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Sample records for f-18 fdg brain

  1. Spectrum of brain abnormalities detected on whole body F-18 FDG PET/CT in patients undergoing evaluation for non-CNS malignancies

    PubMed Central

    Tripathi, Madhavi; Jaimini, Abhinav; D’Souza, Maria M; Sharma, Rajnish; Jain, Jyotika; Garg, Gunjan; Singh, Dinesh; Kumar, Nitin; Mishra, Anil K; Grover, Rajesh K; Mondal, Anupam

    2011-01-01

    We present the pattern of metabolic brain abnormalities detected in patients undergoing whole body (WB) F-18 flurodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) examination for non-central nervous system (CNS) malignancies. Knowledge of the PET/CT appearance of various intracranial metabolic abnormalities enables correct interpretation of PET scans in oncological patients where differentiation of metastasis from benign intracranial pathologies is important and improves specificity of the PET study. A complete clinical history and correlation with CT and MRI greatly helps in arriving at a correct imaging diagnosis. PMID:22174526

  2. F-18 FDG PET/CT Findings of a Patient with Takayasu Arteritis Before and After Therapy

    PubMed Central

    Sağer, Sait; Yılmaz, Sabire; Özhan, Meftune; Halaç, Metin; Ergül, Nurhan; Çiftci, Hediye; Çermik, T. Fikret

    2012-01-01

    Vasculitis is defined as inflammation and necrosis with leukocytic infiltration of the blood vessel wall. Takayasu arteritis is a chronic inflammatory arteritis that primarily involves the aorta and its main branches. A 64-year-old female patient with a 2-month history of fever of unknown origin was presented to our clinic for F-18 FDG PET/CT imaging. Baseline PET/CT images demonstrated intense F-18 FDG uptake in the aorta, bilateral subclavian and brachiocephalic arteries consistent with Takayasu arteritis. After 2 months of immunosuppressive therapy, she was asymptomatic and follow-up FDG PET/CT scan showed almost complete disappearance of large vessels’ F-18 FDG uptake. FDG PET/CT is a sensitive technique for assessing presence of large-vessel vasculitis such as Takayasu arteritis, extent of large-vessel inflammation and disease activity after therapy. Conflict of interest:None declared. PMID:23486556

  3. Differential diagnosis of neurodegenerative dementias using metabolic phenotypes on F-18 FDG PET/CT.

    PubMed

    Tripathi, Madhavi; Tripathi, Manjari; Damle, Nishikant; Kushwaha, Suman; Jaimini, Abhinav; D'Souza, Maria M; Sharma, Rajnish; Saw, Sanjiv; Mondal, Anupam

    2014-02-01

    Positron emission tomography (PET) imaging with F-18 fluorodeoxyglucose (FDG) can be used as a downstream marker of neuronal injury, a hallmark of neurodegenerative dementias. Characteristic patterns of regional glucose metabolism have been used to classify the dementia subtypes, namely Alzheimer's dementia (AD), frontotemporal dementia (FTD), diffuse Lewy body (DLBD) and vascular dementia (VD). We undertook this study to assess the utility of FDG-PET in the differential diagnosis of dementia subtypes. One hundred and twenty-five patients diagnosed with dementia were referred from cognitive disorders and memory clinics of speciality neurology centres for the FDG-PET study. Imaging-based diagnosis of dementia type was established in 101 patients by visual assessment of individual scans by a PET physician blinded to the clinical diagnosis. The results were compared with an 18-month follow-up clinical assessment made by the specialist neurologist. Concordance of visual evaluation of FDG-PET scans with clinical diagnosis of the dementia type was achieved in 90% of patients scanned. This concordance was 93.4% for AD, 88.8% for FTD, 66.6% for DLBD and 92.3% for the other dementia syndromes. FDG-PET performed after the initial work-up of dementias is useful for supporting the clinical diagnosis of dementia subtype. PMID:24571830

  4. F18-FDG-PET for recurrent differentiated thyroid cancer: a systematic meta-analysis

    PubMed Central

    Haslerud, Torjan; Brauckhoff, Katrin; Reisæter, Lars; Küfner Lein, Regina; Heinecke, Achim; Varhaug, Jan Erik

    2015-01-01

    Background Positron emission tomography (PET) with fluor-18-deoxy-glucose (FDG) is widely used for diagnosing recurrent or metastatic disease in patients with differentiated thyroid cancer (DTC). Purpose To assess the diagnostic accuracy of FDG-PET for DTC in patients after ablative therapy. Material and Methods A systematic search was conducted in Medline/PubMed, EMBASE, Cochrane Library, Web of Science, and Open Grey looking for all English-language original articles on the performance of FDG-PET in series of at least 20 patients with DTC having undergone ablative therapy including total thyroidectomy. Diagnostic performance measures were pooled using Reitsma’s bivariate model. Results Thirty-four publications between 1996 and 2014 met the inclusion criteria. Pooled sensitivity and specificity were 79.4% (95% confidence interval [CI], 73.9–84.1) and 79.4% (95% CI, 71.2–85.4), respectively, with an area under the curve of 0.858. Conclusion F18-FDG-PET is a useful method for detecting recurrent DTC in patients having undergone ablative therapy. PMID:26163534

  5. [F-18] FDG-PET/CT parameters as predictors of outcome in inoperable NSCLC patients

    PubMed Central

    Nappi, Antonio; Gallicchio, Rosj; Simeon, Vittorio; Nardelli, Anna; Pelagalli, Alessandra; Zupa, Angela; Vita, Giulia; Venetucci, Angela; Di Cosola, Michele; Barbato, Francesco; Storto, Giovanni

    2015-01-01

    Background We evaluated the prognostic significance of standardized uptake value (SUVmax), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) in [F-18] FDG PET/CT findings in patients with inoperable non-small-cell lung cancer (NSCLC). Patients and methods. One hundred and three patients (mean age, 65.6 ± 16 years) underwent [F-18] FDG PET/CT before the chemotherapy. The SUVmax value, the MTV (cm3; 42% threshold) and the TLG (g) were registered. The patients were followed up to 18 months thereafter (range 12–55 months). Failure to respond without progression, progression and/or disease-related death constituted surrogate end-points. The optimal SUVmax, MTV and TLG cut-off to predict the patients’ outcome were estimated. PET/CT results were then related to disease outcome (progression free survival; PFS). Results The Kaplan-Meier survival analysis for SUVmax showed a significant shorter PFS in patients presenting with lower values as compared to those with higher (p < 0.05, log-rank test). MTV and TLG were not suitable for predicting PFS apart from the subset of patients with mediastinal nodal involvement. Conclusions Despite the availability of new tools for the quantitative assessment of disease activity on PET/CT, the SUVmax rather than MTV and TLG remains the only predictor for PFS in NSCLC patients. MTV holds a value only when concomitant nodal involvement occurs. PMID:26834517

  6. Comparison of thallium 201 (TL) SPECT and F-18 fluoro-deoxyglucose (FDG) PET in the evaluation of MRI lesions in patients with gliomas after therapy

    SciTech Connect

    Wong, F.C.L.; Garcia, J.R.; Yung, W.K.A.

    1994-05-01

    Although both Tl-201 SPECT and F-18 FDG PET are helpful for the detection of recurrent gliomas, there is DO comparative study of these techniques for the same patient group. This study is performed to compare the efficacy of TL SPECT and FDG PET in differentiating recurrent glioma from post-treatment necrosis. Twenty patients (16M/4 F) treated for gliomas (surgery, radiation and/or chemotherapy) with 24 instructive MRI enhancing lesions underwent TL-201 SPECT and F-18 FDG PET within 1 week. The lesions were graded 0 to 4 (by consensus of three nuclear radiologists) with increasing confidence for recurrent tumors. Semiquantitative evaluations include lesion/scalp TL-201 ratios (L/S TL) and lesion/cortex F-18 FDG (L/C FDG) standard uptake value ratios. With clinical follow-up (12/24) and histopathologic confirmation (12/24), sensitivity and specificity for each grade were used to construct the receiver-operator-characteristic (ROC) curve for comparison. Recurrent gliomas were confirmed in 12/24 lesions (9/12 by pathology; 3/12 by follow-up). Post-treatment necrosis was confirmed in 12/24 lesions (9/12 by follow-up; 3/12 by pathology). The L/S TL ratios were [1.99{plus_minus}0.77] for gliomas and [1.14{plus_minus}0.22] for necrosis; the L/C FDG ratios were 0.86{plus_minus}0.43 for gliomas and 0.43{plus_minus}0.15 for necrosis. Although none of the semiquantitative measurements from TL SPECT and FDG PET could completely distinguish gliomas from post-treatment necrosis, FDG PET was superior to TL SPECT on the ROC curves. While TL-201 SPECT and F-18 FDG PET provide different and probably complementary metabolic measurements of brain lesions, this preliminary work suggests FDG PET is a better tool to evaluate enhancing MRI lesions in patients with treated gliomas. Further confirmation will require studies of more patients.

  7. Regional brain distribution of 2-deoxy-2-[F-18]Fluoro-D-talose: A new PET tracer for measurement of galactokinase activity

    SciTech Connect

    Haradahira, T.; Inoue, O.; Suzuki, K.

    1994-05-01

    We have recently developed a 2-deoxy-2-[F-18]fluoro-D-talose (2-[F-18]FDTal) as a new PET tracer for measurements of galactokinase activities in tissues. The rational of 2-[F-18]FDTal as a PET tracer is based on the metabolic trapping by a formation of 2-[F-18]FDTal-1-phosphate by galactokinase. In this study, we have examined the regional brain distribution of 2-[F-18]FDTal in monkey by PET, and compared it with those of 2-deoxy-2-[F-18]fluoro-D-glucose (2-[F-18]FDG) and 2-deoxy-2-[F-18]fluoro-D-galactose (2-[F-18]FDTal), PET tracers for D-glucose and D-galactose metabolisms, respectively. The F-18 sugars used for the PET studies were prepared through nucleophilic fluorinations of the corresponding triflates with [F-18]fluoride. PET imaging obtained by i.v. injection of 2-[F-18]FDTal in rhesus monkey showed very high accumulation of the radioactivity into an occipital cortex region. This regional distribution was very similar to that of 2-[F-18]FDGal, but was quite different with that of 2-[F-18]FDG. In PET data analyses, washout of the radioactivity from the occipital cortex (30% loss of the initial activity) was observed in an early period ({<=}5 min) after injection of 2-[F-18]FDTal, in contrast with the continuous increase of the radioactivity in the same region after injection of 2-[F-18]FDGal. This data indicates a smaller phosphorylation rate constant (K3) of 2-[F-18]FDTal by brain galactokinase than that of 2-[F-18]FDGal. 2-[F-18]FDGal has been reported to be partly metabolized into an UDP-2-[F-18]FDGal via 2-CF-18]FDGal-l-phosphate in animal brains. Therefore 2-[F-18]FDTal offers an advantage over 2-[F-18]FDGal in undergoing its simple metabolism which enables us to make a simple kinetic model for PET imaging. We conclude that 2-[F-18]FDTal may be a new PET tracer to give a characteristic regional brain distribution which reflect the regional galactokinase activity.

  8. Very low-dose adult whole-body tumor imaging with F-18 FDG PET/CT

    NASA Astrophysics Data System (ADS)

    Krol, Andrzej; Naveed, Muhammad; McGrath, Mary; Lisi, Michele; Lavalley, Cathy; Feiglin, David

    2015-03-01

    The aim of this study was to evaluate if effective radiation dose due to PET component in adult whole-body tumor imaging with time-of-flight F-18 FDG PET/CT could be significantly reduced. We retrospectively analyzed data for 10 patients with the body mass index ranging from 25 to 50. We simulated F-18 FDG dose reduction to 25% of the ACR recommended dose via reconstruction of simulated shorter acquisition time per bed position scans from the acquired list data. F-18 FDG whole-body scans were reconstructed using time-of-flight OSEM algorithm and advanced system modeling. Two groups of images were obtained: group A with a standard dose of F-18 FDG and standard reconstruction parameters and group B with simulated 25% dose and modified reconstruction parameters, respectively. Three nuclear medicine physicians blinded to the simulated activity independently reviewed the images and compared diagnostic quality of images. Based on the input from the physicians, we selected optimal modified reconstruction parameters for group B. In so obtained images, all the lesions observed in the group A were visible in the group B. The tumor SUV values were different in the group A, as compared to group B, respectively. However, no significant differences were reported in the final interpretation of the images from A and B groups. In conclusion, for a small number of patients, we have demonstrated that F-18 FDG dose reduction to 25% of the ACR recommended dose, accompanied by appropriate modification of the reconstruction parameters provided adequate diagnostic quality of PET images acquired on time-of-flight PET/CT.

