging session. Visual analysis of fluorine-18 fluorodeoxyglucose (FDG) distribution in several regions of the head and neck was scored on a 4-point scale in comparison with normal grey matter of the brain in the corresponding PET images. In addition, artefacts adjacent to dental metallic artwork were evaluated. A significant difference in image quality scoring was found only for the lips and the tip of the nose, which appeared darker on non-corrected than on corrected PET images. In 33 patients, artefacts were seen on CT, and in 28 of these patients, artefacts were also seen on PET imaging. In eight patients without implants, artefacts were seen neither on CT nor on PET images. Direct comparison of PET Ge68 and PET CT images showed a different appearance of artefacts in 3 of 17 patients. Malignant lesions were equally well visible using both transmission correction methods. Dental implants, non-removable bridgework etc. can cause artefacts in attenuation-corrected images using either a conventional 68 Ge transmission source or the CT scan obtained with a combined PET/CT camera. We recommend that the non-attenuation-corrected PET images also be

Standardised uptake values from PET/CT images: comparison with conventional attenuation-corrected PET

International Nuclear Information System (INIS)

Souvatzoglou, M.; Ziegler, S.I.; Martinez, M.J.; Dzewas, G.; Schwaiger, M.; Bengel, F.; Busch, R.

2007-01-01

In PET/CT, CT-derived attenuation factors may influence standardised uptake values (SUVs) in tumour lesions and organs when compared with stand-alone PET. Therefore, we compared PET/CT-derived SUVs intra-individually in various organs and tumour lesions with stand-alone PET-derived SUVs. Thirty-five patients with known or suspected cancer were prospectively included. Sixteen patients underwent FDG PET using an ECAT HR+scanner, and subsequently a second scan using a Biograph Sensation 16PET/CT scanner. Nineteen patients were scanned in the reverse order. All images were reconstructed with an iterative algorithm (OSEM). Suspected lesions were grouped as paradiaphragmatic versus distant from the diaphragm. Mean and maximum SUVs were also calculated for brain, lung, liver, spleen and vertebral bone. The attenuation coefficients (μ values) used for correction of emission data (bone, soft tissue, lung) in the two data sets were determined. A body phantom containing six hot spheres and one cold cylinder was measured using the same protocol as in patients. Forty-six lesions were identified. There was a significant correlation of maximum and mean SUVs derived from PET and PET/CT for 14 paradiaphragmatic lesions (r=0.97 respectively; p<0.001 respectively) and for 32 lesions located distant from the diaphragm (r=0.87 and r=0.89 respectively; p<0.001 respectively). No significant differences were observed in the SUVs calculated with PET and PET/CT in the lesions or in the organs. In the phantom, radioactivity concentration in spheres calculated from PET and from PET/CT correlated significantly (r=0.99; p<0.001). SUVs of cancer lesions and normal organs were comparable between PET and PET/CT, supporting the usefulness of PET/CT-derived SUVs for quantification of tumour metabolism. (orig.)

Evaluation Value of Invasion Area PET-CT Scanning for Chemotherapeutic Efficacy and Prognosis of Patients with Lymphoma%受侵区域PET-CT扫描对淋巴瘤化疗疗效及预后评估价值分析

Institute of Scientific and Technical Information of China (English)

王洁; 庞华; 敬兴果; 段东; 许璐

2016-01-01

目的:探讨受侵区域PET-CT扫描对淋巴瘤化疗疗效及预后评估的价值.方法:2012年5月至2015年1月本院收治的98例初诊淋巴瘤患者采用R-CHOP方案化疗,在化疗6个周期后行全身和受侵区域的PET-CT扫描.按照化疗前PET-CT扫描结果确定受侵区域,比较全身和受侵区域PET-CT扫描在临床分期、疗效评价、辐射剂量、扫描时间等方面的差异.结果:全身与受侵区域PET-CT临床分期结果完全一致,全身和受侵区域PET-CT临床分期与Ann Arbor临床分期符合率为95.9％ (94/98).全身PET-CT扫描显示CR 68例,PR 26例,SD 1例,PD 3例,受侵犯区域PET-CT扫描显示CR 68例,PR 24例,SD 2例,PD 4例,全身和受侵区域PET-CT扫描对CR的评价一致.在68例CR患者中受侵区域PET-CT扫描CT、PET、PET-CT辐射剂量显著低于全身PET-CT扫描,扫描时间均显著少于全身PET-CT(P ＜0.05).结论:化疗后临床疗效为CR患者受侵区域PET-CT扫描结果与全身PET-CT扫描一致,并能够显著降低辐射剂量和扫描时间;对于疗效为PR、SD、PD患者,则应行全身PET-CT扫描评价疗效.

Clinical Usefulness of F-18 FDG PET/CT in papillary thyroid cancer with negative radioiodine scan and elevated thyroglobulin level or positive anti-thyroglobulin antibody

Energy Technology Data Exchange (ETDEWEB)

Choi, Su Jung; Jung, Kyung Pyo; Lee, Sun Seong; Park, Yun Soo; Lee, Seok Mo [Dept. of Nuclear Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Bae, Sang Kyun [Dept. of Nuclear Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

2016-06-15

Elevated thyroglobulin (Tg) levels, along with a negative radioiodine scan, present a clinical problem for the diagnosis of recurrence in papillary thyroid cancer (PTC) patients. The purpose of this study was to assess (1) the usefulness of 18F-fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET)/computed tomography (CT) for PTC patients with negative diagnostic radioiodine scan and elevated serum Tg level or positive anti-thyroglobulin antibody (TgAb), and (2) the effect of endogenous thyroid stimulating hormone (TSH) stimulation (ETS) on detecting recurrence in these circumstances. Eighty-four patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb under ETS were included. Correlation with clinicopathological features and recurrence, detectability of FDG PET/CT and cut-off value of serum Tg for recurrence in PTC patients with these circumstance were assessed. In addition, detectability of F-18 FDG PET/CT under ETS and suppression were compared. In Cox regression analysis, only serum Tg level was significantly associated with recurrence (P<0.001, HR  = 1.13; 95 % CI, 1.061–1.208). The cut-off level of Tg was 21.5 ng/mL (AUC, 0.919; P < 0.001) for discriminating the recurrence in the patients with positive PET/CT finding. The sensitivity, specificity, PPV, NPV, and accuracy of F-18 FDG PET/CT for detecting recurrence were 64 %, 94 %, 86 %, 81 %, and 83 %. In the analysis of F-18 FDG PET/CT under ETS, the sensitivity, specificity, PPV, NPV and accuracy was 64 %, 94 %, 88 %, 81 % and 83 %. Those under TSH suppression were 67 %, 92 %, 80 %, 85 % and 83 %. F-18 FDG PET/CT, although less sensitive, showed high specificity, PPV, NPV, and accuracy and therefore can be useful for the patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb. In addition, FDG PET/CT under ETS does not seem to have an additive role in detecting recurrence in these patients.

Preliminary discussion on the value of 18F-FDG PET/CT in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas

International Nuclear Information System (INIS)

Dan, Shao; Qiang, Gao; Shu-Xia, Wang; Chang-Hong, Liang

2015-01-01

Highlights: • We discussed the value of PET/CT in the diagnosis and early staging of non-MF/SS CML. • We calculated the sensitivity of CT and PET/CT in the diagnosis of primary skin lesions. • We calculated the value of CT and PET/CT in the diagnosis of LNs and other organs. - Abstract: Objective: To discuss the value of 18 F-fluorodeoxyglucose-positron emission tomography ( 18 F-PET/CT) scans in the diagnosis and early staging of non-mycosis fungoides/Sézary's syndrome cutaneous malignant lymphomas (non-MF/SS CML). Materials and methods: A total of 18 cases with non-MF/SS CML, confirmed by pathology or on clinical grounds, were analyzed in this study. The sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions, as well as the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of lymph nodes (LNs) and other organs (except skin and LNs) were calculated. Results: The diagnostic sensitivity of CT and PET/CT scans in the diagnosis of primary skin lesions was 82.4% (14/17) and 100% (17/17), respectively. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CT and PET/CT scans in the diagnosis of LN lesions were 55.6% (5/9), 88.9% (8/9), 72.2% (13/18), 83.3% (5/6), 66.7% (8/12), and 88.9% (8/9), 100% (9/9), 94.4% (17/18), 100% (8/8), 90.0% (9/10), respectively. The diagnostic value of the CT and PET/CT scans in the diagnosis of involvement of other organs, were 40.4% (2/5), 100% (13/13), 83.3 (15/18), 100% (2/2), 81.3% (13/16) and 80.6% (4/5), 100% (13/13), 94.4% (17/18), 100% (3/3), 92.9% (13/14), respectively. Conclusions: 18 F-FDG PET/CT has high value in the diagnosis and early staging of non-MF/SS CMLs

Present and future of PET and PET/CT in gynaecologic malignancies

Energy Technology Data Exchange (ETDEWEB)

Musto, Alessandra [Department of Nuclear Medicine, PET Center, Policlinico Sant' Orsola Malpighi, Bologna University, Bologna (Italy); Rampin, Lucia [Department of Nuclear Medicine, PET Center, Radiology, Medical Physics, Santa Maria della Misericordia Hospital, viale tre martiri 140, 45100 Rovigo (Italy); Nanni, Cristina [Department of Nuclear Medicine, PET Center, Policlinico Sant' Orsola Malpighi, Bologna University, Bologna (Italy); Marzola, Maria Cristina [Department of Nuclear Medicine, PET Center, Radiology, Medical Physics, Santa Maria della Misericordia Hospital, viale tre martiri 140, 45100 Rovigo (Italy); Fanti, Stefano [Department of Nuclear Medicine, PET Center, Policlinico Sant' Orsola Malpighi, Bologna University, Bologna (Italy); Rubello, Domenico, E-mail: domenico.rubello@libero.it [Department of Nuclear Medicine, PET Center, Radiology, Medical Physics, Santa Maria della Misericordia Hospital, viale tre martiri 140, 45100 Rovigo (Italy)

2011-04-15

Objectives: To review the published data in literature on patients affected by gynaecological malignancies to establish the role of {sup 18}F-FDG positron emission tomography (PET) and PET/CT in comparison to conventional imaging (CI). Materials and methods: All papers specifically addressed to the role of {sup 18}F-FDG PET and PET/CT in gynaecological malignancies published on PubMed/Medline, in abstracts from the principal international congresses, in the guidelines from national Societies that had appeared in literature until November 2009 were considered for the purpose of the present study. Results and conclusions: The use of {sup 18}F-FDG PET, and even more of {sup 18}F-FDG PET/CT, is increasing in the follow up of patients with gynaecologic malignancies and suspected recurrent disease: there is evidence in the literature that {sup 18}F-FDG PET/CT has a higher sensitivity than CI in depicting occult metastatic spread. An interesting issue is represented by patients with ovarian cancer with an increase of the specific biomarker, CA-125, and negative/inconclusive findings at CI. The use of {sup 18}F-FDG PET in differential diagnosis and staging is more controversial, but there is some evidence that a baseline PET examination performed before commencing therapy, for staging purpose, is also useful to evaluate the response to chemoradiation treatment. In several papers it has been suggested a relevant role of {sup 18}F-FDG PET/CT in evaluating the entity of response to treatment and therefore to plan the subsequent therapeutic strategy.

Quantitative and Visual Assessments toward Potential Sub-mSv or Ultrafast FDG PET Using High-Sensitivity TOF PET in PET/MRI.

Science.gov (United States)

Behr, Spencer C; Bahroos, Emma; Hawkins, Randall A; Nardo, Lorenzo; Ravanfar, Vahid; Capbarat, Emily V; Seo, Youngho

2018-06-01

Newer high-performance time-of-flight (TOF) positron emission tomography (PET) systems have the capability to preserve diagnostic image quality with low count density, while maintaining a high raw photon detection sensitivity that would allow for a reduction in injected dose or rapid data acquisition. To assess this, we performed quantitative and visual assessments of the PET images acquired using a highly sensitive (23.3 cps/kBq) large field of view (25-cm axial) silicon photomultiplier (SiPM)-based TOF PET (400-ps timing resolution) integrated with 3 T-MRI in comparison to PET images acquired on non-TOF PET/x-ray computed tomography (CT) systems. Whole-body 2-deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG) PET/CT was acquired for 15 patients followed by whole body PET/magnetic resonance imaging (MRI) with an average injected dose of 325 ± 84 MBq. The PET list mode data from PET/MRI were reconstructed using full datasets (4 min/bed) and reduced datasets (2, 1, 0.5, and 0.25 min/bed). Qualitative assessment between PET/CT and PET/MR images were made. A Likert-type scale between 1 and 5, 1 for non-diagnostic, 3 equivalent to PET/CT, and 5 superior quality, was used. Maximum and mean standardized uptake values (SUV max and SUV mean ) of normal tissues and lesions detected were measured and compared. Mean visual assessment scores were 3.54 ± 0.32, 3.62 ± 0.38, and 3.69 ± 0.35 for the brain and 3.05 ± 0.49, 3.71 ± 0.45, and 4.14 ± 0.44 for the whole-body maximum intensity projections (MIPs) for 1, 2, and 4 min/bed PET/MR images, respectively. The SUV mean values for normal tissues were lower and statistically significant for images acquired at 4, 2, 1, 0.5, and 0.25 min/bed on the PET/MR, with values of - 18 ± 28 % (p PET/MR datasets. High-sensitivity TOF PET showed comparable but still better visual image quality even at a much reduced activity in comparison to lower-sensitivity non-TOF PET. Our data translates to a seven times

Phantom study on three-dimensional target volume delineation by PET/CT-based auto-contouring

International Nuclear Information System (INIS)

Zhang, Tiejiao; Sakaguchi, Yuichi; Mitsumoto, Katsuhiko; Mitsumoto, Tatsuya; Sasaki, Masayuki; Tachiya, Yosuke; Ohya, Nobuyoshi

2010-01-01

The aim of this study was to determine an appropriate threshold value for delineation of the target volume in positron emission tomography (PET)/CT and to investigate whether we could delineate a target volume by phantom studies. A phantom consisted of six spheres (φ10-37 mm) filled with 18 F solution. Data acquisition was performed PET/CT in non-motion and motion status with high 18 F solution and in non-motion status with low 18 F solution. In non-motion phantom experiments, we determined two types of threshold value, an absolute SUV (T SUV ) and a percentage of the maximum SUV (T % ). Delineation using threshold values was applied for all spheres and for selected large spheres (a diameter of 22 mm or larger). In motion phantom experiments, data acquisition was performed in a static mode (sPET) and a gated mode (gPET). CT scanning was performed with helical CT (HCT) and 4-dimentional CT (4DCT). The appropriate threshold values were aT % =27% and aT SUV =2.4 for all spheres, and sT % =30% and sT SUV =4.3 for selected spheres. For all spheres in sPET/HCT in motion, the delineated volumes were 84%-129% by the aT % and 34%-127% by the aT SUV . In gPET/4DCT in motion, the delineated volumes were 94-103% by the aT % and 51-131% by the aT SUV . For low radioactivity spheres, the delineated volumes were all underestimated. A threshold value of T % =27% was proposed for auto-contouring of lung tumors. Our results also suggested that the respiratory gated data acquisition should be performed in both PET and CT for target volume delineation. (author)

Imaging with 124I in differentiated thyroid carcinoma: is PET/MRI superior to PET/CT?

International Nuclear Information System (INIS)

Binse, I.; Poeppel, T.D.; Ruhlmann, M.; Gomez, B.; Bockisch, A.; Rosenbaum-Krumme, S.J.; Umutlu, L.

2016-01-01

The aim of this study was to compare integrated PET/CT and PET/MRI for their usefulness in detecting and categorizing cervical iodine-positive lesions in patients with differentiated thyroid cancer using 124 I as tracer. The study group comprised 65 patients at high risk of iodine-positive metastasis who underwent PET/CT (low-dose CT scan, PET acquisition time 2 min; PET/CT 2 ) followed by PET/MRI of the neck 24 h after 124 I administration. PET images from both modalities were analysed for the numbers of tracer-positive lesions. Two different acquisition times were used for the comparisons, one matching the PET/CT 2 acquisition time (2 min, PET/MRI 2 ) and the other covering the whole MRI scan time (30 min, PET/MRI 30 ). Iodine-positive lesions were categorized as metastasis, thyroid remnant or inconclusive according to their location on the PET/CT images. Morphological information provided by MRI was considered for evaluation of lesions on PET/MRI and for volume information. PET/MRI 2 detected significantly more iodine-positive metastases and thyroid remnants than PET/CT 2 (72 vs. 60, p = 0.002, and 100 vs. 80, p = 0.001, respectively), but the numbers of patients with at least one tumour lesion identified were not significantly different (21/65 vs. 17/65 patients). PET/MRI 30 tended to detect more PET-positive metastases than PET/MRI 2 (88 vs. 72), but the difference was not significant (p = 0.07). Of 21 lesions classified as inconclusive on PET/CT, 5 were assigned to metastasis or thyroid remnant when evaluated by PET/MRI. Volume information was available in 34 % of iodine-positive metastases and 2 % of thyroid remnants on PET/MRI. PET/MRI of the neck was found to be superior to PET/CT in detecting iodine-positive lesions. This was attributed to the higher sensitivity of the PET component, Although helpful in some cases, we found no substantial advantage of PET/MRI over PET/CT in categorizing iodine-positive lesions as either metastasis or thyroid remnant

18F-FDG PET/CT显像诊断妇科肿瘤复发、转移的价值%Value of18F-FDG PET/CT in diagnosing suspected recurrence and metastasis in gynecological malignancies

Institute of Scientific and Technical Information of China (English)

张敬勉; 赵新明; 王建方; 王颖晨; 张召奇; 李德志; 戴春暖; 孙莉; 江志华

2009-01-01

Objective Recurrence and metastasis are significant prognostic factors in patients with gynecological malignancies. The purpose of the study was to evaluate the value of 18F-fluorodeoxyglucose (FDG) PET/CT in diagnosing suspected recurrence and metastasis in gynecological malignancies, and to investigate the influence of PET/CT on clinical restaging and treatment decision. Methods Forty-seven patients with gynecological malignancies clinically suspected of recurrence or metastasis underwent 18 F-FDG PET/CT imaging. The images of 18F-FDG PET/CT, PET and CT were compared respectively. X2-test with SPSS 12.0 was used for data analysis. Results One hundred and forty-nine malignant lesions and 9 benign lesions were found in 47 patients. The sensitivity, specificity, accuracy, positive predictive value and nega-tive predictive value of 18 F-FDG PET/CT in detecting recurrence and metastasis of gynecological malignan-cies were 95.97% ( 143/149), 6/9, 94.30% ( 149/158), 97.95% (143/146) and 50.00% ( 6/12), respectively. The difference was significant between ,18 F-FDG PET/CT image and CT alone in sensitivity, ac-curacy and negative predictive value (X2 = 18.198,18.890, 6.825, all P 0.05), but 18F-FDG PET/CT had a clear advantage in determining the location of the lesions [33.54% (53/158)]. PET/CT changed the TN M staging in 44.68% ( 21/47 ) and 31.91% (15/47) patients, respectively, comparing with CT or PET alone. Furthermore, 19.15% ( 9/47 ) had change in their clinical staging and treatment decision based on the results of PET/CT. Conclu-sion 18F-FDG PET/CT is valuable in the detection, restaging and management decision in recurrent and metastatic gynecological malignancies.%目的 探讨18F-脱氧葡萄糖(FDG)PET/CT显像诊断妇科肿瘤复发、转移的价值,并评价其对临床再分期及治疗决策的影响.方法 对47例临床可疑复发、转移的妇科肿瘤患者行18F-FDGPET/CT显像,对PET、CT及PET/CT图像进行对比分析.采用SPSS 12.0�

The Role of 18F-FDG PET/CT Integrated Imaging in Distinguishing Malignant from Benign Pleural Effusion

Science.gov (United States)

Sun, Yajuan; Yu, Hongjuan; Ma, Jingquan

2016-01-01

Objective The aim of our study was to evaluate the role of 18F-FDG PET/CT integrated imaging in differentiating malignant from benign pleural effusion. Methods A total of 176 patients with pleural effusion who underwent 18F-FDG PET/CT examination to differentiate malignancy from benignancy were retrospectively researched. The images of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were visually analyzed. The suspected malignant effusion was characterized by the presence of nodular or irregular pleural thickening on CT imaging. Whereas on PET imaging, pleural 18F-FDG uptake higher than mediastinal activity was interpreted as malignant effusion. Images of 18F-FDG PET/CT integrated imaging were interpreted by combining the morphologic feature of pleura on CT imaging with the degree and form of pleural 18F-FDG uptake on PET imaging. Results One hundred and eight patients had malignant effusion, including 86 with pleural metastasis and 22 with pleural mesothelioma, whereas 68 patients had benign effusion. The sensitivities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging in detecting malignant effusion were 75.0%, 91.7% and 93.5%, respectively, which were 69.8%, 91.9% and 93.0% in distinguishing metastatic effusion. The sensitivity of 18F-FDG PET/CT integrated imaging in detecting malignant effusion was higher than that of CT imaging (p = 0.000). For metastatic effusion, 18F-FDG PET imaging had higher sensitivity (p = 0.000) and better diagnostic consistency with 18F-FDG PET/CT integrated imaging compared with CT imaging (Kappa = 0.917 and Kappa = 0.295, respectively). The specificities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were 94.1%, 63.2% and 92.6% in detecting benign effusion. The specificities of CT imaging and 18F-FDG PET/CT integrated imaging were higher than that of 18F-FDG PET imaging (p = 0.000 and p = 0.000, respectively), and CT imaging had better diagnostic consistency with

The Role of 18F-FDG PET/CT Integrated Imaging in Distinguishing Malignant from Benign Pleural Effusion.

Science.gov (United States)

Sun, Yajuan; Yu, Hongjuan; Ma, Jingquan; Lu, Peiou

2016-01-01

The aim of our study was to evaluate the role of 18F-FDG PET/CT integrated imaging in differentiating malignant from benign pleural effusion. A total of 176 patients with pleural effusion who underwent 18F-FDG PET/CT examination to differentiate malignancy from benignancy were retrospectively researched. The images of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were visually analyzed. The suspected malignant effusion was characterized by the presence of nodular or irregular pleural thickening on CT imaging. Whereas on PET imaging, pleural 18F-FDG uptake higher than mediastinal activity was interpreted as malignant effusion. Images of 18F-FDG PET/CT integrated imaging were interpreted by combining the morphologic feature of pleura on CT imaging with the degree and form of pleural 18F-FDG uptake on PET imaging. One hundred and eight patients had malignant effusion, including 86 with pleural metastasis and 22 with pleural mesothelioma, whereas 68 patients had benign effusion. The sensitivities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging in detecting malignant effusion were 75.0%, 91.7% and 93.5%, respectively, which were 69.8%, 91.9% and 93.0% in distinguishing metastatic effusion. The sensitivity of 18F-FDG PET/CT integrated imaging in detecting malignant effusion was higher than that of CT imaging (p = 0.000). For metastatic effusion, 18F-FDG PET imaging had higher sensitivity (p = 0.000) and better diagnostic consistency with 18F-FDG PET/CT integrated imaging compared with CT imaging (Kappa = 0.917 and Kappa = 0.295, respectively). The specificities of CT imaging, 18F-FDG PET imaging and 18F-FDG PET/CT integrated imaging were 94.1%, 63.2% and 92.6% in detecting benign effusion. The specificities of CT imaging and 18F-FDG PET/CT integrated imaging were higher than that of 18F-FDG PET imaging (p = 0.000 and p = 0.000, respectively), and CT imaging had better diagnostic consistency with 18F-FDG PET/CT integrated

Magnetic Resonance-based Motion Correction for Quantitative PET in Simultaneous PET-MR Imaging.

Science.gov (United States)

Rakvongthai, Yothin; El Fakhri, Georges

2017-07-01

Motion degrades image quality and quantitation of PET images, and is an obstacle to quantitative PET imaging. Simultaneous PET-MR offers a tool that can be used for correcting the motion in PET images by using anatomic information from MR imaging acquired concurrently. Motion correction can be performed by transforming a set of reconstructed PET images into the same frame or by incorporating the transformation into the system model and reconstructing the motion-corrected image. Several phantom and patient studies have validated that MR-based motion correction strategies have great promise for quantitative PET imaging in simultaneous PET-MR. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical utility of simultaneous whole-body 18F-FDG PET/MRI as a single-step imaging modality in the staging of primary nasopharyngeal carcinoma.

Science.gov (United States)

Chan, Sheng-Chieh; Yeh, Chih-Hua; Yen, Tzu-Chen; Ng, Shu-Hang; Chang, Joseph Tung-Chieh; Lin, Chien-Yu; Yen-Ming, Tsang; Fan, Kang-Hsing; Huang, Bing-Shen; Hsu, Cheng-Lung; Chang, Kai-Ping; Wang, Hung-Ming; Liao, Chun-Ta

2018-03-03

Both head and neck magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) play a crucial role in the staging of primary nasopharyngeal carcinoma (NPC). In this study, we sought to prospectively investigate the clinical utility of simultaneous whole-body 18F-FDG PET/MRI for primary staging of NPC patients. We examined 113 patients with histologically confirmed NPC who underwent pretreatment, simultaneous whole-body PET/MRI and PET/CT for primary tumor staging. The images obtained with the different imaging modalities were interpreted independently and compared with each other. PET/MRI increased the accuracy of head and neck MRI for assessment of primary tumor extent in four patients via addition of FDG uptake information to increase the conspicuity of morphologically subtle lesions. PET/MR images were more discernible than PET/CT images for mapping tumor extension, especially intracranial invasion. Regarding the N staging assessment, the sensitivity of PET/MRI (99.5%) was higher than that of head and neck MRI (94.2%) and PET/CT (90.9%). PET/MRI was particularly useful for distinguishing retropharyngeal nodal metastasis from adjacent nasopharyngeal tumors. For distant metastasis evaluation, PET/MRI exhibited a similar sensitivity (90% vs. 86.7% vs. 83.3%), but higher positive predictive value (93.1% vs. 78.8% vs. 83.3%) than whole-body MRI and PET/CT, respectively. For tumor staging of NPC, simultaneous whole-body PET/MRI was more accurate than head and neck MRI and PET/CT, and may serve as a single-step staging modality.

Sensory analysis of pet foods.

Science.gov (United States)

Koppel, Kadri

2014-08-01

Pet food palatability depends first and foremost on the pet and is related to the pet food sensory properties such as aroma, texture and flavor. Sensory analysis of pet foods may be conducted by humans via descriptive or hedonic analysis, pets via acceptance or preference tests, and through a number of instrumental analysis methods. Sensory analysis of pet foods provides additional information on reasons behind palatable and unpalatable foods as pets lack linguistic capabilities. Furthermore, sensory analysis may be combined with other types of information such as personality and environment factors to increase understanding of acceptable pet foods. Most pet food flavor research is proprietary and, thus, there are a limited number of publications available. Funding opportunities for pet food studies would increase research and publications and this would help raise public awareness of pet food related issues. This mini-review addresses current pet food sensory analysis literature and discusses future challenges and possibilities. © 2014 Society of Chemical Industry.

The Pet Factor - Companion Animals as a Conduit for Getting to Know People, Friendship Formation and Social Support

Science.gov (United States)

Wood, Lisa; Martin, Karen; Christian, Hayley; Nathan, Andrea; Lauritsen, Claire; Houghton, Steve; Kawachi, Ichiro; McCune, Sandra

2015-01-01

Background While companion animals have been previously identified as a direct source of companionship and support to their owners, their role as a catalyst for friendship formation or social support networks among humans has received little attention. This study investigated the indirect role of pets as facilitators for three dimensions of social relatedness; getting to know people, friendship formation and social support networks. Methods A telephone survey of randomly selected residents in four cities, one in Australia (Perth; n = 704) and three in the U.S. (San Diego, n = 690; Portland, n = 634; Nashville, n = 664) was conducted. All participants were asked about getting to know people within their neighborhood. Pet owners were asked additional questions about the type/s of pet/s they owned, whether they had formed friendships as a result of their pet, and if they had received any of four different types of social support from the people they met through their pet. Results Pet owners were significantly more likely to get to know people in their neighborhood than non-pet owners (OR 1.61; 95%CI: 1.30, 1.99). When analyzed by site, this relationship was significant for Perth, San Diego and Nashville. Among pet owners, dog owners in the three U.S. cities (but not Perth) were significantly more likely than owners of other types of pets to regard people whom they met through their pet as a friend (OR 2.59; 95%CI: 1.94, 3.46). Around 40% of pet owners reported receiving one or more types of social support (i.e. emotional, informational, appraisal, instrumental) via people they met through their pet. Conclusion This research suggests companion animals can be a catalyst for several dimensions of human social relationships in neighborhood settings, ranging from incidental social interaction and getting to know people, through to formation of new friendships. For many pet owners, their pets also facilitated relationships from which they derived tangible forms of social

The pet factor--companion animals as a conduit for getting to know people, friendship formation and social support.

Science.gov (United States)

Wood, Lisa; Martin, Karen; Christian, Hayley; Nathan, Andrea; Lauritsen, Claire; Houghton, Steve; Kawachi, Ichiro; McCune, Sandra

2015-01-01

While companion animals have been previously identified as a direct source of companionship and support to their owners, their role as a catalyst for friendship formation or social support networks among humans has received little attention. This study investigated the indirect role of pets as facilitators for three dimensions of social relatedness; getting to know people, friendship formation and social support networks. A telephone survey of randomly selected residents in four cities, one in Australia (Perth; n = 704) and three in the U.S. (San Diego, n = 690; Portland, n = 634; Nashville, n = 664) was conducted. All participants were asked about getting to know people within their neighborhood. Pet owners were asked additional questions about the type/s of pet/s they owned, whether they had formed friendships as a result of their pet, and if they had received any of four different types of social support from the people they met through their pet. Pet owners were significantly more likely to get to know people in their neighborhood than non-pet owners (OR 1.61; 95%CI: 1.30, 1.99). When analyzed by site, this relationship was significant for Perth, San Diego and Nashville. Among pet owners, dog owners in the three U.S. cities (but not Perth) were significantly more likely than owners of other types of pets to regard people whom they met through their pet as a friend (OR 2.59; 95%CI: 1.94, 3.46). Around 40% of pet owners reported receiving one or more types of social support (i.e. emotional, informational, appraisal, instrumental) via people they met through their pet. This research suggests companion animals can be a catalyst for several dimensions of human social relationships in neighborhood settings, ranging from incidental social interaction and getting to know people, through to formation of new friendships. For many pet owners, their pets also facilitated relationships from which they derived tangible forms of social support, both of a practical and

The pet factor--companion animals as a conduit for getting to know people, friendship formation and social support.

Directory of Open Access Journals (Sweden)

Lisa Wood

Full Text Available While companion animals have been previously identified as a direct source of companionship and support to their owners, their role as a catalyst for friendship formation or social support networks among humans has received little attention. This study investigated the indirect role of pets as facilitators for three dimensions of social relatedness; getting to know people, friendship formation and social support networks.A telephone survey of randomly selected residents in four cities, one in Australia (Perth; n = 704 and three in the U.S. (San Diego, n = 690; Portland, n = 634; Nashville, n = 664 was conducted. All participants were asked about getting to know people within their neighborhood. Pet owners were asked additional questions about the type/s of pet/s they owned, whether they had formed friendships as a result of their pet, and if they had received any of four different types of social support from the people they met through their pet.Pet owners were significantly more likely to get to know people in their neighborhood than non-pet owners (OR 1.61; 95%CI: 1.30, 1.99. When analyzed by site, this relationship was significant for Perth, San Diego and Nashville. Among pet owners, dog owners in the three U.S. cities (but not Perth were significantly more likely than owners of other types of pets to regard people whom they met through their pet as a friend (OR 2.59; 95%CI: 1.94, 3.46. Around 40% of pet owners reported receiving one or more types of social support (i.e. emotional, informational, appraisal, instrumental via people they met through their pet.This research suggests companion animals can be a catalyst for several dimensions of human social relationships in neighborhood settings, ranging from incidental social interaction and getting to know people, through to formation of new friendships. For many pet owners, their pets also facilitated relationships from which they derived tangible forms of social support, both of a practical

The application of PET and PET-CT in cervical cancer

International Nuclear Information System (INIS)

Huang Jianmin; Pan Liping; Li Dongxue

2007-01-01

Cervical cancer is the common malignancies in woman, 18 F-fluorodeoxyglucose ( 18 F-FDG) PET is a well-established method for detecting, staging, cancer recurrence, therapeutic response and prognosis of cervical cancer. PET-CT can accurately locate the anatomical sites of tracer uptake and improve the diagnostic accuraccy of PET. (authors)

The petit rat (pet/pet), a new semilethal mutant dwarf rat with thymic and testicular anomalies.