  9. MO-G-17A-07: Improved Image Quality in Brain F-18 FDG PET Using Penalized-Likelihood Image Reconstruction Via a Generalized Preconditioned Alternating Projection Algorithm: The First Patient Results

    SciTech Connect

    Schmidtlein, CR; Beattie, B; Humm, J; Li, S; Wu, Z; Xu, Y; Zhang, J; Shen, L; Vogelsang, L; Feiglin, D; Krol, A

    2014-06-15

    Purpose: To investigate the performance of a new penalized-likelihood PET image reconstruction algorithm using the 1{sub 1}-norm total-variation (TV) sum of the 1st through 4th-order gradients as the penalty. Simulated and brain patient data sets were analyzed. Methods: This work represents an extension of the preconditioned alternating projection algorithm (PAPA) for emission-computed tomography. In this new generalized algorithm (GPAPA), the penalty term is expanded to allow multiple components, in this case the sum of the 1st to 4th order gradients, to reduce artificial piece-wise constant regions (“staircase” artifacts typical for TV) seen in PAPA images penalized with only the 1st order gradient. Simulated data were used to test for “staircase” artifacts and to optimize the penalty hyper-parameter in the root-mean-squared error (RMSE) sense. Patient FDG brain scans were acquired on a GE D690 PET/CT (370 MBq at 1-hour post-injection for 10 minutes) in time-of-flight mode and in all cases were reconstructed using resolution recovery projectors. GPAPA images were compared PAPA and RMSE-optimally filtered OSEM (fully converged) in simulations and to clinical OSEM reconstructions (3 iterations, 32 subsets) with 2.6 mm XYGaussian and standard 3-point axial smoothing post-filters. Results: The results from the simulated data show a significant reduction in the 'staircase' artifact for GPAPA compared to PAPA and lower RMSE (up to 35%) compared to optimally filtered OSEM. A simple power-law relationship between the RMSE-optimal hyper-parameters and the noise equivalent counts (NEC) per voxel is revealed. Qualitatively, the patient images appear much sharper and with less noise than standard clinical images. The convergence rate is similar to OSEM. Conclusions: GPAPA reconstructions using the 1{sub 1}-norm total-variation sum of the 1st through 4th-order gradients as the penalty show great promise for the improvement of image quality over that currently achieved

  10. Radiation assessment to paediatric with F-18-FDG undergo whole-body PET/CT examination

    NASA Astrophysics Data System (ADS)

    Dhalisa, H.; Mohamad, A. S.; Rafidah, Z.

    2016-01-01

    This study was carried out on wholebody radiation dose assessment to paediatrics patient who undergo PET/CT scanner at Institut Kanser Negara. Consist of 68 patients with varies of malignancies and epilepsy disease case covering age between 2 years to 12 years old. This is a retrospective study from 2010-2014. The use of PET/CT scanner as an advanced tool has been proven to give an extra radiation dose to the patient. It is because of the radiation exposure from the combination of both CT and PET scans rather than a single CT or PET scan. Furthermore, a study on radiation dose to paediatric patient undergoing PET/CT is rare in Malaysia. So, the aim of this study is to estimate the wholebody effective dose to paediatric patient in Malaysia. Effective dose from PET scan was calculated based on the activity of F18 FDG and dose coefficient reported in International Commission on Radiological Protection (ICRP) Publication 106. Effective dose from CT was determined using k coefficient as reported in ICRP publication 102 and Dose Length Product (DLP) value. The average effective dose from PET and CT were found to be 7.05mSv and 5.77mSv respectively. The mean wholebody effective dose received by a patient with combined PETCT examination was 12.78mSv. These results could be used as reference for dosimetry of a patient undergoing PETCT examination in Malaysia.

  11. Neural responses of rats in the forced swimming test: [F-18]FDG micro PET study.

    PubMed

    Jang, Dong-Pyo; Lee, So-Hee; Lee, Sang-Yoon; Park, Chan-Woong; Cho, Zang-Hee; Kim, Young-Bo

    2009-10-12

    The forced swimming test (FST) is a widely used tool in the assessment of behavioral despair and prediction of response to antidepressants. However, the neural mechanisms underlying behavioral changes between pretest and test sessions of the FST remain unclear. In this study, we investigated changes in rat brain activity during the FST using [F-18]Fluorodeoxyglucose micro PET. In both pretest and test sessions, the activity of the cerebellum and striatum increased, whereas significant deactivation was observed in the hippocampus, inferior colliculus, orbital cortex, and insula. The periaqueductal gray (PAG) region activated markedly in the pretest session, but did not activate in the test session. There was a significant increase in immobility and a decrease in climbing during the behavioral analysis test session. These results suggest that the PAG region may play an important role in the modulation of FST coping strategies subsequent to failure of the escape response during the pretest session.

  12. Is there any complimentary role of F-18 NaF PET/CT in detecting of osseous involvement of multiple myeloma? A comparative study for F-18 FDG PET/CT and F-18 FDG NaF PET/CT.

    PubMed

    Ak, İlknur; Onner, Hasan; Akay, Olga Meltem

    2015-09-01

    Multiple myeloma (MM) is a disease characterized by a monoclonal plasma cell population in the bone marrow whereby osseous involvement is a predominant feature. The aim of this prospective study was to investigate the combined use of F-18 FDG and F-18 NaF PET/CT in the skeletal assessment of patients with MM and to compare the efficacy of these two PET tracers regarding detection of myeloma-indicative osseous lesions. A total of 26 patients (14 females and 12 males, mean age 61.8 ± 1.8 years (range 40-81 years)) with MM diagnosed according to standard criteria. All patients underwent both F-18 FDG PET/CT and F-18 NaF PET/CT scans within 1 week after the completion of the usual staging workup for MM. In total, approximately 128 focal F-18 FDG avid skeletal lesions were detected; the stage I (n = 5) patients had 10 bone lesions, the stage II (n = 11) patients had 43 lesions, and the stage III (n = 10) patients demonstrated 75 focal bone lesions. F-18 NaF PET/CTs demonstrated fewer myeloma indicative lesions than F-18 FDG PET/CTs. Totally, 57 focal bone lesions were detected with whole body F-18 NaF PET/CT (mean 2.19 ± 0.34, between 1 and 9 lesions); the five stage I patients had 6 bone lesions, the 11 stage II pts had 18 lesions, and the ten stage III patients demonstrated 33 focal bone lesions. On the other hand, F-18 NaF PET/CT demonstrated additional 135 bone lesions defined as rib fractures and other findings due to degenerative changes. In conclusion, our study implies that F-18 NaF PET/CT scan did not actually aid for assessing the myelomatous bone lesions in patients with MM. Therefore, a complementary F-18 NaF PET/CT may be an accurate modality for detecting of bone fracture in patients with MM.

  13. Is there any complimentary role of F-18 NaF PET/CT in detecting of osseous involvement of multiple myeloma? A comparative study for F-18 FDG PET/CT and F-18 FDG NaF PET/CT.

    PubMed

    Ak, İlknur; Onner, Hasan; Akay, Olga Meltem

    2015-09-01

    Multiple myeloma (MM) is a disease characterized by a monoclonal plasma cell population in the bone marrow whereby osseous involvement is a predominant feature. The aim of this prospective study was to investigate the combined use of F-18 FDG and F-18 NaF PET/CT in the skeletal assessment of patients with MM and to compare the efficacy of these two PET tracers regarding detection of myeloma-indicative osseous lesions. A total of 26 patients (14 females and 12 males, mean age 61.8 ± 1.8 years (range 40-81 years)) with MM diagnosed according to standard criteria. All patients underwent both F-18 FDG PET/CT and F-18 NaF PET/CT scans within 1 week after the completion of the usual staging workup for MM. In total, approximately 128 focal F-18 FDG avid skeletal lesions were detected; the stage I (n = 5) patients had 10 bone lesions, the stage II (n = 11) patients had 43 lesions, and the stage III (n = 10) patients demonstrated 75 focal bone lesions. F-18 NaF PET/CTs demonstrated fewer myeloma indicative lesions than F-18 FDG PET/CTs. Totally, 57 focal bone lesions were detected with whole body F-18 NaF PET/CT (mean 2.19 ± 0.34, between 1 and 9 lesions); the five stage I patients had 6 bone lesions, the 11 stage II pts had 18 lesions, and the ten stage III patients demonstrated 33 focal bone lesions. On the other hand, F-18 NaF PET/CT demonstrated additional 135 bone lesions defined as rib fractures and other findings due to degenerative changes. In conclusion, our study implies that F-18 NaF PET/CT scan did not actually aid for assessing the myelomatous bone lesions in patients with MM. Therefore, a complementary F-18 NaF PET/CT may be an accurate modality for detecting of bone fracture in patients with MM. PMID:26068066

  14. Response Assessment and Prediction in Esophageal Cancer Patients via F-18 FDG PET/CT Scans

    NASA Astrophysics Data System (ADS)

    Higgins, Kyle J.

    Purpose: The purpose of this study is to utilize F-18 FDG PET/CT scans to determine an indicator for the response of esophageal cancer patients during radiation therapy. There is a need for such an indicator since local failures are quite common in esophageal cancer patients despite modern treatment techniques. If an indicator is found, a patient's treatment strategy may be altered to possibly improve the outcome. This is investigated with various standard uptake volume (SUV) metrics along with image texture features. The metrics and features showing the most promise and indicating response are used in logistic regression analysis to find an equation for the prediction of response. Materials and Methods: 28 patients underwent F-18 FDG PET/CT scans prior to the start of radiation therapy (RT). A second PET/CT scan was administered following the delivery of ~32 Gray (Gy) of dose. A physician contoured gross tumor volume (GTV) was used to delineate a PET based GTV (GTV-pre-PET) based on a threshold of >40% and >20% of the maximum SUV value in the GTV. Deformable registration was used in VelocityAI software to register the pre-treatment and intra-treatment CT scans so that the GTV-pre-PET contours could be transferred from the pre to intra scans (GTV-intra-PET). The fractional decrease in the maximum, mean, volume to the highest intensity 10%-90%, and combination SUV metrics of the significant previous SUV metrics were compared to post-treatment pathologic response for an indication of response. Next for the >40% threshold, texture features based on a neighborhood gray-tone dimension matrix (NGTDM) were analyzed. The fractional decrease in coarseness, contrast, busyness, complexity, and texture strength were compared to the pathologic response of the patients. From these previous two types of analysis, SUV and texture features, the two most significant results were used in logistic regression analysis to find an equation to predict the probability of a non

  15. Predictive value of intratumoral heterogeneity of F-18 FDG uptake for characterization of thyroid nodules according to Bethesda categories of fine needle aspiration biopsy results.

    PubMed

    Kim, Seong-Jang; Chang, Samuel

    2015-12-01

    The current study was aimed to investigate the clinical value of intratumoral heterogeneity of F-18 FDG uptake for characterization of thyroid nodule (TN) with inconclusive fine-needle aspiration biopsy (FNAB) results. The current study enrolled 200 patients who showed F-18 FDG incidentaloma and were performed FNAB. The intratumoral heterogeneity of F-18 FDG uptake was represented as the heterogeneity factor (HF), defined as the derivative (dV/dT) of a volume-threshold function for a primary tumor. The diagnostic and predictive values of HF and F-18 FDG PET/CT parameters were evaluated for characterization of inconclusive FNAB results. Among F-18 FDG PET/CT parameters, SUVmax, MTV, and TLG of malignant group were statistically higher than those of Bethesda category of suspicious malignant group. However, HF values were not statistically different between the groups of Bethesda categories (Kruskal-Wallis statistics, 9.924; p = 0.0774). In ROC analysis, when HF > 2.751 was used as cut-off value, the sensitivity and specificity for prediction of malignant TN were 100 % (95 % CI 69.2-100 %) and 60 % (95 % CI 42.1-76.1 %), respectively. The AUC was 0.826 (95 % CI 0.684-0.922) and standard error was 0.0648 (p < 0.0001). In conclusion, the intratumoral heterogeneity of F-18 FDG uptake represented by HF could be a predictor for characterization of TN with inconclusive FNAB results. Additional large population-based prospective studies are needed to validate the diagnostic utility of HF of F-18 FDG PET/CT.

  16. Malignant extrarenal rhabdoid tumor of the spine: staging and evaluation of response to therapy with F-18 FDG PET/CT.

    PubMed

    Makis, William; Ciarallo, Anthony; Hickeson, Marc

    2011-07-01

    Malignant extrarenal rhabdoid tumor (ERRT) is a very rare type of soft-tissue sarcoma with a reported incidence of 0.3% of all soft-tissue sarcomas. Only 7 cases of spinal malignant ERRT have been reported in the literature, and to our knowledge, F-18 FDG PET/CT imaging for staging and evaluation of response to therapy for these tumors has not been previously described. This is a case of an 8-month-old boy with malignant ERRT of the spine, who was staged with F-18 FDG PET/CT, and had his tumor burden assessed with PET/CT after chemotherapy, which altered the subsequent chemotherapy regimen. PMID:21637073

  17. Malignant extrarenal rhabdoid tumor of the spine: staging and evaluation of response to therapy with F-18 FDG PET/CT.

    PubMed

    Makis, William; Ciarallo, Anthony; Hickeson, Marc

    2011-07-01

    Malignant extrarenal rhabdoid tumor (ERRT) is a very rare type of soft-tissue sarcoma with a reported incidence of 0.3% of all soft-tissue sarcomas. Only 7 cases of spinal malignant ERRT have been reported in the literature, and to our knowledge, F-18 FDG PET/CT imaging for staging and evaluation of response to therapy for these tumors has not been previously described. This is a case of an 8-month-old boy with malignant ERRT of the spine, who was staged with F-18 FDG PET/CT, and had his tumor burden assessed with PET/CT after chemotherapy, which altered the subsequent chemotherapy regimen.

  18. In vivo characterization of chronic traumatic encephalopathy using [F-18]FDDNP PET brain imaging

    PubMed Central

    Barrio, Jorge R.; Small, Gary W.; Wong, Koon-Pong; Huang, Sung-Cheng; Liu, Jie; Merrill, David A.; Giza, Christopher C.; Fitzsimmons, Robert P.; Omalu, Bennet; Bailes, Julian; Kepe, Vladimir

    2015-01-01

    Chronic traumatic encephalopathy (CTE) is an acquired primary tauopathy with a variety of cognitive, behavioral, and motor symptoms linked to cumulative brain damage sustained from single, episodic, or repetitive traumatic brain injury (TBI). No definitive clinical diagnosis for this condition exists. In this work, we used [F-18]FDDNP PET to detect brain patterns of neuropathology distribution in retired professional American football players with suspected CTE (n = 14) and compared results with those of cognitively intact controls (n = 28) and patients with Alzheimer’s dementia (AD) (n = 24), a disease that has been cognitively associated with CTE. [F-18]FDDNP PET imaging results in the retired players suggested the presence of neuropathological patterns consistent with models of concussion wherein brainstem white matter tracts undergo early axonal damage and cumulative axonal injuries along subcortical, limbic, and cortical brain circuitries supporting mood, emotions, and behavior. This deposition pattern is distinctively different from the progressive pattern of neuropathology [paired helical filament (PHF)-tau and amyloid-β] in AD, which typically begins in the medial temporal lobe progressing along the cortical default mode network, with no or minimal involvement of subcortical structures. This particular [F-18]FDDNP PET imaging pattern in cases of suspected CTE also is primarily consistent with PHF-tau distribution observed at autopsy in subjects with a history of mild TBI and autopsy-confirmed diagnosis of CTE. PMID:25848027

  19. In vivo characterization of chronic traumatic encephalopathy using [F-18]FDDNP PET brain imaging.

    PubMed

    Barrio, Jorge R; Small, Gary W; Wong, Koon-Pong; Huang, Sung-Cheng; Liu, Jie; Merrill, David A; Giza, Christopher C; Fitzsimmons, Robert P; Omalu, Bennet; Bailes, Julian; Kepe, Vladimir

    2015-04-21

    Chronic traumatic encephalopathy (CTE) is an acquired primary tauopathy with a variety of cognitive, behavioral, and motor symptoms linked to cumulative brain damage sustained from single, episodic, or repetitive traumatic brain injury (TBI). No definitive clinical diagnosis for this condition exists. In this work, we used [F-18]FDDNP PET to detect brain patterns of neuropathology distribution in retired professional American football players with suspected CTE (n = 14) and compared results with those of cognitively intact controls (n = 28) and patients with Alzheimer's dementia (AD) (n = 24), a disease that has been cognitively associated with CTE. [F-18]FDDNP PET imaging results in the retired players suggested the presence of neuropathological patterns consistent with models of concussion wherein brainstem white matter tracts undergo early axonal damage and cumulative axonal injuries along subcortical, limbic, and cortical brain circuitries supporting mood, emotions, and behavior. This deposition pattern is distinctively different from the progressive pattern of neuropathology [paired helical filament (PHF)-tau and amyloid-β] in AD, which typically begins in the medial temporal lobe progressing along the cortical default mode network, with no or minimal involvement of subcortical structures. This particular [F-18]FDDNP PET imaging pattern in cases of suspected CTE also is primarily consistent with PHF-tau distribution observed at autopsy in subjects with a history of mild TBI and autopsy-confirmed diagnosis of CTE.

  20. Non-invasive imaging of atherosclerotic plaque macrophage in a rabbit model with F-18 FDG PET: a histopathological correlation

    PubMed Central

    Zhang, Zhuangyu; Machac, Josef; Helft, Gerard; Worthley, Stephen G; Tang, Cheuk; Zaman, Azfar G; Rodriguez, Oswaldo J; Buchsbaum, Monte S; Fuster, Valentin; Badimon, Juan J

    2006-01-01

    Background Coronary atherosclerosis and its thrombotic complications are the major cause of mortality and morbidity throughout the industrialized world. Thrombosis on disrupted atherosclerotic plaques plays a key role in the onset of acute coronary syndromes. Macrophages density is one of the most critical compositions of plaque in both plaque vulnerability and thrombogenicity upon rupture. It has been shown that macrophages have a high uptake of 18F-FDG (FDG). We studied the correlation of FDG uptake with histopathological macrophage accumulation in atherosclerotic plaques in a rabbit model. Methods Atherosclerosis was induced in rabbits (n = 6) by a combination of atherogenic diet and balloon denudation of the aorta. PET imaging was performed at baseline and 2 months after atherogenic diet and coregistered with magnetic resonance (MR) imaging. Normal (n = 3) rabbits served as controls. FDG uptake by the thoracic aorta was expressed as concentration (μCi/ml) and the ratio of aortic uptake-to-blood radioactivity. FDG uptake and RAM-11 antibody positive areas were analyzed in descending aorta. Results Atherosclerotic aortas showed significantly higher uptake of FDG than normal aortas. The correlation of aortic FDG uptake with macrophage areas assessed by histopathology was statistically significant although it was not high (r = 0.48, p < 0.0001). When uptake was expressed as the ratio of aortic uptake-to-blood activity, it correlated better (r = 0.80, p < 0.0001) with the macrophage areas, due to the correction for residual blood FDG activity. Conclusion PET FDG activity correlated with macrophage content within aortic atherosclerosis. This imaging approach might serve as a useful non-invasive imaging technique and potentially permit monitoring of relative changes in inflammation within the atherosclerotic lesion. PMID:16725052

  1. Additional value of F-18 FDG PET/CT for initial staging in breast cancer with clinically negative axillary nodes.

    PubMed

    Jeong, Young Jin; Kang, Do-Young; Yoon, Hyun Jin; Son, Hye Joo

    2014-05-01

    The aim of this study was to evaluate the clinical impact of the preoperative ¹⁸F-FDG PET/CT in the initial workup of breast cancer with clinically negative axillary nodes. Whether the status of the clinical axillary nodal involvement can be considered a parameter for making a decision to omit the preoperative ¹⁸F-FDG PET/CT in the situation reported herein was also determined. A total of 178 patients who had newly diagnosed breast cancer and for whom the conventional diagnostic modalities showed no sign of axillary node metastasis were retrospectively enrolled in this study. All the patients underwent preoperative ¹⁸F-FDG PET/CT. The images and histologic results that were obtained were analyzed. ¹⁸F-FDG PET/CT detected primary lesions in 156 of the 178 patients, with an overall sensitivity of 87.6 %, and false negative results were obtained for 22 patients (12.4 %). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of ¹⁸F-FDG PET/CT in the detection of axillary nodes were 20.8, 86.9, 37.0, 74.8, and 69.1 %, respectively. Extra-axillary node metastasis was identified in two patients (1.1 %) who had internal mammary nodes. There was no distant metastasis, but coexisting primary tumor was detected in five patients (2.8 %). In total, the therapeutic plan was changed based on ¹⁸F-FDG PET/CT in seven (3.9 %) of the 178 patients, but considering only the cases confined to breast cancer, the change occurred in only two patients (1.1 %). ¹⁸F-FDG PET/CT almost did not affect the initial staging and treatment plan in breast cancer with clinically negative axillary node. If the axillary node is clinically negative in the preoperative workup of breast cancer, then ¹⁸F-FDG PET/CT can be omitted.

  2. Three-dimensional texture analysis of contrast enhanced CT images for treatment response assessment in Hodgkin lymphoma: Comparison with F-18-FDG PET

    SciTech Connect

    Knogler, Thomas; El-Rabadi, Karem; Weber, Michael; Karanikas, Georgios; Mayerhoefer, Marius E.

    2014-12-15

    Purpose: To determine the diagnostic performance of three-dimensional (3D) texture analysis (TA) of contrast-enhanced computed tomography (CE-CT) images for treatment response assessment in patients with Hodgkin lymphoma (HL), compared with F-18-fludeoxyglucose (FDG) positron emission tomography/CT. Methods: 3D TA of 48 lymph nodes in 29 patients was performed on venous-phase CE-CT images before and after chemotherapy. All lymph nodes showed pathologically elevated FDG uptake at baseline. A stepwise logistic regression with forward selection was performed to identify classic CT parameters and texture features (TF) that enable the separation of complete response (CR) and persistent disease. Results: The TF fraction of image in runs, calculated for the 45° direction, was able to correctly identify CR with an accuracy of 75%, a sensitivity of 79.3%, and a specificity of 68.4%. Classical CT features achieved an accuracy of 75%, a sensitivity of 86.2%, and a specificity of 57.9%, whereas the combination of TF and CT imaging achieved an accuracy of 83.3%, a sensitivity of 86.2%, and a specificity of 78.9%. Conclusions: 3D TA of CE-CT images is potentially useful to identify nodal residual disease in HL, with a performance comparable to that of classical CT parameters. Best results are achieved when TA and classical CT features are combined.

  3. Predictive Role of Functional Visceral Fat Activity Assessed by Preoperative F-18 FDG PET/CT for Regional Lymph Node or Distant Metastasis in Patients with Colorectal Cancer

    PubMed Central

    Pahk, Kisoo; Rhee, Seunghong; Kim, Sungeun; Choe, Jae Gol

    2016-01-01

    Objectives To investigate the role of functional visceral fat activity assessed by preoperative F-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in colorectal cancer (CRC) for predicting regional lymph node (LN) or distant metastasis. Method We evaluated 131 patients with newly diagnosed CRC. They all underwent pre-operative 18F-FDG PET/CT and surgery. Functional fat activity was measured by maximum standardized uptake value (SUVmax) using 18F-FDG PET/CT. Functional visceral fat activity was measured by SUVmax of visceral fat/SUVmax of subcutaneous fat (V/S) ratio. Mann-Whitney U test, χ2 test, Fisher’s exact test, receiver-operating characteristic (ROC) analysis, Spearrman’s correlation coefficient, and uni- and multivariate logistic regression statistical analyses were done. Results Patients with higher V/S ratio displayed a significantly higher rate of regional LN (p = 0.004) and distant metastasis (p<0.001). In addition, V/S ratio was the only factor that was significantly associated with distant metastasis. An optimal cut-off V/S ratio of 1.88 was proposed for predicting distant metastasis with a sensitivity of 84.6% and specificity of 78.8% (area under the curve: 0.86; p<0.0001) Conclusion Functional visceral fat activity is significantly associated with distant metastasis in CRC patients. Furthermore, V/S ratio can be useful as a complementary factor in predicting distant metastasis. PMID:26862754

  4. Detection of an Infected N-butyl-2-cyanoacrylate Plug by F-18 FDG PET/CT Scan in a Patient Who Received Endoscopic Intervention for Gastric Variceal Bleeding.