Science.gov (United States)

Chiba, Junko; Suzuki, Katsushi; Suzuki, Hiroetsu

2008-12-01

The petit rat (pet/pet) is a recently discovered semilethal mutant dwarf. The neonatal pet/pet rats had a low body weight and small thymus and testis. During the first 3 d after birth, 50% of the male and 80% of the female pet/pet pups were lost or found dead. Surviving pet/pet rats showed marked retardation of postnatal growth, and their body weights were 41% (female rats) and 32% (male rats) of those of normal rats at the adult stage. The pet/pet rats exhibited proportional dwarfism, and their longitudinal bones were shorter than those of controls without skeletal malformations. Most organs of male pet/pet rats, especially the thymus, testis, adipose tissue surrounding the kidney, and accessory sex organs, weighed markedly less at 140 d of age than did those of their normal counterparts. The thymus of pet/pet rats was small with abnormal thymic follicles. Testes from pet/pet rats exhibited 2 patterns of abnormal histology. Spermatogenesis was present in testes that were only slightly anomalous, but the seminiferous tubules were reduced in diameter. In severely affected testes, most of the seminiferous tubules showed degeneration, and interstitial tissue was increased. Plasma growth hormone concentrations did not differ between pet/pet and normal male rats. The dwarf phenotype of pet/pet rats was inherited as an autosomal recessive trait. These results indicate that the pet/pet rat has a semilethal growth-hormone-independent dwarf phenotype that is accompanied by thymic and testicular anomalies and low birth weight.

Value of PET and PET-CT for monitoring tumor therapy

International Nuclear Information System (INIS)

Chen Xiang; Zhao Jinhua

2007-01-01

18 F-fluorodeoxyglucose ( 18 F-FDG) PET or PET-CT is an accurate test for differentiating residual viable tumor tissue from therapy-induced changes in tumor. Furthermore, quantitative assessment of therapy-induced changes in tumor 18 F-FDG uptake may allow the prediction of tumor response. Treatment may be adjusted according to tumor response. So it is increasingly used to monitor tumor response in patients undergoing chemotherapy and chemoradiotherapy. Here we focused on practical aspects of 18 F-FDG PET or PET-CT for treatment monitoring and on the existing advantages and challenges. (authors)

{sup 18}F-Fluoride PET/CT for detection of sacroiliitis in ankylosing spondylitis

Energy Technology Data Exchange (ETDEWEB)

Strobel, Klaus [University Hospital, Department of Medical Radiology, Division of Nuclear Medicine, Zurich (Switzerland); Cantonal Hospital Lucerne, Nuclear Medicine, Lucerne (Switzerland); Fischer, Dorothee R.; Stumpe, Katrin D.M.; Schulthess, Gustav K. von [University Hospital, Department of Medical Radiology, Division of Nuclear Medicine, Zurich (Switzerland); Tamborrini, Giorgio; Kyburz, Diego; Michel, Beat A.; Ciurea, Adrian [University Hospital Zurich, Department of Rheumatology, Zurich (Switzerland); Hesselmann, Rolf G.X.; Johayem, A. [University Hospital Zurich, Radiopharmacy, Zurich (Switzerland)

2010-09-15

The aim of this study was to evaluate the performance of {sup 18}F-fluoride-PET/CT (PET/CT) for the diagnosis of sacroiliac joint (SIJ) arthritis in patients with active ankylosing spondylitis (AS). Included in the study were 15 patients with AS according to the modified New York criteria (AS group) and with active disease and 13 patients with mechanical low back pain (MLBP; control group) who were investigated with whole-body {sup 18}F-fluoride PET/CT. The ratio of the uptake in the SIJ and that in the sacrum (SIJ/S) was calculated for every joint. The mean SIJ/S ratio of 30 quantified joints in the AS group was 1.66 (range 1.10-3.07) with PET/CT, and the mean SIJ/S ratio of 26 quantified joints in the MLBP group was 1.12 (range 0.71-1.52). The area under the receiver operating characteristic curve for SIJ arthritis was 0.84. With plain radiography as a the gold standard and taking an SIJ/S ratio of >1.3 as the threshold, the sensitivity, specificity and accuracy on a per patient basis were 80%, 77% and 79%, respectively. On a per SIJ basis, the greatest sensitivity (94%) was found in grade 3 sacroiliitis (n = 16). Our results suggest that quantitative {sup 18}F-fluoride PET/CT may play a role in the diagnosis of sacroiliitis in active AS and is an alternative to conventional bone scintigraphy in times of molybdenum shortage. (orig.)

Restaging of patients with lymphoma. Comparison of low dose CT (20 mAs) with contrast enhanced diagnostic CT in combined [18F]-FDG PET/CT

International Nuclear Information System (INIS)

Fougere, C. la; Pfluger, T.; Schneider, V.; Hacker, M.; Broeckel, N.; Bartenstein, P.; Tiling, R.; Morhard, D.; Hundt, W.; Becker, C.

2008-01-01

Aim: assessment of the clinical benefit of i.v. contrast enhanced diagnostic CT (CE-CT) compared to low dose CT with 20 mAs (LD-CT) without contrast medium in combined [ 18 F]-FDG PET/CT examinations in restaging of patients with lymphoma. Patients, methods: 45 patients with non-Hodgkin lymphoma (n = 35) and Hodgkin's disease (n = 10) were included into this study. PET, LD-CT and CE-CT were analyzed separately as well as side-by-side. Lymphoma involvement was evaluated separately for seven regions. Indeterminate diagnoses were accepted whenever there was a discrepancy between PET and CT findings. Results for combined reading were calculated by rating indeterminate diagnoses according the suggestions of either CT or PET. Each patient had a clinical follow-up evaluation for > 6 months. Results: region-based evaluation suggested a sensitivity/specificity of 66/93% for LD-CT, 87%/91% for CE-CT, 95%/96% for PET, 94%/99% for PET/LD-CT and 96%/99% for PET/CE-CT. The data for PET/CT were obtained by rating indeterminate results according to the suggestions of PET, which turned out to be superior to CT. Lymphoma staging was changed in two patients using PET/CE-CT as compared to PET/LD-CT. Conclusion: overall, there was no significant difference between PET/LD-CT and PET/CE-CT. However, PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This was due to the improved image quality of CE-CT and might lead to a more accurate investigation of lymphoma. (orig.)

77 FR 2972 - Thunder Bay Power Company, Thunder Bay Power, LLC, et al.

Science.gov (United States)

2012-01-20

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Thunder Bay Power Company, Thunder Bay Power, LLC, et al.; Notice of Application for Transfer of Licenses, and Soliciting Comments and Motions To Intervene Thunder Bay Power Company Project No. 2404-095 Thunder Bay Power, LLC Midwest Hydro, Inc...

Processing and characterization of extruded PET and its r-PET and ...

Indian Academy of Sciences (India)

of r-PET and r-PET+ MWCNT fillers was obtained by the precipitation method using TFA as a solvent and acetone ... crystallinity in r-PET and decrease in chain entanglements. ..... insufficient to supply the complete information of the surface.

PET and PET/CT in tumour of undetermined origin

International Nuclear Information System (INIS)

Garcia O, J.R.

2007-01-01

In this presentation the following conclusions were obtained regarding the use of PET and PET/CT in patient with cancer of unknown primary: 1. Detection of the primary one in 1/3 at 1/2 of patient. 2. It detects metastases in other places in 50%. 3. It changes the initial therapy planned in 1/3 at 1/2 of patient. 4. Useful in initial phases of protocol study to limit the other procedures. After standard evaluation. Before advanced protocol. 5. PET/CT study increases the % of primary detection, although in a non significant way vs. PET. 6. They are required more studies to value their utility to a more objective manner. (Author)

Clinical applications of PET/CT

International Nuclear Information System (INIS)

Le Ngoc Ha

2011-01-01

The purpose of this article is to review the evolution of PET, PET/CT focusing on the technical aspects, PET radiopharmaceutical developments and current clinical applications as well. The newest technologic advances have been reviewed, including improved crystal design, acquisition modes, reconstruction algorithms, etc. These advancements will continue to improve contrast, decrease noise, and increase resolution. Combined PET/CT system provides faster attenuation correction and useful anatomic correlation to PET functional information. A number of new radiopharmaceuticals used for PET imaging have been developed, however, FDG have been considered as the principal PET radiotracer. The current clinical applications of PET and PET/CT are widespread and include oncology, cardiology and neurology. (author)

Diagnosis and dosimetry in differentiated thyroid carcinoma using 124I PET: comparison of PET/MRI vs PET/CT of the neck

International Nuclear Information System (INIS)

Nagarajah, James; Jentzen, Walter; Hartung, Verena; Rosenbaum-Krumme, Sandra; Bockisch, Andreas; Stahl, Alexander; Mikat, Christian; Heusner, Till Alexander; Antoch, Gerald

2011-01-01

This study compares intrinsically coregistered 124 I positron emission tomography (PET) and CT (PET/CT) and software coregistered 124 I PET and MRI (PET/MRI) images for the diagnosis and dosimetry of thyroid remnant tissues and lymph node metastases in patients with differentiated thyroid carcinoma (DTC). After thyroidectomy, 33 high-risk DTC patients (stage III or higher) received 124 I PET/CT dosimetry prior to radioiodine therapy to estimate the absorbed dose to lesions and subsequently underwent a contrast-enhanced MRI examination of the neck. Images were evaluated by two experienced nuclear medicine physicians and two radiologists to identify the lesions and to categorize their presumable provenience, i.e. thyroid remnant tissue (TT), lymph node metastasis (LN) and inconclusive tissue. The categorization and dosimetry of lesions was initially performed with PET images alone (PET only). Subsequently lesions were reassessed including the CT and MRI data. The analyses were performed on a patient and on a lesion basis. Patient-based analyses showed that 26 of 33 (79%) patients had at least one lesion categorized as TT on PET only. Of these patients, 11 (42%) and 16 (62%) had a morphological correlate on CT and MRI, respectively, in at least one TT PET lesion. Twelve patients (36%) had at least one lesion classified as LN on PET only. Nine (75%) of these patients had a morphological correlate on both CT and MRI in at least one LN PET lesion. Ten patients (30%) showed at least one lesion on PET only classified as inconclusive. The classification was changed to a clear classification in two patients (two LN) by CT and in four (two TT, two LN) patients by MRI. Lesion-based analyses (n = 105 PET positive lesions) resulted in categorization as TT in 61 cases (58%), 16 (26%) of which had a morphological correlate on CT and 33 (54%) on MRI. A total of 29 lesions (27%) were classified as LN on PET, 18 (62%) of which had a morphological correlate on CT and 24 (83%) on MRI

Clinical Application of F-18 FDG PET (PET/CT) in Colo-rectal and Anal Cancer

International Nuclear Information System (INIS)

Kim, Byung Il

2008-01-01

In the management of colo-retal and anal cancer, accurate staging, treatment evaluation, early detection of recurrence are main clinical problems. F-18 FDG PET (PET/CT) has been reported as useful in the management of colo-rectal and anal cancer because that PET has high diagnostic performance comparing to conventional studies. In case of liver metastases, for confirmation of no extrahepatic metastases, in case of high risk of metastasis, for avoiding unnecessary operation, PET (PET/CT) is expected more useful. In anal cancer, PET is expected useful in lymph node staging. For the early prediction of chemotherapy or radiation therapy effect PET has been reported as useful, also. In early detection of recurrence by PET, cost-benefit advantages has been suggested, also. PET/CT is expected to have higher diagnostic performance than PET alone

Clinical Application of F-18 FDG PET (PET/CT) in Malignancy of Unknown Origin

International Nuclear Information System (INIS)

Kim, Byung Il

2008-01-01

Diagnosis of primary origin site in the management of malignancy of unknown origin (MUO) is the most important issue. According to the histopathologic subtype of primary lesion, specialized treatment can be given and survival gain is expected. F-18 FDG PET (PET/CT) has been estimated as useful in detection of primary lesion with high sensitivity and moderate specificity. F-18 FDG PET (PET/CT) study before conventional studies is also recommended because it has high diagnostic performance compared to conventional studies. Although there has few data, F-18 FDG PET (PET/CT) is expected to be useful in diagnosis of recurrence, restaging, evaluation of treatment effect, considering that PET (PET/CT) has been reported as useful in other malignancies

Basic study of entire whole-body PET scanners based on the OpenPET geometry

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Eiji, E-mail: rush@nirs.go.j [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Yamaya, Taiga; Nishikido, Fumihiko; Inadama, Naoko; Murayama, Hideo [National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan)

2010-09-21

A conventional PET scanner has a 15-25 cm axial field-of-view (FOV) and images a whole body using about six bed positions. An OpenPET geometry can extend the axial FOV with a limited number of detectors. The entire whole-body PET scanner must be able to process a large amount of data effectively. In this work, we study feasibility of the fully 3D entire whole-body PET scanner using the GATE simulation. The OpenPET has 12 block detector rings with the ring diameter of 840 mm and each block detector ring consists of 48 depth-of-interaction (DOI) detectors. The OpenPET has the axial length of 895.95 mm with five parts of 58.95 mm open gaps. The OpenPET has higher single data loss than a conventional PET scanner at grouping circuits. NECR of the OpenPET decreases by single data loss. But single data loss is mitigated by separating the axially arranged detector into two parts. Also, multiple coincidences are found to be important for the entire whole-body PET scanner. The entire whole-body PET scanner with the OpenPET geometry promises to provide a large axial FOV with the open space and to have sufficient performance values. But single data loss at the grouping circuits and multiple coincidences are limited to the peak noise equivalent count rate (NECR) for the entire whole-body PET scanner.

Trends in PET imaging

International Nuclear Information System (INIS)

Moses, William W.

2000-01-01

Positron Emission Tomography (PET) imaging is a well established method for obtaining information on the status of certain organs within the human body or in animals. This paper presents an overview of recent trends PET instrumentation. Significant effort is being expended to develop new PET detector modules, especially those capable of measuring depth of interaction. This is aided by recent advances in scintillator and pixellated photodetector technology. The other significant area of effort is development of special purpose PET cameras (such as for imaging breast cancer or small animals) or cameras that have the ability to image in more than one modality (such as PET / SPECT or PET / X-Ray CT)

Diagnostic performance of [18F] FDG PET-CT compared to bone scintigraphy for the detection of bone metastases in lung cancer patients

International Nuclear Information System (INIS)

RODRIGUES, Margarida; STARK, Hannes; RENDL, Gundula; RETTENBACHER, Lukas; PIRICH, Christian; DATZ, Lidwina; STUDNICKA, Michael

2016-01-01

Accurate staging of lung cancer is essential for effective patient management and selection of appropriate therapeutic strategy. The aim of this paper was to compare the value of bone scintigraphy and FDG PET-CT for detecting bone metastases in lung cancer patients and the impact of these modalities in disease staging. One hundred sixty-four lung cancer patients who had undergone both FDG PET-CT and bone scintigraphy within 14 days were included into this study. The analysis of FDG PET-CT and bone scintigraphy was carried out patient- and lesion-based. One hundred twenty-one patients were negative and 43 patients positive for bone metastases. FDG PET-CT found bone metastases in 42/43 patients and bone scintigraphy in 38/43 patients. Sensitivity, specificity and accuracy of FDG PET-CT and bone scintigraphy for detecting bone metastases were 97.7%, 100% and 99.4%, and 87.8%, 97.5% and 94.2%, respectively. FDG PET-CT identified 430 bone metastases and bone scintigraphy 246 bone metastases. Skull was the only region where bone scintigraphy identified more lesions than FDG PET-CT. Based on both scintigraphic modalities disagreement concerning disease stage was found in 3 patients. In conclusion, FDG PET-CT yielded a higher sensitivity, specificity and accuracy than bone scintigraphy for identifying bone metastases in lung cancer patients. FDG PET-CT thus can be recommended for initial staging of lung cancer patients without applying bone scintigraphy for the detection of bone metastases.

Imaging with {sup 124}I in differentiated thyroid carcinoma: is PET/MRI superior to PET/CT?

Energy Technology Data Exchange (ETDEWEB)

Binse, I.; Poeppel, T.D.; Ruhlmann, M.; Gomez, B.; Bockisch, A.; Rosenbaum-Krumme, S.J. [University of Duisburg-Essen, Medical Faculty, Department of Nuclear Medicine, Essen (Germany); Umutlu, L. [University of Duisburg-Essen, Medical Faculty, Department of Radiology, Essen (Germany)

2016-06-15

The aim of this study was to compare integrated PET/CT and PET/MRI for their usefulness in detecting and categorizing cervical iodine-positive lesions in patients with differentiated thyroid cancer using {sup 124}I as tracer. The study group comprised 65 patients at high risk of iodine-positive metastasis who underwent PET/CT (low-dose CT scan, PET acquisition time 2 min; PET/CT{sub 2}) followed by PET/MRI of the neck 24 h after {sup 124}I administration. PET images from both modalities were analysed for the numbers of tracer-positive lesions. Two different acquisition times were used for the comparisons, one matching the PET/CT{sub 2} acquisition time (2 min, PET/MRI{sub 2}) and the other covering the whole MRI scan time (30 min, PET/MRI{sub 30}). Iodine-positive lesions were categorized as metastasis, thyroid remnant or inconclusive according to their location on the PET/CT images. Morphological information provided by MRI was considered for evaluation of lesions on PET/MRI and for volume information. PET/MRI{sub 2} detected significantly more iodine-positive metastases and thyroid remnants than PET/CT{sub 2} (72 vs. 60, p = 0.002, and 100 vs. 80, p = 0.001, respectively), but the numbers of patients with at least one tumour lesion identified were not significantly different (21/65 vs. 17/65 patients). PET/MRI{sub 30} tended to detect more PET-positive metastases than PET/MRI{sub 2} (88 vs. 72), but the difference was not significant (p = 0.07). Of 21 lesions classified as inconclusive on PET/CT, 5 were assigned to metastasis or thyroid remnant when evaluated by PET/MRI. Volume information was available in 34 % of iodine-positive metastases and 2 % of thyroid remnants on PET/MRI. PET/MRI of the neck was found to be superior to PET/CT in detecting iodine-positive lesions. This was attributed to the higher sensitivity of the PET component, Although helpful in some cases, we found no substantial advantage of PET/MRI over PET/CT in categorizing iodine

Imaging corn plants with PhytoPET, a modular PET system for plant biology

Energy Technology Data Exchange (ETDEWEB)

Lee, S.; Kross, B.; McKisson, J.; McKisson, J. E.; Weisenberger, A. G.; Xi, W.; Zorn, C.; Bonito, G.; Howell, C. R.; Reid, C. D.; Crowell, A.; Cumberbatch, L. C.; Topp, C.; Smith, M. F.

2013-11-01

PhytoPET is a modular positron emission tomography (PET) system designed specifically for plant imaging. The PhytoPET design allows flexible arrangements of PET detectors based on individual standalone detector modules built from single Hamamatsu H8500 position sensitive photomultiplier tubes and pixelated LYSO arrays. We have used the PhytoPET system to perform preliminary corn plant imaging studies at the Duke University Biology Department Phytotron. Initial evaluation of the PhytoPET system to image the biodistribution of the positron emitting tracer {sup 11}C in corn plants is presented. {sup 11}CO{sub 2} is loaded into corn seedlings by a leaf-labeling cuvette and translocation of {sup 11}C-sugars is imaged by a flexible arrangement of PhytoPET modules on each side. The PhytoPET system successfully images {sup 11}C within corn plants and allows for the dynamic measurement of {sup 11}C-sugar translocation from the leaf to the roots.

Oncology PET imaging

International Nuclear Information System (INIS)

Inubushi, Masayuki

2014-01-01

At the beginning of this article, likening medical images to 'Where is Waldo?' I indicate the concept of diagnostic process of PET/CT imaging, so that medical physics specialists could understand the role of each imaging modality and infer our distress for image diagnosis. Then, I state the present situation of PET imaging and the basics (e.g. health insurance coverage, clinical significance, principle, protocol, and pitfall) of oncology FDG-PET imaging which accounts for more than 99% of all clinical PET examinations in Japan. Finally, I would like to give a wishful prospect of oncology PET that will expand to be more cancer-specific in order to assess therapeutic effects of emerging molecular targeted drugs targeting the 'hallmarks of cancer'. (author)

Positron range in PET imaging: non-conventional isotopes

International Nuclear Information System (INIS)

Jødal, L; Le Loirec, C; Champion, C

2014-01-01

In addition to conventional short-lived radionuclides, longer-lived isotopes are becoming increasingly important to positron emission tomography (PET). The longer half-life both allows for circumvention of the in-house production of radionuclides, and expands the spectrum of physiological processes amenable to PET imaging, including processes with prohibitively slow kinetics for investigation with short-lived radiotracers. However, many of these radionuclides emit ‘high-energy’ positrons and gamma rays which affect the spatial resolution and quantitative accuracy of PET images. The objective of the present work is to investigate the positron range distribution for some of these long-lived isotopes. Based on existing Monte Carlo simulations of positron interactions in water, the probability distribution of the line of response displacement have been empirically described by means of analytic displacement functions. Relevant distributions have been derived for the isotopes 22 Na, 52 Mn, 89 Zr, 45 Ti, 51 Mn, 94m Tc, 52m Mn, 38 K, 64 Cu, 86 Y, 124 I, and 120 I. It was found that the distribution functions previously found for a series of conventional isotopes (Jødal et al 2012 Phys. Med. Bio. 57 3931–43), were also applicable to these non-conventional isotopes, except that for 120 I, 124 I, 89 Zr, 52 Mn, and 64 Cu, parameters in the formulae were less well predicted by mean positron energy alone. Both conventional and non-conventional range distributions can be described by relatively simple analytic expressions. The results will be applicable to image-reconstruction software to improve the resolution. (paper)

[18F]FDG PET/CT outperforms [18F]FDG PET/MRI in differentiated thyroid cancer

International Nuclear Information System (INIS)

Vrachimis, Alexis; Wenning, Christian; Weckesser, Matthias; Stegger, Lars; Burg, Matthias Christian; Allkemper, Thomas; Schaefers, Michael

2016-01-01

To evaluate the diagnostic potential of PET/MRI with [ 18 F]FDG in comparison to PET/CT in patients with differentiated thyroid cancer suspected or known to have dedifferentiated. The study included 31 thyroidectomized and remnant-ablated patients who underwent a scheduled [ 18 F]FDG PET/CT scan and were then enrolled for a PET/MRI scan of the neck and thorax. The datasets (PET/CT, PET/MRI) were rated regarding lesion count, conspicuity, diameter and characterization. Standardized uptake values were determined for all [ 18 F]FDG-positive lesions. Histology, cytology, and examinations before and after treatment served as the standards of reference. Of 26 patients with a dedifferentiated tumour burden, 25 were correctly identified by both [ 18 F]FDG PET/CT and PET/MRI. Detection rates by PET/CT and PET/MRI were 97 % (113 of 116 lesions) and 85 % (99 of 113 lesions) for malignant lesions, and 100 % (48 of 48 lesions) and 77 % (37 of 48 lesions) for benign lesions, respectively. Lesion conspicuity was higher on PET/CT for both malignant and benign pulmonary lesions and in the overall rating for malignant lesions (p < 0.001). There was a difference between PET/CT and PET/MRI in overall evaluation of malignant lesions (p < 0.01) and detection of pulmonary metastases (p < 0.001). Surgical evaluation revealed three malignant lesions missed by both modalities. PET/MRI additionally failed to detect 14 pulmonary metastases and 11 benign lesions. In patients with thyroid cancer and suspected or known dedifferentiation, [ 18 F]FDG PET/MRI was inferior to low-dose [ 18 F]FDG PET/CT for the assessment of pulmonary status. However, for the assessment of cervical status, [ 18 F]FDG PET/MRI was equal to contrast-enhanced neck [ 18 F]FDG PET/CT. Therefore, [ 18 F]FDG PET/MRI combined with a low-dose CT scan of the thorax may provide an imaging solution when high-quality imaging is needed and high-energy CT is undesirable or the use of a contrast agent is contraindicated. (orig.)

CyberPET: a PET service distributed over a wide area

International Nuclear Information System (INIS)

Pilloy, W.J.; Hellwig, D.; Schaeffer, A.; Hoffmann, P.; Lens, V.

2002-01-01

Aim: Demonstration of bi-directional PET data transmission, interactive display and co-registration, for the purpose of correlative imaging, treatment planning and teaching. Material and Method: In the year 2000, the initial problem to attend was to provide an effective PET service to a hospital (in Luxemburg) which lies 150 km away from a PET center (in another country). Once this solved, the procedure was expanded (in 2001) to co-registration with CT/MRI scans performed locally, and with radiotherapy simulation CT performed in another center 25 km away (in 2002). Equipment from various vendors was used (Siemens, Adac, GE, Hermes). With preliminary agreement of the national medical aid, patients are sent from the Nuclear Medicine Dept of the Centre Hospitalier in Luxemburg (CHL) to the Dept NM of the Saarland University Medical Center for PET examination. The digital data are then sent from the Siemens PET camera to a PC connected to the LAN, and then to a FTP server (Healthnet). The data are similarly collected by a PC of the hospital network in Luxemburg, and transferred to a Hermes NM station. The Dicom PET data are converted on the fly to Interfile, displayed interactively as any other tomographic data, printed and available on the NM image server. Since 2001, the PET data are co-registered with whole-body CT data recorded at CHL according to a specific protocol (see other paper of this group). Now in 2002, we are busy implementing the co-registration of PET data and simulation CT data obtained from the Centre Baclesse (CFB, 25 km from CHL) for the treatment planning of brain tumours (input into an ADAC system). Furthermore, we plan to send the data (after deletion of their digital ID) to a (South African) university which does not yet dispose of a PET camera, to allow the training of their registrars. Results: For the end-user clinician at CHL and CFB , the PET data have the quality of 'live data', which can be examined interactively, along with other imaging

33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. 162.125 Section 162.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.125 Sturgeon Bay and the Sturgeon Bay Ship...

Childhood Attachment to Pets: Associations between Pet Attachment, Attitudes to Animals, Compassion, and Humane Behaviour

Directory of Open Access Journals (Sweden)

Roxanne D. Hawkins

2017-05-01

Full Text Available Attachment to pets has an important role in children’s social, emotional, and cognitive development, mental health, well-being, and quality of life. This study examined associations between childhood attachment to pets and caring and friendship behaviour, compassion, and attitudes towards animals. This study also examined socio-demographic differences, particularly pet ownership and pet type. A self-report survey of over one thousand 7 to 12 year-olds in Scotland, UK, revealed that the majority of children are strongly attached to their pets, but attachment scores differ depending on pet type and child gender. Analysis revealed that attachment to pets is facilitated by compassion and caring and pet-directed friendship behaviours and that attachment to pets significantly predicts positive attitudes towards animals. The findings have implications for the promotion of prosocial and humane behaviour. Encouraging children to participate in pet care behaviour may promote attachment between children and their pet, which in turn may have a range of positive outcomes for both children (such as reduced aggression, better well-being, and quality of life and pets (such as humane treatment. This study enhances our understanding of childhood pet attachment and has implications for humane education and promoting secure emotional attachments in childhood.

Bird surveys at McKinley Bay and Hutchison Bay, Northwest Territories, in 1991

Energy Technology Data Exchange (ETDEWEB)

Cornish, B J; Dickson, D L; Dickson, H L

1992-03-01

McKinley Bay is a shallow protected bay along the eastern Beaufort Sea coast which provides an important habitat for diving ducks. Since 1979, the bay has been the site of a winter harbor and support base for oil and gas exploraton in the Beaufort Sea. Aerial surveys for bird abundance and distribution were conducted in August 1991 as a continuation of long-term monitoring of birds in McKinley Bay and Hutchison Bay, a nearby area used as a control. The main objectives of the 1991 surveys were to expand the set of baseline data on natural annual fluctuations in diving duck numbers, and to determine if numbers of diving ducks had changed since the initial 1981-85 surveys. On the day with the best survey conditions, the population of diving ducks at McKinley bay was estimated at ca 32,000, significantly more than 1981-85. At Hutchison Bay, there were an estimated 11,000 ducks. As in previous years, large numbers of diving ducks were observed off Atkinson Point at the northwest corner of McKinley Bay, at the south end of the bay, and in the northeast corner near a long spit. Most divers in Hutchison Bay were at the west side. Diving ducks, primarily Oldsquaw and scoter, were the most abundant bird group in the study area. Observed distribution patterns of birds are discussed with reference to habitat preferences. 16 refs., 7 figs., 30 tabs.

Pb’s high sedimentation inside the bay mouth of Jiaozhou Bay

Science.gov (United States)

Yang, Dongfang; Miao, Zhenqing; Huang, Xinmin; Wei, Linzhen; Feng, Ming

2017-12-01

Sedimentation is one of the key environmental behaviors of pollutants in the ocean. This paper analyzed the seasonal and temporal variations of Pb’s sedimentation process in Jiaozhou Bay in 1987. Results showed that Pb contents in bottom waters in Jiaozhou Bay in May, July and November 1987 were 1.87-2.60 μg L-1, 15.11-19.68 μg L-1 and 11.08-15.18 μg L-1, and the pollution levels of Pb in May, July and November 1987 were slight, heavy and heavy, respectively. In May 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the middle and inside of the bay mouth. In July and November 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the inside of the bay mouth. The seasonal-temporal variation of sedimentation processes of Pb were determined by the variations of sources input and the vertical water’s effect.

Selecting Safe Pets (For Parents)

Science.gov (United States)

... supplies (pet bowls, pet bed, leash, etc.) as gifts, then selecting the pet as a family. That way, everyone has time to really think about whether your family is ready for a pet. Key Questions Before adopting or purchasing any pet, talk to all family members, discuss ...

Whole-body MRI versus 18F-FDG PET/CT for pretherapeutic assessment and staging of lymphoma: a meta-analysis

Directory of Open Access Journals (Sweden)

Wang D

2018-06-01

Full Text Available Danyang Wang,1 Yanlei Huo,1 Suyun Chen,1 Hui Wang,1 Yingli Ding,2 Xiaochun Zhu,3 Chao Ma1,4 1Department of Nuclear Medicine, Affiliated XinHua Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China; 2Department of Nuclear Medicine, Affiliated Third People’s Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China; 3Department of Nuclear Medicine, Affiliated Ninth People’s Hospital of Shanghai Jiaotong University School of Medicine, Shanghai, China; 4Department of Nuclear Medicine, Tenth People’s Hospital of Tongji University, Shanghai, China Purpose: 18F-fluorodeoxyglucose (18F-FDG positron emission tomography/computed tomography (PET/CT is the reference standard in staging of 18F-FDG-avid lymphomas; however, there is no recommended functional imaging modality for indolent lymphomas. Therefore, we aimed to compare the performance of whole-body magnetic resonance imaging (WB-MRI with that of 18F-FDG PET/CT for lesion detection and initial staging in patients with aggressive or indolent lymphoma. Materials and methods: We searched the MEDLINE, EMBASE, and CENTRAL databases for studies that compared WB-MRI with 18F-FDG PET/CT for lymphoma staging or lesion detection. The methodological quality of the studies was assessed using version 2 of the “Quality Assessment of Diagnostic Accuracy Studies” tool. The pooled staging accuracy (µ of WB-MRI and 18F-FDG PET/CT for initial staging and for assessing possible heterogeneity (χ2 across studies were calculated using commercially available software. Results: Eight studies comprising 338 patients were included. In terms of staging, the meta-analytic staging accuracies of WB-MRI and 18F-FDG PET/CT for Hodgkin lymphoma and aggressive non-Hodgkin lymphoma (NHL were 98% (95% CI, 94%–100% and 98% (95% CI, 94%–100%, respectively. The pooled staging accuracy of 18F-FDG PET/CT dropped to 87% (95% CI, 72%–97% for staging in patients with indolent lymphoma

Diagnostic performance of FDG PET or PET/CT in prosthetic infection after arthroplasty: a meta-analysis

International Nuclear Information System (INIS)

Jin, H.; Yuan, L.; Li, C.; Kan, Y.; Yang, J.; Hao, R.