    PubMed

    Joo, Kowoon; Hyun, In Young; Baek, Ji Hyeon; Chung, Moon-Hyun; Lee, Jin-Soo

    2013-06-01

    Injection of N-butyl-2-cyanoacrylate has been used successfully for treatment of gastric variceal bleeding. Bacteremia after injection of N-butyl-2-cyanoacrylate is well known, however, the method for diagnosis of infected endovascular injected material has remained uncertain. This is the first case reporting use of F-18 FDG PET/CT in detection of the source of infection after control of endoscopic bleeding with N-butyl-2-cyanoacrylate.

  5. Correlation of amyloid PET ligand florbetapir F 18 (18F-AV-45) binding with β-amyloid aggregation and neuritic plaque deposition in postmortem brain tissue

    PubMed Central

    Choi, Seok Rye; Schneider, Julie A.; Bennett, David A.; Beach, Thomas G.; Bedell, Barry J.; Zehntner, Simone P.; Krautkramer, Michael; Kung, Hank F.; Skovronsky, Daniel M.; Hefti, Franz; Clark, Christopher M.

    2011-01-01

    Background Florbetapir F 18 (18F-AV-45) is a positron emission tomography (PET) imaging ligand for the detection of amyloid aggregation associated with Alzheimer’s disease. Earlier data showed that florbetapir F 18 binds with high affinity to β-amyloid plaques in human brain homogenates (Kd = 3.7 nM) and has favorable imaging pharmacokinetic properties, including rapid brain penetration and washout. The present study used human autopsy brain tissue to evaluate the correlation between in vitro florbetapir F 18 binding and β-amyloid density measured by established neuropathological methods. Methods The localization and density of florbetapir F 18 binding in frozen and formalin-fixed paraffin-embedded sections of postmortem brain tissue from 40 subjects with a varying degree of neurodegenerative pathology was assessed by standard florbetapir F 18 autoradiography and correlated with the localization and density of β-amyloid identified by silver staining, thioflavin S staining, and immunohistochemistry. Results There were strong quantitative correlations between florbetapir F 18 tissue binding and both β-amyloid plaques identified by light microscopy (sliver staining and thioflavin S fluorescence) and by immunohistochemical measurements of β-amyloid using three antibodies recognizing different epitopes of the β-amyloid peptide (Aβ). Florbetapir F 18 did not bind to neurofibrillary tangles. Conclusion Florbetapir F 18 selectively binds β-amyloid in human brain tissue. The binding intensity was quantitatively correlated with the density of β-amyloid plaques identified by standard neuropathological techniques and correlated with the density of Aβ measured by immunohistochemistry. Since β-amyloid plaques are a defining neuropathological feature for Alzheimer’s disease, these results support the use of florbetapir F 18 as an amyloid PET ligand to identify the presence of AD pathology in patients with signs and symptoms of progressive late-life cognitive

  6. Monte Carlo estimation of radiation dose in organs of female and male adult phantoms due to FDG-F18 absorbed in the lungs

    NASA Astrophysics Data System (ADS)

    Belinato, Walmir; Santos, William S.; Silva, Rogério M. V.; Souza, Divanizia N.

    2014-03-01

    The determination of dose conversion factors (S values) for the radionuclide fluorodeoxyglucose (18F-FDG) absorbed in the lungs during a positron emission tomography (PET) procedure was calculated using the Monte Carlo method (MCNPX version 2.7.0). For the obtained dose conversion factors of interest, it was considered a uniform absorption of radiopharmaceutical by the lung of a healthy adult human. The spectrum of fluorine was introduced in the input data file for the simulation. The simulation took place in two adult phantoms of both sexes, based on polygon mesh surfaces called FASH and MASH with anatomy and posture according to ICRP 89. The S values for the 22 internal organs/tissues, chosen from ICRP No. 110, for the FASH and MASH phantoms were compared with the results obtained from a MIRD V phantoms called ADAM and EVA used by the Committee on Medical Internal Radiation Dose (MIRD). We observed variation of more than 100% in S values due to structural anatomical differences in the internal organs of the MASH and FASH phantoms compared to the mathematical phantom.

  7. SU-D-9A-02: Relative Effects of Threshold Choice and Spatial Resolution Modeling On SUV and Volume Quantification in F18-FDG PET Imaging of Anal Cancer Patients

    SciTech Connect

    Zhao, F; Bowsher, J; Palta, M; Czito, B; Willett, C; Yin, F

    2014-06-01

    Purpose: PET imaging with F18-FDG is utilized for treatment planning, treatment assessment, and prognosis. A region of interest (ROI) encompassing the tumor may be determined on the PET image, often by a threshold T on the PET standard uptake values (SUVs). Several studies have shown prognostic value for relevant ROI properties including maximum SUV value (SUVmax), metabolic tumor volume (MTV), and total glycolytic activity (TGA). The choice of threshold T may affect mean SUV value (SUVmean), MTV, and TGA. Recently spatial resolution modeling (SRM) has been introduced on many PET systems. SRM may also affect these ROI properties. The purpose of this work is to investigate the relative influence of SRM and threshold choice T on SUVmean, MTV, TGA, and SUVmax. Methods: For 9 anal cancer patients, 18F-FDG PET scans were performed prior to treatment. PET images were reconstructed by 2 iterations of Ordered Subsets Expectation Maximization (OSEM), with and without SRM. ROI contours were generated by 5 different SUV threshold values T: 2.5, 3.0, 30%, 40%, and 50% of SUVmax. Paired-samples t tests were used to compare SUVmean, MTV, and TGA (a) for SRM on versus off and (b) between each pair of threshold values T. SUVmax was also compared for SRM on versus off. Results: For almost all (57/60) comparisons of 2 different threshold values, SUVmean, MTV, and TGA showed statistically significant variation. For comparison of SRM on versus off, there were no statistically significant changes in SUVmax and TGA, but there were statistically significant changes in MTV for T=2.5 and T=3.0 and in SUVmean for all T. Conclusion: The near-universal statistical significance of threshold choice T suggests that, regarding harmonization across sites, threshold choice may be a greater concern than choice of SRM. However, broader study is warranted, e.g. other iterations of OSEM should be considered.

  8. Effect of Donepezil on Wernicke Aphasia After Bilateral Middle Cerebral Artery Infarction: Subtraction Analysis of Brain F-18 Fluorodeoxyglucose Positron Emission Tomographic Images.

    PubMed

    Yoon, Seo Yeon; Kim, Je-Kyung; An, Young-Sil; Kim, Yong Wook

    2015-01-01

    Aphasia is one of the most common neurologic deficits occurring after stroke. Although the speech-language therapy is a mainstream option for poststroke aphasia, pharmacotherapy is recently being tried to modulate different neurotransmitter systems. However, the efficacy of those treatments is still controversial. We present a case of a 53-year-old female patient with Wernicke aphasia, after the old infarction in the territory of left middle cerebral artery for 8 years and the recent infarction in the right middle cerebral artery for 4 months. On the initial evaluation, the Aphasia Quotient in Korean version of the Western Aphasia Battery was 25.6 of 100. Baseline brain F-18 fluorodeoxyglucose positron emission tomographic images demonstrated a decreased cerebral metabolism in the left temporoparietal area and right temporal lobe. Donepezil hydrochloride, a reversible acetylcholinesterase inhibitor, was orally administered 5 mg/d for 6 weeks after the initial evaluation and was increased to 10 mg/d for the following 6 weeks. After the donepezil treatment, the patient showed improvement in language function, scoring 51.0 of 100 on Aphasia Quotient. A subtraction analysis of the brain F-18 fluorodeoxyglucose positron emission tomographic images after donepezil medication demonstrated increased uptake in both middle temporal gyri, extended to the occipital area and the left cerebellum. Thus, we suggest that donepezil can be an effective therapeutic choice for the treatment of Wernicke aphasia.

  9. F-18 HARV cockpit

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The F-18 HARV retains the basic F-18 cockpit controls with some exceptions. The pilot's center control stick is relatively typical of a modern fighter aircraft. The F-18 HARV has no weapons delivery capability. Independent throttling of the left or right engine is possible through split throttle levers located on the left console. The pilot's friction control is provided for adjustment of throttle lever force. The three-position (extend, hold, and retract) speed brake thumb switch is located on the inboard side of the right-engine throttle lever. The primary cockpit displays include a left- and right-side cathode-ray tube display, referred to as the DDIs, and the heads-up display (HUD). The DDIs and HUD are generally used to display primary flight condition information such as airspeed, altitude, altitude rate, attitude, heading, RFCS status, etc. Other flight conditions displayed include angle of attack (AOA), Mach number, and load factor. The HUD also provides primary flight condition information to the pilot without having to refer to the DDIs. Select flight controls information also can be presented on the HUD. The twenty pushbuttons located on the periphery of each DDI are used to select a variety of displays for pilot interrogation of F-18 HARV systems. These displays are pilot selectable and menu driven. Various aerodynamic research experiments were conducted on the F-18 HARV. Switches for control of these experiments were located on the research systems control panel located at the lower center of the instrument panel. These switches operated in conjunction with the gun trigger switch. The configuration of this panel and the function of the gun trigger switch varied with the particular experiment flown.

  10. [F-18]FDDNP microPET imaging correlates with brain Aβ burden in a transgenic rat model of Alzheimer disease: effects of aging, in vivo blockade, and anti-Aβ antibody treatment.

    PubMed

    Teng, Edmond; Kepe, Vladimir; Frautschy, Sally A; Liu, Jie; Satyamurthy, Nagichettiar; Yang, Fusheng; Chen, Ping-Ping; Cole, Graham B; Jones, Mychica R; Huang, Sung-Cheng; Flood, Dorothy G; Trusko, Stephen P; Small, Gary W; Cole, Gregory M; Barrio, Jorge R

    2011-09-01

    In vivo detection of Alzheimer's disease (AD) neuropathology in living patients using positron emission tomography (PET) in conjunction with high affinity molecular imaging probes for β-amyloid (Aβ) and tau has the potential to assist with early diagnosis, evaluation of disease progression, and assessment of therapeutic interventions. Animal models of AD are valuable for exploring the in vivo binding of these probes, particularly their selectivity for specific neuropathologies, but prior PET experiments in transgenic mice have yielded conflicting results. In this work, we utilized microPET imaging in a transgenic rat model of brain Aβ deposition to assess [F-18]FDDNP binding profiles in relation to age-associated accumulation of neuropathology. Cross-sectional and longitudinal imaging demonstrated that [F-18]FDDNP binding in the hippocampus and frontal cortex progressively increases from 9 to 18months of age and parallels age-associated Aβ accumulation. Specificity of in vivo [F-18]FDDNP binding was assessed by naproxen pretreatment, which reversibly blocked [F-18]FDDNP binding to Aβ aggregrates. Both [F-18]FDDNP microPET imaging and neuropathological analyses revealed decreased Aβ burden after intracranial anti-Aβ antibody administration. The combination of this non-invasive imaging method and robust animal model of brain Aβ accumulation allows for future longitudinal in vivo assessments of potential therapeutics for AD that target Aβ production, aggregation, and/or clearance. These results corroborate previous analyses of [F-18]FDDNP PET imaging in clinical populations.