2014-01-01

The purpose of this study was to systematically review and perform a meta-analysis of published data regarding the diagnostic performance of positron emission tomography (PET) or PET/computed tomography (PET/CT) in prosthetic infection after arthroplasty. A comprehensive computer literature search of studies published through May 31, 2012 regarding PET or PET/CT in patients suspicious of prosthetic infection was performed in PubMed/MEDLINE, Embase and Scopus databases. Pooled sensitivity and specificity of PET or PET/CT in patients suspicious of prosthetic infection on a per prosthesis-based analysis were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of PET or PET/CT in patients with suspicious of prosthetic infection. Fourteen studies comprising 838 prosthesis with suspicious of prosthetic infection after arthroplasty were included in this meta-analysis. The pooled sensitivity of PET or PET/CT in detecting prosthetic infection was 86% (95% confidence interval [CI] 82-90%) on a per prosthesis-based analysis. The pooled specificity of PET or PET/CT in detecting prosthetic infection was 86% (95% CI 83-89%) on a per prosthesis-based analysis. The area under the ROC curve was 0.93 on a per prosthesis-based analysis. In patients suspicious of prosthetic infection, FDG PET or PET/CT demonstrated high sensitivity and specificity. FDG PET or PET/CT are accurate methods in this setting. Nevertheless, possible sources of false positive results and influcing factors should kept in mind.

Diagnostic performance of FDG PET or PET/CT in prosthetic infection after arthroplasty: a meta-analysis.

Science.gov (United States)

Jin, H; Yuan, L; Li, C; Kan, Y; Hao, R; Yang, J

2014-03-01

The purpose of this study was to systematically review and perform a meta-analysis of published data regarding the diagnostic performance of positron emission tomography (PET) or PET/computed tomography (PET/CT) in prosthetic infection after arthroplasty. A comprehensive computer literature search of studies published through May 31, 2012 regarding PET or PET/CT in patients suspicious of prosthetic infection was performed in PubMed/MEDLINE, Embase and Scopus databases. Pooled sensitivity and specificity of PET or PET/CT in patients suspicious of prosthetic infection on a per prosthesis-based analysis were calculated. The area under the receiver-operating characteristic (ROC) curve was calculated to measure the accuracy of PET or PET/CT in patients with suspicious of prosthetic infection. Fourteen studies comprising 838 prosthesis with suspicious of prosthetic infection after arthroplasty were included in this meta-analysis. The pooled sensitivity of PET or PET/CT in detecting prosthetic infection was 86% (95% confidence interval [CI] 82-90%) on a per prosthesis-based analysis. The pooled specificity of PET or PET/CT in detecting prosthetic infection was 86% (95% CI 83-89%) on a per prosthesis-based analysis. The area under the ROC curve was 0.93 on a per prosthesis-based analysis. In patients suspicious of prosthetic infection, FDG PET or PET/CT demonstrated high sensitivity and specificity. FDG PET or PET/CT are accurate methods in this setting. Nevertheless, possible sources of false positive results and influcing factors should kept in mind.

Clinical Applications of FDG PET and PET/CT in Head and Neck Cancer

Directory of Open Access Journals (Sweden)

Akram Al-Ibraheem

2009-01-01

Full Text Available 18F-FDG PET plays an increasing role in diagnosis and management planning of head and neck cancer. Hybrid PET/CT has promoted the field of molecular imaging in head and neck cancer. This modality is particular relevant in the head and neck region, given the complex anatomy and variable physiologic FDG uptake patterns. The vast majority of 18F-FDG PET and PET/CT applications in head and neck cancer related to head and neck squamous cell carcinoma. Clinical applications of 18F-FDG PET and PET/CT in head and neck cancer include diagnosis of distant metastases, identification of synchronous 2nd primaries, detection of carcinoma of unknown primary and detection of residual or recurrent disease. Emerging applications are precise delineation of the tumor volume for radiation treatment planning, monitoring treatment, and providing prognostic information. The clinical role of 18F-FDG PET/CT in N0 disease is limited which is in line with findings of other imaging modalities. MRI is usually used for T staging with an intense discussion concerning the preferable imaging modality for regional lymph node staging as PET/CT, MRI, and multi-slice spiral CT are all improving rapidly. Is this review, we summarize recent literature on 18F-FDG PET and PET/CT imaging of head and neck cancer.

Imaging with PET system

International Nuclear Information System (INIS)

Das, B.K.; Noreen Norfaraheen Lee Abdullah

2012-01-01

PET deals with biochemistry and metabolic changes that occur at molecular level. Hence, PET differs fundamentally from other imaging modalities. CT imaging is based on tissue density, whereas MRI conveys anatomic information based on proton density and proton relaxation dynamics. CT and MRI are useful in clinical diagnosis only when disease process has caused significant anatomic alterations. However, in most disease conditions chemical changes precede anatomic changes, that can be detected by PET technology. Thus, PET can provide earliest and unique information about ongoing disease process long before anatomic or structural changes take place. There is no other modality available at present that can replace PET technology. Although PET produces cross-sectional images like that obtained in MRI or CT, they represent circulation, function and metabolism, and not anatomic structure. PET is extremely sensitive measuring quantitatively concentration of tracers in nano to pico-molar range. Thus, PET enables merger of biochemistry and biology in medicine giving birth to molecular medicine that focuses on identifying the molecular errors of disease leading to developing molecular corrections including gene therapy. Molecular imaging with PET has been playing a role in examining the biological nature of a disease condition and its characterization to guide selection and evaluation of treatment. (author)

Cost-effectiveness of PET and PET/Computed Tomography

DEFF Research Database (Denmark)

Gerke, Oke; Hermansson, Ronnie; Hess, Søren

2015-01-01

measure by means of incremental cost-effectiveness ratios when considering the replacement of the standard regimen by a new diagnostic procedure. This article discusses economic assessments of PET and PET/computed tomography reported until mid-July 2014. Forty-seven studies on cancer and noncancer...

FDG-PET response of skeletal (bone marrow and bone) involvement after induction chemotherapy in pediatric Hodgkin lymphoma - Are specific response criteria required?

Science.gov (United States)

Georgi, Thomas Walter; Kluge, Regine; Kurch, Lars; Chavdarova, Lidia; Hasenclever, Dirk; Stoevesandt, Dietrich; Pelz, Tanja; Landman-Parker, Judith; Wallace, Hamish; Karlen, Jonas; Fernandez-Teijeiro, Ana; Cepelova, Michaela; Fossa, Alexander; Balwierz, Walentyna; Attarbaschi, Andishe; Ammann, Roland A; Pears, Jane; Hraskova, Andrea; Uyttebroeck, Anne; Beishuizen, Auke; Dieckmann, Karin; Leblanc, Thierry; Daw, Stephen; Baumann, Julia; Körholz, Dieter; Sabri, Osama; Mauz-Körholz, Christine

2018-04-13

Purpose: This study focused on skeletal involvement in FDG-PET (PET) in Hodgkin lymphoma (HL). We aimed at a systematic evaluation of the different types of skeletal involvement and their PET response after two cycles of chemotherapy (PET-2), to answer the question whether the current PET response criterion for skeletal involvement is suitable. A secondary objective was to observe the influence of initial uptake intensity and metabolic tumor volume (MTV) of skeletal lesions on the PET-2 response. Methods: Initial PET scans (PET-0) of 1068 pediatric HL patients from the EuroNet-PHL-C1 (C1) trial were evaluated by central review for skeletal involvement. Three types of skeletal lesions were distinguished: skeletal lesions detected only in PET (PETonly), bone marrow (BM) lesions confirmed by MRI or BM biopsy and bone lesions. Uptake intensity (measured as qPET value) and MTV were calculated for each skeletal lesion. All PET-2 scans were assessed for residual tumor activity. The rates of complete metabolic response in PET-2 of skeletal and nodal involvement were compared. Results: 139/1068 (13%) C1 patients showed skeletal involvement (44/139 PETonly patients, 32/139 BM patients and 63/139 bone patients). 101/139 (73%) patients became PET-2 negative in the skeleton while lymph node involvement was PET-2 negative in 94/139 (68%) patients. Highest skeletal PET-2 negative rate was seen in 42/44 (95%) PETonly patients, followed by 22/32 (69%) BM patients and 37/63 (59%) bone patients. Skeletal lesions who became PET-2 negative showed lower median values for initial qPET (2.74) and MTV (2ml) than lesions who remained PET-2 positive (3.84; 7ml). Conclusion: In this study with pediatric HL patients, the complete response rate in PET-2 of skeletal and nodal involvement was similar. Bone flare seemed to be irrelevant. Overall, the current skeletal PET response criterion - comparison with the local skeletal background - is well suited. Initial uptake intensity and MTV of

Choline-PET/CT for imaging prostate cancer; Cholin-PET/CT zur Bildgebung des Prostatakarzinoms

Energy Technology Data Exchange (ETDEWEB)

Krause, Bernd Joachim [Klinik- und Poliklinik fuer Nuklearmedizin, Klinikum rechts der Isar, Technische Univ. Muenchen (Germany); Treiber, U.; Schwarzenboeck, S.; Souvatzoglou, M. [Klinik fuer Urologie, Klinikum rechts der Isar, Technische Univ. Muenchen (Germany)

2010-09-15

PET and PET/CT using [{sup 11}C]- and [{sup 18}F]-labelled choline derivatives are increasingly being used for imaging of prostate cancer. The value of PET and PET/CT with [{sup 11}C]- and [{sup 18}F]-labelled choline derivates in biochemical recurrence of prostate cancer has been examined in many studies and demonstrates an increasing importance. Primary prostate cancer can be detected with moderate sensitivity using PET and PET/CT using [{sup 11}C]- and [{sup 18}F]-labelled choline derivatives - the differentiation between benign prostatic hyperplasia, prostatitis or high-grade intraepithelial neoplasia (HGPIN) is not always possible. At the present time [{sup 11}C]choline PET/CT is not recommended in the primary setting but may be utilized in clinically suspected prostate cancer with repeatedly negative prostate biopsies, in preparation of a focused re-biopsy. Promising results have been obtained for the use of PET and PET/CT with [{sup 11}C]- and [{sup 18}F]-labelled choline derivates in patients with biochemical recurrence. The detection rate of choline PET and PET/CT for local, regional, and distant recurrence in patients with a biochemical recurrence shows a linear correlation with PSA values at the time of imaging and reaches about 75% in patients with PSA > 3 ng/mL. At PSA values below 1 ng/mL, the recurrence can be diagnosed with choline PET/CT in approximately 1/3 of the patients. PET and PET/CT with [{sup 11}C]- and [{sup 18}F]choline derivates can be helpful for choosing a therapeutic strategy in the sense of an individualized treatment: since an early diagnosis of recurrence is crucial to the choice of optimal treatment. The localization of the site of recurrence - local recurrence, lymph node metastasis or systemic dissemination - has important influence on the therapy regimen. (orig.)

Tumor Response and Survival Predicted by Post-Therapy FDG-PET/CT in Anal Cancer

International Nuclear Information System (INIS)

Schwarz, Julie K.; Siegel, Barry A.; Dehdashti, Farrokh; Myerson, Robert J.; Fleshman, James W.; Grigsby, Perry W.

2008-01-01

Purpose: To evaluate the response to therapy for anal carcinoma using post-therapy imaging with positron emission tomography (PET)/computed tomography and F-18 fluorodeoxyglucose (FDG) and to compare the metabolic response with patient outcome. Patients and Methods: This was a prospective cohort study of 53 consecutive patients with anal cancer. All patients underwent pre- and post-treatment whole-body FDG-PET/computed tomography. Patients had been treated with external beam radiotherapy and concurrent chemotherapy. Whole-body FDG-PET was performed 0.9-5.4 months (mean, 2.1) after therapy completion. Results: The post-therapy PET scan did not show any abnormal FDG uptake (complete metabolic response) in 44 patients. Persistent abnormal FDG uptake (partial metabolic response) was found in the anal tumor in 9 patients. The 2-year cause-specific survival rate was 94% for patients with a complete vs. 39% for patients with a partial metabolic response in the anal tumor (p = 0.0008). The 2-year progression-free survival rate was 95% for patients with a complete vs. 22% for patients with a partial metabolic response in the anal tumor (p < 0.0001). A Cox proportional hazards model of survival outcome indicated that a complete metabolic response was the most significant predictor of progression-free survival in our patient population (p = 0.0003). Conclusions: A partial metabolic response in the anal tumor as determined by post-therapy FDG-PET is predictive of significantly decreased progression-free and cause-specific survival after chemoradiotherapy for anal cancer

Efficacy of 18F-FDG PET/CT in investigation of elevated CEA without known primary malignancy

Directory of Open Access Journals (Sweden)

Simon Sin-man Wong

2016-01-01

Full Text Available Aim: To evaluate the efficacy of 18flurodeoxyglucose positron emission tomography/computer tomography (18F-FDG PET/CT in investigating patients with elevated carcinoembryonic antigen (CEA and without known primary malignancy, and the impact of PET/CT findings on patient management. Setting and Design: PET/CT scans done in a tertiary hospital between December 2007 and February 2012 for elevated CEA in patients without known primary malignancy were retrospectively reviewed. Materials and Methods: The PET/CT findings, patients' clinical information, level of CEA, histological diagnosis, and subsequent management were retrieved by the electronic patient record for analysis. Statistical Analysis: Data were analyzed using SPSS version 19. Results: One hundred and one PET/CT scans were performed for patients with elevated CEA. Fifty-eight of these were performed for patients with known primary malignancy and were excluded; 43 PET/CT scans were performed for patients without known primary malignancy and were included. Thirty-three (77% had a positive PET/CT. Among the 32 patients with malignancy, 15 (47% suffered from lung cancer and 8 (25% suffered from colorectal cancer. The sensitivity (97%, specificity (82%, positive predictive value (94%, negative predictive value (90%, and accuracy (93% were calculated. Thirty (91% patients had resultant change in management. The mean CEA level for patients with malignancy (46.1 ng/ml was significantly higher than those without malignancy (3.82 ng/ml (P < 0.05. In predicting the presence of malignancy, a CEA cutoff at 7.55 ng/ml will achieve a sensitivity of 91% and a specificity of 73%. Conclusion: PET/CT, in our study population, appears to be sensitive, specific, and accurate in investigating patients with elevated CEA and without known primary malignancy. In addition to diagnosis of underlying primary malignancy, PET/CT also reveals occult metastases which would affect patient treatment options.Its role in

The impact of 18F-FDG PET on the management of patients with suspected large vessel vasculitis

International Nuclear Information System (INIS)

Fuchs, Martin; Rasch, Helmut; Berg, Scott; Ng, Quinn K.T.; Mueller-Brand, Jan; Walter, Martin A.; Briel, Matthias; Daikeler, Thomas; Tyndall, Alan; Walker, Ulrich A.; Raatz, Heike; Jayne, David; Koetter, Ina; Blockmans, Daniel; Cid, Maria C.; Prieto-Gonzalez, Sergio; Lamprecht, Peter; Salvarani, Carlo; Karageorgaki, Zaharenia; Watts, Richard; Luqmani, Raashid

2012-01-01

We aimed to assess the impact of 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) on the management of patients with suspected large vessel vasculitis. An international expert panel determined diagnoses and clinical management in patients with suspected large vessel vasculitis, with and without the results of 18 F-FDG PET, respectively. The accuracy of the clinical diagnosis and the resulting clinical management with and without the 18 F-FDG PET results were compared using logistic regression models. The analysis included 30 patients referred to a tertiary care centre with large vessel vasculitis and 31 controls. 18 F-FDG PET had an overall sensitivity of 73.3% [95% confidence interval (CI) 54.1-87.7%], a specificity of 83.9% (95% CI 66.3-94.5%), a positive predictive value of 81.5% (95% CI 61.9-93.7%) and a negative predictive value of 76.5% (95% CI 58.8-89.3%). The diagnostic accuracy of 18 F-FDG PET was higher in patients not receiving immunosuppressive drugs (93.3 vs 64.5%, p = 0.006). Taken in context with other available diagnostic modalities, the addition of 18 F-FDG PET increased the clinical diagnostic accuracy from 54.1 to 70.5% (p = 0.04). The addition of 18 F-FDG PET increased the number of indicated biopsies from 22 of 61 patients (36.1%) to 25 of 61 patients (41.0%) and changed the treatment recommendation in 8 of 30 patients (26.7%) not receiving immunosuppressive medication and in 7 of 31 patients (22.6%) receiving immunosuppressive medication. 18 F-FDG PET is a sensitive and specific imaging tool for large vessel vasculitis, especially when performed in patients not receiving immunosuppressive drugs. It increases the overall diagnostic accuracy and has an impact on the clinical management in a significant proportion of patients. (orig.)

Test-retest repeatability of myocardial oxidative metabolism and efficiency using standalone dynamic 11C-acetate PET and multimodality approaches in healthy controls.

Science.gov (United States)

Hansson, Nils Henrik; Harms, Hendrik Johannes; Kim, Won Yong; Nielsen, Roni; Tolbod, Lars P; Frøkiær, Jørgen; Bouchelouche, Kirsten; Poulsen, Steen Hvitfeldt; Wiggers, Henrik; Parner, Erik Thorlund; Sörensen, Jens

2018-05-31

Myocardial efficiency measured by 11 C-acetate positron emission tomography (PET) has successfully been used in clinical research to quantify mechanoenergetic coupling. The objective of this study was to establish the repeatability of myocardial external efficiency (MEE) and work metabolic index (WMI) by non-invasive concepts. Ten healthy volunteers (63 ± 4 years) were examined twice, one week apart, using 11 C-acetate PET, cardiovascular magnetic resonance (CMR), and echocardiography. Myocardial oxygen consumption from PET was combined with stroke work data from CMR, echocardiography, or PET to obtain MEE and WMI for each modality. Repeatability was estimated as the coefficient of variation (CV) between test and retest. MEE CMR , MEE Echo , and MEE PET values were 21.9 ± 2.7%, 16.4 ± 3.7%, and 23.8 ± 4.9%, respectively, P PET values were 4.42 ± 0.90, 4.07 ± 0.63, and 4.58 ± 1.13 mmHg × mL/m 2  × 10 6 , respectively, P = .45. Repeatability for MEE CMR was superior compared with MEE Echo but did not differ significantly compared with MEE PET (6.3% vs 12.9% and 9.4%, P = .04 and .25). CV values for WMI CMR , WMI Echo , and WMI PET were 10.0%, 14.8%, and 12.0%, respectively, (P = .53). Non-invasive measurements of MEE using 11 C-acetate PET are highly repeatable. A PET-only approach did not differ significantly from CMR/PET and might facilitate further clinical research due to lower costs and broader applicability.

[18F]fluoroethylcholine-PET/CT imaging for radiation treatment planning of recurrent and primary prostate cancer with dose escalation to PET/CT-positive lymph nodes

Directory of Open Access Journals (Sweden)

Wahl Andreas

2011-05-01

Full Text Available Abstract Background At present there is no consensus on irradiation treatment volumes for intermediate to high-risk primary cancers or recurrent disease. Conventional imaging modalities, such as CT, MRI and transrectal ultrasound, are considered suboptimal for treatment decisions. Choline-PET/CT might be considered as the imaging modality in radiooncology to select and delineate clinical target volumes extending the prostate gland or prostate fossa. In conjunction with intensity modulated radiotherapy (IMRT and imaged guided radiotherapy (IGRT, it might offer the opportunity of dose escalation to selected sites while avoiding unnecessary irradiation of healthy tissues. Methods Twenty-six patients with primary (n = 7 or recurrent (n = 19 prostate cancer received Choline-PET/CT planned 3D conformal or intensity modulated radiotherapy. The median age of the patients was 65 yrs (range 45 to 78 yrs. PET/CT-scans with F18-fluoroethylcholine (FEC were performed on a combined PET/CT-scanner equipped for radiation therapy planning. The majority of patients had intermediate to high risk prostate cancer. All patients received 3D conformal or intensity modulated and imaged guided radiotherapy with megavoltage cone beam CT. The median dose to primary tumours was 75.6 Gy and to FEC-positive recurrent lymph nodal sites 66,6 Gy. The median follow-up time was 28.8 months. Results The mean SUVmax in primary cancer was 5,97 in the prostate gland and 3,2 in pelvic lymph nodes. Patients with recurrent cancer had a mean SUVmax of 4,38. Two patients had negative PET/CT scans. At 28 months the overall survival rate is 94%. Biochemical relapse free survival is 83% for primary cancer and 49% for recurrent tumours. Distant disease free survival is 100% and 75% for primary and recurrent cancer, respectively. Acute normal tissue toxicity was mild in 85% and moderate (grade 2 in 15%. No or mild late side effects were observed in the majority of patients (84%. One patient had

Clinical evaluation of PET image quality as a function of acquisition time in a new TOF-PET/MR compared to TOF-PET/CT - initial results

International Nuclear Information System (INIS)

Zeimpekis, Konstantinos; Huellner, Martin; De Galiza Barbosa, Felipe; Ter Voert, Edwin; Davison, Helen; Delso, Gaspar; Veit-Haibach, Patrick

2015-01-01

The recently available integrated PET/MR imaging can offer significant additional advances in clinical imaging. The purpose of this study was to compare the PET performance between a PET/CT scanner and an integrated TOF-PET/MR scanner concerning image quality parameters and quantification in terms of SUV as a function of acquisition time (a surrogate of dose). Five brain and five whole body patients were included in the study. The PET/CT scan was used as a reference and the PET/MR acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts and noise were evaluated. SUV measurements were taken in the liver and in white matter to compare quantification. Quantitative evaluation showed good correlation between PET/CT and PET/MR brain SUVs. Liver correlation was lower, with uptake underestimation in PET/MR, partially justified by bio-redistribution. The clinical evaluation showed that PET/MR offers higher image quality and sharpness with lower levels of noise and artefacts compared to PET/CT with reduced acquisition times for whole body scans, while for brain scans there is no significant difference. The PET-component of the TOF-PET/MR showed higher image quality compared to PET/CT as tested with reduced imaging times. However, these results account mainly for body imaging, while no significant difference were found in brain imaging. This overall higher image quality suggests that the acquisition time or injected activity can be reduced by at least 37% on the PET/MR scanner.

Clinical evaluation of PET image quality as a function of acquisition time in a new TOF-PET/MR compared to TOF-PET/CT - initial results

Energy Technology Data Exchange (ETDEWEB)

Zeimpekis, Konstantinos; Huellner, Martin; De Galiza Barbosa, Felipe; Ter Voert, Edwin; Davison, Helen; Delso, Gaspar; Veit-Haibach, Patrick [Nuclear Medicine, University Hospital Zurich (Switzerland)

2015-05-18

The recently available integrated PET/MR imaging can offer significant additional advances in clinical imaging. The purpose of this study was to compare the PET performance between a PET/CT scanner and an integrated TOF-PET/MR scanner concerning image quality parameters and quantification in terms of SUV as a function of acquisition time (a surrogate of dose). Five brain and five whole body patients were included in the study. The PET/CT scan was used as a reference and the PET/MR acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts and noise were evaluated. SUV measurements were taken in the liver and in white matter to compare quantification. Quantitative evaluation showed good correlation between PET/CT and PET/MR brain SUVs. Liver correlation was lower, with uptake underestimation in PET/MR, partially justified by bio-redistribution. The clinical evaluation showed that PET/MR offers higher image quality and sharpness with lower levels of noise and artefacts compared to PET/CT with reduced acquisition times for whole body scans, while for brain scans there is no significant difference. The PET-component of the TOF-PET/MR showed higher image quality compared to PET/CT as tested with reduced imaging times. However, these results account mainly for body imaging, while no significant difference were found in brain imaging. This overall higher image quality suggests that the acquisition time or injected activity can be reduced by at least 37% on the PET/MR scanner.

Clinical Outcomes of Patients Receiving Integrated PET/CT-Guided Radiotherapy for Head and Neck Carcinoma

International Nuclear Information System (INIS)

Vernon, Matthew R.; Maheshwari, Mohit; Schultz, Christopher J.; Michel, Michelle A.; Wong, Stuart J.; Campbell, Bruce H.; Massey, Becky L.; Wilson, J. Frank; Wang Dian

2008-01-01

Purpose: We previously reported the advantages of 18 F-fluorodeoxyglucose-positron emission tomography (PET) fused with CT for radiotherapy planning over CT alone in head and neck carcinoma (HNC). The purpose of this study was to evaluate clinical outcomes and the predictive value of PET for patients receiving PET/CT-guided definitive radiotherapy with or without chemotherapy. Methods and Materials: From December 2002 to August 2006, 42 patients received PET/CT imaging as part of staging and radiotherapy planning. Clinical outcomes including locoregional recurrence, distant metastasis, death, and treatment-related toxicities were collected retrospectively and analyzed for disease-free and overall survival and cumulative incidence of recurrence. Results: Median follow-up from initiation of treatment was 32 months. Overall survival and disease-free survival were 82.8% and 71.0%, respectively, at 2 years, and 74.1% and 66.9% at 3 years. Of the 42 patients, seven recurrences were identified (three LR, one DM, three both LR and DM). Mean time to recurrence was 9.4 months. Cumulative risk of recurrence was 18.7%. The maximum standard uptake volume (SUV) of primary tumor, adenopathy, or both on PET did not correlate with recurrence, with mean values of 12.0 for treatment failures vs. 11.7 for all patients. Toxicities identified in those patients receiving intensity modulated radiation therapy were also evaluated. Conclusions: A high level of disease control combined with favorable toxicity profiles was achieved in a cohort of HNC patients receiving PET/CT fusion guided radiotherapy plus/minus chemotherapy. Maximum SUV of primary tumor and/or adenopathy was not predictive of risk of disease recurrence

Medical application of PET technology

International Nuclear Information System (INIS)

Lim, Sang Moo; Choi, C. W.; An, S. H.; Woo, K. S.; Chung, W. S.; Yang, S. D.; Jun, G. S. and others

1999-04-01

We performed following studies using PET technology: 1. Clinical usefulness of [ 18 F]FDG whole body PET in malignant disease 2. Clinical usefulness of quantitative evaluation of F-18-FDG 3. Pilot study of C-11 methionine PET in brain tumor 4. PET study in patients with Parkinson's disease 5. A study on the clinical myocardial PET image. PET gives various metabolic information for the living human body, and is very important, new diagnostic modality. The PET study will give us the information of cancer patients such as early detection of cancer, staging, recurrence detection and characterization of cancer. The quantitative analysis using PET could be applied to evaluate the pathophysiology of various diseases and develop new drugs and develop new radiopharmaceuticals

Medical application of PET technology

Energy Technology Data Exchange (ETDEWEB)

Lim, Sang Moo; Choi, C. W.; An, S. H.; Woo, K. S.; Chung, W. S.; Yang, S. D.; Jun, G. S. and others

1999-04-01

We performed following studies using PET technology: 1. Clinical usefulness of [{sup 18}F]FDG whole body PET in malignant disease 2. Clinical usefulness of quantitative evaluation of F-18-FDG 3. Pilot study of C-11 methionine PET in brain tumor 4. PET study in patients with Parkinson's disease 5. A study on the clinical myocardial PET image. PET gives various metabolic information for the living human body, and is very important, new diagnostic modality. The PET study will give us the information of cancer patients such as early detection of cancer, staging, recurrence detection and characterization of cancer. The quantitative analysis using PET could be applied to evaluate the pathophysiology of various diseases and develop new drugs and develop new radiopharmaceuticals.

Software-based PET-MR image coregistration: combined PET-MRI for the rest of us

International Nuclear Information System (INIS)

Robertson, Matthew S.; Liu, Xinyang; Vyas, Pranav K.; Safdar, Nabile M.; Plishker, William; Zaki, George F.; Shekhar, Raj

2016-01-01

With the introduction of hybrid positron emission tomography/magnetic resonance imaging (PET/MRI), a new imaging option to acquire multimodality images with complementary anatomical and functional information has become available. Compared with hybrid PET/computed tomography (CT), hybrid PET/MRI is capable of providing superior anatomical detail while removing the radiation exposure associated with CT. The early adoption of hybrid PET/MRI, however, has been limited. To provide a viable alternative to the hybrid PET/MRI hardware by validating a software-based solution for PET-MR image coregistration. A fully automated, graphics processing unit-accelerated 3-D deformable image registration technique was used to align PET (acquired as PET/CT) and MR image pairs of 17 patients (age range: 10 months-21 years, mean: 10 years) who underwent PET/CT and body MRI (chest, abdomen or pelvis), which were performed within a 28-day (mean: 10.5 days) interval. MRI data for most of these cases included single-station post-contrast axial T1-weighted images. Following registration, maximum standardized uptake value (SUV max ) values observed in coregistered PET (cPET) and the original PET were compared for 82 volumes of interest. In addition, we calculated the target registration error as a measure of the quality of image coregistration, and evaluated the algorithm's performance in the context of interexpert variability. The coregistration execution time averaged 97±45 s. The overall relative SUV max difference was 7% between cPET-MRI and PET/CT. The average target registration error was 10.7±6.6 mm, which compared favorably with the typical voxel size (diagonal distance) of 8.0 mm (typical resolution: 0.66 mm x 0.66 mm x 8 mm) for MRI and 6.1 mm (typical resolution: 3.65 mm x 3.65 mm x 3.27 mm) for PET. The variability in landmark identification did not show statistically significant differences between the algorithm and a typical expert. We have presented a software

Software-based PET-MR image coregistration: combined PET-MRI for the rest of us

Energy Technology Data Exchange (ETDEWEB)

Robertson, Matthew S.; Liu, Xinyang; Vyas, Pranav K.; Safdar, Nabile M. [Children' s National Health System, Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington, DC (United States); Plishker, William; Zaki, George F. [IGI Technologies, Inc., College Park, MD (United States); Shekhar, Raj [Children' s National Health System, Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington, DC (United States); IGI Technologies, Inc., College Park, MD (United States)

2016-10-15

With the introduction of hybrid positron emission tomography/magnetic resonance imaging (PET/MRI), a new imaging option to acquire multimodality images with complementary anatomical and functional information has become available. Compared with hybrid PET/computed tomography (CT), hybrid PET/MRI is capable of providing superior anatomical detail while removing the radiation exposure associated with CT. The early adoption of hybrid PET/MRI, however, has been limited. To provide a viable alternative to the hybrid PET/MRI hardware by validating a software-based solution for PET-MR image coregistration. A fully automated, graphics processing unit-accelerated 3-D deformable image registration technique was used to align PET (acquired as PET/CT) and MR image pairs of 17 patients (age range: 10 months-21 years, mean: 10 years) who underwent PET/CT and body MRI (chest, abdomen or pelvis), which were performed within a 28-day (mean: 10.5 days) interval. MRI data for most of these cases included single-station post-contrast axial T1-weighted images. Following registration, maximum standardized uptake value (SUV{sub max}) values observed in coregistered PET (cPET) and the original PET were compared for 82 volumes of interest. In addition, we calculated the target registration error as a measure of the quality of image coregistration, and evaluated the algorithm's performance in the context of interexpert variability. The coregistration execution time averaged 97±45 s. The overall relative SUV{sub max} difference was 7% between cPET-MRI and PET/CT. The average target registration error was 10.7±6.6 mm, which compared favorably with the typical voxel size (diagonal distance) of 8.0 mm (typical resolution: 0.66 mm x 0.66 mm x 8 mm) for MRI and 6.1 mm (typical resolution: 3.65 mm x 3.65 mm x 3.27 mm) for PET. The variability in landmark identification did not show statistically significant differences between the algorithm and a typical expert. We have presented a software

Competitive advantage of PET/MRI

Energy Technology Data Exchange (ETDEWEB)

Jadvar, Hossein, E-mail: jadvar@usc.edu; Colletti, Patrick M.

2014-01-15

Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved.

Competitive advantage of PET/MRI.

Science.gov (United States)

Jadvar, Hossein; Colletti, Patrick M

2014-01-01

Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Competitive advantage of PET/MRI

International Nuclear Information System (INIS)

Jadvar, Hossein; Colletti, Patrick M.