  11. Radiolabeling of Poly(lactic-co-glycolic acid) (PLGA) Nanoparticles with Biotinylated F-18 Prosthetic Groups and Imaging of Their Delivery to the Brain with Positron Emission Tomography

    PubMed Central

    2015-01-01

    The avidin–biotin interaction permits rapid and nearly irreversible noncovalent linkage between biotinylated molecules and avidin-modified substrates. We designed a biotinylated radioligand intended for use in the detection of avidin-modified polymer nanoparticles in tissue with positron emission tomography (PET). Using an F-18 labeled prosthetic group, [18F]4-fluorobenzylamine, and a commercially available biotin derivate, NHS-PEG4-biotin, [18F]-fluorobenzylamide-poly(ethylene glycol)4-biotin ([18F]NPB4) was prepared with high purity and specific activity. The attachment of the [18F]NPB4 radioligand to avidin-modified poly(lactic-co-glycolic acid) (PLGA) nanoparticles was tested by using PET imaging to measure the kinetics of convection-enhanced delivery (CED) of nanoparticles of varying size to the rat brain. PET imaging enabled the direct observation of nanoparticle delivery by measurement of the spatial volume of distribution of radiolabeled nanoparticles as a function of time, both during and after the infusion. This work thus validates new methods for radiolabeling PEG-biotin derivatives and also provides insight into the fate of nanoparticles that have been infused directly into the brain. PMID:25322194

  12. F-18 FDG PET/CT and Tc-99m sulfur colloid SPECT imaging in the diagnosis and treatment of a case of dual solitary fibrous tumors of the retroperitoneum and pancreas.

    PubMed

    Azadi, Javad; Subhawong, Andrea; Durand, Daniel James

    2012-03-01

    Although FDG PET is increasingly used for the staging of many types of sarcoma, little has been written regarding the FDG PET imaging characteristics of solitary fibrous tumor. We report a patient undergoing FDG PET/CT surveillance for squamous cell carcinoma of the tongue who was incidentally found to have two soft tissue masses in the retroperitoneum and pancreatic tail. Due to their low degree of FDG avidity, they were followed conservatively for approximately one year as they gradually increased in size. Technetium-99m sulfur colloid SPECT helped confirm that the pancreatic tail mass was not a splenule, after which both lesions were surgically resected and found to be extrathoracic solitary fibrous tumors without malignant features. These findings suggest that, as with other low-grade sarcomas, benign extrathoracic solitary fibrous tumors exhibit relatively little glycolytic metabolism in vivo.

  13. Dynamic functional imaging of brain glucose utilization using fPET-FDG

    DOE PAGES

    Villien, Marjorie; Wey, Hsiao-Ying; Mandeville, Joseph B.; Catana, Ciprian; Polimeni, Jonathan R.; Sander, Christin Y.; Zürcher, Nicole R.; Chonde, Daniel B.; Fowler, Joanna S.; Rosen, Bruce R.; et al

    2014-06-14

    We report that glucose is the principal source of energy for the brain and yet the dynamic response of glucose utilization to changes in brain activity is still not fully understood. Positron emission tomography (PET) allows quantitative measurement of glucose metabolism using 2-[18F]-fluorodeoxyglucose (FDG). However, FDG PET in its current form provides an integral (or average) of glucose consumption over tens of minutes and lacks the temporal information to capture physiological alterations associated with changes in brain activity induced by tasks or drug challenges. Traditionally, changes in glucose utilization are inferred by comparing two separate scans, which significantly limits themore » utility of the method. We report a novel method to track changes in FDG metabolism dynamically, with higher temporal resolution than exists to date and within a single session. Using a constant infusion of FDG, we demonstrate that our technique (termed fPET-FDG) can be used in an analysis pipeline similar to fMRI to define within-session differential metabolic responses. We use visual stimulation to demonstrate the feasibility of this method. Ultimately, this new method has a great potential to be used in research protocols and clinical settings since fPET-FDG imaging can be performed with most PET scanners and data acquisition and analysis are straightforward. fPET-FDG is a highly complementary technique to MRI and provides a rich new way to observe functional changes in brain metabolism.« less

  14. Dynamic functional imaging of brain glucose utilization using fPET-FDG

    SciTech Connect

    Villien, Marjorie; Wey, Hsiao-Ying; Mandeville, Joseph B.; Catana, Ciprian; Polimeni, Jonathan R.; Sander, Christin Y.; Zürcher, Nicole R.; Chonde, Daniel B.; Fowler, Joanna S.; Rosen, Bruce R.; Hooker, Jacob M.

    2014-06-14

    We report that glucose is the principal source of energy for the brain and yet the dynamic response of glucose utilization to changes in brain activity is still not fully understood. Positron emission tomography (PET) allows quantitative measurement of glucose metabolism using 2-[18F]-fluorodeoxyglucose (FDG). However, FDG PET in its current form provides an integral (or average) of glucose consumption over tens of minutes and lacks the temporal information to capture physiological alterations associated with changes in brain activity induced by tasks or drug challenges. Traditionally, changes in glucose utilization are inferred by comparing two separate scans, which significantly limits the utility of the method. We report a novel method to track changes in FDG metabolism dynamically, with higher temporal resolution than exists to date and within a single session. Using a constant infusion of FDG, we demonstrate that our technique (termed fPET-FDG) can be used in an analysis pipeline similar to fMRI to define within-session differential metabolic responses. We use visual stimulation to demonstrate the feasibility of this method. Ultimately, this new method has a great potential to be used in research protocols and clinical settings since fPET-FDG imaging can be performed with most PET scanners and data acquisition and analysis are straightforward. fPET-FDG is a highly complementary technique to MRI and provides a rich new way to observe functional changes in brain metabolism.

  15. FDG PET of the brain in pediatric patients: imaging spectrum with MR imaging correlation.

    PubMed

    Stanescu, Luana; Ishak, Gisele E; Khanna, Paritosh C; Biyyam, Deepa R; Shaw, Dennis W; Parisi, Marguerite T

    2013-01-01

    Positron emission tomography (PET) of the brain is an important problem-solving tool in pediatric neuroimaging, neurology, and neurosurgery. Fluorine 18 fluorodeoxyglucose (FDG) PET or dual-modality PET and computed tomographic (CT) imaging (PET/CT), with magnetic resonance (MR) imaging correlation, can be used to evaluate childhood epilepsy and pediatric brain tumors, areas in which PET adds value in patient management. FDG PET has been widely used in pediatric temporal lobe epilepsy, most commonly manifesting as mesial temporal sclerosis, which demonstrates hypometabolism at interictal PET and hypermetabolism during seizures. Recently, FDG PET has shown added value for patients with extratemporal epilepsy, in whom FDG PET can help identify cortical foci of interictal hypometabolism that are undetectable or difficult to detect with MR imaging. These findings can then guide additional investigations and surgery. FDG PET also enhances medical decision making in children with brain tumors, in whom FDG PET can be used to (a) improve the diagnostic yield of stereotactic biopsies by detecting metabolically active areas of tumor, (b) help guide the surgeon in achieving total tumor resection, and (c) increase detection of residual or recurrent tumor. Technologic advances in the past decade have allowed fusion of PET and MR images, combining the high resolution of MR imaging with the low-resolution functional capability of PET. As dual-modality integrated PET/MR imaging systems become available, CT coregistration for PET can be eliminated, thus reducing patient radiation exposure. Increasing familiarity with normal and abnormal appearances of FDG PET brain images correlated with MR images can enhance diagnostic yield and improve the care of children with epilepsy and brain tumors.

  16. Validation of true low-dose 18F-FDG PET of the brain

    PubMed Central

    Fällmar, David; Lilja, Johan; Kilander, Lena; Danfors, Torsten; Lubberink, Mark; Larsson, Elna-Marie; Sörensen, Jens

    2016-01-01

    The dosage of 18F-FDG must be sufficient to ensure adequate PET image quality. For younger patients and research controls, the lowest possible radiation dose should be used. The purpose of this study was to find a protocol for FDG-PET of the brain with reduced radiation dose and preserved quantitative characteristics. Eight patients with neurodegenerative disorders and nine controls (n=17) underwent FDG-PET/CT twice on separate occasions, first with normal-dose (3 MBq/kg), and second with low-dose (0.75 MBq/kg, 25% of the original). Five additional controls (total n=22) underwent FDG-PET twice, using normal-dose and ultra-low-dose (0.3 MBq/kg, 10% of original). All subjects underwent MRI. Ten-minute summation images were spatially normalized and intensity normalized. Regional standard uptake value ratios (SUV-r) were calculated using an automated atlas. SUV-r values from the normal- and low-dose images were compared pairwise. No clinically significant bias was found in any of the three groups. The mean absolute difference in regional SUV-r values was 0.015 (1.32%) in controls and 0.019 (1.67%) in patients. The ultra-low-dose protocol produced a slightly higher mean difference of 0.023 (2.10%). The main conclusion is that 0.75 MBq/kg (56 MBq for a 75-kg subject) is a sufficient FDG dose for evaluating regional SUV-ratios in brain PET scans in adults with or without neurodegenerative disease, resulting in a reduction of total PET/CT effective dose from 4.54 to 1.15 mSv. The ultra-low-dose (0.5 mSv) could be useful in research studies requiring serial PET in healthy controls or children. PMID:27766185

  17. Brain-Only Metastases Seen on FDG PET as First Relapse of Papillary Thyroid Carcinoma Two Years Post-Thyroidectomy.

    PubMed

    Naddaf, Sleiman Y; Syed, Ghulam Mustafa Shah; Hadb, Abdulrahman; Al-Thaqfi, Saif

    2016-09-01

    We report a case of a 60-year-old man diagnosed with papillary thyroid cancer who had a relapse seen only in the brain at FDG PET on standard images. Total thyroidectomy was performed in July 2013 after initial diagnosis. Patient received I ablation in December 2013, followed by external beam radiotherapy to the neck. In September 2015, the patient presented with neurological symptoms. Brain MRI showed multiple brain metastases later confirmed on histopathology. An FDG PET/CT scan was performed to evaluate the whole body in November 2015. Multiple hypermetabolic lesions were identified in the brain with no other lesion up to mid thighs. PMID:27405041

  18. Positron Emission Tomography Using Fluorine F 18 EF5 to Find Oxygen in Tumor Cells of Patients Who Are Undergoing Surgery or Biopsy for Newly Diagnosed Brain Tumors

    ClinicalTrials.gov

    2013-01-15

    Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Central Nervous System Germ Cell Tumor; Adult Choroid Plexus Tumor; Adult Craniopharyngioma; Adult Diffuse Astrocytoma; Adult Ependymoblastoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Grade I Meningioma; Adult Grade II Meningioma; Adult Grade III Meningioma; Adult Medulloblastoma; Adult Meningeal Hemangiopericytoma; Adult Mixed Glioma; Adult Myxopapillary Ependymoma; Adult Oligodendroglioma; Adult Pilocytic Astrocytoma; Adult Pineoblastoma; Adult Pineocytoma; Adult Subependymoma; Adult Supratentorial Primitive Neuroectodermal Tumor (PNET); Meningeal Melanocytoma

  19. FDG-PET mapping the brain substrates of visuo-constructive processing in Alzheimer's disease.

    PubMed

    Förster, Stefan; Teipel, Stefan; Zach, Christian; Rominger, Axel; Cumming, Paul; Fougere, Christian la; Yakushev, Igor; Haslbeck, Marianne; Hampel, Harald; Bartenstein, Peter; Bürger, Katharina

    2010-05-01

    The anatomical basis of visuo-constructive impairment in AD is widely unexplored. FDG-PET can be used to determine functional neuronal networks underlying specific cognitive performance in the human brain. In the present study, we determined the pattern of cortical metabolism that was associated with visuo-constructive performance in AD. We employed two widely used visuo-constructive tests that differ in their demand on visual perception and processing capacity. Resting state FDG-PET scans were obtained in 29 probable AD patients, and cognitive tests were administered. We made a voxel-based regression analysis of FDG uptake to scores in visual test performance, using the SPM5 software. Performance in the CERAD Drawing test correlated with FDG uptake in the bilateral inferior temporal gyri, bilateral precuneus, right cuneus, right supramarginal gyrus and right middle temporal gyrus covering areas of dorsal and ventral visual streams. In contrast, performance in the more complex RBANS Figure Copy test correlated with FDG uptake in the bilateral fusiform gyri, right inferior temporal gyrus, left anterior cingulate gyrus, left parahippocampal gyrus, right middle temporal gyrus and right insula, encompassing the ventral visual stream and areas of higher-level visual processing. The study revealed neuronal networks underlying impaired visual test performance in AD. The extent of involvement of visual and higher order association cortex increased with greater test complexity. From a clinical point of view, both of these widely used visual tests evaluate the integrity of complementary cortical networks and may contribute complementary information on the integrity of visual processing in AD. PMID:19875130

  20. FDG-PET imaging in mild traumatic brain injury: a critical review

    PubMed Central

    Byrnes, Kimberly R.; Wilson, Colin M.; Brabazon, Fiona; von Leden, Ramona; Jurgens, Jennifer S.; Oakes, Terrence R.; Selwyn, Reed G.

    2013-01-01

    Traumatic brain injury (TBI) affects an estimated 1.7 million people in the United States and is a contributing factor to one third of all injury related deaths annually. According to the CDC, approximately 75% of all reported TBIs are concussions or considered mild in form, although the number of unreported mild TBIs (mTBI) and patients not seeking medical attention is unknown. Currently, classification of mTBI or concussion is a clinical assessment since diagnostic imaging is typically inconclusive due to subtle, obscure, or absent changes in anatomical or physiological parameters measured using standard magnetic resonance (MR) or computed tomography (CT) imaging protocols. Molecular imaging techniques that examine functional processes within the brain, such as measurement of glucose uptake and metabolism using [18F]fluorodeoxyglucose and positron emission tomography (FDG-PET), have the ability to detect changes after mTBI. Recent technological improvements in the resolution of PET systems, the integration of PET with magnetic resonance imaging (MRI), and the availability of normal healthy human databases and commercial image analysis software contribute to the growing use of molecular imaging in basic science research and advances in clinical imaging. This review will discuss the technological considerations and limitations of FDG-PET, including differentiation between glucose uptake and glucose metabolism and the significance of these measurements. In addition, the current state of FDG-PET imaging in assessing mTBI in clinical and preclinical research will be considered. Finally, this review will provide insight into potential critical data elements and recommended standardization to improve the application of FDG-PET to mTBI research and clinical practice. PMID:24409143

  1. Evaluation of 18F-FDG PET and MRI Associations in Pediatric Diffuse Intrinsic Brain stem Glioma: A Report from the Pediatric Brain Tumor Consortium

    PubMed Central

    Zukotynski, Katherine A.; Fahey, Frederic H.; Kocak, Mehmet; Alavi, Abass; Wong, Terence Z.; Treves, S. Ted; Shulkin, Barry L.; Haas-Kogan, Daphne A.; Geyer, J. Russell; Vajapeyam, Sridhar; Boyett, James M.; Kun, Larry E.; Poussaint, Tina Young

    2012-01-01

    Rationale To assess 18F-labeled 2-fluoro-2-deoxy-D-glucose (18F-FDG) uptake in children with a newly diagnosed diffuse intrinsic brainstem glioma (BSG) and to investigate associations with progression-free survival (PFS), overall survival (OS) and MRI indices. Methods Two Pediatric Brain Tumor Consortium (PBTC) therapeutic trials in children with newly diagnosed BSG were designed to test radiation therapy combined with molecularly targeted agents (PBTC-007: Phase I/II study of gefitinib; PBTC-014: Phase I/II study of tipifarnib). Baseline brain 18F-FDG PET scans were obtained in 40 children in these trials. Images were evaluated by consensus of two PET experts for intensity and uniformity of tracer uptake. Associations of 18F-FDG uptake intensity and uniformity with both PFS and OS were evaluated as well as associations with tumor MRI indices at baseline (tumor volume on FLAIR, baseline intratumoral enhancement, diffusion and perfusion values. Results In the majority of children, BSG 18F-FDG uptake was less than gray matter uptake. Survival was poor irrespective of intensity of 18F-FDG uptake, with no association between intensity of 18F-FDG uptake and PFS or OS. However, hyperintense 18F-FDG uptake in tumor compared to gray matter suggested poorer survival rates. Patients with 18F-FDG uptake in ≥ 50% of the tumor had shorter PFS and OS compared to patients with 18F-FDG uptake in < 50% of tumor. There was some evidence that tumors with higher 18F-FDG uptake were more likely to show enhancement; and when the diffusion ratio was lower the uniformity of 18F- FDG uptake appeared higher. Conclusion Children with BSG where 18F-FDG uptake involves at least half the tumor appear to have inferior survival compared to children with uptake in <50% of tumor. A larger independent study is needed to verify this hypothesis. Intense tracer uptake in the tumors compared to gray matter suggests decreased survival. Higher 18F-FDG uptake within the tumor was associated with

  2. Quantitative characterization of brain β-amyloid using a joint PiB/FDG PET image histogram

    NASA Astrophysics Data System (ADS)

    Camp, Jon J.; Hanson, Dennis P.; Holmes, David R.; Kemp, Bradley J.; Senjem, Matthew L.; Murray, Melissa E.; Dickson, Dennis W.; Parisi, Joseph; Petersen, Ronald C.; Lowe, Val J.; Robb, Richard A.

    2014-03-01

    A complex analysis performed by spatial registration of PiB and MRI patient images in order to localize the PiB signal to specific cortical brain regions has been proven effective in identifying imaging characteristics associated with underlying Alzheimer's Disease (AD) and Lewy Body Disease (LBD) pathology. This paper presents an original method of image analysis and stratification of amyloid-related brain disease based on the global spatial correlation of PiB PET images with 18F-FDG PET images (without MR images) to categorize the PiB signal arising from the cortex. Rigid registration of PiB and 18F-FDG images is relatively straightforward, and in registration the 18F-FDG signal serves to identify the cortical region in which the PiB signal is relevant. Cortical grey matter demonstrates the highest levels of amyloid accumulation and therefore the greatest PiB signal related to amyloid pathology. The highest intensity voxels in the 18F-FDG image are attributed to the cortical grey matter. The correlation of the highest intensity PiB voxels with the highest 18F-FDG values indicates the presence of β-amyloid protein in the cortex in disease states, while correlation of the highest intensity PiB voxels with mid-range 18F-FDG values indicates only nonspecific binding in the white matter.

  3. 18F-FDG PET and MR Imaging Associations Across a Spectrum of Pediatric Brain Tumors: A Report from the Pediatric Brain Tumor Consortium

    PubMed Central

    Zukotynski, Katherine; Fahey, Frederic; Kocak, Mehmet; Kun, Larry; Boyett, James; Fouladi, Maryam; Vajapeyam, Sridhar; Treves, Ted; Poussaint, Tina Y.

    2014-01-01

    The purpose of this study was to describe 18F-FDG uptake across a spectrum of pediatric brain tumors and correlate 18F-FDG PET with MR imaging variables, progression-free survival (PFS), and overall survival (OS). Methods A retrospective analysis was conducted of children enrolled in phase I/II clinical trials through the Pediatric Brain Tumor Consortium from August 2000 to June 2010. PET variables were summarized within diagnostic categories using descriptive statistics. Associations of PET with MR imaging variables and PFS and OS by tumor types were evaluated. Results Baseline 18F-FDG PET was available in 203 children; 66 had newly diagnosed brain tumors, and 137 had recurrent/refractory brain tumors before enrolling in a Pediatric Brain Tumor Consortium trial. MR imaging was performed within 2 wk of PET and before therapy in all cases. The 18F-FDG uptake pattern and MR imaging contrast enhancement (CE) varied by tumor type. On average, glioblastoma multiforme and medulloblastoma had uniform, intense uptake throughout the tumor, whereas brain stem gliomas (BSGs) had low uptake in less than 50% of the tumor and ependymoma had low uptake throughout the tumor. For newly diagnosed BSG, correlation of 18F-FDG uptake with CE portended reduced OS (P = 0.032); in refractory/recurrent BSG, lack of correlation between 18F-FDG uptake and CE suggested decreased PFS (P = 0.023). In newly diagnosed BSG for which more than 50% of the tumor had 18F-FDG uptake, there was a suggestion of lower apparent diffusion coefficient (P = 0.061) and decreased PFS (P = 0.065). Conclusion 18F-FDG PET and MR imaging showed a spectrum of patterns depending on tumor type. In newly diagnosed BSG, the correlation of 18F-FDG uptake and CE suggested decreased OS, likely related to more aggressive disease. When more than 50% of the tumor had 18F-FDG uptake, the apparent diffusion coefficient was lower, consistent with increased cellularity. In refractory/recurrent BSG, poor correlation between 18F-FDG

  4. Bitemporal hypometabolism in Creutzfeldt-Jakob Disease measured by positron emission tomography with (F-18)2-fluorodeoxyglucose

    SciTech Connect

    Friedland, R.P.; Budinger, T.F.; Prusiner, S.B.; Jagust, W.J.

    1984-01-01

    It is well established that Creutzfeldt-Jakob Disease (CJD) is caused by a slow infectious agent similar to the scrapie prion. However, the pathogenesis of this infection is poorly understood. Positron emission tomography (PET) was performed on a 54 year old male subject with autopsy confirmed CJD using (F-18)2-fluorodeoxyglucose (FDG) and the Donner 280-crystal tomograph. An x-ray computed tomographic study of the brain performed 4 days prior to PET was normal. In the PET study the frontal to temporal cortex difference of activity densities was 30% on the left and 12% on the right, reflecting temporal hypometabolism. The left-right temporal cortex difference of activity density was 25%, documenting marked hemispheric asymmetry. These findings are similar to those previously obtained in PET-FDG studies of patients with clinically defined Alzheimer's Disease (AD) and are distinctly different from PET-FDG finding in patients with other dementing illnesses or in healthy aged subjects. Recent work has demonstrated extensive biological similarities between CJD, scrapie and AD. The similarities in the regional metabolic alterations between CJD and AD provide additional evidence for the hypothesis that AD is caused by a slow infectious (prion-like) pathogen.

  5. F-18-fluorodeoxyglucose positron emission tomography-guided sampling of mediastinal lymph nodes in the diagnosis of cardiac sarcoidosis.

    PubMed

    Simonen, Piia; Lehtonen, Jukka; Kandolin, Riina; Schildt, Jukka; Marjasuo, Suvi; Miettinen, Heikki; Airaksinen, Juhani; Vihinen, Tapani; Tuohinen, Suvi; Haataja, Petri; Kupari, Markku

    2015-11-15

    Histologic proof of granulomatous inflammation is prerequisite for the diagnosis of cardiac sarcoidosis (CS). Because of the limited sensitivity of endomyocardial biopsy (EMB), confirmation of sarcoidosis often has to be acquired from extracardiac biopsies. We set out to review our experience of F-18-fluorodeoxyglucose positron emission tomography (F-18-FDG PET) in guiding extracardiac tissue biopsies in suspected CS. We included in this work 68 consecutive patients with proved CS who had undergone cardiac F-18-FDG PET with (n = 57) or without whole-body imaging as part of initial diagnostic evaluation. Their hospital charts, imaging studies, and diagnostic biopsies were reviewed in retrospect. Whole-body PET images showed extracardiac foci of abnormally high F-18-FDG uptake in 39 of 57 patients, of whom 38 had involvement of mediastinal lymph nodes (MLN). Parallel F-18-FDG uptake was found in other lymph nodes (n = 10), lungs (n = 9), liver (n = 3), spleen (n = 2), and thyroid gland (n = 1). Adding the mediastinal findings at cardiac PET without whole-body imaging, abnormal F-18-FDG uptake in MLN was found in totally 43 of the 68 patients with CS (63%). Histology of systemic sarcoidosis was known at presentation of cardiac symptoms in 8 patients. Of the 60 patients with missing histology, 24 patients underwent mediastinoscopy for sampling of PET-positive MLN, most often (n = 20) after nondiagnostic EMB; microscopy revealed diagnostic noncaseating granulomatous inflammation in 24 of the 24 cases (sensitivity 100%). In the remaining 36 patients, sarcoidosis histology was confirmed by EMB (n = 30), by biopsy of lungs (n = 2) or peripheral lymph nodes (n = 2), or at autopsy (n = 1) or post-transplantation (n = 1). In conclusion, MLN accumulate F-18-FDG at PET in most patients with CS and provide a highly productive source for diagnostic biopsies either primarily or subsequent to nondiagnostic EMB. PMID:26411357

  6. Human brain development in infants with PET and FDG

    SciTech Connect

    Phelps, M.E.; Chugani, H.T.

    1985-05-01

    The authors used studies of local cerebral metabolic rate for glucose (LCMRGlc) to examine development of cerebral organization in 5 days to 1 year old children. A group (n=8) of infants with diverse pediatric disorders allowed investigation of developmental changes in LCMRGlc, while also providing relevant clinical management information. Patients consisted of questionable and definite neonatal seizures, cerebral embolism from cardiac sources, and otherwise normal infants with facial nevi with consideration of Sturge-Weber. Gradual increase in cortical LCMRGlc coincides with suppression of intrinsic subcortical reflexes present in all newborns. Two retarded children (2 years old) showed LCMRGlc developmental patterns of a few days old, which corresponded to their functional and mental status. These studies illustrate great potential of PET to study normal and altered states of human brain development.