2014-01-01

Multimodality imaging has made great strides in the imaging evaluation of patients with a variety of diseases. Positron emission tomography/computed tomography (PET/CT) is now established as the imaging modality of choice in many clinical conditions, particularly in oncology. While the initial development of combined PET/magnetic resonance imaging (PET/MRI) was in the preclinical arena, hybrid PET/MR scanners are now available for clinical use. PET/MRI combines the unique features of MRI including excellent soft tissue contrast, diffusion-weighted imaging, dynamic contrast-enhanced imaging, fMRI and other specialized sequences as well as MR spectroscopy with the quantitative physiologic information that is provided by PET. Most evidence for the potential clinical utility of PET/MRI is based on studies performed with side-by-side comparison or software-fused MRI and PET images. Data on distinctive utility of hybrid PET/MRI are rapidly emerging. There are potential competitive advantages of PET/MRI over PET/CT. In general, PET/MRI may be preferred over PET/CT where the unique features of MRI provide more robust imaging evaluation in certain clinical settings. The exact role and potential utility of simultaneous data acquisition in specific research and clinical settings will need to be defined. It may be that simultaneous PET/MRI will be best suited for clinical situations that are disease-specific, organ-specific, related to diseases of the children or in those patients undergoing repeated imaging for whom cumulative radiation dose must be kept as low as reasonably achievable. PET/MRI also offers interesting opportunities for use of dual modality probes. Upon clear definition of clinical utility, other important and practical issues related to business operational model, clinical workflow and reimbursement will also be resolved

Validating PET segmentation of thoracic lesions-is 4D PET necessary?

DEFF Research Database (Denmark)

Nielsen, M. S.; Carl, J.

2017-01-01

Respiratory-induced motions are prone to degrade the positron emission tomography (PET) signal with the consequent loss of image information and unreliable segmentations. This phantom study aims to assess the discrepancies relative to stationary PET segmentations, of widely used semiautomatic PET...... segmentation methods on heterogeneous target lesions influenced by motion during image acquisition. Three target lesions included dual F-18 Fluoro-deoxy-glucose (FDG) tracer concentrations as high-and low tracer activities relative to the background. Four different tracer concentration arrangements were...... segmented using three SUV threshold methods (Max40%, SUV40% and 2.5SUV) and a gradient based method (GradientSeg). Segmentations in static 3D-PET scans (PETsta) specified the reference conditions for the individual segmentation methods, target lesions and tracer concentrations. The motion included PET...

FDG PET and PET/CT : EANM procedure guidelines for tumour PET imaging: version 1.0

NARCIS (Netherlands)

Boellaard, Ronald; O'Doherty, Mike J.; Weber, Wolfgang A.; Mottaghy, Felix M.; Lonsdale, Markus N.; Stroobants, Sigrid G.; Oyen, Wim J. G.; Kotzerke, Joerg; Hoekstra, Otto S.; Pruim, Jan; Marsden, Paul K.; Tatsch, Klaus; Hoekstra, Corneline J.; Visser, Eric P.; Arends, Bertjan; Verzijlbergen, Fred J.; Zijlstra, Josee M.; Comans, Emile F. I.; Lammertsma, Adriaan A.; Paans, Anne M.; Willemsen, Antoon T.; Beyer, Thomas; Bockisch, Andreas; Schaefer-Prokop, Cornelia; Delbeke, Dominique; Baum, Richard P.; Chiti, Arturo; Krause, Bernd J.

The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about [18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed

FDG PET and PET/CT: EANM procedure guidelines for tumour PET imaging: version 1.0

NARCIS (Netherlands)

Boellaard, Ronald; O'Doherty, Mike J.; Weber, Wolfgang A.; Mottaghy, Felix M.; Lonsdale, Markus N.; Stroobants, Sigrid G.; Oyen, Wim J. G.; Kotzerke, Joerg; Hoekstra, Otto S.; Pruim, Jan; Marsden, Paul K.; Tatsch, Klaus; Hoekstra, Corneline J.; Visser, Eric P.; Arends, Bertjan; Verzijlbergen, Fred J.; Zijlstra, Josee M.; Comans, Emile F. I.; Lammertsma, Adriaan A.; Paans, Anne M.; Willemsen, Antoon T.; Beyer, Thomas; Bockisch, Andreas; Schaefer-Prokop, Cornelia; Delbeke, Dominique; Baum, Richard P.; Chiti, Arturo; Krause, Bernd J.

2010-01-01

The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about[18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed

FDG PET and PET/CT: EANM procedure guidelines for tumour PET imaging: version 1.0

NARCIS (Netherlands)

Boellaard, R.; O'Doherty, M.J.; Weber, W.A.; Mottaghy, F.M.; Lonsdale, M.N.; Stroobants, S.G.; Oyen, W.J.G.; Kotzerke, J.; Hoekstra, O.S.; Pruim, J.; Marsden, P.K.; Tatsch, K.; Hoekstra, C.J.; Visser, E.P.; Arends, B.; Verzijlbergen, F.J.; Zijlstra, J.M.; Comans, E.F.I.; Lammertsma, A.A.; Paans, A.M.; Willemsen, A.T.; Beyer, T.; Bockisch, A.; Schaefer-Prokop, C.; Delbeke, D.; Baum, R.P.; Chiti, A.; Krause, B.J.

2010-01-01

The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about [18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed

Reproducibility of Quantitative Brain Imaging Using a PET-Only and a Combined PET/MR System

Directory of Open Access Journals (Sweden)

Martin L. Lassen

2017-07-01

Full Text Available The purpose of this study was to test the feasibility of migrating a quantitative brain imaging protocol from a positron emission tomography (PET-only system to an integrated PET/MR system. Potential differences in both absolute radiotracer concentration as well as in the derived kinetic parameters as a function of PET system choice have been investigated. Five healthy volunteers underwent dynamic (R-[11C]verapamil imaging on the same day using a GE-Advance (PET-only and a Siemens Biograph mMR system (PET/MR. PET-emission data were reconstructed using a transmission-based attenuation correction (AC map (PET-only, whereas a standard MR-DIXON as well as a low-dose CT AC map was applied to PET/MR emission data. Kinetic modeling based on arterial blood sampling was performed using a 1-tissue-2-rate constant compartment model, yielding kinetic parameters (K1 and k2 and distribution volume (VT. Differences for parametric values obtained in the PET-only and the PET/MR systems were analyzed using a 2-way Analysis of Variance (ANOVA. Comparison of DIXON-based AC (PET/MR with emission data derived from the PET-only system revealed average inter-system differences of −33 ± 14% (p < 0.05 for the K1 parameter and −19 ± 9% (p < 0.05 for k2. Using a CT-based AC for PET/MR resulted in slightly lower systematic differences of −16 ± 18% for K1 and −9 ± 10% for k2. The average differences in VT were −18 ± 10% (p < 0.05 for DIXON- and −8 ± 13% for CT-based AC. Significant systematic differences were observed for kinetic parameters derived from emission data obtained from PET/MR and PET-only imaging due to different standard AC methods employed. Therefore, a transfer of imaging protocols from PET-only to PET/MR systems is not straightforward without application of proper correction methods.Clinical Trial Registration:www.clinicaltrialsregister.eu, identifier 2013-001724-19

Evaluation of PeneloPET Simulations of Biograph PET/CT Scanners

Science.gov (United States)

Abushab, K. M.; Herraiz, J. L.; Vicente, E.; Cal-González, J.; España, S.; Vaquero, J. J.; Jakoby, B. W.; Udías, J. M.

2016-06-01

Monte Carlo (MC) simulations are widely used in positron emission tomography (PET) for optimizing detector design, acquisition protocols, and evaluating corrections and reconstruction methods. PeneloPET is a MC code based on PENELOPE, for PET simulations which considers detector geometry, acquisition electronics and materials, and source definitions. While PeneloPET has been successfully employed and validated with small animal PET scanners, it required a proper validation with clinical PET scanners including time-of-flight (TOF) information. For this purpose, we chose the family of Biograph PET/CT scanners: the Biograph True-Point (B-TP), Biograph True-Point with TrueV (B-TPTV) and the Biograph mCT. They have similar block detectors and electronics, but a different number of rings and configuration. Some effective parameters of the simulations, such as the dead-time and the size of the reflectors in the detectors, were adjusted to reproduce the sensitivity and noise equivalent count (NEC) rate of the B-TPTV scanner. These parameters were then used to make predictions of experimental results such as sensitivity, NEC rate, spatial resolution, and scatter fraction (SF), from all the Biograph scanners and some variations of them (energy windows and additional rings of detectors). Predictions agree with the measured values for the three scanners, within 7% (sensitivity and NEC rate) and 5% (SF). The resolution obtained for the B-TPTV is slightly better (10%) than the experimental values. In conclusion, we have shown that PeneloPET is suitable for simulating and investigating clinical systems with good accuracy and short computational time, though some effort tuning of a few parameters of the scanners modeled may be needed in case that the full details of the scanners studied are not available.

SU-F-I-57: Evaluate and Optimize PET Acquisition Overlap in 18F-FDG Oncology Wholebody PET/CT: Can We Scan PET Faster?

International Nuclear Information System (INIS)

Zhang, J; Natwa, M; Hall, NC; Knopp, MV; Knopp, MU; Zhang, B; Tung, C

2016-01-01

Purpose: The longer patient has to remain on the table during PET imaging, the higher the likelihood of motion artifacts due to patient discomfort. This study was to investigate and optimize PET acquisition overlap in 18F-FDG oncology wholebody PET/CT to speed up PET acquisition and improve patient comfort. Methods: Wholebody 18F-FDG PET/CT of phantoms, 8 pre-clinical patients (beagles) and 5 clinical oncology patients were performed in 90s/bed on a time-of-flight Gemini TF 64 system. Imaging of phantoms and beagles was acquired with reduced PET overlaps (40%, 33%, 27%, 20%, 13% and no overlap) in addition to the system default (53%). In human studies, 1 or 2 reduced overlaps from the listed options were used to acquire PET/CT sweeps right after the default standard of care imaging. Image quality was blindly reviewed using visual scoring criteria and quantitative SUV assessment. NEMA PET sensitivity was performed under different overlaps. Results: All PET exams demonstrated no significant impact on the visual grades for overlaps >20%. Blinded reviews assigned the best visual scores to PET using overlaps 53%–27%. Reducing overlap to 27% for oncology patients (12-bed) saved an average of ∼40% acquisition time (11min) compared to using the default overlap (18min). No significant SUV variances were found when reducing overlap to half of default for cerebellum, lung, heart, aorta, liver, fat, muscle, bone marrow, thighs and target lesions (p>0.05), except expected variability in urinary system. Conclusion: This study demonstrated by combined phantom, pre-clinical and clinical PET/CT scans that PET acquisition overlap in axial of today’s systems can be reduced and optimized. It showed that a reduction of PET acquisition overlap to 27% (half of system default) can be implemented to reduce table time by ∼40% to improve patient comfort and minimize potential motion artifacts, without prominently degrading image quality or compromising PET quantification.

SU-F-I-57: Evaluate and Optimize PET Acquisition Overlap in 18F-FDG Oncology Wholebody PET/CT: Can We Scan PET Faster?

Energy Technology Data Exchange (ETDEWEB)

Zhang, J; Natwa, M; Hall, NC; Knopp, MV [The Ohio State University, Columbus, OH (United States); Knopp, MU [Pepperdine University, Malibu, CA (United States); Zhang, B; Tung, C [Philips Healthcare, Highland Heights, OH (United States)

2016-06-15

Purpose: The longer patient has to remain on the table during PET imaging, the higher the likelihood of motion artifacts due to patient discomfort. This study was to investigate and optimize PET acquisition overlap in 18F-FDG oncology wholebody PET/CT to speed up PET acquisition and improve patient comfort. Methods: Wholebody 18F-FDG PET/CT of phantoms, 8 pre-clinical patients (beagles) and 5 clinical oncology patients were performed in 90s/bed on a time-of-flight Gemini TF 64 system. Imaging of phantoms and beagles was acquired with reduced PET overlaps (40%, 33%, 27%, 20%, 13% and no overlap) in addition to the system default (53%). In human studies, 1 or 2 reduced overlaps from the listed options were used to acquire PET/CT sweeps right after the default standard of care imaging. Image quality was blindly reviewed using visual scoring criteria and quantitative SUV assessment. NEMA PET sensitivity was performed under different overlaps. Results: All PET exams demonstrated no significant impact on the visual grades for overlaps >20%. Blinded reviews assigned the best visual scores to PET using overlaps 53%–27%. Reducing overlap to 27% for oncology patients (12-bed) saved an average of ∼40% acquisition time (11min) compared to using the default overlap (18min). No significant SUV variances were found when reducing overlap to half of default for cerebellum, lung, heart, aorta, liver, fat, muscle, bone marrow, thighs and target lesions (p>0.05), except expected variability in urinary system. Conclusion: This study demonstrated by combined phantom, pre-clinical and clinical PET/CT scans that PET acquisition overlap in axial of today’s systems can be reduced and optimized. It showed that a reduction of PET acquisition overlap to 27% (half of system default) can be implemented to reduce table time by ∼40% to improve patient comfort and minimize potential motion artifacts, without prominently degrading image quality or compromising PET quantification.

Combined FDG PET/CT imaging for restaging of colorectal cancer patients: impact of image fusion on staging accuracy

International Nuclear Information System (INIS)

Strunk, H.; Jaeger, U.; Flacke, S.; Hortling, N.; Bucerius, J.; Joe, A.; Reinhardt, M.; Palmedo, H.

2005-01-01

Purpose: To evaluate the diagnostic impact of positron emission tomography (PET) with fluorine-18-labeled deoxy-D-glucose (FDG) combined with non-contrast computed tomography (CT) as PET-CT modality in restaging colorectal cancer patients. Material and methods: In this retrospective study, 29 consecutive patients with histologically proven colorectal cancer (17 female, 12 male, aged 51-76 years) underwent whole body scans in one session on a dual modality PET-CT system (Siemens Biograph) 90 min. after i.v. administration of 370 MBq 18 F-FDG. The CT imaging was performed with 40 mAs, 130 kV, slice-thickness 5 mm and without i.v. contrast administration. PET and CT images were reconstructed with a slice-thickness of 5 mm in coronal, sagittal and transverse planes. During a first step of analysis, PET and CT images were scored blinded and independently by a group of two nuclear medicine physicians and a group of two radiologists, respectively. For this purpose, a five-point-scale was used. The second step of data-analysis consisted of a consensus reading by both groups. During the consensus reading, first a virtual (meaning mental) fusion of PET and CT images and afterwards the 'real' fusion (meaning coregistered) PET-CT images were also scored with the same scale. The imaging results were compared with histopathology findings and the course of disease during further follow-up. Results: The total number of malignant lesions detected with the combined PET/CT were 86. For FDG-PET alone it was n=68, and for CT alone n=65. Comparing PET-CT and PET, concordance was found in 81 of 104 lesions. Discrepancies predominantly occurred in the lung, where PET alone often showed true positive results in lymph nodes and soft tissue masses, where CT often was false negative. Comparing mental fusion and 'real' co-registered images, concordance was found in 94 of 104 lesions. In 13 lesions or, respectively, in 7 of 29 patients, a relevant information was gathered using fused images

Interference between PET and MRI sub-systems in a silicon-photomultiplier-based PET/MRI system

International Nuclear Information System (INIS)

Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Hatazawa, Jun; Aoki, Masaaki; Sugiyama, Eiji; Watabe, Tadashi; Imaizumi, Masao; Shimosegawa, Eku

2011-01-01

The silicon-photomultiplier (Si-PM) is a promising photodetector, especially for integrated PET/MRI systems, due to its small size, high gain, and low sensitivity to static magnetic fields. The major problem using a Si-PM-based PET system within the MRI system is the interference between the PET and MRI units. We measured the interference by combining a Si-PM-based PET system with a permanent-magnet MRI system. When the RF signal-induced pulse height exceeded the lower energy threshold level of the PET system, interference between the Si-PM-based PET system and MRI system was detected. The prompt as well as the delayed coincidence count rates of the Si-PM-based PET system increased significantly. These noise counts produced severe artifacts on the reconstructed images of the Si-PM-based PET system. In terms of the effect of the Si-PM-based PET system on the MRI system, although no susceptibility artifact was observed on the MR images, electronic noise from the PET detector ring was detected by the RF coil and reduced the signal-to-noise ratio (S/N) of the MR images. The S/N degradation of the MR images was reduced when the distance between the RF coil and the Si-PM-based PET system was increased. We conclude that reducing the interference between the PET and MRI systems is essential for achieving the optimum performance of integrated Si-PM PET/MRI systems.

[F-18]FDG imaging of head and neck tumors: comparison of hybrid PET, dedicated PET and CT

International Nuclear Information System (INIS)

Dresel, S.; Brinkbaeumer, K.; Schmid, R.; Poepperl, G.; Hahn, K.; Szeimies, U.

2001-01-01

Aim: Aim of the study was to evaluate [F-18]FDG imaging of head and neck tumors using a Hybrid-PET device of the 2nd or 3rd generation. Examinations were compared to dedicated PET and Spiral-CT. Methods: 54 patients suffering from head and neck tumors were examined using dedicated PET and Hybrid-PET after injection of 185-350 MBq [F-18]FDG. Examinations were carried out on the dedicated PET first followed by a scan on the Hybrid-PET. Dedicated PET was acquired in 3D mode, Hybrid-PET was performed in list mode using an axial filter. Reconstruction of data was performed iteratively on both, dedicated PET and Hybrid-PET. All patients received a CT scan in multislice technique. All finding have been verified by the goldstandard histology or in case of negative histology by follow up. Results: Using dedicated PET the primary or recurrent lesion was correctly diagnosed in 47/48 patients, using Hybrid-PET in 46/48 patients and using CT in 25/48 patients. Metastatic disease in cervical lymph nodes was diagnosed in 17/18 patients with dedicated PET, in 16/18 patients with Hybrid-PET and in 15/18 with CT. False positive results with regard to lymph node metastasis were seen with one patient for dedicated PET and Hybrid-PET, respectively, and with 18 patients for CT. In a total of 11 patients unknown metastastic lesions were seen with dedicated PET and with Hybrid-PET elsewhere in the body. Additional malignant disease other than the head and neck tumor was found in 4 patients. Conclusion: Using Hybrid-PET for [F-18]FDG imaging reveals a loss of sensitivity and specificity of about 1-5% as compared to dedicated PET in head and neck tumors. [F-18]FDG PET with both, dedicated PET and Hybrid-PET is superior to CT in the diagnosis of primary or recurrent lesions as well as in the assessment of lymph node involvement. (orig.) [de

The spatial distribution of pet dogs and pet cats on the island of Ireland

Directory of Open Access Journals (Sweden)

More Simon J

2011-06-01

Full Text Available Abstract Background There is considerable international research regarding the link between human demographics and pet ownership. In several international studies, pet ownership was associated with household demographics including: the presence of children in the household, urban/rural location, level of education and age/family structure. What is lacking across all these studies, however, is an understanding of how these pets are spatially distributed throughout the regions under study. This paper describes the spatial distribution of pet dog and pet cat owning households on the island of Ireland. Results In 2006, there were an estimated 640,620 pet dog owning households and 215,542 pet cat owning households in Ireland. These estimates are derived from logistic regression modelling, based on household composition to determine pet dog ownership and the type of house to determine pet cat ownership. Results are presented using chloropleth maps. There is a higher density of pet dog owning households in the east of Ireland and in the cities than the west of Ireland and rural areas. However, in urban districts there are a lower proportion of households owning pet dogs than in rural districts. There are more households with cats in the urban areas, but the proportion of households with cats is greater in rural areas. Conclusions The difference in spatial distribution of dog ownership is a reflection of a generally higher density of households in the east of Ireland and in major cities. The higher proportion of ownership in the west is understandable given the higher proportion of farmers and rural dwellings in this area. Spatial representation allows us to visualise the impact of human household distribution on the density of both pet dogs and pet cats on the island of Ireland. This information can be used when analysing risk of disease spread, for market research and for instigating veterinary care.

FDG PET and PET/CT: EANM procedure guidelines for tumour PET imaging: version 1.0

DEFF Research Database (Denmark)

Boellaard, Ronald; O'Doherty, Mike J; Weber, Wolfgang A

2010-01-01

The aim of this guideline is to provide a minimum standard for the acquisition and interpretation of PET and PET/CT scans with [18F]-fluorodeoxyglucose (FDG). This guideline will therefore address general information about[18F]-fluorodeoxyglucose (FDG) positron emission tomography-computed tomogr...

PET/MR in oncology

DEFF Research Database (Denmark)

Balyasnikova, Svetlana; Löfgren, Johan; de Nijs, Robin

2012-01-01

of the challenges inherent in this new technology, but focus on potential applications for simultaneous PET/MR in the field of oncology. Methods and tracers for use with the PET technology will be familiar to most readers of this journal; thus this paper aims to provide a short and basic introduction to a number...... be applied together with PET increasing the amount of information about the tissues of interest. The potential clinical benefit of applying PET/MR in staging, radiotherapy planning and treatment evaluation in oncology, as well as the research perspectives for the use of PET/MR in the development of new...

Deep-inspiration breath-hold PET/CT versus free breathing PET/CT and respiratory gating PET for reference. Evaluation in 95 patients with lung cancer

International Nuclear Information System (INIS)

Kawano, Tsuyoshi; Ohtake, Eiji; Inoue, Tomio

2011-01-01

The objective of this study was to define the factors that correlate with differences in maximum standardized uptake value (SUV max ) in deep-inspiration breath-hold (DIBH) and free breathing (FB) positron emission tomography (PET)/CT admixed with respiratory gating (RG) PET for reference. Patients (n=95) with pulmonary lesions were evaluated at one facility over 33 months. After undergoing whole-body PET/CT, a RG PET and FB PET/CT scans were obtained, followed by a DIBH PET/CT scan. All scans were recorded using a list-mode dynamic collection method with respiratory gating. The RG PET was reconstructed using phase gating without attenuation correction; the FB PET was reconstructed from the RG PET sinogram datasets with attenuation correction. Respiratory motion distance, breathing cycle speed, and waveform of RG PET were recorded. The SUV max of FB PET/CT and DIBH PET/CT were recorded: the percent difference in SUV max between the FB and DIBH scans was defined as the %BH-index. The %BH-index was significantly higher for lesions in the lower lung area than in the upper lung area. Respiratory motion distance was significantly higher in the lower lung area than in the upper lung area. A significant relationship was observed between the %BH-index and respiratory motion distance. Waveforms without steady end-expiration tended to show a high %BH-index. Significant inverse relationships were observed between %BH-index and cycle speed, and between respiratory motion distance and cycle speed. Decrease in SUV max of FB PET/CT was due to tumor size, distribution of lower lung, long respiratory movement at slow breathing cycle speeds, and respiratory waveforms without steady end-expiration. (author)

Clinical Evaluation of PET Image Quality as a Function of Acquisition Time in a New TOF-PET/MRI Compared to TOF-PET/CT--Initial Results.

Science.gov (United States)

Zeimpekis, Konstantinos G; Barbosa, Felipe; Hüllner, Martin; ter Voert, Edwin; Davison, Helen; Veit-Haibach, Patrick; Delso, Gaspar

2015-10-01

The purpose of this study was to compare only the performance of the PET component between a TOF-PET/CT (henceforth noted as PET/CT) scanner and an integrated TOF-PET/MRI (henceforth noted as PET/MRI) scanner concerning image quality parameters and quantification in terms of standardized uptake value (SUV) as a function of acquisition time (a surrogate of dose). The CT and MR image quality were not assessed, and that is beyond the scope of this study. Five brain and five whole-body patients were included in the study. The PET/CT scan was used as a reference and the PET/MRI acquisition time was consecutively adjusted, taking into account the decay between the scans in order to expose both systems to the same amount of the emitted signal. The acquisition times were then retrospectively reduced to assess the performance of the PET/MRI for lower count rates. Image quality, image sharpness, artifacts, and noise were evaluated. SUV measurements were taken in the liver and in the white matter to compare quantification. Quantitative evaluation showed strong correlation between PET/CT and PET/MRI brain SUVs. Liver correlation was good, however, with lower uptake estimation in PET/MRI, partially justified by bio-redistribution. The clinical evaluation showed that PET/MRI offers higher image quality and sharpness with lower levels of noise and artifacts compared to PET/CT with reduced acquisition times for whole-body scans while for brain scans there is no significant difference. The TOF-PET/MRI showed higher image quality compared to TOF-PET/CT as tested with reduced imaging times. However, this result accounts mainly for body imaging, while no significant differences were found in brain imaging.

Evacuating People and Their Pets: Older Floridians' Need for and Proximity to Pet-Friendly Shelters.

Science.gov (United States)

Douglas, Rachel; Kocatepe, Ayberk; Barrett, Anne E; Ozguven, Eren Erman; Gumber, Clayton

2017-10-04

Pets influence evacuation decisions, but little is known about pet-friendly emergency shelters' availability or older adults' need for them. Our study addresses this issue, focusing on the most densely populated area of Florida (Miami-Dade)-the state with the oldest population and greatest hurricane susceptibility. We use Geographic Information Systems (GIS)-based methodology to identify the shortest paths to pet-friendly shelters, based on distance and congested and uncongested travel times-taking into account the older population's spatial distribution. Logistic regression models using the 2013 American Housing Survey's Disaster Planning Module examine anticipated shelter use as a function of pet ownership and requiring pet evacuation assistance. Thirty-four percent of older adults in the Miami-Dade area have pets-35% of whom report needing pet evacuation assistance. However, GIS accessibility measures show that travel time factors are likely to impede older adults' use of the area's few pet-friendly shelters. Logistic regression results reveal that pet owners are less likely to report anticipating shelter use; however, the opposite holds for pet owners reporting they would need help evacuating their pets-they anticipate using shelters. High pet shelter need coupled with low availability exacerbates older adults' heightened vulnerability during Florida's hurricane season. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Role of FDG-PET and PET/CT in the diagnosis of prolonged febrile states

International Nuclear Information System (INIS)

Jaruskova, M.; Belohlavek, O.

2006-01-01

The role of FDG-PET and PET/CT in patients whose main symptom is prolonged fever has not yet been defined. We addressed this topic in a retrospective study. A total of 124 patients (referred between May 2001 and December 2004) with fever of unknown origin or prolonged fever due to a suspected infection of a joint or vascular prosthesis were included in the study. The patients underwent either FDG-PET or FDG-PET/CT scanning. Sixty-seven patients had a negative focal FDG-PET finding; in this group the method was regarded as unhelpful in determining a diagnosis, and no further investigation was pursued. We tried to obtain clinical confirmation for all patients with positive PET findings. Fifty-seven (46%) patients had positive FDG-PET findings. In six of them no further clinical information was available. Fifty-one patients with positive PET findings and 118 patients in total were subsequently evaluated. Systemic connective tissue disease was confirmed in 17 patients, lymphoma in three patients, inflammatory bowel disease in two patients, vascular prosthesis infection in seven patients, infection of a hip or knee replacement in seven patients, mycotic aneurysm in two patients, abscess in four patients and AIDS in one patient. In eight (16%) patients the finding was falsely positive. FDG-PET or PET/CT contributed to establishing a final diagnosis in 84% of the 51 patients with positive PET findings and in 36% of all 118 evaluated patients with prolonged fever. (orig.)

Bacteriophages safely reduce Salmonella contamination in pet food and raw pet food ingredients.

Science.gov (United States)

Soffer, Nitzan; Abuladze, Tamar; Woolston, Joelle; Li, Manrong; Hanna, Leigh Farris; Heyse, Serena; Charbonneau, Duane; Sulakvelidze, Alexander

2016-01-01

Contamination of pet food with Salmonella is a serious public health concern, and several disease outbreaks have recently occurred due to human exposure to Salmonella tainted pet food. The problem is especially challenging for raw pet foods (which include raw meats, seafood, fruits, and vegetables). These foods are becoming increasingly popular because of their nutritional qualities, but they are also more difficult to maintain Salmonella -free because they lack heat-treatment. Among various methods examined to improve the safety of pet foods (including raw pet food), one intriguing approach is to use bacteriophages to specifically kill Salmonella serotypes. At least 2 phage preparations (SalmoFresh® and Salmonelex™) targeting Salmonella are already FDA cleared for commercial applications to improve the safety of human foods. However, similar preparations are not yet available for pet food applications. Here, we report the results of evaluating one such preparation (SalmoLyse®) in reducing Salmonella levels in various raw pet food ingredients (chicken, tuna, turkey, cantaloupe, and lettuce). Application of SalmoLyse® in low (ca. 2-4×10 6 PFU/g) and standard (ca. 9×10 6 PFU/g) concentrations significantly ( P contamination in all raw foods examined compared to control treatments. When SalmoLyse®-treated (ca. 2×10 7 PFU/g) dry pet food was fed to cats and dogs, it did not trigger any deleterious side effects in the pets. Our data suggest that the bacteriophage cocktail lytic for Salmonella can significantly and safely reduce Salmonella contamination in various raw pet food ingredients.

The onset of deglaciation of Cumberland Bay and Stromness Bay, South Georgia

NARCIS (Netherlands)

Van Der Putten, N.; Verbruggen, C.

Carbon dating of basal peat deposits in Cumberland Bay and Stromness Bay and sediments from a lake in Stromness Bay, South Georgia indicates deglaciation at the very beginning of the Holocene before c. 9500 14C yr BP. This post-dates the deglaciation of one local lake which has been ice-free since

The MiniPET: a didactic PET system

International Nuclear Information System (INIS)

Pedro, R; Silva, J; Maio, A; Gurriana, L; Silva, J M; Augusto, J Soares

2013-01-01

The MiniPET project aims to design and build a small PET system. It consists of two 4 × 4 matrices of 16 LYSO scintillator crystals and two PMTs with 16 channels resulting in a low cost system with the essential functionality of a clinical PET instrument. It is designed to illustrate the physics of the PET technique and to provide a didactic platform for the training of students and nuclear imaging professionals as well as for scientific outreach. The PET modules can be configured to test for the coincidence of 511 keV gamma rays. The model has a flexible mechanical setup [1] and can simulate 14 diferent ring geometries, from a configuration with as few as 18 detectors per ring (ring radius φ=51 mm), up to a geometry with 70 detectors per ring (φ=200 mm). A second version of the electronic system [2] allowed measurement and recording of the energy deposited in 4 detector channels by photons from a 137 Cs radioactive source and by photons resulting of the annihilation of positrons from a 22 Na radioactive source. These energy spectra are used for detector performance studies, as well as angular dependency studies. In this paper, the mechanical setup, the front-end high-speed analog electronics, the digital acquisition and control electronics implemented in a FPGA, as well as the data-transfer interface between the FPGA board and a host PC are described. Recent preliminary results obtained with the 4 active channels in the prototype are also presented.

Recommendations for the use of PET and PET-CT for radiotherapy planning in research projects.

Science.gov (United States)

Somer, E J; Pike, L C; Marsden, P K

2012-08-01

With the increasing use of positron emission tomography (PET) for disease staging, follow-up and therapy monitoring in a number of oncological indications there is growing interest in the use of PET and PET-CT for radiation treatment planning. In order to create a strong clinical evidence base for this, it is important to ensure that research data are clinically relevant and of a high quality. Therefore the National Cancer Research Institute PET Research Network make these recommendations to assist investigators in the development of radiotherapy clinical trials involving the use of PET and PET-CT. These recommendations provide an overview of the current literature in this rapidly evolving field, including standards for PET in clinical trials, disease staging, volume delineation, intensity modulated radiotherapy and PET-augmented planning techniques, and are targeted at a general audience. We conclude with specific recommendations for the use of PET in radiotherapy planning in research projects.

Quantitative simultaneous PET-MR imaging

Science.gov (United States)

Ouyang, Jinsong; Petibon, Yoann; Huang, Chuan; Reese, Timothy G.; Kolnick, Aleksandra L.; El Fakhri, Georges

2014-06-01

Whole-body PET is currently limited by the degradation due to patient motion. Respiratory motion degrades imaging studies of the abdomen. Similarly, both respiratory and cardiac motions significantly hamper the assessment of myocardial ischemia and/or metabolism in perfusion and viability cardiac PET studies. Based on simultaneous PET-MR, we have developed robust and accurate MRI methods allowing the tracking and measurement of both respiratory and cardiac motions during abdominal or cardiac studies. Our list-mode iterative PET reconstruction framework incorporates the measured motion fields into PET emission system matrix as well as the time-dependent PET attenuation map and the position dependent point spread function. Our method significantly enhances the PET image quality as compared to conventional methods.