  7. Mild traumatic brain injury results in depressed cerebral glucose uptake: An (18)FDG PET study.

    PubMed

    Selwyn, Reed; Hockenbury, Nicole; Jaiswal, Shalini; Mathur, Sanjeev; Armstrong, Regina C; Byrnes, Kimberly R

    2013-12-01

    Moderate to severe traumatic brain injury (TBI) in humans and rats induces measurable metabolic changes, including a sustained depression in cerebral glucose uptake. However, the effect of a mild TBI on brain glucose uptake is unclear, particularly in rodent models. This study aimed to determine the glucose uptake pattern in the brain after a mild lateral fluid percussion (LFP) TBI. Briefly, adult male rats were subjected to a mild LFP and positron emission tomography (PET) imaging with (18)F-fluorodeoxyglucose ((18)FDG), which was performed prior to injury and at 3 and 24 h and 5, 9, and 16 days post-injury. Locomotor function was assessed prior to injury and at 1, 3, 7, 14, and 21 days after injury using modified beam walk tasks to confirm injury severity. Histology was performed at either 10 or 21 days post-injury. Analysis of function revealed a transient impairment in locomotor ability, which corresponds to a mild TBI. Using reference region normalization, PET imaging revealed that mild LFP-induced TBI depresses glucose uptake in both the ipsilateral and contralateral hemispheres in comparison with sham-injured and naïve controls from 3 h to 5 days post-injury. Further, areas of depressed glucose uptake were associated with regions of glial activation and axonal damage, but no measurable change in neuronal loss or gross tissue damage was observed. In conclusion, we show that mild TBI, which is characterized by transient impairments in function, axonal damage, and glial activation, results in an observable depression in overall brain glucose uptake using (18)FDG-PET. PMID:23829400

  8. 18F-FDG PET/CT Brain Imaging on a Patient With Paraneoplastic Opsoclonus-Myoclonus Syndrome Arising out of a Mature Cystic Teratoma.

    PubMed

    Na, Chang Ju; Jeong, Young Jin; Lim, Seok Tae; Sohn, Myung-Hee; Jeong, Hwan-Jeong

    2016-02-01

    Opsoclonus-myoclonus syndrome (OMS) is an involuntary multidirectional eye movement accompanied by myoclonic jerks and a subtype of paraneoplastic neurological syndromes. Clinical features of OMS include opsoclonus with myoclonic jerks and cerebellar ataxia. Although there have been a few studies on brain FDG PET in paraneoplastic neurological syndrome associated with some kinds of malignancies such as lung and gastric cancer, brain FDG PET of patients with OMS caused by a mature cystic teratoma has not been reported. Here, we described a case of brain FDG PET/CT studies performed in a woman with OMS provoked from a mature cystic teratoma.

  9. FDG-PET/CT Brain Findings in a Patient With Macrophagic Myofasciitis.

    PubMed

    Van Der Gucht, Axel; Aoun-Sebaiti, Mehdi; Kauv, Paul; Guedj, Eric; Aouizerate, Jessie; Verger, Antoine; Gherardi, Romain K; Bachoud-Levi, Anne-Catherine; Authier, François-Jérôme; Itti, Emmanuel

    2016-03-01

    Brain Positron Emission Tomography/Computed Tomography with (18)F-fluorodeoxyglucose (FDG PET/CT) was performed in a 44-year-old woman with marked cognitive impairment, diffuse myalgias, sensory, memory and visual disorders, and chronic fatigue, presenting with histopathological features of macrophagic myofasciitis (MMF) at deltoid muscle biopsy. Cerebromedullary Magnetic Resonance Imaging (MRI), electromyography, ophthalmic examination, and cerebrospinal fluid analysis were normal. Visual analysis of FDG PET/CT images showed an atypical pattern of hypometabolism, involving symmetrically the occipital cortex, temporal lobes, and limbic system (including in particular amygdalo-hippocampal complexes), and the cerebellum. Posterior cingulate cortex and parietal areas were preserved. This pattern was confirmed by a voxel-based procedure using Statistical Parametric Mapping (SPM12) that compared a patient's images to normal reference samples from six healthy subjects with adjustment to age obtained using the same PET/CT camera. These results provide a glucose metabolism substrate for cognitive complaints in patients with long-lasting aluminium hydroxide-induced MMF. PMID:26941864

  10. Preparation and biodistribution of F-18 labeled FQNPe

    SciTech Connect

    Luo, H.; Beets, K.; McPherson, D.W.; Knapp, F.F. Jr.

    1996-05-01

    1-Azabicyclo[2.2.2]oct-3-yl {alpha}-(1-fluoropentan-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetate (FQNPe) is an attractive candidate for the in vivo imaging of muscarinic receptors (mAChR) by PET. Initial studies with this new agent demonstrated a high binding affinity and ability to bind to regions of the brain containing mAChR. Fluorine-18 (F-18) labeling of racemic 1 was performed using X = tosyl, triflate, or mesylate group and a decay corrected radiolabeling yields of 2.6, 33, 75%, respectively, were obtained. F-18-3 in 11 % yield (decay corrected to beginning of synthesis). Initial biodistribution studies in rats (n=5) showed F-18-3 had high cerebral uptake of 0.72 ({plus_minus}0.26) and 0.83 ({plus_minus} 0.12) injected dose/gram at 15 and 30 minutes, respectively. The F-18 labeling and biodistribution study of the (-)-quinuclidinyl (-)-acetate and (-)-quinuclidinyl (+)-acetate isomers of FQNPe are currently being pursued.

  11. MicroPET/CT assessment of FDG uptake in brain after long-term methylphenidate treatment in nonhuman primates.

    PubMed

    Zhang, X; Newport, G D; Callicott, R; Liu, S; Thompson, J; Berridge, M S; Apana, S M; Slikker, W; Wang, C; Paule, M G

    2016-01-01

    Methylphenidate (MPH) is a psychostimulant commonly used for the treatment of Attention-Deficit Hyperactivity Disorder (ADHD). Since the long-term effects of this drug on the central nervous system (CNS) are not well understood, we conducted microPET/CT scans on young adult male rhesus monkeys (n=4/group) to gather information on brain metabolism using the uptake of [(18)F]Fluoro-2-deoxy-2-d-glucose (FDG) as a marker. Approximately two-year old, male rhesus monkeys were treated orally with MPH twice per day, five days per week (M-F) over a 6-year period. Subjects received MPH at either 2.5 or 12.5mg/kg/dose or vehicle (Prang). To minimize the acute effects of MPH on FDG uptake, microPET/CT scans were scheduled on Mondays before their first daily dosing of the week (approximately 68h since their last treatment). FDG (370±8.88MBq) was injected intravenously and 30min later microPET/CT images were obtained over 60min. Radiolabeled tracer accumulation in regions of interest (ROIs) in the prefrontal cortex, temporal cortex, striatum and cerebellum were converted into Standard Uptake Values (SUVs). Compared to the control group, the uptake of FDG in the cerebellum was significantly decreased in both the low and high dose groups. These preliminary data demonstrate that microPET imaging is capable of distinguishing differences in retention of FDG in the brains of NHPs treated chronically with MPH and suggests that this approach may provide a minimally invasive biomarker for exploring the effects of chronic MPH treatment on aspects of brain function. PMID:27307090

  12. MicroPET/CT assessment of FDG uptake in brain after long-term methylphenidate treatment in nonhuman primates.

    PubMed

    Zhang, X; Newport, G D; Callicott, R; Liu, S; Thompson, J; Berridge, M S; Apana, S M; Slikker, W; Wang, C; Paule, M G

    2016-01-01

    Methylphenidate (MPH) is a psychostimulant commonly used for the treatment of Attention-Deficit Hyperactivity Disorder (ADHD). Since the long-term effects of this drug on the central nervous system (CNS) are not well understood, we conducted microPET/CT scans on young adult male rhesus monkeys (n=4/group) to gather information on brain metabolism using the uptake of [(18)F]Fluoro-2-deoxy-2-d-glucose (FDG) as a marker. Approximately two-year old, male rhesus monkeys were treated orally with MPH twice per day, five days per week (M-F) over a 6-year period. Subjects received MPH at either 2.5 or 12.5mg/kg/dose or vehicle (Prang). To minimize the acute effects of MPH on FDG uptake, microPET/CT scans were scheduled on Mondays before their first daily dosing of the week (approximately 68h since their last treatment). FDG (370±8.88MBq) was injected intravenously and 30min later microPET/CT images were obtained over 60min. Radiolabeled tracer accumulation in regions of interest (ROIs) in the prefrontal cortex, temporal cortex, striatum and cerebellum were converted into Standard Uptake Values (SUVs). Compared to the control group, the uptake of FDG in the cerebellum was significantly decreased in both the low and high dose groups. These preliminary data demonstrate that microPET imaging is capable of distinguishing differences in retention of FDG in the brains of NHPs treated chronically with MPH and suggests that this approach may provide a minimally invasive biomarker for exploring the effects of chronic MPH treatment on aspects of brain function.

  13. Investigation of partial volume correction methods for brain FDG PET studies

    SciTech Connect

    Yang, J.; Huang, S.C.; Mega, M.; Toga, A.W.; Small, G.W.; Phelps, M.E.; Lin, K.P.

    1996-12-01

    The use of positron emission tomography (PET) in quantitative fluorodeoxyglucose (FDG) studies of aging and dementia has been limited by partial volume effects. A general method for correction of partial volume effects (PVE) in PET involves the following common procedures; segmentation of MRI brain images into gray matter (GM), white matter (WM), cerebral spinal fluid (CSF), and muscle (MS) components; MRI PET registration; and generation of simulated PET images. Afterward, two different approaches can be taken. The first approach derives first a pixel-by-pixel correction map as the ratio of the measured image to the simulated image [with realistic full-width at half-maximum (FWHM)]. The correction map was applied to the MRI segmentation image. Regions of interest (ROI`s) can then be applied to give results free of partial volume effects. The second approach uses the ROI values of the simulated ``pure`` image (with negligible FWHM) and those of the simulated and the measured PET images to correct for the PVE effect. By varying the ratio of radiotracer concentrations for different tissue components, the in-plane FWHM`s of a three-dimensional point spread function, and the ROI size, the authors evaluated the performance of these two approaches in terms of their accuracy and sensitivity to different simulation configurations. The results showed that both approaches are more robust than the approach developed by Muller-Gartner et al., and the second approach is more accurate and more robust than the first. In conclusion, the authors recommend that the second approach should be used on FDG PET images to correct for partial volume effects and to determine whether an apparent change in GM radiotracer concentration is truly due to metabolic changes.

  14. Factors affecting bilateral temporal lobe hypometabolism on 18F-FDG PET brain scan in unilateral medial temporal lobe epilepsy.