The usefulness of F-18 FDG whole body PET in the evaluation of postoperative recurrence of cancer

International Nuclear Information System (INIS)

Kang, Won Jun; So, Young; Jeong, Jae Min

1997-01-01

The purpose of this study was to evaluate the usefulness of whole body F-18 FDG PET scan for detecting postoperative recurrence of cancer. One hundred four cancer patients after operation were enrolled (14 brain tumor, 15 head and neck cancer, 23 gynecologic cancer, 16 gastrointestinal cancer, 16 thyroid cancer, and 20 other cancers). Besides conventional images (CI) including CT and MRI, F-18 FDG PET scan was obtained on ECAT EXACT 47 scanner (Siemens- CTI), beginning 60 minutes after injection of 370MBq(10mCi) of F-18 FDG. Regional scan was also obtained with emission image. Transmission images using Ge-68 were carried out for attenuation correction in both whole body and regional images. Findings of PET and CI were confirmed by pathology or clinical follow up. The sensitivity and specificity of PET for detecting recurrence were 94% and 92%, respectively. Contrarily, the sensitivity and specificity of CI were 78% and 68%. CI results were negative and PET results were positive in 11 cases. The biopsy or clinical follow-up of those cases confirmed recurrence of tumor. False negative cases of CI were frequent in patients with gynecologic cancers. Also we measured the serum concentration of tumor markers in patients with gynecologic cancer (CA125), thyroid cancer (thyroglobulin), and colorectal cancer (CEA). The sensitivity and specificity of tumor markers were 71% and 84%, respectively. We conclude that F-18 FDG PET can be used valuably in detecting recurrent foci of a wide variety of malignancy compared to conventional diagnostic methods

Selected PET radiomic features remain the same.

Science.gov (United States)

Tsujikawa, Tetsuya; Tsuyoshi, Hideaki; Kanno, Masafumi; Yamada, Shizuka; Kobayashi, Masato; Narita, Norihiko; Kimura, Hirohiko; Fujieda, Shigeharu; Yoshida, Yoshio; Okazawa, Hidehiko

2018-04-17

We investigated whether PET radiomic features are affected by differences in the scanner, scan protocol, and lesion location using 18 F-FDG PET/CT and PET/MR scans. SUV, TMR, skewness, kurtosis, entropy, and homogeneity strongly correlated between PET/CT and PET/MR images. SUVs were significantly higher on PET/MR 0-2 min and PET/MR 0-10 min than on PET/CT in gynecological cancer ( p = 0.008 and 0.008, respectively), whereas no significant difference was observed between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images in oral cavity/oropharyngeal cancer. TMRs on PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min increased in this order in gynecological cancer and oral cavity/oropharyngeal cancer. In contrast to conventional and histogram indices, 4 textural features (entropy, homogeneity, SRE, and LRE) were not significantly different between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images. 18 F-FDG PET radiomic features strongly correlated between PET/CT and PET/MR images. Dixon-based attenuation correction on PET/MR images underestimated tumor tracer uptake more significantly in oral cavity/oropharyngeal cancer than in gynecological cancer. 18 F-FDG PET textural features were affected less by differences in the scanner and scan protocol than conventional and histogram features, possibly due to the resampling process using a medium bin width. Eight patients with gynecological cancer and 7 with oral cavity/oropharyngeal cancer underwent a whole-body 18 F-FDG PET/CT scan and regional PET/MR scan in one day. PET/MR scans were performed for 10 minutes in the list mode, and PET/CT and 0-2 min and 0-10 min PET/MR images were reconstructed. The standardized uptake value (SUV), tumor-to-muscle SUV ratio (TMR), skewness, kurtosis, entropy, homogeneity, short-run emphasis (SRE), and long-run emphasis (LRE) were compared between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images.

Practical use and implementation of PET in children in a hospital PET centre

DEFF Research Database (Denmark)

Borgwardt, Lise; Larsen, Helle Jung; Pedersen, Kate

2003-01-01

Children are not just small adults-they differ in their psychology, normal physiology and pathophysiology, and various aspects should be considered when planning a positron emission tomography (PET) scan in a child. PET in children is a growing area, and this article describes the practical use...... and implementation of PET in children in a hospital PET centre. It is intended to be of use to nuclear medicine departments implementing or starting to implement PET scans in children. Topics covered are: dealing with children, dosimetry, organisation within the department and relations with other departments......, preparation of the child (provision of information to the child and parents and the fasting procedure), the imaging procedure (resting, tracer injection, positioning, sedation and bladder emptying) and pitfalls in the interpretation of PET scans in children, including experiences with telemedicine....

Practical use and implementation of PET in children in a hospital PET centre

International Nuclear Information System (INIS)

Borgwardt, Lise; Larsen, Helle Jung; Pedersen, Kate; Hoejgaard, Liselotte

2003-01-01

Children are not just small adults - they differ in their psychology, normal physiology and pathophysiology, and various aspects should be considered when planning a positron emission tomography (PET) scan in a child. PET in children is a growing area, and this article describes the practical use and implementation of PET in children in a hospital PET centre. It is intended to be of use to nuclear medicine departments implementing or starting to implement PET scans in children. Topics covered are: dealing with children, dosimetry, organisation within the department and relations with other departments, preparation of the child (provision of information to the child and parents and the fasting procedure), the imaging procedure (resting, tracer injection, positioning, sedation and bladder emptying) and pitfalls in the interpretation of PET scans in children, including experiences with telemedicine. (orig.)

Practical use and implementation of PET in children in a hospital PET centre

Energy Technology Data Exchange (ETDEWEB)

Borgwardt, Lise; Larsen, Helle Jung; Pedersen, Kate; Hoejgaard, Liselotte [Department of Clinical Physiology, Nuclear Medicine and PET, University Hospital of Copenhagen, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen (Denmark)

2003-10-01

Children are not just small adults - they differ in their psychology, normal physiology and pathophysiology, and various aspects should be considered when planning a positron emission tomography (PET) scan in a child. PET in children is a growing area, and this article describes the practical use and implementation of PET in children in a hospital PET centre. It is intended to be of use to nuclear medicine departments implementing or starting to implement PET scans in children. Topics covered are: dealing with children, dosimetry, organisation within the department and relations with other departments, preparation of the child (provision of information to the child and parents and the fasting procedure), the imaging procedure (resting, tracer injection, positioning, sedation and bladder emptying) and pitfalls in the interpretation of PET scans in children, including experiences with telemedicine. (orig.)

Healthy Pets and People

Science.gov (United States)

... prevent the spread of germs between pets and people. Keep pets and their supplies out of the kitchen, and ... a local wildlife rehabilitation facility. More Information Healthy Pets Healthy People Clean Hands Save Lives! Stay Healthy at Animal ...

Diagnostic accuracy of 201thallium-SPECT and 18F-FDG-PET in the clinical assessment of glioma recurrence

International Nuclear Information System (INIS)

Gomez-Rio, Manuel; Rodriguez-Fernandez, Antonio; Ramos-Font, Carlos; Lopez-Ramirez, Escarlata; Llamas-Elvira, Jose M.

2008-01-01

Reliable differential diagnosis between tumour recurrence and treatment-induced lesions is required to take advantage of new therapeutic approaches to recurrent gliomas. Structural imaging methods offer a high sensitivity but a low specificity, which might be improved by neurofunctional imaging. This study aimed to test the hypothesis that incorporation of 18-fluoro-deoxy-glucose positron emission tomography (FDG-PET) increases the accuracy of this differential diagnosis obtained with 201 Tl chloride-single-photon emission computed tomography ( 201 Tl-SPECT). Seventy-six patients (mean age 47.72 ± 16.19 years) under suspicion of glioma recurrence, 42% with low-grade and 58% with high-grade lesions, were studied by 201 Tl-SPECT and FDG-PET, reporting results under blinded conditions using visual analysis. Tumour was confirmed by histological confirmation (23 patients) or clinical and structural neuroimaging follow-up (mean of 2.6 years). This population had a high disease prevalence (72%). Globally, highest sensitivity was obtained using 201 Tl-SPECT assessed with MRI (96%) and highest specificity using FDG-PET + MRI (95%). FDG-PET appeared slightly better for confirming tumour recurrence, whereas 201 Tl-SPECT was superior for ruling out possible recurrence (disease present in 38% of FDG-PET negative explorations). In the high-grade subgroup, there were no false-positive examinations (specificity: 100%), but sensitivity differed among techniques ( 201 Tl-SPECT: 94%; 201 Tl-SPECT + MRI: 97%; FDG-PET + MRI: 83%). In the low-grade subgroup, 201 Tl-SPECT+ MRI showed highest sensitivity (95%) and lowest posttest negative probability (9%); FDG-PET + MRI offered highest specificity (92%) with a posttest negative probability of 35%. FDG-PET does not clearly improve the diagnostic accuracy of 201 Tl-SPECT, which appears to be a more appropriate examination for the diagnosis of possible brain tumour recurrence, especially for ruling it out. (orig.)

Clinical Nononcologic Applications of PET/CT and PET/MRI in Musculoskeletal, Orthopedic, and Rheumatologic Imaging.

Science.gov (United States)

Gholamrezanezhad, Ali; Basques, Kyle; Batouli, Ali; Matcuk, George; Alavi, Abass; Jadvar, Hossein

2018-06-01

With improvements in PET/CT and PET/MRI over the last decade, as well as increased understanding of the pathophysiology of musculoskeletal diseases, there is an emerging potential for PET as a primary or complementary modality in the management of rheumatologic and orthopedic conditions. We discuss the role of PET/CT and PET/MRI in nononcologic musculoskeletal disorders, including inflammatory and infectious conditions and postoperative complications. There is great potential for an increased role for PET to serve as a primary or complementary modality in the management of orthopedic and rheumatologic disorders.

Influence of PET/CT-introduction on PET scanning frequency and indications. Results of a multicenter study

International Nuclear Information System (INIS)

Stergar, H.; Bockisch, A.; Eschmann, S.M.; Krause, B.J.; Roedel, R.; Tiling, R.; Weckesser, M.

2007-01-01

Aim: to evaluate the influence of the introduction of combined PET/CT scanners into clinical routine. This investigation addresses the quantitative changes between PET/CT and stand alone PET. Methods: the study included all examinations performed on stand alone PET- or PET/CT-scanners within 12 month prior to and after implementation of PET/CT. The final data analysis included five university hospitals and a total number of 15 497 exams. We distinguished exams on stand alone tomographs prior to and after installation of the combined device as well as PET/CT scans particularly with regard to disease entities. Various further parameters were investigated. Results: the overall number of PET scans (PET and PET/CT) rose by 146% while the number of scans performed on stand alone scanners declined by 22%. Only one site registered an increase in stand alone PET. The number of exams for staging in oncology increased by 196% while that of cardiac scans decreased by 35% and the number of scans in neurology rose by 47%. The use of scans for radiotherapy planning increased to 7% of all PET/CT studies. The increase of procedures for so-called classic PET oncology indications was moderate compared to the more common tumors. An even greater increase was observed in some rare entities. Conclusions: the introduction of PET/CT led to more than a doubling of overall PET procedures with a main focus on oncology. Some of the observed changes in scanning frequency may be caused by a rising availability of new radiotracers and advancements of competing imaging methods. Nevertheless the evident increase in the use of PET/CT for the most common tumour types demonstrates its expanding role in cancer staging. The combination of molecular and morphologic imaging has not only found its place but is still gaining greater importance with new developments in technology and radiochemistry. (orig.)

Breast cancer detection using high-resolution breast PET compared to whole-body PET or PET/CT

Energy Technology Data Exchange (ETDEWEB)

Kalinyak, Judith E. [Naviscan Inc., San Diego, CA (United States); Berg, Wendie A. [University of Pittsburgh School of Medicine, Magee-Womens Hospital, Pittsburgh, PA (United States); Schilling, Kathy [Boca Raton Regional Hospital, Boca Raton, FL (United States); Madsen, Kathleen S. [Certus International, Inc., St. Louis, MO (United States); Narayanan, Deepa [Naviscan Inc., San Diego, CA (United States); National Cancer Institute, Bethesda, MD (United States); Tartar, Marie [Scripps Clinic, Scripps Green Hospital, La Jolla, CA (United States)

2014-02-15

To compare the performance characteristics of positron emission mammography (PEM) with those of whole-body PET (WBPET) and PET/CT in women with newly diagnosed breast cancer. A total of 178 women consented to PEM for presurgical planning in an IRB-approved protocol and also underwent either WBPET (n = 69) or PET/CT (n = 109) imaging, as per usual care at three centers. Tumor detection sensitivity, positive predictive values, and {sup 18}F-fluorodeoxyglucose (FDG) uptake were compared between the modalities. The effects of tumor size, type, and grade on detection were examined. The chi-squared or Fisher's exact tests were used to compare distributions between groups, and McNemar's test was used to compare distributions for paired data within subject groups, i.e. PEM versus WBPET or PEM versus PET/CT. The mean age of the women was 59 ± 12 years (median 60 years, range 26-89 years), with a mean invasive index tumor size of 1.6 ± 0.8 cm (median 1.5 cm, range 0.5-4.0 cm). PEM detected more index tumors (61/66, 92 %) than WBPET (37/66, 56 %; p < 0.001) or PET/CT (95/109, 87 % vs. 104/109, 95 % for PEM; p < 0.029). Sensitivity for the detection of additional ipsilateral malignancies was also greater with PEM (7/15, 47 %) than with WBPET (1/15, 6.7 %; p = 0.014) or PET/CT (3/23, 13 % vs. 13/23, 57 % for PEM; p = 0.003). Index tumor detection decreased with decreasing invasive tumor size for both WBPET (p = 0.002) and PET/CT (p < 0.001); PEM was not significantly affected (p = 0.20). FDG uptake, quantified in terms of maximum PEM uptake value, was lowest in ductal carcinoma in situ (median 1.5, range 0.7-3.0) and invasive lobular carcinoma (median 1.5, range 0.7-3.4), and highest in grade III invasive ductal carcinoma (median 3.1, range 1.4-12.9). PEM was more sensitive than either WBPET or PET/CT in showing index and additional ipsilateral breast tumors and remained highly sensitive for tumors smaller than 1 cm. (orig.)

Direct comparison of [18F]FDG PET/CT with PET alone and with side-by-side PET and CT in patients with malignant melanoma

International Nuclear Information System (INIS)

Mottaghy, Felix M.; Wohlfart, Petra; Blumstein, Norbert M.; Neumaier, Bernd; Glatting, Gerhard; Buck, Andreas K.; Reske, Sven N.; Sunderkoetter, Cord; Schubert, Roland; Oezdemir, Cueneyt; Scharfetter-Kochanek, Karin

2007-01-01

The purpose of this retrospective, blinded study was to evaluate the additional value of [ 18 F]FDG PET/CT in comparison with PET alone and with side-by-side PET and CT in patients with malignant melanoma (MM). A total of 127 consecutive studies of patients with known MM referred for a whole-body PET/CT examination were included in this study. PET alone, side-by-side PET and CT and integrated PET/CT study were independently and separately interpreted without awareness of the clinical information. One score each was applied for certainty of lesion localisation and for certainty of lesion characterisation. Verification of the findings was subsequently performed using all available clinical, pathological (n = 30) and follow-up information. The number of lesions with an uncertain localisation was significantly (p 18 F]FDG. (orig.)

Combined PET/MRI

DEFF Research Database (Denmark)

Bailey, D L; Pichler, B J; Gückel, B

2018-01-01

The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tübingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants c...... of response to pharmacological interventions and therapies. As such, PET/MRI is a key to advancing medicine and patient care.......The 6th annual meeting to address key issues in positron emission tomography (PET)/magnetic resonance imaging (MRI) was held again in Tübingen, Germany, from March 27 to 29, 2017. Over three days of invited plenary lectures, round table discussions and dialogue board deliberations, participants...... critically assessed the current state of PET/MRI, both clinically and as a research tool, and attempted to chart future directions. The meeting addressed the use of PET/MRI and workflows in oncology, neurosciences, infection, inflammation and chronic pain syndromes, as well as deeper discussions about how...

Local recurrence of prostate cancer after radical prostatectomy is at risk to be missed in {sup 68}Ga-PSMA-11-PET of PET/CT and PET/MRI: comparison with mpMRI integrated in simultaneous PET/MRI

Energy Technology Data Exchange (ETDEWEB)

Freitag, Martin T. [Department of Radiology, German Cancer Research Center, Heidelberg (Germany); Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center, Heidelberg (Germany); Radtke, Jan P. [Department of Radiology, German Cancer Research Center, Heidelberg (Germany); University Hospital Heidelberg, Department of Urology, Heidelberg (Germany); Afshar-Oromieh, Ali; Flechsig, Paul; Giesel, Frederik; Haberkorn, Uwe [University Hospital Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany); Roethke, Matthias C.; Bonekamp, David; Schlemmer, Heinz-Peter [Department of Radiology, German Cancer Research Center, Heidelberg (Germany); Hadaschik, Boris A.; Hohenfellner, Markus [University Hospital Heidelberg, Department of Urology, Heidelberg (Germany); Gleave, Martin [University of British Columbia, The Vancouver Prostate Centre, Vancouver (Canada); Kopka, Klaus; Eder, Matthias [Division of Radiopharmaceutical Chemistry, German Cancer Research Center, Heidelberg (Germany); Heusser, Thorsten; Kachelriess, Marc [Department of Medical Physics in Radiology, German Cancer Research Center, Heidelberg (Germany); Wieczorek, Kathrin [University Hospital Heidelberg, Institute of Pathology, Heidelberg (Germany); Sachpekidis, Christos; Dimitrakopoulou-Strauss, A. [Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center, Heidelberg (Germany)

2017-05-15

The positron emission tomography (PET) tracer {sup 68}Ga-PSMA-11, targeting the prostate-specific membrane antigen (PSMA), is rapidly excreted into the urinary tract. This leads to significant radioactivity in the bladder, which may limit the PET-detection of local recurrence (LR) of prostate cancer (PC) after radical prostatectomy (RP), developing in close proximity to the bladder. Here, we analyze if there is additional value of multi-parametric magnetic resonance imaging (mpMRI) compared to the {sup 68}Ga-PSMA-11-PET-component of PET/CT or PET/MRI to detect LR. One hundred and nineteen patients with biochemical recurrence after prior RP underwent both hybrid {sup 68}Ga-PSMA-11-PET/CT{sub low-dose} (1 h p.i.) and -PET/MRI (2-3 h p.i.) including a mpMRI protocol of the prostatic bed. The comparison of both methods was restricted to the abdomen with focus on LR (McNemar). Bladder-LR distance and recurrence size were measured in axial T2w-TSE. A logistic regression was performed to determine the influence of these variables on detectability in {sup 68}Ga-PSMA-11-PET. Standardized-uptake-value (SUV{sub mean}) quantification of LR was performed. There were 93/119 patients that had at least one pathologic finding. In addition, 18/119 Patients (15.1%) were diagnosed with a LR in mpMRI of PET/MRI but only nine were PET-positive in PET/CT and PET/MRI. This mismatch was statistically significant (p = 0.004). Detection of LR using the PET-component was significantly influenced by proximity to the bladder (p = 0.028). The PET-pattern of LR-uptake was classified into three types (1): separated from bladder; (2): fuses with bladder, and (3): obliterated by bladder. The size of LRs did not affect PET-detectability (p = 0.84), mean size was 1.7 ± 0.69 cm long axis, 1.2 ± 0.46 cm short-axis. SUV{sub mean} in nine men was 8.7 ± 3.7 (PET/CT) and 7.0 ± 4.2 (PET/MRI) but could not be quantified in the remaining nine cases (obliterated by bladder). The present study demonstrates

Late pancreatic metastasis of renal cell carcinoma with absence of FDG-uptake in PET-CT

Directory of Open Access Journals (Sweden)

Elif Karadeli

2016-03-01

Full Text Available The primary tumors, which raise isolated pancreas metastases are frequently of renal origin, where colorectal cancer, melanoma, breast and lung cancers and sarcoma are the following causes of metastatic pancreas cancer . In this article, we present a case of pancreas-metastatic renal cell carcinoma with its radiological features, which did not exert anF-18 FDG-uptake in the whole-body positron emission tomography (PET. [Cukurova Med J 2016; 41(0.100: 92-94

'Serial review on clinical PET tracers'. Application of health insurance of [15O]oxygen PET and [18F]FDG-PET

International Nuclear Information System (INIS)

Torizuka, Kanji

2009-01-01

As regards the application required for health insurance of PET, the Ministry of Health, Labour and Welfare indicates the following procedures: first, request a permission to the Ministry of Health, Labour and Welfare for the clinical use of the automatic synthetic instrument for PET drug, approved according to the Pharmaceutical Affairs Law. Second, put into practice the use of PET test, under the highly advanced medicine premises. Then, in case of gathered positive results, the health insurance is approved for this PET test. Thus, following the above mentioned procedures, first, the use of [ 15 O] oxygen PET was approved in April 1996. Second, the use of [ 18 F]FDG-PET was approved in 12 different diseases: epilepsy, ischemic heart disease and 10 different types of cancer, in April 2002. Third, in April 2006, a additional 3 types of cancer were approved. Now, we are in the process to get the health insurance of all kinds of malignant tumors (cancer and sarcoma) except for the early gastric cancer. (author)

PET studies in epilepsy

Science.gov (United States)

Sarikaya, Ismet

2015-01-01

Various PET studies, such as measurements of glucose, serotonin and oxygen metabolism, cerebral blood flow and receptor bindings are availabe for epilepsy. 18Fluoro-2-deoxyglucose (18F-FDG) PET imaging of brain glucose metabolism is a well established and widely available technique. Studies have demonstrated that the sensitivity of interictal FDG-PET is higher than interictal SPECT and similar to ictal SPECT for the lateralization and localization of epileptogenic foci in presurgical patients refractory to medical treatments who have noncontributory EEG and MRI. In addition to localizing epileptogenic focus, FDG-PET provide additional important information on the functional status of the rest of the brain. The main limitation of interictal FDG-PET is that it cannot precisely define the surgical margin as the area of hypometabolism usually extends beyond the epileptogenic zone. Various neurotransmitters (GABA, glutamate, opiates, serotonin, dopamine, acethylcholine, and adenosine) and receptor subtypes are involved in epilepsy. PET receptor imaging studies performed in limited centers help to understand the role of neurotransmitters in epileptogenesis, identify epileptic foci and investigate new treatment approaches. PET receptor imaging studies have demonstrated reduced 11C-flumazenil (GABAA-cBDZ) and 18F-MPPF (5-HT1A serotonin) and increased 11C-cerfentanil (mu opiate) and 11C-MeNTI (delta opiate) bindings in the area of seizure. 11C-flumazenil has been reported to be more sensitive than FDG-PET for identifying epileptic foci. The area of abnormality on GABAAcBDZ and opiate receptor images is usually smaller and more circumscribed than the area of hypometabolism on FDG images. Studies have demonstrated that 11C-alpha-methyl-L-tryptophan PET (to study synthesis of serotonin) can detect the epileptic focus within malformations of cortical development and helps in differentiating epileptogenic from non-epileptogenic tubers in patients with tuberous sclerosis complex

29 CFR 94.655 - Individual.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Individual. 94.655 Section 94.655 Labor Office of the Secretary of Labor GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Definitions § 94.655 Individual. Individual means a natural person. ...

PeneloPET, a Monte Carlo PET simulation tool based on PENELOPE: features and validation

Energy Technology Data Exchange (ETDEWEB)

Espana, S; Herraiz, J L; Vicente, E; Udias, J M [Grupo de Fisica Nuclear, Departmento de Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, Madrid (Spain); Vaquero, J J; Desco, M [Unidad de Medicina y CirugIa Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain)], E-mail: jose@nuc2.fis.ucm.es

2009-03-21

Monte Carlo simulations play an important role in positron emission tomography (PET) imaging, as an essential tool for the research and development of new scanners and for advanced image reconstruction. PeneloPET, a PET-dedicated Monte Carlo tool, is presented and validated in this work. PeneloPET is based on PENELOPE, a Monte Carlo code for the simulation of the transport in matter of electrons, positrons and photons, with energies from a few hundred eV to 1 GeV. PENELOPE is robust, fast and very accurate, but it may be unfriendly to people not acquainted with the FORTRAN programming language. PeneloPET is an easy-to-use application which allows comprehensive simulations of PET systems within PENELOPE. Complex and realistic simulations can be set by modifying a few simple input text files. Different levels of output data are available for analysis, from sinogram and lines-of-response (LORs) histogramming to fully detailed list mode. These data can be further exploited with the preferred programming language, including ROOT. PeneloPET simulates PET systems based on crystal array blocks coupled to photodetectors and allows the user to define radioactive sources, detectors, shielding and other parts of the scanner. The acquisition chain is simulated in high level detail; for instance, the electronic processing can include pile-up rejection mechanisms and time stamping of events, if desired. This paper describes PeneloPET and shows the results of extensive validations and comparisons of simulations against real measurements from commercial acquisition systems. PeneloPET is being extensively employed to improve the image quality of commercial PET systems and for the development of new ones.

PeneloPET, a Monte Carlo PET simulation tool based on PENELOPE: features and validation

International Nuclear Information System (INIS)

Espana, S; Herraiz, J L; Vicente, E; Udias, J M; Vaquero, J J; Desco, M

2009-01-01

Monte Carlo simulations play an important role in positron emission tomography (PET) imaging, as an essential tool for the research and development of new scanners and for advanced image reconstruction. PeneloPET, a PET-dedicated Monte Carlo tool, is presented and validated in this work. PeneloPET is based on PENELOPE, a Monte Carlo code for the simulation of the transport in matter of electrons, positrons and photons, with energies from a few hundred eV to 1 GeV. PENELOPE is robust, fast and very accurate, but it may be unfriendly to people not acquainted with the FORTRAN programming language. PeneloPET is an easy-to-use application which allows comprehensive simulations of PET systems within PENELOPE. Complex and realistic simulations can be set by modifying a few simple input text files. Different levels of output data are available for analysis, from sinogram and lines-of-response (LORs) histogramming to fully detailed list mode. These data can be further exploited with the preferred programming language, including ROOT. PeneloPET simulates PET systems based on crystal array blocks coupled to photodetectors and allows the user to define radioactive sources, detectors, shielding and other parts of the scanner. The acquisition chain is simulated in high level detail; for instance, the electronic processing can include pile-up rejection mechanisms and time stamping of events, if desired. This paper describes PeneloPET and shows the results of extensive validations and comparisons of simulations against real measurements from commercial acquisition systems. PeneloPET is being extensively employed to improve the image quality of commercial PET systems and for the development of new ones.

75 FR 8297 - Tongass National Forest, Thorne Bay Ranger District, Thorne Bay, AK

Science.gov (United States)

2010-02-24

..., Thorne Bay, AK AGENCY: Forest Service, USDA. ACTION: Cancellation of Notice of intent to prepare an... Roberts, Zone Planner, Thorne Bay Ranger District, Tongass National Forest, P.O. Box 19001, Thorne Bay, AK 99919, telephone: 907-828-3250. SUPPLEMENTARY INFORMATION: The 47,007-acre Kosciusko Project Area is...

77 FR 44140 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

Science.gov (United States)

2012-07-27

... Maple-Oregon Bridges so vehicular traffic congestion would not develop on downtown Sturgeon Bay streets... movement of vehicular traffic in Sturgeon Bay. The Sturgeon Bay Ship Canal is approximately 8.6 miles long... significant increase in vehicular and vessel traffic during the peak tourist and navigation season between...

Is There an Additional Value of 11C-Choline PET-CT to T2-weighted MRI Images in the Localization of Intraprostatic Tumor Nodules?

International Nuclear Information System (INIS)

Van den Bergh, Laura; Koole, Michel; Isebaert, Sofie; Joniau, Steven; Deroose, Christophe M.; Oyen, Raymond; Lerut, Evelyne; Budiharto, Tom; Mottaghy, Felix; Bormans, Guy; Van Poppel, Hendrik; Haustermans, Karin

2012-01-01

Purpose: To investigate the additional value of 11 C-choline positron emission tomography (PET)-computed tomography (CT) to T2-weighted (T2w) magnetic resonance imaging (MRI) for localization of intraprostatic tumor nodules. Methods and Materials: Forty-nine prostate cancer patients underwent T2w MRI and 11 C-choline PET-CT before radical prostatectomy and extended lymphadenectomy. Tumor regions were outlined on the whole-mount histopathology sections and on the T2w MR images. Tumor localization was recorded in the basal, middle, and apical part of the prostate by means of an octant grid. To analyze 11 C-choline PET-CT images, the same grid was used to calculate the standardized uptake values (SUV) per octant, after rigid registration with the T2w MR images for anatomic reference. Results: In total, 1,176 octants were analyzed. Sensitivity, specificity, and accuracy of T2w MRI were 33.5%, 94.6%, and 70.2%, respectively. For 11 C-choline PET-CT, the mean SUV max of malignant octants was significantly higher than the mean SUV max of benign octants (3.69 ± 1.29 vs. 3.06 ± 0.97, p mean values (2.39 ± 0.77 vs. 1.94 ± 0.61, p mean and absolute tumor volume (Spearman r = 0.3003, p = 0.0362). No correlation was found between SUVs and prostate-specific antigen, T-stage or Gleason score. The highest accuracy (61.1%) was obtained with a SUV max cutoff of 2.70, resulting in a sensitivity of 77.4% and a specificity of 44.9%. When both modalities were combined (PET-CT or MRI positive), sensitivity levels increased as a function of SUV max but at the cost of specificity. When only considering suspect octants on 11 C-choline PET-CT (SUV max ≥ 2.70) and T2w MRI, 84.7% of these segments were in agreement with the gold standard, compared with 80.5% for T2w MRI alone. Conclusions: The additional value of 11 C-choline PET-CT next to T2w MRI in detecting tumor nodules within the prostate is limited.

Comparison of the diagnosis using FDG-PET and AC-PET with histopathological features in lung adenocarcinomas

International Nuclear Information System (INIS)

Koizumi, Satoko

2011-01-01

Fluorodeoxyglucose-positron emission tomography (FDG-PET) is a useful tool for lung cancer diagnosis because of its good sensitivity and specificity. However, FDG-PET is problematically causing the false negative in cases of well differentiated lung adenocarcinomas which are low grade malignancies. Acetate (AC)-PET using 11 C-acetate is thought to be a superior detection tool for low grade malignancies. In this study, comparison of each type of PET in relation with histopathological features of lung adenocarcinomas was conducted. Samples obtained from 81 lesions in 75 patients with a lung adenocarcinoma who were operated at various institutions of our collaborators between 2005 and 2009 following FDG-PET and AC-PET procedures were examined. These samples consisted of fifty-seven cases of a well differentiated adenocarcinoma and twenty-four cases of a moderately- or a poorly-differentiated adenocarcinoma. Relationships between the histopathological factors (ly, v, p) as well as the lymphatic microvessel and microvessel densities in a tumor and FDG- and AC-PET findings were evaluated. AC-PET was more sensitive than FDG-PET (0.58 vs 0.74, p=0.0001). FDG-PET showed a correlation with invasiveness of the tumor and intratumoral lymphatic microvessel density (p<0.05). Furthermore, AC-PET possessed a superior sensitivity for the detection of well differentiated adenocarcinomas, and tumors without ly, v, or p factors. In lung adenocarcinoma AC-PET showed better sensitivity than FDG-PET and true positive in all cases of stage I B or more. FDG-PET showed the correlation with the pathological invasiveness (ly, v, p) of a tumor and the intratumoral lymphatic microvessel density. (author)

F-FDG PET/CT (PET/CT) influences management in patients with known or suspected pancreatic cancer

International Nuclear Information System (INIS)

Barber, Thomas W.; Kalff, Victor; Cherk, Martin H.; Yap, Kenneth SK.; Evans, Peter; Kelly, Michael J.

2009-01-01

Full text: Objective: To assess the impact on clinical management of PET/CT in patients with known or suspected pancreatic cancer. Methods: Between April 2006 and September 2008,25 PET/CT scans were performed using a dedicated PET/CT (22 scans) or a coincidence hybrid PET/CT camera (3 scans) in 23 patients with known or suspected pancreatic cancer. 17 scans were performed for initial evaluation and 8 for restaging of disease. The pre-PET/CT management plan and for intent were prospectively recorded in all cases. The post-PET/CT management plan was determined from the medical record and for discussions with treating clinicians. The impact of PET/CT on management was classified as High, Medium, Low or None, defined using ANZAPNM PET data collection project criteria. Follow-up was used to reconcile any discordance between PET/CT and conventional imaging. Results: Overall, PET/CT management impact was classified as high (n equal 7), medium (n equal 4), low (n equal 10) or none (n equal 4). Impact was either high or medium in l l/25 patients (44%) (95% confidence interval; 24 - 64%). Impact was high in 4/17 patients imaged for initial evaluation, predominantly by clarifying equivocal lesions on conventional imaging. In restaged patients, PET/CT impact was high in 3/8, and it correctly modified disease extent in 5/8. In the 16 discordant studies, PET/CT assessment was correct in 10, conventional imaging in 4 and there was insufficient information in 2. Conclusion: PET/CT has high or medium management impact in 44% of patients imaged for known or suspected pancreatic cancer, more commonly during restaging. Discordant PET/CT results were usually correct.

Heart PET scan

Science.gov (United States)

... nuclear medicine scan; Heart positron emission tomography; Myocardial PET scan ... A PET scan requires a small amount of radioactive material (tracer). This tracer is given through a vein (IV), ...

PET-Tool: a software suite for comprehensive processing and managing of Paired-End diTag (PET sequence data

Directory of Open Access Journals (Sweden)

Wei Chia-Lin

2006-08-01

Full Text Available Abstract Background We recently developed the Paired End diTag (PET strategy for efficient characterization of mammalian transcriptomes and genomes. The paired end nature of short PET sequences derived from long DNA fragments raised a new set of bioinformatics challenges, including how to extract PETs from raw sequence reads, and correctly yet efficiently map PETs to reference genome sequences. To accommodate and streamline data analysis of the large volume PET sequences generated from each PET experiment, an automated PET data process pipeline is desirable. Results We designed an integrated computation program package, PET-Tool, to automatically process PET sequences and map them to the genome sequences. The Tool was implemented as a web-based application composed of four modules: the Extractor module for PET extraction; the Examiner module for analytic evaluation of PET sequence quality; the Mapper module for locating PET sequences in the genome sequences; and the ProjectManager module for data organization. The performance of PET-Tool was evaluated through the analyses of 2.7 million PET sequences. It was demonstrated that PET-Tool is accurate and efficient in extracting PET sequences and removing artifacts from large volume dataset. Using optimized mapping criteria, over 70% of quality PET sequences were mapped specifically to the genome sequences. With a 2.4 GHz LINUX machine, it takes approximately six hours to process one million PETs from extraction to mapping. Conclusion The speed, accuracy, and comprehensiveness have proved that PET-Tool is an important and useful component in PET experiments, and can be extended to accommodate other related analyses of paired-end sequences. The Tool also provides user-friendly functions for data quality check and system for multi-layer data management.

Simultaneous PET-MR acquisition and MR-derived motion fields for correction of non-rigid motion in PET

International Nuclear Information System (INIS)

Tsoumpas, C.; Mackewn, J.E.; Halsted, P.; King, A.P.; Buerger, C.; Totman, J.J.; Schaeffter, T.; Marsden, P.K.

2010-01-01

Positron emission tomography (PET) provides an accurate measurement of radiotracer concentration in vivo, but performance can be limited by subject motion which degrades spatial resolution and quantitative accuracy. This effect may become a limiting factor for PET studies in the body as PET scanner technology improves. In this work, we propose a new approach to address this problem by employing motion information from images measured simultaneously using a magnetic resonance (MR) scanner. The approach is demonstrated using an MR-compatible PET scanner and PET-MR acquisition with a purpose-designed phantom capable of non-rigid deformations. Measured, simultaneously acquired MR data were used to correct for motion in PET, and results were compared with those obtained using motion information from PET images alone. Motion artefacts were significantly reduced and the PET image quality and quantification was significantly improved by the use of MR motion fields, whilst the use of PET-only motion information was less successful. Combined PET-MR acquisitions potentially allow PET motion compensation in whole-body acquisitions without prolonging PET acquisition time or increasing radiation dose. This, to the best of our knowledge, is the first study to demonstrate that simultaneously acquired MR data can be used to estimate and correct for the effects of non-rigid motion in PET. (author)

CSF biomarkers of Alzheimer's disease concord with amyloid-β PET and predict clinical progression: A study of fully automated immunoassays in BioFINDER and ADNI cohorts.

Science.gov (United States)

Hansson, Oskar; Seibyl, John; Stomrud, Erik; Zetterberg, Henrik; Trojanowski, John Q; Bittner, Tobias; Lifke, Valeria; Corradini, Veronika; Eichenlaub, Udo; Batrla, Richard; Buck, Katharina; Zink, Katharina; Rabe, Christina; Blennow, Kaj; Shaw, Leslie M

2018-03-01

We studied whether fully automated Elecsys cerebrospinal fluid (CSF) immunoassay results were concordant with positron emission tomography (PET) and predicted clinical progression, even with cutoffs established in an independent cohort. Cutoffs for Elecsys amyloid-β 1-42 (Aβ), total tau/Aβ(1-42), and phosphorylated tau/Aβ(1-42) were defined against [ 18 F]flutemetamol PET in Swedish BioFINDER (n = 277) and validated against [ 18 F]florbetapir PET in Alzheimer's Disease Neuroimaging Initiative (n = 646). Clinical progression in patients with mild cognitive impairment (n = 619) was studied. CSF total tau/Aβ(1-42) and phosphorylated tau/Aβ(1-42) ratios were highly concordant with PET classification in BioFINDER (overall percent agreement: 90%; area under the curve: 94%). The CSF biomarker statuses established by predefined cutoffs were highly concordant with PET classification in Alzheimer's Disease Neuroimaging Initiative (overall percent agreement: 89%-90%; area under the curves: 96%) and predicted greater 2-year clinical decline in patients with mild cognitive impairment. Strikingly, tau/Aβ ratios were as accurate as semiquantitative PET image assessment in predicting visual read-based outcomes. Elecsys CSF biomarker assays may provide reliable alternatives to PET in Alzheimer's disease diagnosis. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Physical processes in a coupled bay-estuary coastal system: Whitsand Bay and Plymouth Sound

Science.gov (United States)

Uncles, R. J.; Stephens, J. A.; Harris, C.

2015-09-01

Whitsand Bay and Plymouth Sound are located in the southwest of England. The Bay and Sound are separated by the ∼2-3 km-wide Rame Peninsula and connected by ∼10-20 m-deep English Channel waters. Results are presented from measurements of waves and currents, drogue tracking, surveys of salinity, temperature and turbidity during stratified and unstratified conditions, and bed sediment surveys. 2D and 3D hydrodynamic models are used to explore the generation of tidally- and wind-driven residual currents, flow separation and the formation of the Rame eddy, and the coupling between the Bay and the Sound. Tidal currents flow around the Rame Peninsula from the Sound to the Bay between approximately 3 h before to 2 h after low water and form a transport path between them that conveys lower salinity, higher turbidity waters from the Sound to the Bay. These waters are then transported into the Bay as part of the Bay-mouth limb of the Rame eddy and subsequently conveyed to the near-shore, east-going limb and re-circulated back towards Rame Head. The Simpson-Hunter stratification parameter indicates that much of the Sound and Bay are likely to stratify thermally during summer months. Temperature stratification in both is pronounced during summer and is largely determined by coastal, deeper-water stratification offshore. Small tidal stresses in the Bay are unable to move bed sediment of the observed sizes. However, the Bay and Sound are subjected to large waves that are capable of driving a substantial bed-load sediment transport. Measurements show relatively low levels of turbidity, but these respond rapidly to, and have a strong correlation with, wave height.

Qualification test of a MPPC-based PET module for future MRI-PET scanners

Science.gov (United States)

Kurei, Y.; Kataoka, J.; Kato, T.; Fujita, T.; Funamoto, H.; Tsujikawa, T.; Yamamoto, S.

2014-11-01

We have developed a high-resolution, compact Positron Emission Tomography (PET) module for future use in MRI-PET scanners. The module consists of large-area, 4×4 ch MPPC arrays (Hamamatsu S11827-3344MG) optically coupled with Ce:LYSO scintillators fabricated into 12×12 matrices of 1×1 mm2 pixels. At this stage, a pair of module and coincidence circuits was assembled into an experimental prototype gantry arranged in a ring of 90 mm in diameter to form the MPPC-based PET system. The PET detector ring was then positioned around the RF coil of the 4.7 T MRI system. We took an image of a point 22Na source under fast spin echo (FSE) and gradient echo (GE), in order to measure interference between the MPPC-based PET and the MRI. We only found a slight degradation in the spatial resolution of the PET image from 1.63 to 1.70 mm (FWHM; x-direction), or 1.48-1.55 mm (FWHM; y-direction) when operating with the MRI, while the signal-to-noise ratio (SNR) of the MRI image was only degraded by 5%. These results encouraged us to develop a more advanced version of the MRI-PET gantry with eight MPPC-based PET modules, whose detailed design and first qualification test are also presented in this paper.

Pet exposure and risk of atopic dermatitis at the pediatric age: a meta-analysis of birth cohort studies.

Science.gov (United States)

Pelucchi, Claudio; Galeone, Carlotta; Bach, Jean-François; La Vecchia, Carlo; Chatenoud, Liliane

2013-09-01

Findings on pet exposure and the risk of atopic dermatitis (AD) in children are inconsistent. With the aim to summarize the results of exposure to different pets on AD, we undertook a meta-analysis of epidemiologic studies on this issue. In August 2012, we conducted a systematic literature search in Medline and Embase. We included analytic studies considering exposure to dogs, cats, other pets, or pets overall during pregnancy, infancy, and/or childhood, with AD assessment performed during infancy or childhood. We calculated summary relative risks and 95% CIs using both fixed- and random-effects models. We computed summary estimates across selected subgroups. Twenty-six publications from 21 birth cohort studies were used in the meta-analyses. The pooled relative risks of AD for exposure versus no exposure were 0.72 (95% CI, 0.61-0.85; I(2) = 46%; results based on 15 studies) for exposure to dogs, 0.94 (95% CI, 0.76-1.16; I(2) = 54%; results based on 13 studies) for exposure to cats, and 0.75 (95% CI, 0.67-0.85; I(2) = 54%; results based on 11 studies) for exposure to pets overall. No heterogeneity emerged across the subgroups examined, except for geographic area. This meta-analysis reported a favorable effect of exposure to dogs and pets on the risk of AD in infants or children, whereas no association emerged with exposure to cats. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Feasibility of simultaneous PET/MR of the carotid artery: first clinical experience and comparison to PET/CT

DEFF Research Database (Denmark)

Ripa, Rasmus Sejersten; Knudsen, Andreas; Hag, Anne Mette Fisker

2013-01-01

The study aimed at comparing PET/MR to PET/CT for imaging the carotid arteries in patients with known increased risk of atherosclerosis. Six HIV-positive men underwent sequential PET/MR and PET/CT of the carotid arteries after injection of 400 MBq of 18F-FDG. PET/MR was performed a median of 131......) indicating that the luminal 18F-FDG content had minimal influence on the values. The study shows for the first time that simultaneous PET/MR of the carotid arteries is feasible in patients with increased risk of atherosclerosis. Quantification of 18F-FDG uptake correlated well between PET/MR and PET...

7 CFR 400.94 - Mediation.

Science.gov (United States)

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Mediation. 400.94 Section 400.94 Agriculture... AGRICULTURE GENERAL ADMINISTRATIVE REGULATIONS Appeal Procedure § 400.94 Mediation. For adverse decisions only: (a) Appellants have the right to seek mediation or other forms of alternative dispute resolution in...

18F-fluorodeoxyglucose PET and PET-CT in early detection of cancer recurrent

International Nuclear Information System (INIS)

Xing Yan; Zhao Jinhua

2007-01-01

Early detection of recurrent can improve prognosis and survival of patients with cancer. 18 F- fluorodeoxyglucose( 18 F-FDG) PET can detect metabolic changes before structural changes. The fused imaging provided by PET-CT can precisely localize the foci and demonstrate the complementary roles of functional and anatomic assessments in the diagnosis of cancer recurrence. In addition to the accurate diagnosis and definition of the whole extent of recurrent cancer, 18 F-FDG PET and PET-CT can impact patients management. (authors)

Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET/CT) Findings in an Unusual Case of Multiple Myeloma Presenting with a Large Extra-Axial Intracranial Mass.

Science.gov (United States)

Ayaz, Sevin; Ayaz, Ümit Yaşar

2016-01-01

We aimed to present unusual cranial FDG PET/CT findings of a 56-year-old female with multiple myeloma (MM). Plain CT images revealed a lytic lesion in the right parietal bone, filled with an oval-shaped, large, extra-axial, extradural, intracranial mass which measured 75×75×40 mm and had smooth borders. The right parietal lobe was compressed by the mass. The maximum standardized uptake value (SUV max ) of the mass lesion was 8.94 on FDG PET/CT images. Multiple lytic lesions with an increased uptake were also detected in other calvarial bones, in several vertebras and in the proximal left femur. After seven months, a control FDG PET/CT following radiotherapy and chemotherapy revealed almost complete regression of the right parietal extra-axial mass lesion. The number, size and metabolism of lytic lesions in other bones also decreased. FDG PET/CT was useful for an initial evaluation of MM lesions and was effective in monitoring the response of these lesions to therapy.

Diagnostic accuracy of (18F-FDG PET/CT for the detection of peritoneal carcinomatosis of colorectal origins

Directory of Open Access Journals (Sweden)

Bullier E

2013-03-01

Full Text Available Purpose: to evaluate the diagnostic accuracy of (18 F-FDG positron emission tomography/ computerized tomography (PET/CT for the detection of peritoneal carcinomatosis (PC of colorectal cancer (CRC. Methods: one hundred and forty six eligible patients referred for a PET/CT to evaluate CRC at a single institution were included consecutively and retrospectively. After joint training on 20 similar patient files, two nuclear physicians reviewed the PET/CT scans blindly and independently using a method specifically designed for PC detection. The gold standard was either histological results from surgical exploration for resected patients (n=65 or clinical follow up defined as the 3-month CT follow up supplemented by one year of clinical information and CT monitoring for non-resected patients (n=81. As secondary objectives we evaluated the interobserver reliability between the two PET/CT readings and the diagnostic accuracy of a contemporary ceCT (n=69 or CT component of the PET/CT (n=77 reviewed by an independent radiologist . The extent of PC according to a simplified Sugarbaker index (PCI was examined for the operated subgroup, when PCI was available from the surgeon and PET/CT (n=12. Results: according to the gold standard, 35/146 patients had PC (including 19 of 65 patients with histological gold standard and 16 of 81 patients with clinical follow up gold standard. Sensitivity and specificity of PET/CT were 88% and 96% respectively and positive and negative predictive values and accuracy, 88%, 96% and 94% respectively. For CT alone, the corresponding values were: 68%, 92%, 72%, 90% and 86%. The interobserver agreement for the detection of peritoneal carcinomatosis in PET/CT showed high agreement at 0.91 (Kappa. Median PCI was 3 [range: 1–13] when assessed by surgeons and 4 [range: 1–10] on PET/CT. Focal uptake was the most frequently observed sign on PET. Conclusions: PET/CT appears to be an accurate and reproducible test for PC diagnosis in

PET/MRI. Challenges, solutions and perspectives

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Herzog, Hans [Forschungszentrum Juelich (Germany). Inst. of Neuroscience and Medicine - 4

2012-07-01

Already from the start of PET/CT integrating positron emission tomography (PET) and computed tomography (CT) in one instrument, there have been considerations how to combine PET and magnetic resonance imaging (MRI) so that their complementary abilities can be utilized in a single investigation. Since classical PET electronics fail in an even weak magnetic field and PET signal processing might disturb high-frequency signals of MRI, it soon became clear that new solutions had to be found to avoid mutual interferences. During the last fifteen years a number of different approaches towards PET/MRI for small animal imaging have been developed by research groups which together with their specific features are summarized in this review. Recently, PET/MRI for human imaging became available as well - this time by industrial initiatives. First some prototypes of BrainPET/MRI were developed followed by commercial products for simultaneous and non-simultaneous whole-body PET/MRI. Although only PET/MRI integrated in one scanner offers the full diversity of complementary multiparametric imaging, there are also promising applications of non-simultaneous sequential PET/MRI. While describing the present instrumentation for human PET/MRI, this review discusses the challenges and promises related to this new imaging technology. (orig.)

Adenocarcinoma Prostate With Neuroendocrine Differentiation: Potential Utility of 18F-FDG PET/CT and 68Ga-DOTANOC PET/CT Over 68Ga-PSMA PET/CT.

Science.gov (United States)

Parida, Girish Kumar; Tripathy, Sarthak; Datta Gupta, Shreya; Singhal, Abhinav; Kumar, Rakesh; Bal, Chandrasekhar; Shamim, Shamim Ahmed

2018-04-01

Ga-PSMA PET/CT is the upcoming imaging modality for staging, restaging and response assessment of prostate cancer. However, due to neuroendocrine differentiation in some of patients with prostate cancer, they express somatostatin receptors instead of prostate specific membrane antigen. This can be exploited and other modalities like Ga-DOTANOC PET/CT and F-FDG PET/CT should be used in such cases for guiding management. We hereby discuss a similar case of 67-year-old man of adenocarcinoma prostate with neuroendocrine differentiation, which shows the potential pitfall of Ga-PSMA PET/CT imaging and benefit of Ga-DOTANOC PET/CT and F-FDG PET/CT in such cases.

Molecular Imaging in Breast Cancer: From Whole-Body PET/CT to Dedicated Breast PET

Directory of Open Access Journals (Sweden)

B. B. Koolen

2012-01-01

Full Text Available Positron emission tomography (PET, with or without integrated computed tomography (CT, using 18F-fluorodeoxyglucose (FDG is based on the principle of elevated glucose metabolism in malignant tumors, and its use in breast cancer patients is frequently being investigated. It has been shown useful for classification, staging, and response monitoring, both in primary and recurrent disease. However, because of the partial volume effect and limited resolution of most whole-body PET scanners, sensitivity for the visualization of small tumors is generally low. To improve the detection and quantification of primary breast tumors with FDG PET, several dedicated breast PET devices have been developed. In this nonsystematic review, we shortly summarize the value of whole-body PET/CT in breast cancer and provide an overview of currently available dedicated breast PETs.

Low-dose non-enhanced CT versus full-dose contrast-enhanced CT in integrated PET/CT studies for the diagnosis of uterine cancer recurrence

Energy Technology Data Exchange (ETDEWEB)

Kitajima, Kazuhiro [Institute of Biomedical Research and Innovation, Department of PET Diagnosis, Kobe (Japan); Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Suzuki, Kayo [Institute of Biomedical Research and Innovation, Department of PET Diagnosis, Kobe (Japan); Nakamoto, Yuji [Kyoto University Hospital, Department of Diagnostic Radiology, Kyoto (Japan); Onishi, Yumiko; Sakamoto, Setsu; Sugimura, Kazuro [Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Senda, Michio [Institute of Biomedical Research and Innovation, Department of Molecular Imaging, Kobe (Japan); Kita, Masato [Kobe City Medical Center General Hospital, Department of Obstetrics and Gynecology, Kobe (Japan)

2010-08-15

To evaluate low-dose non-enhanced CT (ldCT) and full-dose contrast-enhanced CT (ceCT) in integrated {sup 18}F-fluorodeoxyglucose (FDG) PET/CT studies for restaging of uterine cancer. A group of 100 women who had undergone treatment for uterine cervical (n=55) or endometrial cancer (n=45) underwent a conventional PET/CT scans with ldCT, and then a ceCT scan. Two observers retrospectively reviewed and interpreted the PET/ldCT and PET/ceCT images in consensus using a three-point grading scale (negative, equivocal, or positive) per patient and per lesion. Final diagnoses were obtained by histopathological examination, or clinical follow-up for at least 6 months. Patient-based analysis showed that the sensitivity, specificity and accuracy of PET/ceCT were 90% (27/30), 97% (68/70) and 95% (95/100), respectively, whereas those of PET/ldCT were 83% (25/30), 94% (66/70) and 91% (91/100), respectively. Sensitivity, specificity and accuracy did not significantly differ between two methods (McNemar test, p=0.48, p=0.48, and p=0.13, respectively). There were 52 sites of lesion recurrence: 12 pelvic lymph node (LN), 11 local recurrence, 8 peritoneum, 7 abdominal LN, 5 lung, 3 supraclavicular LN, 3 liver, 2 mediastinal LN, and 1 muscle and bone. The grading results for the 52 sites of recurrence were: negative 5, equivocal 0 and positive 47 for PET/ceCT, and negative 5, equivocal 4 and positive 43 for PET/ldCT, respectively. Four equivocal regions by PET/ldCT (local recurrence, pelvic LN metastasis, liver metastasis and muscle metastasis) were correctly interpreted as positive by PET/ceCT. PET/ceCT is an accurate imaging modality for the assessment of uterine cancer recurrence. Its use reduces the frequency of equivocal interpretations. (orig.)

[11C]Choline PET/CT predicts survival in hormone-naive prostate cancer patients with biochemical failure after radical prostatectomy

International Nuclear Information System (INIS)

Giovacchini, Giampiero; Incerti, Elena; Mapelli, Paola; Gianolli, Luigi; Picchio, Maria; Kirienko, Margarita; Briganti, Alberto; Gandaglia, Giorgio; Montorsi, Francesco

2015-01-01

Over the last decade, PET/CT with radiolabelled choline has been shown to be useful for restaging patients with prostate cancer (PCa) who develop biochemical failure. The limitations of most clinical studies have been poor validation of [ 11 C]choline PET/CT-positive findings and lack of survival analysis. The aim of this study was to assess whether [ 11 C]choline PET/CT can predict survival in hormone-naive PCa patients with biochemical failure. This retrospective study included 302 hormone-naive PCa patients treated with radical prostatectomy who underwent [ 11 C]choline PET/CT from 1 December 2004 to 31 July 2007 because of biochemical failure (prostate-specific antigen, PSA, >0.2 ng/mL). Median PSA was 1.02 ng/mL. PCa-specific survival was estimated using Kaplan-Meier curves. Cox regression analysis was used to evaluate the association between clinicopathological variables and PCa-specific survival. The coefficients of the covariates included in the Cox regression analysis were used to develop a novel nomogram. Median follow-up was 7.2 years (1.4 - 18.9 years). [ 11 C]Choline PET/CT was positive in 101 of 302 patients (33 %). Median PCa-specific survival after prostatectomy was 14.9 years (95 % CI 9.7 - 20.1 years) in patients with positive [ 11 C]choline PET/CT. Median survival was not achieved in patients with negative [ 11 C]choline PET/CT. The 15-year PCa-specific survival probability was 42.4 % (95 % CI 31.7 - 53.1 %) in patients with positive [ 11 C]choline PET/CT and 95.5 % (95 % CI 93.5 - 97.5 %) in patients with negative [ 11 C]choline PET/CT. In multivariate analysis, [ 11 C]choline PET/CT (hazard ratio 6.36, 95 % CI 2.14 - 18.94, P < 0.001) and Gleason score >7 (hazard ratio 3.11, 95 % CI 1.11 - 8.66, P = 0.030) predicted PCa-specific survival. An internally validated nomogram predicted 15-year PCa-specific survival probability with an accuracy of 80 %. Positive [ 11 C]choline PET/CT after biochemical failure predicts PCa-specific survival in hormone

Diagnostic value of FDG PET-CT for detecting primary breast malignancy: comparison with other image modalities and histopathologic correlation

International Nuclear Information System (INIS)

Jung, Na Young; Lee, Jae Hee; Kim, Chung Ho; Yoo, Ie Ryung; Kim, Sung Hoon; Chung, Yong An; Sohn, Hyung Sun; Chung, Soo Kyo; Jung, Sang Seol

2004-01-01

To compare the diagnostic value of 18F-FDG PET-CT in detecting the primary breast malignancy with other imaging modalities and to determine whether detectability of PET-CT depends on any factors such as size, differentiation, or nuclear grade of tumor. We evaluated pathologically proven 66 lesions in 61 patients (26-74 years, mean 46.9) who underwent preoperative PET-CT. Other imaging modalities were also evaluated: mammography in 58, US in 49 and MRI in 16. PET-CT images were visually evaluated and peak and mean SUV of mass were measured. For mammography and US, category 4 and 5 lesions as positive, and category 0-3 lesions as negative. For MRI, we used morphology and dynamic kinetic curve data based scoring system; sum of the scores higher than 10 as positive. Sensitivities of each modality were obtained. We analyzed PET-CT positive and negative groups in relation to size, SUV, differentiation and nuclear grade of tumors using paired t-test and Fisher's exact test. 65 among 66 were malignant lesions: invasive ductal carcinoma (n=56), ductal carcinoma in situ (n=3), tubular carcinoma (n=1), medullary carcinoma(n=3), mucinous carcinoma(n=1) and malignant fibrous histiocytoma (n=1). One lesion was benign lesion. Sensitivities of PET-CT, mammography, US, and MRI for detecting malignant mass were 86.2%, 80.7%, 100% and 94.1% respectively. SUV(P) and SUV(M) in PET-CT positive group (5.28±3.24 and 3.56±2.24) was significantly higher than that of PET CT negative group (1.96±0.35 and 1.46±0.44) [p<0.0001 for both]. The size of the primary mass in PET-CT positive group (2.66±1.47) was significantly larger than that in PET-CT negative group (1.52±0.57) (p=0.0002). The nuclear grade and tumor differentiation were not significantly different between two groups. The sensitivity of the FDG PET-CT in detecting primary breast cancer is lower than those of other imaging modalities. The detectability of the FDG PET-CT might be degraded when the tumor is small in size

Cancer screening with FDG-PET

International Nuclear Information System (INIS)

Ide, M.

2006-01-01

Aim: This study is based on medical health check-up and cancer screening on of a medical health club using PET, MRI, spiral CT and other conventional examinations. Methods: Between October 1994 and June 2005, 9357 asymptomatic members of the health club participated in 24772 screening session (5693 men and 3664 women, mean age 52.2±10.4 years). Results: Malignant tumors were discovered in 296 of the 9357 participants (3.16%) and 24772 screening sessions (1.19%). The detection rate of our program is much higher than that of mass screening in Japan. The thyroid, lung, colon and breast cancers were PET positive, but the prostate, renal and bladder cancers were generally PET negative. Conclusion: FDG-PET has the potential to detect a wide variety of cancers at curable stages in asymptomatic individuals. To reduce false-positive and false-negative results of PET examination, there is a need of experienced radiologist and/or oncologists who had training in the wide aspect of FDG-PET. FDG-PET has limitations in the detection of urological cancers, cancers of low cell density, small cancers and hypo metabolic or FDG non-avid cancers. Therefore, conventional examinations and/or PET/CT are also needed for cancer screening in association with FDG-PET

[{sup 18}F]FDG PET/CT outperforms [{sup 18}F]FDG PET/MRI in differentiated thyroid cancer

Energy Technology Data Exchange (ETDEWEB)

Vrachimis, Alexis; Wenning, Christian; Weckesser, Matthias; Stegger, Lars [University Hospital Muenster, Department of Nuclear Medicine, Muenster (Germany); Burg, Matthias Christian; Allkemper, Thomas [University Hospital Muenster, Department of Clinical Radiology, Muenster (Germany); Schaefers, Michael [University Hospital Muenster, Department of Nuclear Medicine, Muenster (Germany); Westfaelische Wilhelms University Muenster, European Institute for Molecular Imaging, Muenster (Germany)

2016-02-15

To evaluate the diagnostic potential of PET/MRI with [{sup 18}F]FDG in comparison to PET/CT in patients with differentiated thyroid cancer suspected or known to have dedifferentiated. The study included 31 thyroidectomized and remnant-ablated patients who underwent a scheduled [{sup 18}F]FDG PET/CT scan and were then enrolled for a PET/MRI scan of the neck and thorax. The datasets (PET/CT, PET/MRI) were rated regarding lesion count, conspicuity, diameter and characterization. Standardized uptake values were determined for all [{sup 18}F]FDG-positive lesions. Histology, cytology, and examinations before and after treatment served as the standards of reference. Of 26 patients with a dedifferentiated tumour burden, 25 were correctly identified by both [{sup 18}F]FDG PET/CT and PET/MRI. Detection rates by PET/CT and PET/MRI were 97 % (113 of 116 lesions) and 85 % (99 of 113 lesions) for malignant lesions, and 100 % (48 of 48 lesions) and 77 % (37 of 48 lesions) for benign lesions, respectively. Lesion conspicuity was higher on PET/CT for both malignant and benign pulmonary lesions and in the overall rating for malignant lesions (p < 0.001). There was a difference between PET/CT and PET/MRI in overall evaluation of malignant lesions (p < 0.01) and detection of pulmonary metastases (p < 0.001). Surgical evaluation revealed three malignant lesions missed by both modalities. PET/MRI additionally failed to detect 14 pulmonary metastases and 11 benign lesions. In patients with thyroid cancer and suspected or known dedifferentiation, [{sup 18}F]FDG PET/MRI was inferior to low-dose [{sup 18}F]FDG PET/CT for the assessment of pulmonary status. However, for the assessment of cervical status, [{sup 18}F]FDG PET/MRI was equal to contrast-enhanced neck [{sup 18}F]FDG PET/CT. Therefore, [{sup 18}F]FDG PET/MRI combined with a low-dose CT scan of the thorax may provide an imaging solution when high-quality imaging is needed and high-energy CT is undesirable or the use of a contrast

78 FR 46813 - Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI

Science.gov (United States)

2013-08-02

...-AA00 Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI AGENCY: Coast Guard, DHS. ACTION.... This temporary safety zone will restrict vessels from a portion of Sturgeon Bay due to a fireworks... hazards associated with the fireworks display. DATES: This rule is effective from 8 p.m. until 10 p.m. on...

Modern imaging methods: positron emission tomography (PET) and positron emission tomography/computed tomography (PET/CT) combination

International Nuclear Information System (INIS)

Votrubova, J.; Belohlavek, O.

2004-01-01

An overview of the title topic is presented. Attention is paid to the technical principles of PET and CT, indications for PET and PET/CT examination, and achievements of the PET Centre of the Na Homolce hospital. (P.A.)

The clinical impact of [18F]FDG PET/CT for the management of recurrent endometrial cancer: correlation with clinical and histological findings

International Nuclear Information System (INIS)

Chung, Hyun Hoon; Kim, Jae Weon; Park, Noh-Hyun; Song, Yong-Sang; Kang, Soon-Beom; Kang, Won Jun; Chung, June-Key

2008-01-01

The purpose of this study was to evaluate the accuracy of integrated positron emission tomography (PET) and computed tomography (CT) for the identification of suspected recurrent endometrial cancer after treatment. Thirty-one women (median age, 53 years) with endometrial cancer treated by primary staging laparotomy who had [ 18 F]fluorodeoxyglucose (FDG) PET/CT performed for suspected recurrence were retrospectively reviewed. The findings of the PET/CT scans were compared, with the histological examination after a surgical biopsy in 20 cases and with clinical follow-up in 11 cases to determine the diagnostic accuracy of PET/CT. Twelve (38.7%) of the 31 patients had a documented recurrence by surgical biopsy or clinical follow-up, and 19 (61.3%) had no evidence of recurrence. Of the 12 patients with recurrent disease, nine (75.0%) women were confirmed to have a recurrence by surgical biopsy. A close correlation was found between the PET/CT and histological or clinical analyses (κ = 0.933, p < 0.001). The overall sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and accuracy of PET/CT were 100, 94.7, 92.3, 100, and 96.8%, respectively. The PET/CT results modified the diagnostic or treatment plan in seven (22.6%) patients, resulting in five (16.1%) patients undergoing previously unplanned therapeutic procedures and eliminating previously planned diagnostic procedures in two (6.5%) patients. Patients with negative PET/CT scans showed significantly better progression-free survival than those with positive scans (p = 0.015). Integrated PET/CT appears to be highly sensitive, specific, and accurate as a post-therapy surveillance modality for endometrial cancer in well-selected patients. The PET/CT might be used to improve patient surveillance and prognosis. (orig.)

PET/CT and radiotherapy

International Nuclear Information System (INIS)

Messa, C.; CNR, Milano; S. Gerardo Hospital, Monza; Di Muzio, N.; Picchio, M.; Bettinardi, V.; Gilardi, M.C.; CNR, Milano; San Raffaele Scientific Institute, Milano; Fazio, F.; CNR, Milano; San Raffaele Scientific Institute, Milano; San Raffaele Scientific Institute, Milano

2006-01-01

This article reviews the state of the art of PET/CT applications in radiotherapy, specifically its use in disease staging, patient selection, treatment planning and treatment evaluation. Diseases for which radiotherapy with radical intent is indicated will be considered, as well as those in which PET/CT may actually change the course of disease. The methodological and technological aspects of PET/CT in radiotherapy are discussed, focusing on the problem of target volume definition with CT and PET functional imaging and the problem of tumor motion with respect to imaging and dose delivery

Pets and the immunocompromised person

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... marrow transplant patients and pets; Chemotherapy patients and pets ... Centers for Disease Control and Prevention website. Healthy pets healthy people. www.cdc.gov/healthypets . Updated July 19, 2016. ...

77 FR 38488 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY

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2012-06-28

... 1625-AA00 Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY... restrict vessels from a portion of the St. Lawrence River during the Alexandria Bay Chamber of Commerce... of proposed rulemaking (NPRM) entitled Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence...

Reliability of semiquantitative 18F-FDG PET parameters derived from simultaneous brain PET/MRI: A feasibility study

International Nuclear Information System (INIS)

Jena, Amarnath; Taneja, Sangeeta; Goel, Reema; Renjen, Pushpendranath; Negi, Pradeep

2014-01-01

Purpose: Simultaneous brain PET/MRI faces an important issue of validation of accurate MRI based attenuation correction (AC) method for precise quantitation of brain PET data unlike in PET/CT systems where the use of standard, validated CT based AC is routinely available. The aim of this study was to investigate the feasibility of evaluation of semiquantitative 18 F-FDG PET parameters derived from simultaneous brain PET/MRI using ultrashort echo time (UTE) sequences for AC and to assess their agreement with those obtained from PET/CT examination. Methods: Sixteen patients (age range 18–73 years; mean age 49.43 (19.3) years; 13 men 3 women) underwent simultaneous brain PET/MRI followed immediately by PET/CT. Quantitative analysis of brain PET images obtained from both studies was undertaken using Scenium v.1 brain analysis software package. Twenty ROIs for various brain regions were system generated and 6 semiquantitative parameters including maximum standardized uptake value (SUV max), SUV mean, minimum SUV (SUV min), minimum standard deviation (SD min), maximum SD (SD max) and SD from mean were calculated for both sets of PET data for each patient. Intra-class correlation coefficients (ICCs) were determined to assess agreement between the various semiquantitative parameters for the two PET data sets. Results: Intra-class co-relation between the two PET data sets for SUV max, SUV mean and SD max was highly significant (p < 0.00) for all the 20 predefined brain regions with ICC > 0.9. SD from mean was also found to be statistically significant for all the predefined brain regions with ICC > 0.8. However, SUV max and SUV mean values obtained from PET/MRI were significantly lower compared to those of PET/CT for all the predefined brain regions. Conclusion: PET quantitation accuracy using the MRI based UTE sequences for AC in simultaneous brain PET/MRI is reliable in a clinical setting, being similar to that obtained using PET/CT

Prospective comparison of whole-body {sup 18}F-FDG PET/CT and MRI of the spine in the diagnosis of haematogenous spondylodiscitis

Energy Technology Data Exchange (ETDEWEB)

Fuster, David; Mayoral, Maria; Manchon, Francisco; Granados, Ulises; Pons, Francesca [Hospital Clinic, Nuclear Medicine Department, Barcelona (Spain); Tomas, Xavier; Cardenal, Carles [Hospital Clinic, Radiology Department, Barcelona (Spain); Soriano, Alex [Hospital Clinic, Infectious Diseases Department, Barcelona (Spain); Monegal, Anna [Hospital Clinic, Rheumatology Department, Barcelona (Spain); Garcia, Sebastia [Hospital Clinic, Orthopedic Surgery and Traumatology Department, Barcelona (Spain)

2014-09-04

To prospectively compare {sup 18}F-FDG PET/CT and MRI in the diagnosis of haematogenous spondylodiscitis The study included 26 patients (12 women, 14 men; mean age 59 ± 17 years) with clinical symptoms of infection of the spine. Patients who had had prior spinal surgery or any type of antibiotic therapy in the previous 3 months were excluded from the study. Whole-body PET/CT 60 min after injection of 4.07 MBq/kg of {sup 18}F-FDG and an MRI scan of the spine was performed in all patients. SUVmax in an area surrounding the lesions with the suspicion of infection as well as a background SUVmean in a preserved area of the spine were calculated for quantification. Infection was diagnosed by microbiological documentation in cultures of image-guided spinal puncture fluid or blood. Infection was excluded if symptoms were absent without antimicrobial therapy during a follow-up of at least 6 months. Spondylodiscitis was confirmed in 18 of the 26 patients. Staphylococcus aureus was found in 8 patients, Mycobacterium tuberculosis in 4, Escherichia coli in 2 and other pathogens in 4. Of the remaining 8 patients, the diagnoses were degenerative spondyloarthropathy in 5 and vertebral fracture in 3. The sensitivity, specificity, and positive and negative predictive value were 83 %, 88 %, 94 % and 70 % for {sup 18}F-FDG PET/CT, and 94 %, 38 %, 77 % and 75 % for MRI, respectively. The accuracies of {sup 18}F-FDG PET/CT and MRI were similar (84 % and 81 %, respectively). The combination of {sup 18}F-FDG PET/CT and MRI detected the infection in 100 % of the patients with spondylodiscitis. {sup 18}F-FDG uptake, quantified in terms of SUVmax corrected by the background SUVmean, was significantly higher in patients with spondylodiscitis than in those without infection (p < 0.001). Due to its high specificity, {sup 18}F-FDG PET/CT should be considered as a first-line imaging procedure in the diagnosis of spondylodiscitis. Quantification of uptake in terms of SUVmax was able to

29 CFR 94.640 - Employee.

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2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Employee. 94.640 Section 94.640 Labor Office of the... § 94.640 Employee. (a) Employee means the employee of a recipient directly engaged in the performance of work under the award, including— (1) All direct charge employees; (2) All indirect charge...

An update on the role of PET/CT and PET/MRI in ovarian cancer

International Nuclear Information System (INIS)

Khiewvan, Benjapa; Torigian, Drew A.; Emamzadehfard, Sahra; Paydary, Koosha; Salavati, Ali; Houshmand, Sina; Werner, Thomas J.; Alavi, Abass

2017-01-01

This review article summarizes the role of PET/CT and PET/MRI in ovarian cancer. With regard to the diagnosis of ovarian cancer, the presence of FDG uptake within the ovary of a postmenopausal woman raises the concern for ovarian cancer. Multiple studies show that FDG PET/CT can detect lymph node and distant metastasis in ovarian cancer with high accuracy and may, therefore, alter the management to obtain better clinical outcomes. Although PET/CT staging is superior for N and M staging of ovarian cancer, its role is limited for T staging. Additionally, FDG PET/CT is of great benefit in evaluating treatment response and has prognostic value in patients with ovarian cancer. FDG PET/CT also has value to detect recurrent disease, particularly in patients with elevated serum CA-125 levels and negative or inconclusive conventional imaging test results. PET/MRI may beneficial for tumor staging because MRI has higher soft tissue contrast and no ionizing radiation exposure compared to CT. Some non-FDG PET radiotracers such as 18 F-fluorothymidine (FLT) or 11 C-methionine (MET) have been studied in preclinical and clinical studies as well and may play a role in the evaluation of patients with ovarian cancer. (orig.)

An update on the role of PET/CT and PET/MRI in ovarian cancer

Energy Technology Data Exchange (ETDEWEB)

Khiewvan, Benjapa [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Mahidol University, Division of Nuclear Medicine, Department of Radiology, Faculty of Medicine Siriraj Hospital, Bangkok (Thailand); Torigian, Drew A.; Emamzadehfard, Sahra; Paydary, Koosha; Salavati, Ali; Houshmand, Sina; Werner, Thomas J.; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States)

2017-06-15

This review article summarizes the role of PET/CT and PET/MRI in ovarian cancer. With regard to the diagnosis of ovarian cancer, the presence of FDG uptake within the ovary of a postmenopausal woman raises the concern for ovarian cancer. Multiple studies show that FDG PET/CT can detect lymph node and distant metastasis in ovarian cancer with high accuracy and may, therefore, alter the management to obtain better clinical outcomes. Although PET/CT staging is superior for N and M staging of ovarian cancer, its role is limited for T staging. Additionally, FDG PET/CT is of great benefit in evaluating treatment response and has prognostic value in patients with ovarian cancer. FDG PET/CT also has value to detect recurrent disease, particularly in patients with elevated serum CA-125 levels and negative or inconclusive conventional imaging test results. PET/MRI may beneficial for tumor staging because MRI has higher soft tissue contrast and no ionizing radiation exposure compared to CT. Some non-FDG PET radiotracers such as {sup 18}F-fluorothymidine (FLT) or {sup 11}C-methionine (MET) have been studied in preclinical and clinical studies as well and may play a role in the evaluation of patients with ovarian cancer. (orig.)

MR-assisted PET motion correction in simultaneous PET/MRI studies of dementia subjects.

Science.gov (United States)

Chen, Kevin T; Salcedo, Stephanie; Chonde, Daniel B; Izquierdo-Garcia, David; Levine, Michael A; Price, Julie C; Dickerson, Bradford C; Catana, Ciprian

2018-03-08

Subject motion in positron emission tomography (PET) studies leads to image blurring and artifacts; simultaneously acquired magnetic resonance imaging (MRI) data provides a means for motion correction (MC) in integrated PET/MRI scanners. To assess the effect of realistic head motion and MR-based MC on static [ 18 F]-fluorodeoxyglucose (FDG) PET images in dementia patients. Observational study. Thirty dementia subjects were recruited. 3T hybrid PET/MR scanner where EPI-based and T 1 -weighted sequences were acquired simultaneously with the PET data. Head motion parameters estimated from high temporal resolution MR volumes were used for PET MC. The MR-based MC method was compared to PET frame-based MC methods in which motion parameters were estimated by coregistering 5-minute frames before and after accounting for the attenuation-emission mismatch. The relative changes in standardized uptake value ratios (SUVRs) between the PET volumes processed with the various MC methods, without MC, and the PET volumes with simulated motion were compared in relevant brain regions. The absolute value of the regional SUVR relative change was assessed with pairwise paired t-tests testing at the P = 0.05 level, comparing the values obtained through different MR-based MC processing methods as well as across different motion groups. The intraregion voxelwise variability of regional SUVRs obtained through different MR-based MC processing methods was also assessed with pairwise paired t-tests testing at the P = 0.05 level. MC had a greater impact on PET data quantification in subjects with larger amplitude motion (higher than 18% in the medial orbitofrontal cortex) and greater changes were generally observed for the MR-based MC method compared to the frame-based methods. Furthermore, a mean relative change of ∼4% was observed after MC even at the group level, suggesting the importance of routinely applying this correction. The intraregion voxelwise variability of regional SUVRs

PET/MRI in cancer patients

DEFF Research Database (Denmark)

Kjær, Andreas; Loft, Annika; Law, Ian

2013-01-01

Combined PET/MRI systems are now commercially available and are expected to change the medical imaging field by providing combined anato-metabolic image information. We believe this will be of particular relevance in imaging of cancer patients. At the Department of Clinical Physiology, Nuclear...... described include brain tumors, pediatric oncology as well as lung, abdominal and pelvic cancer. In general the cases show that PET/MRI performs well in all these types of cancer when compared to PET/CT. However, future large-scale clinical studies are needed to establish when to use PET/MRI. We envision...... that PET/MRI in oncology will prove to become a valuable addition to PET/CT in diagnosing, tailoring and monitoring cancer therapy in selected patient populations....

F-18-FDG-hybrid-camera-PET in patients with postoperative fever

International Nuclear Information System (INIS)

Meller, J.; Lehmann, K.; Siefker, U.; Meyer, I.; Altenvoerde, G.; Becker, W.; Sahlmann, C.O.; Schreiber, K.

2002-01-01

Aim: Evaluation of F-18-FDG-hybrid-camera-PET imaging in patients with undetermined postoperative fever (POF). Methods: Prospective study of 18 patients (9 women, 9 men; age 23-85 years) suffering from POF with 2-fluoro-2'-deoxyglucose (F-18-FDG) using a dual headed coincidence camera (DHCC). Surgery had been performed 5-94 days prior to our investigation. 13 of the 18 patients received antibiotic therapy during the time of evaluation. Ten (55%) had an infectious and eight (45%) a norr infectious cause of fever. Results: Increased F-18-FDG-uptake outside the surgical wound occurred in 13 regions (infection n = 11, malignancy n = 2). The sensitivity of F-18-FDG-hybrid-camera-PET in imaging infection in areas outside the surgical wound was 86% and the specificity 100%, respectively. Antibiotic therapy did not negatively influence the results of F-18-FDG-scanning. Increased F-18-FDG-uptake within the surgical wound was seen in 8 of 18 patients. The sensitivity of F-18-FDG-hybrid-camera-PET in imaging infection within the surgical wound was 100% and the specificty 56%, respectively. The interval between surgery and F-18-FDG-scanning was significantly shorter in patients with false positive results compared with patients showing true negative results (median 34 vs. 54 days; p = 0,038). Conclusion: In POF-Patients, F-18-FDG transaxial tomography performed with a F-18-FDG-hybrid-camera-PET is sensitive in the diagnosis of inflammation and malignant disease within and outside the surgical wound. Because of the accumulation of the tracer both in granulation tissue and infection, the specificity in detecting the focus of fever within the surgical wound is poor. (orig.) [de

Pet ownership and physical health.

Science.gov (United States)

Matchock, Robert L

2015-09-01

Pet ownership and brief human-animal interactions can serve as a form of social support and convey a host of beneficial psychological and physiological health benefits. This article critically examines recent relevant literature on the pet-health connection. Cross-sectional studies indicate correlations between pet ownership and numerous aspects of positive health outcomes, including improvements on cardiovascular measures and decreases in loneliness. Quasi-experimental studies and better controlled experimental studies corroborate these associations and suggest that owning and/or interacting with a pet may be causally related to some positive health outcomes. The value of pet ownership and animal-assisted therapy (AAT), as a nonpharmacological treatment modality, augmentation to traditional treatment, and healthy preventive behavior (in the case of pet ownership), is starting to be realized. However, more investigations that employ randomized controlled trials with larger sample sizes and investigations that more closely examine the underlying mechanism of the pet-health effect, such as oxytocin, are needed.

Evaluation of two methods for using MR information in PET reconstruction

International Nuclear Information System (INIS)

Caldeira, L.; Scheins, J.; Almeida, P.; Herzog, H.

2013-01-01

Using magnetic resonance (MR) information in maximum a posteriori (MAP) algorithms for positron emission tomography (PET) image reconstruction has been investigated in the last years. Recently, three methods to introduce this information have been evaluated and the Bowsher prior was considered the best. Its main advantage is that it does not require image segmentation. Another method that has been widely used for incorporating MR information is using boundaries obtained by segmentation. This method has also shown improvements in image quality. In this paper, two methods for incorporating MR information in PET reconstruction are compared. After a Bayes parameter optimization, the reconstructed images were compared using the mean squared error (MSE) and the coefficient of variation (CV). MSE values are 3% lower in Bowsher than using boundaries. CV values are 10% lower in Bowsher than using boundaries. Both methods performed better than using no prior, that is, maximum likelihood expectation maximization (MLEM) or MAP without anatomic information in terms of MSE and CV. Concluding, incorporating MR information using the Bowsher prior gives better results in terms of MSE and CV than boundaries. MAP algorithms showed again to be effective in noise reduction and convergence, specially when MR information is incorporated. The robustness of the priors in respect to noise and inhomogeneities in the MR image has however still to be performed

40 CFR 94.6 - Regulatory structure.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Regulatory structure. 94.6 Section 94... for Compression-Ignition Marine Engines § 94.6 Regulatory structure. This section provides an overview of the regulatory structure of this part. (a) The regulations of this Part 94 are intended to control...

Comparison of the diagnostic performance of FDG-PET and VBM-MRI in very mild Alzheimer's disease

Energy Technology Data Exchange (ETDEWEB)

Kawachi, Takashi [Division of Neuroimaging Research, HIABCD, Himeji, Hyogo (Japan); Kobe University Graduate School of Medicine, Department of Psychiatry, Kobe, Hyogo (Japan); Ishii, Kazunari; Mori, Tetsuya [Division of Neuroimaging Research, HIABCD, Himeji, Hyogo (Japan); Hyogo Brain and Heart Center, Department of Radiology and Nuclear Medicine, Himeji, Hyogo (Japan); Sakamoto, Setsu; Sasaki, Masahiro [Division of Neuroimaging Research, HIABCD, Himeji, Hyogo (Japan); Yamashita, Fumio; Matsuda, Hiroshi [National Center Hospital for Mental, Nervous and Muscular Disorders, National Center of Neurology and Psychiatry, Department of Radiology, Kodaira, Tokyo (Japan); Mori, Etsuro [Institute for Aging Brain and Cognitive Disorders, Hyogo Brain and Heart Center, Himeji, Hyogo (Japan)

2006-07-15

The aim of this study was to compare the diagnostic performance of{sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and voxel-based morphometry (VBM) on magnetic resonance imaging (MRI) in the same group of patients with very mild Alzheimer's disease (AD). Thirty patients with very mild AD (age 67.0{+-}5.8 years; MMSE score 25.5{+-}1.2, range 24-28), 32 patients with mild AD (age 67.0{+-}4.5 years, MMSE score 22.1{+-}0.8, range 21-23) and 60 age- and sex-matched normal volunteers underwent both FDG-PET and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used to conduct voxel by voxel analysis and Z score mapping. First, the region of interest (ROI) maps of significant reductions in glucose metabolism and grey matter density in the mild AD patients were defined. Secondly, analysis of receiver operating characteristic (ROC) curves for Z scores in the ROI maps discriminating very mild AD patients and normal controls was performed. In mild AD patients, FDG-PET indicated significant reductions in glucose metabolism in the bilateral posterior cingulate gyri and the right parietotemporal area, while VBM analysis showed a significant decrease in grey matter volume density in the bilateral amygdala/hippocampus complex, compared with the normal control group. ROC analysis showed that in very mild AD patients the accuracy of FDG-PET diagnosis was 89% and that of VBM-MRI diagnosis was 83%. The accuracy of the combination of FDG-PET and VBM-MRI diagnosis was 94%. In very mild AD, both FDG-PET and VBM-MRI had high accuracy for diagnosis, but FDG-PET showed slightly higher accuracy than VBM-MRI. Combination of the two techniques will yield a higher diagnostic accuracy in very mild AD by making full use of functional and morphological images. (orig.)

Effect of inherent misalignment and head motion in neurological PET/MR with the Philips Ingenuity TF – phantom and patient study

Energy Technology Data Exchange (ETDEWEB)

Teuho, Jarmo; Johansson, Jarkko; Saunavaara, Virva; Kemppainen, Nina; Teräs, Mika [Turku PET Centre, Turku University Hospital, Turku (Finland)

2014-07-29

The aim of the study was to evaluate the effect of misalignment and head motion on image quantification in PET/MR with a novel brain phantom and a healthy control group. The phantom was imaged at two time points in PET/MR, concurrently with PET and PET/CT. Phantom images were evaluated visually and the relative difference in hemispheric accumulation was calculated. Difference in cortical accumulation in a healthy control group was evaluated from non-attenuation corrected (NAC) and MR attenuation corrected (MRAC) images. Regional ROI mean values from F{sup 18}-FDG ratio images and regional hemispheric asymmetries were calculated. Controls were divided to high and low asymmetry groups. A student’s t-test (p<0.005) for group difference and NAC versus MRAC data was performed. Finally, mean PET-MR registration parameters were measured. Only the first phantom scan exhibited asymmetry in lateral frontal cortex (17%) and temporal cortex (19%). Correcting the misalignment of 2.63mm reduced the asymmetry to less than 5%, to a level seen in PET and PET/CT. A significant asymmetry was found in the temporal and parietal cortex between groups in MRAC data with no significant asymmetry in NAC data. Asymmetries in affected MRAC data in temporal and parietal cortex were 9.4% and 11.7%. NAC data from both groups had asymmetry less than 5% in all regions. Both groups had significant y- and z-translation, while only the asymmetry group had significant z-rotation and x-translation. The shift in x-, y-, or z-direction in both groups was less than 4 mm, with no significant differences. Thus, PET-MRAC misalignment may cause under- and overestimation of attenuation in the lines of response on opposite sides of the cortical regions, resulting to asymmetric difference between the hemispheres. Our findings stress the need for novel QC procedures for PET-MR alignment and suggest confirming the quality of PET-MRAC alignment from PET-NAC images.

Perceptions and opinions of Canadian pet owners about anaesthesia, pain and surgery in small animals.

Science.gov (United States)

Steagall, P V; Monteiro, B P; Ruel, H L M; Beauchamp, G; Luca, G; Berry, J; Little, S; Stiles, E; Hamilton, S; Pang, D

2017-07-01

The aim of this study was to evaluate the perceptions and opinions of Canadian pet owners about anaesthesia, pain and surgery in dogs and cats. Six Canadian veterinary hospitals participated. Each practice received 200 copies of a questionnaire that were distributed to pet owners. Questions regarding the use of analgesics, anaesthesia, surgery and onychectomy (cats) were included. Responses were transformed into ordinal scores and analysed with a Cochran-Mantel-Haenszel test. A total of 849 out of 1200 questionnaires were returned. Owners believed more frequently that analgesics are needed for surgical procedures than for the medical conditions. Owners rated as very important/important: "knowing what to expect during illness/injury/surgery" (99·3%), "being assured that all necessary analgesic drugs/techniques will be used" (98·6%), "being informed about procedures/risk" (98·5%), and having a board-certified anaesthesiologist (90·5%). Most owners agreed/partly agreed that pain impacts quality of life (94·2%), and affects their pet's behaviour (89·5%). Most respondents (69%) were women; they were significantly more concerned than men about anaesthesia, pain, cost and client-communication. Cat owners believed that analgesics were necessary for some procedures/conditions significantly more often than canine-only owners. Pet owners with previous surgery disagreed more frequently that "pain after surgery can be helpful" and that "pain in animals is easy to recognize" than those without previous surgery. Most owners think onychectomy should be banned in cats (56·4%). This study identified important areas of client communication regarding pain and its control in pets. © 2017 British Small Animal Veterinary Association.

MRI-assisted PET motion correction for neurologic studies in an integrated MR-PET scanner.

Science.gov (United States)

Catana, Ciprian; Benner, Thomas; van der Kouwe, Andre; Byars, Larry; Hamm, Michael; Chonde, Daniel B; Michel, Christian J; El Fakhri, Georges; Schmand, Matthias; Sorensen, A Gregory

2011-01-01

Head motion is difficult to avoid in long PET studies, degrading the image quality and offsetting the benefit of using a high-resolution scanner. As a potential solution in an integrated MR-PET scanner, the simultaneously acquired MRI data can be used for motion tracking. In this work, a novel algorithm for data processing and rigid-body motion correction (MC) for the MRI-compatible BrainPET prototype scanner is described, and proof-of-principle phantom and human studies are presented. To account for motion, the PET prompt and random coincidences and sensitivity data for postnormalization were processed in the line-of-response (LOR) space according to the MRI-derived motion estimates. The processing time on the standard BrainPET workstation is approximately 16 s for each motion estimate. After rebinning in the sinogram space, the motion corrected data were summed, and the PET volume was reconstructed using the attenuation and scatter sinograms in the reference position. The accuracy of the MC algorithm was first tested using a Hoffman phantom. Next, human volunteer studies were performed, and motion estimates were obtained using 2 high-temporal-resolution MRI-based motion-tracking techniques. After accounting for the misalignment between the 2 scanners, perfectly coregistered MRI and PET volumes were reproducibly obtained. The MRI output gates inserted into the PET list-mode allow the temporal correlation of the 2 datasets within 0.2 ms. The Hoffman phantom volume reconstructed by processing the PET data in the LOR space was similar to the one obtained by processing the data using the standard methods and applying the MC in the image space, demonstrating the quantitative accuracy of the procedure. In human volunteer studies, motion estimates were obtained from echo planar imaging and cloverleaf navigator sequences every 3 s and 20 ms, respectively. Motion-deblurred PET images, with excellent delineation of specific brain structures, were obtained using these 2 MRI

Staging performance of whole-body DWI, PET/CT and PET/MRI in invasive ductal carcinoma of the breast.

Science.gov (United States)

Catalano, Onofrio Antonio; Daye, Dania; Signore, Alberto; Iannace, Carlo; Vangel, Mark; Luongo, Angelo; Catalano, Marco; Filomena, Mazzeo; Mansi, Luigi; Soricelli, Andrea; Salvatore, Marco; Fuin, Niccolo; Catana, Ciprian; Mahmood, Umar; Rosen, Bruce Robert

2017-07-01

The aim of the present study was to evaluate the performance of whole-body diffusion-weighted imaging (WB-DWI), whole-body positron emission tomography with computed tomography (WB-PET/CT), and whole-body positron emission tomography with magnetic resonance imaging (WB-PET/MRI) in staging patients with untreated invasive ductal carcinoma of the breast. Fifty-one women with newly diagnosed invasive ductal carcinoma of the breast underwent WB-DWI, WB-PET/CT and WB-PET/MRI before treatment. A radiologist and a nuclear medicine physician reviewed in consensus the images from the three modalities and searched for occurrence, number and location of metastases. Final staging, according to each technique, was compared. Pathology and imaging follow-up were used as the reference. WB-DWI, WB-PET/CT and WB-PET/MRI correctly and concordantly staged 33/51 patients: stage IIA in 7 patients, stage IIB in 8 patients, stage IIIC in 4 patients and stage IV in 14 patients. WB-DWI, WB-PET/CT and WB-PET/MRI incorrectly and concordantly staged 1/51 patient as stage IV instead of IIIA. Discordant staging was reported in 17/51 patients. WB-PET/MRI resulted in improved staging when compared to WB-PET/CT (50 correctly staged on WB-PET/MRI vs. 38 correctly staged on WB-PET/CT; McNemar's test; p<0.01). Comparing the performance of WB-PET/MRI and WB-DWI (43 correct) did not reveal a statistically significant difference (McNemar test, p=0.14). WB-PET/MRI is more accurate in the initial staging of breast cancer than WB-DWI and WB-PET/CT, however, the discrepancies between WB-PET/MRI and WB-DWI were not statistically significant. When available, WB-PET/MRI should be considered for staging patient with invasive ductal breast carcinoma.

Pet ownership, dog types and attachment to pets in 9-10 year old children in Liverpool, UK.

Science.gov (United States)

Westgarth, Carri; Boddy, Lynne M; Stratton, Gareth; German, Alexander J; Gaskell, Rosalind M; Coyne, Karen P; Bundred, Peter; McCune, Sandra; Dawson, Susan

2013-05-13

Little is known about ethnic, cultural and socioeconomic differences in childhood ownership and attitudes to pets. The objective of this study was to describe the factors associated with living with different pet types, as well as factors that may influence the intensity of relationship or 'attachment' that children have to their pet. Data were collected using a survey of 1021 9-10 year old primary school children in a deprived area of the city of Liverpool, UK. Dogs were the most common pet owned, most common 'favourite' pet, and species most attached to. Twenty-seven percent of dog-owning children (10% of all children surveyed) reported living with a 'Bull Breed' dog (which includes Pit Bulls and Staffordshire Bull Terriers), and the most popular dog breed owned was the Staffordshire Bull Terrier. Multivariable regression modelling identified a number of variables associated with ownership of different pets and the strength of attachment to the child's favourite pet. Girls were more likely to own most pet types, but were no more or less attached to their favourite pet than boys. Children of white ethnicity were more likely to own dogs, rodents and 'other' pets but were no more or less attached to their pets than children of non-white ethnicity. Single and youngest children were no more or less likely to own pets than those with younger brothers and sisters, but they showed greater attachment to their pets. Children that owned dogs lived in more deprived areas than those without dogs, and deprivation increased with number of dogs owned. 'Pit Bull or cross' and 'Bull Breed' dogs were more likely to be found in more deprived areas than other dog types. Non-whites were also more likely to report owning a 'Pit Bull or cross' than Whites. Gender, ethnicity and socioeconomic status were associated with pet ownership, and sibling status with level of attachment to the pet. These are important to consider when conducting research into the health benefits and risks of the

Potential enterotoxicity and antimicrobial resistance pattern of Aeromonas species isolated from pet turtles and their environment.

Science.gov (United States)

Wimalasena, S H M P; Shin, Gee-Wook; Hossain, Sabrina; Heo, Gang-Joon

2017-05-23

To investigate the potential enterotoxicity and antimicrobial resistance of aeromonads from pet turtles as a risk for human infection, one hundred and two Aeromonas spp. were isolated from the feces, skin and rearing environments of pet turtles and identified by biochemical and gyrB sequence analyses. Aeromonas enteropelogenes was the predominant species among the isolates (52.9%) followed by A. hydrophila (32.4%), A. dharkensis (5.9%), A. veronii (4.9%) and A. caviae (3.9%). Their potential enterotoxicities were evaluated by PCR assays for detecting genes encoding cytotoxic enterotoxin (act) and two cytotonic enterotoxins (alt and ast). 75.8% of A. hydrophila isolates exhibited the act + /alt + /ast + genotype, whereas 94.4% of A. enteropelogenes isolates were determined to be act - /alt - /ast - . In an antimicrobial susceptibility test, most isolates were susceptible to all tested antibiotics except amoxicillin, ampicillin, cephalothin, chloramphenicol and tetracycline. Non-susceptible isolates to penicillins (ampicillin and amoxicillin) and fluoroquinolones (ciprofloxacin and norfloxacin) were frequently observed among the A. enteropelogenes isolates. Few isolates were resistant to imipenem, amikacin, ceftriaxone and cefotaxime. Collectively, these results suggest that pet turtles may pose a public health risk of infection by enterotoxigenic and antimicrobial resistant Aeromonas strains.

40 CFR 94.5 - Reference materials.

Science.gov (United States)

2010-07-01

... for Distillation of Petroleum Products at Atmospheric Pressure 94.108 ASTM D 93-02, Standard Test... Method for API Gravity of Crude Petroleum and Petroleum Products (Hydrometer Method) 94.108 ASTM D 445-01... Viscosity) 94.108 ASTM D 613-01, Standard Test Method for Cetane Number of Diesel Fuel Oil 94.108 ASTM D...

Use of the CT component of PET-CT to improve PET-MR registration: demonstration in soft-tissue sarcoma

International Nuclear Information System (INIS)

Somer, Edward J; Benatar, Nigel A; O'Doherty, Michael J; Smith, Mike A; Marsden, Paul K

2007-01-01

We have investigated improvements to PET-MR image registration offered by PET-CT scanning. Ten subjects with suspected soft-tissue sarcomas were scanned with an in-line PET-CT and a clinical MR scanner. PET to CT, CT to MR and PET to MR image registrations were performed using a rigid-body external marker technique and rigid and non-rigid voxel-similarity algorithms. PET-MR registration was also performed using transformations derived from the registration of CT to MR. The external marker technique gave fiducial registration errors of 2.1 mm, 5.1 mm and 5.3 mm for PET-CT, PET-MR and CT-MR registration. Target registration errors were 3.9 mm, 9.0 mm and 9.3 mm, respectively. Voxel-based algorithms were evaluated by measuring the distance between corresponding fiducials after registration. Registration errors of 6.4 mm, 14.5 mm and 9.5 mm, respectively, for PET-CT, PET-MR and CT-MR were observed for rigid-body registration while non-rigid registration gave errors of 6.8 mm, 16.3 mm and 7.6 mm for the same modality combinations. The application of rigid and non-rigid CT to MR transformations to accompanying PET data gives significantly reduced PET-MR errors of 10.0 mm and 8.5 mm, respectively. Visual comparison by two independent observers confirmed the improvement over direct PET-MR registration. We conclude that PET-MR registration can be more accurately and reliably achieved using the hybrid technique described than through direct rigid-body registration of PET to MR

Pets and Parasites

Science.gov (United States)

... good news is that this rarely happens. Most pet-to-people diseases can be avoided by following a few ... your doctor Can a parasite cause death in people and pets? Can human disease from a parasite be treated ...

PET motion correction in context of integrated PET/MR: Current techniques, limitations, and future projections.

Science.gov (United States)

Gillman, Ashley; Smith, Jye; Thomas, Paul; Rose, Stephen; Dowson, Nicholas

2017-12-01

Patient motion is an important consideration in modern PET image reconstruction. Advances in PET technology mean motion has an increasingly important influence on resulting image quality. Motion-induced artifacts can have adverse effects on clinical outcomes, including missed diagnoses and oversized radiotherapy treatment volumes. This review aims to summarize the wide variety of motion correction techniques available in PET and combined PET/CT and PET/MR, with a focus on the latter. A general framework for the motion correction of PET images is presented, consisting of acquisition, modeling, and correction stages. Methods for measuring, modeling, and correcting motion and associated artifacts, both in literature and commercially available, are presented, and their relative merits are contrasted. Identified limitations of current methods include modeling of aperiodic and/or unpredictable motion, attaining adequate temporal resolution for motion correction in dynamic kinetic modeling acquisitions, and maintaining availability of the MR in PET/MR scans for diagnostic acquisitions. Finally, avenues for future investigation are discussed, with a focus on improvements that could improve PET image quality, and that are practical in the clinical environment. © 2017 American Association of Physicists in Medicine.

PET/MR Imaging in Gynecologic Oncology.

Science.gov (United States)

Ohliger, Michael A; Hope, Thomas A; Chapman, Jocelyn S; Chen, Lee-May; Behr, Spencer C; Poder, Liina

2017-08-01

MR imaging and PET using 2-Deoxy-2-[ 18 F]fluoroglucose (FDG) are both useful in the evaluation of gynecologic malignancies. MR imaging is superior for local staging of disease whereas fludeoxyglucose FDG PET is superior for detecting distant metastases. Integrated PET/MR imaging scanners have great promise for gynecologic malignancies by combining the advantages of each modality into a single scan. This article reviews the technology behind PET/MR imaging acquisitions and technical challenges relevant to imaging the pelvis. A dedicated PET/MR imaging protocol; the roles of PET and MR imaging in cervical, endometrial, and ovarian cancers; and future directions for PET/MR imaging are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

Computer aided diagnosis and localization of lateralized temporal lobe epilepsy using interictal FDG-PET

Directory of Open Access Journals (Sweden)

Wesley Thomas Kerr

2013-04-01

Full Text Available Interictal FDG-PET (iPET is a core tool for localizing the epileptogenic focus, potentially before structural MRI, that does not require rare and transient epileptiform discharges or seizures on EEG. The visual interpretation of iPET is challenging and requires years of epilepsy-specific expertise. We have developed an automated computer-aided diagnostic (CAD tool that has the potential to work both independent of and synergistically with expert analysis. Our tool operates on distributed metabolic changes across the whole brain measured by iPET to both diagnose and lateralize temporal lobe epilepsy. When diagnosing left temporal lobe epilepsy (LTLE or right TLE (RTLE versus non-epileptic seizures (NES, our accuracy in reproducing the results of the gold standard long term video-EEG monitoring was 82% (95% confidence interval [CI] 69-90% or 88% (95% CI 76-94%, respectively. The classifier that both diagnosed and lateralized the disease had overall accuracy of 76% (95% CI 66-84%, where 89% (95% CI 77-96% of patients correctly identified with epilepsy were correctly lateralized. When identifying LTLE, our CAD tool utilized metabolic changes across the entire brain. By contrast, only temporal regions and the right frontal lobe cortex, were needed to identify RTLE accurately, a finding consistent with clinical observations and indicative of a potential pathophysiological difference between RTLE and LTLE. The goal of CADs is to complement—not replace—expert analysis. In our dataset, the accuracy of manual analysis of iPET (~80% was similar to CAD. The square correlation between our CAD tool and manual analysis, however, was only 30%, indicating that our CAD tool does not recreate manual analysis. The addition of clinical information to our CAD, however, did not substantively change performance. These results suggest that automated analysis might provide clinically valuable information to focus treatment more effectively.

MR Imaging-Guided Attenuation Correction of PET Data in PET/MR Imaging.

Science.gov (United States)

Izquierdo-Garcia, David; Catana, Ciprian

2016-04-01

Attenuation correction (AC) is one of the most important challenges in the recently introduced combined PET/magnetic resonance (MR) scanners. PET/MR AC (MR-AC) approaches aim to develop methods that allow accurate estimation of the linear attenuation coefficients of the tissues and other components located in the PET field of view. MR-AC methods can be divided into 3 categories: segmentation, atlas, and PET based. This review provides a comprehensive list of the state-of-the-art MR-AC approaches and their pros and cons. The main sources of artifacts are presented. Finally, this review discusses the current status of MR-AC approaches for clinical applications. Copyright © 2016 Elsevier Inc. All rights reserved.

Role of FDG-PET and PET/CT in the diagnosis and management of vasculitis

Energy Technology Data Exchange (ETDEWEB)

Zerizer, Imene; Tan, Kathryn; Khan, Sameer; Barwick, Tara [Department of Nuclear Medicine, Imperial College Healthcare, Hammersmith Hospital, Du Cane Road, London (United Kingdom); Marzola, Maria Cristina [Department of Nuclear Medicine, PET/CT Centre, Radiology and Medical Physics, ' Santa Maria della Misericordia' Hospital, Rovigo (Italy); Rubello, Domenico [Department of Nuclear Medicine, PET/CT Centre, Radiology and Medical Physics, ' Santa Maria della Misericordia' Hospital, Rovigo (Italy)], E-mail: domenico.rubello@libero.it; Al-Nahhas, Adil [Department of Nuclear Medicine, Imperial College Healthcare, Hammersmith Hospital, Du Cane Road, London (United Kingdom)

2010-03-15

Purpose: to investigate the role of FDG-PET and PET/CT in the evaluation of vasculitis. Materials and methods: a systematic revision of the papers published in PubMed/Medline until December 2009 was done. Results: FDG-PET and PET/CT have been proven to be valuable in the diagnosis of large-vessel vasculitis, especially giant cells arteritis with sensitivity values ranging 77% to 92%, and specificity values ranging 89% to 100%. In particular, FDG-PET/CT has demonstrated the potential to non-invasively diagnose the onset of the vasculitis earlier than traditional anatomical imaging techniques, thus enabling prompt treatment. False positive results mainly occur in the differential diagnosis between vasculitis and atherosclerotic vessels in elderly patients. Another area where FDG-PET/CT is gaining wider acceptance is in monitoring response to therapy; it can reliably detect the earliest changes of disease improvement post-therapy, and persistent activity is an indicator of non-responders to therapy. A few data have been reported about medium/small vessel vasculitis. Discussion: FDG-PET and PET/CT have proven utility: (a) in the initial diagnosis of patients suspected of having vasculitis particularly in those who present with non-specific symptoms; (b) in the identification of areas of increased FDG uptake in which a biopsy should be done for obtaining a diagnosis; (c) in evaluating the extent of the disease; (d) in assessing response to treatment.

Role of FDG-PET and PET/CT in the diagnosis and management of vasculitis

International Nuclear Information System (INIS)

Zerizer, Imene; Tan, Kathryn; Khan, Sameer; Barwick, Tara; Marzola, Maria Cristina; Rubello, Domenico; Al-Nahhas, Adil

2010-01-01

Purpose: to investigate the role of FDG-PET and PET/CT in the evaluation of vasculitis. Materials and methods: a systematic revision of the papers published in PubMed/Medline until December 2009 was done. Results: FDG-PET and PET/CT have been proven to be valuable in the diagnosis of large-vessel vasculitis, especially giant cells arteritis with sensitivity values ranging 77% to 92%, and specificity values ranging 89% to 100%. In particular, FDG-PET/CT has demonstrated the potential to non-invasively diagnose the onset of the vasculitis earlier than traditional anatomical imaging techniques, thus enabling prompt treatment. False positive results mainly occur in the differential diagnosis between vasculitis and atherosclerotic vessels in elderly patients. Another area where FDG-PET/CT is gaining wider acceptance is in monitoring response to therapy; it can reliably detect the earliest changes of disease improvement post-therapy, and persistent activity is an indicator of non-responders to therapy. A few data have been reported about medium/small vessel vasculitis. Discussion: FDG-PET and PET/CT have proven utility: (a) in the initial diagnosis of patients suspected of having vasculitis particularly in those who present with non-specific symptoms; (b) in the identification of areas of increased FDG uptake in which a biopsy should be done for obtaining a diagnosis; (c) in evaluating the extent of the disease; (d) in assessing response to treatment.

AX-PET: A novel PET concept with G-APD readout

CERN Document Server

Heller, M; Casella, C; Chesi, E; De Leo, R; Dissertori, G; Fanti, V; Gillam, J E; Joram, C; Lustermann, W; Nappi, E; Oliver, J F; Pauss, F; Rafecas, M; Rudge, A; Ruotsalainen, U; Schinzel, D; Schneider, T; Seguinot, J; Solevi, P; Stapnes, S; Tuna, U; Weilhammer, P

2012-01-01

The AX-PET collaboration has developed a novel concept for high resolution PET imaging to overcome some of the performance limitations of classical PET cameras, in particular the compromise between spatial resolution and sensitivity introduced by the parallax error. The detector consists of an arrangement of long LYSO scintillating crystals axially oriented around the field of view together with arrays of wave length shifter strips orthogonal to the crystals. This matrix allows a precise 3D measurement of the photon interaction point. This is valid both for photoelectric absorption at 511 key and for Compton scattering down to deposited energies of about 100 keV. Crystals and WLS strips are individually read out using Geiger-mode Avalanche Photo Diodes (G-APDs). The sensitivity of such a detector can be adjusted by changing the number of layers and the resolution is defined by the crystal and strip dimensions. Two AX-PET modules were built and fully characterized in dedicated test set-ups at CERN, with point-...

Impact of the PET/CT in the marshalling of the lung cancer; Impacto del PET/CT en el manejo del cancer de pulmon

Energy Technology Data Exchange (ETDEWEB)

Izquierdo F, M C [Hospital Angeles del las Lomas, Huixquilucan, Estado de Mexico (Mexico); Serna M, J A; Quiroz C, O; Luviano V, C; Alcala G, B [Hospital Angeles del Pedregal, Mexico DF. (Mexico)

2005-07-01

The lung cancer constitutes one of the main morbimortality causes in our environment, being indispensable to carry out a clinical staging with bigger accuracy that allows to define it extension with two objectives: 1. The surgery determination. 2. To predict the prognosis. At the present time it has been possible to combine the metabolic-functional image with the anatomical image creating the PET/CT modality (Positron Emission Tomography/ Computerized Tomography) with that which has improved substantially the accuracy and localization of the lesions with sensitivity of 81%, specificity of 94% and an accuracy diagnoses of 90%. In conclusion the PET/CT image technique has been indispensable in the oncological patient's handling especially in the patient with lung cancer changing the perspective diagnoses as well as the treatment avoiding invasive methods like the mediastinoscopy until the realization of extensive surgeries. The metabolic with the anatomical image fusion it has been able to locate with more accuracy the lesions to distance especially in mediastinum, as well as staging has been achieved accurately in a single exploration to the patient with lung cancer overcoming the rest of the non invasive diagnostic tests especially in the valuation of the metastatic at distance illness, transforming it into an exploration technique with a high effectiveness at an appropriate cost benefit. (Author)

Dynamic comparison of PET imaging performance between state-of-the-art ToF-PET/CT and ToF-PET/MR scanners

International Nuclear Information System (INIS)

Delso, Gaspar; Deller, Tim; Khalighi, Mehdi; Veit-Haibach, Patrick; Schulthess, Gustav von

2014-01-01

The goal of the present work was to determine the potential for dose reduction in a new clinical ToF-PET/MR scanner. This was achieved by means of long dynamic phantom acquisitions designed to provide a fair comparison of image quality and lesion detectability, as a function of activity, between the new PET/MR system and a state-of-the art PET/CT.

Use of PET and PET/CT for Radiation Therapy Planning: IAEA expert report 2006-2007

International Nuclear Information System (INIS)

MacManus, Michael; Nestle, Ursula; Rosenzweig, Kenneth E.; Carrio, Ignasi; Messa, Cristina; Belohlavek, Otakar; Danna, Massimo; Inoue, Tomio; Deniaud-Alexandre, Elizabeth; Schipani, Stefano; Watanabe, Naoyuki; Dondi, Maurizio; Jeremic, Branislav

2009-01-01

Positron Emission Tomography (PET) is a significant advance in cancer imaging with great potential for optimizing radiation therapy (RT) treatment planning and thereby improving outcomes for patients. The use of PET and PET/CT in RT planning was reviewed by an international panel. The International Atomic Energy Agency (IAEA) organized two synchronized and overlapping consultants' meetings with experts from different regions of the world in Vienna in July 2006. Nine experts and three IAEA staff evaluated the available data on the use of PET in RT planning, and considered practical methods for integrating it into routine practice. For RT planning, 18 F fluorodeoxyglucose (FDG) was the most valuable pharmaceutical. Numerous studies supported the routine use of FDG-PET for RT target volume determination in non-small cell lung cancer (NSCLC). There was also evidence for utility of PET in head and neck cancers, lymphoma and in esophageal cancers, with promising preliminary data in many other cancers. The best available approach employs integrated PET/CT images, acquired on a dual scanner in the radiotherapy treatment position after administration of tracer according to a standardized protocol, with careful optimization of images within the RT planning system and carefully considered rules for contouring tumor volumes. PET scans that are not recent or were acquired without proper patient positioning should be repeated for RT planning. PET will play an increasing valuable role in RT planning for a wide range of cancers. When requesting PET scans, physicians should be aware of their potential role in RT planning.

PET/CT with intravenous contrast can be used for PET attenuation correction in cancer patients

International Nuclear Information System (INIS)

Berthelsen, A.K.; Holm, S.; Loft, A.; Klausen, T.L.; Andersen, F.; Hoejgaard, L.

2005-01-01

If the CT scan of a combined PET/CT study is performed as a full diagnostic quality CT scan including intravenous (IV) contrast agent, the quality of the joint PET/CT procedure is improved and a separate diagnostic CT scan can be avoided. CT with IV contrast can be used for PET attenuation correction, but this may result in a bias in the attenuation factors. The clinical significance of this bias has not been established. Our aim was to perform a prospective clinical study where each patient had CT performed with and without IV contrast agent to establish whether PET/CT with IV contrast can be used for PET attenuation without reducing the clinical value of the PET scan. A uniform phantom study was used to document that the PET acquisition itself is not significantly influenced by the presence of IV contrast medium. Then, 19 patients referred to PET/CT with IV contrast underwent CT scans without, and then with contrast agent, followed by an 18 F-fluorodeoxyglucose whole-body PET scan. The CT examinations were performed with identical parameters on a GE Discovery LS scanner. The PET data were reconstructed with attenuation correction based on the two CT data sets. A global comparison of standard uptake value (SUV) was performed, and SUVs in tumour, in non-tumour tissue and in the subclavian vein were calculated. Clinical evaluation of the number and location of lesions on all PET/CT scans was performed twice, blinded and in a different random order, by two independent nuclear medicine specialists. In all patients, the measured global SUV of PET images based on CT with IV contrast agent was higher than the global activity using non-contrast correction. The overall increase in the mean SUV (for two different conversion tables tested) was 4.5±2.3% and 1.6±0.5%, respectively. In 11/19 patients, focal uptake was identified corresponding to malignant tumours. Eight out of 11 tumours showed an increased SUV max (2.9±3.1%) on the PET images reconstructed using IV contrast

Gradient Analysis and Classification of Carolina Bay Vegetation: A Framework for Bay Wetlands Conservation and Restoration

Energy Technology Data Exchange (ETDEWEB)

Diane De Steven,Ph.D.; Maureen Tone,PhD.

1997-10-01

This report address four project objectives: (1) Gradient model of Carolina bay vegetation on the SRS--The authors use ordination analyses to identify environmental and landscape factors that are correlated with vegetation composition. Significant factors can provide a framework for site-based conservation of existing diversity, and they may also be useful site predictors for potential vegetation in bay restorations. (2) Regional analysis of Carolina bay vegetation diversity--They expand the ordination analyses to assess the degree to which SRS bays encompass the range of vegetation diversity found in the regional landscape of South Carolina's western Upper Coastal Plain. Such comparisons can indicate floristic status relative to regional potentials and identify missing species or community elements that might be re-introduced or restored. (3) Classification of vegetation communities in Upper Coastal Plain bays--They use cluster analysis to identify plant community-types at the regional scale, and explore how this classification may be functional with respect to significant environmental and landscape factors. An environmentally-based classification at the whole-bay level can provide a system of templates for managing bays as individual units and for restoring bays to desired plant communities. (4) Qualitative model for bay vegetation dynamics--They analyze present-day vegetation in relation to historic land uses and disturbances. The distinctive history of SRS bays provides the possibility of assessing pathways of post-disturbance succession. They attempt to develop a coarse-scale model of vegetation shifts in response to changing site factors; such qualitative models can provide a basis for suggesting management interventions that may be needed to maintain desired vegetation in protected or restored bays.

Value of new MR techniques in MR-PET; Stellenwert neuer MR-Techniken in der MR-PET

Energy Technology Data Exchange (ETDEWEB)

Attenberger, U.I.; Schoenberg, S.O. [Universitaetsmedizin Mannheim, Medizinische Fakultaet Mannheim der Universitaet Heidelberg, Institut fuer klinische Radiologie und Nuklearmedizin, Mannheim (Germany); Quick, H.H. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institut fuer Medizinische Physik, Erlangen (Germany); Guimaraes, A. [Massachusetts General Hospital, Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown (United States); Catalano, O. [University of Naples Federico II, Naples (Italy); Morelli, J.N. [The Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore (United States)

2013-12-15

The unparalleled soft tissue contrast of magnetic resonance imaging (MRI) and the functional information obtainable with 18-F fluorodeoxyglucose positron emission tomography (FDG-PET) render MR-PET well-suited for oncological and psychiatric imaging. The lack of ionizing radiation with MRI also makes MR-PET a promising modality for oncology patients requiring frequent follow-up and pediatric patients. Lessons learned with PET computed tomography (CT) over the last few years do not directly translate to MR-PET. For example, in PET-CT the Hounsfield units derived from CT are used for attenuation correction (AC). As 511 keV photons emitted in PET examinations are attenuated by the patient's body CT data are converted directly to linear attenuation coefficients (LAC); however, proton density measured by MRI is not directly related to the radiodensity or LACs of biological tissue. Thus, direct conversion to LAC data is not possible making AC more challenging in simultaneous MRI-PET scanning. In addition to these constraints simultaneous MRI-PET acquisitions also improve on some solutions to well-known challenges of hybrid imaging techniques, such as limitations in motion correction. This article reports on initial clinical experiences with simultaneously acquired MRI-PET data, focusing on the potential benefits and limitations of MRI with respect to motion correction as well as metal and attenuation correction artefacts. (orig.) [German] Die klinische Implementierung der neuen Hybridtechnologie MR-Positronenemissionstomographie (MR-PET) bietet durch die Kombination aus hochaufloesender Morphologie, Funktion und Metabolismus bisher ungeahnte diagnostische Moeglichkeiten, die nicht nur fuer die Diagnose und die Verlaufskontrolle onkologischer und psychiatrischer Erkrankungen von hoher Bedeutung sind. Verglichen mit der PET-CT wird dies mit reduzierter Strahlenbelastung fuer den Patienten moeglich, was wiederum insbesondere fuer Patienten in der Tumornachsorge, die

Oncologic PET/CT: current status and controversies

International Nuclear Information System (INIS)

Siegel, B.A.; Dehdashti, F.

2005-01-01

The introduction of integrated PET/CT has dramatically increased the worldwide rate of growth for PET, predominantly for oncologic imaging with the glucose analog 18 F-fluorodeoxyglucose (FDG). A rapidly expanding body of literature demonstrates that the use FDG-PET/CT and the resultant ability to interpret coregistered and fused PET and CT images lead to improved observer confidence and improved diagnostic performance by comparison with PET alone, CT alone, and visually correlated PET and CT. The value of PET/CT is likely to be even greater with new PET radiopharmaceuticals under development, many of which produce PET images with even fewer anatomical landmarks than FDG images. PET/CT is also likely to lead to the resurrection of 18 F-fluoride as a principal agent for radionuclide bone imaging. There are a number of controversies related to PET/CT, including minimum training and experience requirements for interpreting physicians and defining new models for technical and professional reimbursement. (orig.)

Gamma camera based FDG PET in oncology

International Nuclear Information System (INIS)

Park, C. H.

2002-01-01

Positron Emission Tomography(PET) was introduced as a research tool in the 1970s and it took about 20 years before PET became an useful clinical imaging modality. In the USA, insurance coverage for PET procedures in the 1990s was the turning point, I believe, for this progress. Initially PET was used in neurology but recently more than 80% of PET procedures are in oncological applications. I firmly believe, in the 21st century, one can not manage cancer patients properly without PET and PET is very important medical imaging modality in basic and clinical sciences. PET is grouped into 2 categories; conventional (c) and gamma camera based ( CB ) PET. CB PET is more readily available utilizing dual-head gamma cameras and commercially available FDG to many medical centers at low cost to patients. In fact there are more CB PET in operation than cPET in the USA. CB PET is inferior to cPET in its performance but clinical studies in oncology is feasible without expensive infrastructures such as staffing, rooms and equipments. At Ajou university Hospital, CBPET was installed in late 1997 for the first time in Korea as well as in Asia and the system has been used successfully and effectively in oncological applications. Our was the fourth PET operation in Korea and I believe this may have been instrumental for other institutions got interested in clinical PET. The following is a brief description of our clinical experience of FDG CBPET in oncology

Extended suicide with a pet.

Science.gov (United States)

Cooke, Brian K

2013-01-01

The combination of the killing of a pet and a suicide is a perplexing scenario that is largely unexplored in the literature. Many forensic psychiatrists and psychologists may be unaccustomed to considering the significance of the killing of a pet. The subject is important, however, because many people regard their pets as members of their family. A case is presented of a woman who killed her pet dog and herself by carbon monoxide poisoning. The purpose of this article is to provide an initial exploration of the topic of extended suicide with a pet. Forensic mental health evaluations may have a role in understanding the etiology of this event and in opining as to the culpability of individuals who attempt to or successfully kill a pet and then commit suicide. Because the scientific literature is lacking, there is a need to understand this act from a variety of perspectives. First, a social and anthropological perspective will be presented that summarizes the history of the practice of killing of one's pet, with a focus on the ancient Egyptians. A clinical context will examine what relationship animals have to mental illness. A vast body of existing scientific data showing the relevance of human attachment to pets suggests that conclusions from the phenomena of homicide-suicide and filicide-suicide are applicable to extended suicide with a pet. Finally, recommendations will be proposed for both clinical and forensic psychiatrists faced with similar cases.

Cyclotron/PET project in Uruguay

International Nuclear Information System (INIS)

Engler, H.

2006-01-01

The Positron Computed Tomography (PET) is a tri dimensional image technique which shows biochemical information. PET is used in neurology and cardiology diseases. The National Center Cyclotron PET has been found to research, development and health science applications.

Simultaneous acquisition of multislice PET and MR images: initial results with a MR-compatible PET scanner.

Science.gov (United States)

Catana, Ciprian; Wu, Yibao; Judenhofer, Martin S; Qi, Jinyi; Pichler, Bernd J; Cherry, Simon R

2006-12-01

PET and MRI are powerful imaging techniques that are largely complementary in the information they provide. We have designed and built a MR-compatible PET scanner based on avalanche photodiode technology that allows simultaneous acquisition of PET and MR images in small animals. The PET scanner insert uses magnetic field-insensitive, position-sensitive avalanche photodiode (PSAPD) detectors coupled, via short lengths of optical fibers, to arrays of lutetium oxyorthosilicate (LSO) scintillator crystals. The optical fibers are used to minimize electromagnetic interference between the radiofrequency and gradient coils and the PET detector system. The PET detector module components and the complete PET insert assembly are described. PET data were acquired with and without MR sequences running, and detector flood histograms were compared with the ones generated from the data acquired outside the magnet. A uniform MR phantom was also imaged to assess the effect of the PET detector on the MR data acquisition. Simultaneous PET and MRI studies of a mouse were performed ex vivo. PSAPDs can be successfully used to read out large numbers of scintillator crystals coupled through optical fibers with acceptable performance in terms of energy and timing resolution and crystal identification. The PSAPD-LSO detector performs well in the 7-T magnet, and no visible artifacts are detected in the MR images using standard pulse sequences. The first images from the complete system have been successfully acquired and reconstructed, demonstrating that simultaneous PET and MRI studies are feasible and opening up interesting possibilities for dual-modality molecular imaging studies.

Simulation study comparing the helmet-chin PET with a cylindrical PET of the same number of detectors

Science.gov (United States)

Ahmed, Abdella M.; Tashima, Hideaki; Yoshida, Eiji; Nishikido, Fumihiko; Yamaya, Taiga

2017-06-01

There is a growing interest in developing brain PET scanners with high sensitivity and high spatial resolution for early diagnosis of neurodegenerative diseases and studies of brain functions. Sensitivity of the PET scanner can be improved by increasing the solid angle. However, conventional PET scanners are designed based on a cylindrical geometry, which may not be the most efficient design for brain imaging in terms of the balance between sensitivity and cost. We proposed a dedicated brain PET scanner based on a hemispheric shape detector and a chin detector (referred to as the helmet-chin PET), which is designed to maximize the solid angle by increasing the number of lines-of-response in the hemisphere. The parallax error, which PET scanners with a large solid angle tend to have, can be suppressed by the use of depth-of-interaction detectors. In this study, we carry out a realistic evaluation of the helmet-chin PET using Monte Carlo simulation based on the 4-layer GSO detector which consists of a 16  ×  16  ×  4 array of crystals with dimensions of 2.8  ×  2.8  ×  7.5 mm3. The purpose of this simulation is to show the gain in imaging performance of the helmet-chin PET compared with the cylindrical PET using the same number of detectors in each configuration. The sensitivity of the helmet-chin PET evaluated with a cylindrical phantom has a significant increase, especially at the top of the (field-of-view) FOV. The peak-NECR of the helmet-chin PET is 1.4 times higher compared to the cylindrical PET. The helmet-chin PET provides relatively low noise images throughout the FOV compared to the cylindrical PET which exhibits enhanced noise at the peripheral regions. The results show the helmet-chin PET can significantly improve the sensitivity and reduce the noise in the reconstructed images.

Effect of MR contrast agents on quantitative accuracy of PET in combined whole-body PET/MR imaging

Energy Technology Data Exchange (ETDEWEB)

Lois, Cristina [University of Santiago de Compostela, Department of Particle Physics, Santiago de Compostela (Spain); Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela (Spain); Imaging Science Institute, Tuebingen (Germany); Bezrukov, Ilja [Eberhard Karls University, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens Foundation, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Max Plank Institute for Intelligent Systems, Department of Empirical Inference, Tuebingen (Germany); Schmidt, Holger [Eberhard Karls University, Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens Foundation, Department of Preclinical Imaging and Radiopharmacy, Tuebingen (Germany); Eberhard Karls University, Diagnostic and Interventional Radiology, Department of Radiology, Tuebingen (Germany); Schwenzer, Nina; Werner, Matthias K. [Eberhard Karls University, Diagnostic and Interventional Radiology, Department of Radiology, Tuebingen (Germany); Kupferschlaeger, Juergen [Eberhard Karls University, Nuclear Medicine, Department of Radiology, Tuebingen (Germany); Beyer, Thomas [Imaging Science Institute, Tuebingen (Germany); cmi-experts GmbH, Zuerich (Switzerland)

2012-11-15

Clinical PET/MR acquisition protocols entail the use of MR contrast agents (MRCA) that could potentially affect PET quantification following MR-based attenuation correction (AC). We assessed the effect of oral and intravenous (IV) MRCA on PET quantification in PET/MR imaging. We employed two MRCA: Lumirem {sup registered} (oral) and Gadovist {sup registered} (IV). First, we determined their reference PET attenuation values using a PET transmission scan (ECAT-EXACT HR+, Siemens) and a CT scan (PET/CT Biograph 16 HI-REZ, Siemens). Second, we evaluated the attenuation of PET signals in the presence of MRCA. Phantoms were filled with clinically relevant concentrations of MRCA in a background of water and {sup 18}F-fluoride, and imaged using a PET/CT scanner (Biograph 16 HI-REZ, Siemens) and a PET/MR scanner (Biograph mMR, Siemens). Third, we investigated the effect of clinically relevant volumes of MRCA on MR-based AC using human pilot data: a patient study employing Gadovist {sup registered} (IV) and a volunteer study employing two different oral MRCA (Lumirem {sup registered} and pineapple juice). MR-based attenuation maps were calculated following Dixon-based fat-water segmentation and an external atlas-based and pattern recognition (AT and PR) algorithm. IV and oral MRCA in clinically relevant concentrations were found to have PET attenuation values similar to those of water. The phantom experiments showed that under clinical conditions IV and oral MRCA did not yield additional attenuation of PET emission signals. Patient scans showed that PET attenuation maps are not biased after the administration of IV MRCA but may be biased, however, after ingestion of iron oxide-based oral MRCA when segmentation-based AC algorithms are used. Alternative AC algorithms, such as AT and PR, or alternative oral contrast agents, such as pineapple juice, can yield unbiased attenuation maps. In clinical PET/MR scenarios MRCA are not expected to lead to markedly increased attenuation

Simultaneous PET and MR imaging

International Nuclear Information System (INIS)

Yiping Shao; Cherry, Simon R.; Meadors, Ken; Siegel, Stefan; Silverman, Robert W.; Farahani, Keyvan; Marsden, Paul K.

1997-01-01

We have developed a prototype PET detector which is compatible with a clinical MRI system to provide simultaneous PET and MR imaging. This single-slice PET system consists of 48 2x2x10mm 3 LSO crystals in a 38 mm diameter ring configuration that can be placed inside the receiver coil of the MRI system, coupled to three multi-channel photomultipliers housed outside the main magnetic field via 4 m long and 2 mm diameter optical fibres. The PET system exhibits 2 mm spatial resolution, 41% energy resolution at 511 keV and 20 ns timing resolution. Simultaneous PET and MR phantom images were successfully acquired. (author)

Associations of Pet Ownership with Wheezing and Lung Function in Childhood: Findings from a UK Birth Cohort.

Science.gov (United States)

Collin, Simon M; Granell, Raquel; Westgarth, Carri; Murray, Jane; Paul, Elizabeth S; Sterne, Jonathan A C; Henderson, A John

2015-01-01

Asthma is a heterogeneous condition and differential effects of pet ownership on non-atopic versus atopic asthma have been reported. The aim of this study was to investigate whether pet ownership during pregnancy and early childhood was associated with wheezing from birth to age 7 years and with lung function at age 8 years in a UK population-based birth cohort. Data from the Avon Longitudinal Study of Parents and Children (ALSPAC) were used to investigate associations of pet ownership at six time-points from pregnancy to age 7 years with concurrent episodes of wheezing, wheezing trajectories (phenotypes) and lung function at age 8 years using logistic regression models adjusted for child's sex, maternal history of asthma/atopy, maternal smoking during pregnancy, and family adversity. 4,706 children had complete data on pet ownership and wheezing. From birth to age 7 years, cat ownership was associated with an overall 6% lower odds of wheezing (OR=0.94 (0.89-0.99)). Rabbit and rodent ownership was associated with 21% (OR=1.21 (1.12-1.31)) and 11% (OR=1.11 (1.02-1.21)) higher odds of wheezing, respectively, with strongest effects evident during infancy. Rabbit and rodent ownership was positively associated with a 'persistent wheeze' phenotype. Pet ownership was not associated with lung function at age 8 years, with the exception of positive associations of rodent and bird ownership with better lung function. Cat ownership was associated with reduced risk, and rabbit and rodent ownership with increased risk, of wheezing during childhood. The mechanisms behind these differential effects warrant further investigation.

Additive value of amyloid-PET in routine cases of clinical dementia work-up after FDG-PET