    PubMed

    Tepmongkol, Supatporn; Srikijvilaikul, Teeradej; Vasavid, Pataramon

    2013-11-01

    Bilateral temporal lobe hypometabolism (BTH) on (18)F-FDG PET brain scan is frequently seen in unilateral medial temporal lobe epilepsy (mTLE). This study aimed to identify the factors that influence BTH in patients with mTLE in order to minimize the significant factor(s) prior to performing a FDG-PET brain scan. Forty patients with unilateral mTLE who underwent (18)F-FDG PET scan for presurgical epilepsy workup were included. Bilateral temporal lobe hypometabolism of the anterior and medial parts of the temporal lobe was identified by a semiquantitative visual scale. Lateralization of TLE was identified by either intracranial EEG (22/40 cases) and/or improvement of seizure 2 years after temporal lobectomy (37/40 cases). The factors analyzed included basic demographic characteristics (age, sex, occupation, years of education, and handedness), history related to seizure (age at epilepsy onset and epilepsy duration, history of febrile seizure and head injury, frequency of seizure with impaired cognition in the last 3 months, presence of secondarily generalized tonic-clonic seizure, automatism side, presence of postictal confusion, and side of MRI temporal abnormality), information during video-EEG monitoring (clinical lateralization, interictal scalp EEG lateralization (interictal epileptiform discharge), and ictal scalp EEG lateralization), and information during the FDG-PET study (duration from the last seizure (≤2 days or >2 days), last seizure type, and the presence of slow waves or sharp waves during the FDG uptake period). Significant factors related to BTH were analyzed using multivariate analysis. Only the ≤2-day duration from the last seizure to the PET scan shows a significant effect (p=0.021) on BTH finding with 15 times greater incidence compared to a duration >2 days. Bilateral temporal lobe hypometabolism, which causes conflict in lateralizing the epileptogenic zone in temporal lobe epilepsy, can be avoided by performing PET scan more than 2 days

  15. Statistical parametric mapping and cluster counting analysis of [18F] FDG-PET imaging in traumatic brain injury.

    PubMed

    Zhang, Jing; Mitsis, Effie M; Chu, Kingwai; Newmark, Randall E; Hazlett, Erin A; Buchsbaum, Monte S

    2010-01-01

    In this study we investigated regional cerebral glucose metabolism abnormalities of [(18)F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging in traumatic brain injury (TBI). PET images of 81 TBI patients and 68 normal controls were acquired and a word list learning task was administered during the uptake period. The TBI group included 35 patients with positive structural imaging (CT or MRI) findings soon after injury, 40 patients with negative findings, and 6 cases without structural imaging. Statistical parametric mapping (SPM) analysis was applied with several levels of spatial smoothing. Cluster counting analysis was performed for each subject to identify abnormal clusters with contiguous voxel values that deviated by two standard deviations or more from the mean of the normal controls, and to count the number of clusters in 10 size categories. SPM maps demonstrated that the 81 patients had significantly lower FDG uptake than normal controls, widely across the cortex (including bilateral frontal and temporal regions), and in the thalamus. Cluster counting results indicated that TBI patients had a higher proportion of larger clusters than controls. These large low-FDG-uptake clusters of the TBI patients were closer to the brain edge than those of controls. These results suggest that deficits of cerebral metabolism in TBI are spread over multiple brain areas, that they are closer to the cortical surface than clusters in controls, and that group spatial patterns of abnormal cerebral metabolism may be similar in TBI patients with cognitive deficits with and without obvious acute abnormalities identified on structural imaging.

  16. Direct mapping of 19F in 19FDG-6P in brain tissue at subcellular resolution using soft X-ray fluorescence

    NASA Astrophysics Data System (ADS)

    Poitry-Yamate, C.; Gianoncelli, A.; Kourousias, G.; Kaulich, B.; Lepore, M.; Gruetter, R.; Kiskinova, M.

    2013-10-01

    Low energy x-ray fluorescence (LEXRF) detection was optimized for imaging cerebral glucose metabolism by mapping the fluorine LEXRF signal of 19F in 19FDG, trapped as intracellular 19F-deoxyglucose-6-phosphate (19FDG-6P) at 1μm spatial resolution from 3μm thick brain slices. 19FDG metabolism was evaluated in brain structures closely resembling the general cerebral cytoarchitecture following formalin fixation of brain slices and their inclusion in an epon matrix. 2-dimensional distribution maps of 19FDG-6P were placed in a cytoarchitectural and morphological context by simultaneous LEXRF mapping of N and O, and scanning transmission x-ray (STXM) imaging. A disproportionately high uptake and metabolism of glucose was found in neuropil relative to intracellular domains of the cell body of hypothalamic neurons, showing directly that neurons, like glial cells, also metabolize glucose. As 19F-deoxyglucose-6P is structurally identical to 18F-deoxyglucose-6P, LEXRF of subcellular 19F provides a link to in vivo 18FDG PET, forming a novel basis for understanding the physiological mechanisms underlying the 18FDG PET image, and the contribution of neurons and glia to the PET signal.

  17. Development and use of a kinetic FDG-PET dataset simulated from the MNI standard brain

    NASA Astrophysics Data System (ADS)

    Schottlander, David; Guimond, Alexandre; Pan, Xiao-Bo; Brady, Michael; Declerck, Jérôme; Collins, Louis; Evans, Alan C.; Reilhac, Anthonin

    2006-03-01

    Simulated data is an important tool for evaluation of reconstruction and image processing algorithms in the frequent absence of ground truth, in-vivo data from living subjects. This is especially true in the case of dynamic PET studies, in which counting statistics of the volume can vary widely over the time-course of the acquisition. Realistic simulated data-sets which model anatomy and physiology, and make explicit the spatial and temporal image acquisition characteristics, facilitate experimentation with a wide range of the conditions anticipated in practice, and which can severely challenge algorithm performance and reliability. As a first example, we have developed a realistic dynamic FDG-PET data-set using the PET-SORTEO Monte Carlo simulation code and the MNI digital brain phantom. The phantom is a three-dimensional data-set that defines the spatial distribution of different tissues. Time activity curves were calculated using an impulse response function specified by generally accepted rate constants, convolved with an input function obtained by blood sampling, and assigned to grey and white matter tissue regions. We created a dynamic PET study using PET-SORTEO configured to simulate an ECAT Exact HR+. The resulting sinograms were reconstructed with all corrections, using variations of FBP and OSEM. Having constructed the dynamic PET data-sets, we used them to evaluate the performance of intensity-based registration as part of a tool for quantifying hyper/hypo perfusion with particular application to analysis of brain dementia scans, and a study of the stability of kinetic parameter estimation.

  18. Early clinical PET imaging results with the novel PHF-tau radioligand [F-18]-T807.

    PubMed

    Chien, David T; Bahri, Shadfar; Szardenings, A Katrin; Walsh, Joseph C; Mu, Fanrong; Su, Min-Ying; Shankle, William R; Elizarov, Arkadij; Kolb, Hartmuth C

    2013-01-01

    Aggregates of hyperphosphorylated tau (PHF-tau), such as neurofibrillary tangles, are linked to the degree of cognitive impairment in Alzheimer's disease. We have developed a novel PHF-tau targeting positron emission tomography imaging agent, [F-18]-T807, which may be useful for imaging Alzheimer's disease and other tauopathies. Here in, we describe the first human brain images with [F-18]-T807.

  19. Identification of ischemic and hibernating myocardium: feasibility of post-exercise F-18 deoxyglucose positron emission tomography

    SciTech Connect

    Marwick, T.H.; MacIntyre, W.J.; Salcedo, E.E.; Go, R.T.; Saha, G.; Beachler, A. )

    1991-02-01

    The identification of ischemic and hibernating myocardium facilitates the selection of patients most likely to benefit from revascularization. This study examined the feasibility of metabolic imaging, using post-exercise F-18 deoxyglucose positron emission tomography (FDG-PET) for the diagnosis of both ischemia and hibernation in 27 patients with known coronary anatomy. Normal post-exercise FDG uptake was defined in each patient by reference to normal resting perfusion and normal coronary supply. Abnormal elevation of FDG (ischemia or hibernation) was compared in 13 myocardial segments in each patient, with the results of dipyridamole stress perfusion imaging performed by rubidium-82 positron emission tomography (Rb-PET). Myocardial ischemia was diagnosed by either FDG-PET or Rb-PET in 34 segments subtended by significant local coronary stenoses. Increased FDG uptake was present in 32/34 (94%) and a reversible perfusion defect was identified by Rb-PET in 22/34 (65%, p less than .01). In 3 patients, ischemia was identified by metabolic imaging alone. In 16 patients with previous myocardial infarction, perfusion defects were present at rest in 89 regions, 30 of which (34%) demonstrated increased FDG uptake, consistent with the presence of hibernation. Increased post-exercise FDG uptake appears to be a sensitive indicator of ischemia and myocardial hibernation. Increased post-exercise FDG uptake, appears to be a sensitive indicator of ischemia and myocardial hibernation. This test may be useful in selecting post-infarction patients for revascularization.

  20. F-18 SRA taxi at dawn

    NASA Technical Reports Server (NTRS)

    1993-01-01

    One of NASA's F/A-18 Hornets is seen here sitting on the ramp at the Dryden Flight Research Center, Edwards, California, at dawn August 6, 1993. F-18 aircraft, on loan to NASA by the U.S. Navy, are currently being flown at Dryden as support aircraft and as research testbeds. As support aircraft, they are used primarily for safety chase, pilot proficiency and aerial photography. As research aircraft, they are involved in thrust vectoring and high angle of attack research, as well as numerous smaller scale experiments.

  1. Tumor characteristics of ductal carcinoma in situ of breast visualized on [F-18] fluorodeoxyglucose-positron emission tomography/computed tomography: Results from a retrospective study

    PubMed Central

    Fujioka, Tomoyuki; Kubota, Kazunori; Toriihara, Akira; Machida, Youichi; Okazawa, Kaori; Nakagawa, Tsuyoshi; Saida, Yukihisa; Tateishi, Ukihide

    2016-01-01

    AIM To clarify clinicopathological features of ductal carcinoma in situ (DCIS) visualized on [F-18] fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT). METHODS This study retrospectively reviewed 52 consecutive tumors in 50 patients with pathologically proven pure DCIS who underwent [F-18] FDG-PET/CT before surgery. [F-18] FDG-PET/CT was performed after biopsy in all patients. The mean interval from biopsy to [F-18] FDG-PET/CT was 29.2 d. [F-18] FDG uptake by visual analysis and maximum standardized uptake value (SUVmax) was compared with clinicopathological characteristics. RESULTS [F-18] FDG uptake was visualized in 28 lesions (53.8%) and the mean and standard deviation of SUVmax was 1.63 and 0.90. On univariate analysis, visual analysis and the SUVmax were associated with symptomatic presentation (P = 0.012 and 0.002, respectively), palpability (P = 0.030 and 0.024, respectively), use of core-needle biopsy (CNB) (P = 0.023 and 0.012, respectively), ultrasound-guided biopsy (P = 0.040 and 0.006, respectively), enhancing lesion ≥ 20 mm on magnetic resonance imaging (MRI) (P = 0.001 and 0.010, respectively), tumor size ≥ 20 mm on histopathology (P = 0.002 and 0.008, respectively). However, [F-18] FDG uptake parameters were not significantly associated with age, presence of calcification on mammography, mass formation on MRI, presence of comedo necrosis, hormone status (estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2), and nuclear grade. The factors significantly associated with visual analysis and SUVmax were symptomatic presentation (P = 0.019 and 0.001, respectively), use of CNB (P = 0.001 and 0.031, respectively), and enhancing lesion ≥ 20 mm on MRI (P = 0.001 and 0.049, respectively) on multivariate analysis. CONCLUSION Although DCIS of breast is generally non-avid tumor, symptomatic and large tumors (≥ 20 mm) tend to be visualized on [F-18] FDG-PET/CT. PMID:27648168

  2. MRI-based elastic-mapping method for inter-subject comparison of brain FDG-PET images

    SciTech Connect

    Yang, J.; Huang, S.C.; Lin, K.P.; Small, G.; Phelps, M.E.

    1996-12-31

    Inter-subject anatomic differences prohibits direct image-wise statistical evaluation of brain FDG-PET images of Alzheimer`s disease (AD) patients. In this study, we propose a MRI-based elastic-mapping method which enables image-wise evaluation. The method involves intra-subject MR-PET registration, 3-D elastic mapping of two set of MR images, and elastically transforming the co-registered PET images. The MR-PET registration used simulated PET images, which were based on segmentation of MR images. In the 3-D elastic mapping stage, first a global linear scaling was applied to compensate for brain size difference, then a deformation field was obtained by minimizing the regional sum of squared difference between the two sets of MR images. Two groups (AD patient and normal control), each with three subjects, were included in the current study. After processing, images from all subjects have similar shapes. Averaging the images across all subjects (either within the individual group or for both groups) give images indistinguishable from original single subject FDG images (i.e. without much spatial resolution loss), except with lower image noise level. The method is expected to allow statistical image-wise analysis to be performed across different subjects.

  3. PET/CT imaging evidence of FUS-mediated (18)F-FDG uptake changes in rat brain

    PubMed Central

    Kim, Hyungmin; Park, Mi-Ae; Wang, Shuyan; Chiu, Alan; Fischer, Krisztina; Yoo, Seung-Schik

    2013-01-01

    Purpose: Transcranial focused ultrasound (FUS) delivers highly focused acoustic energy to a small region of the brain in a noninvasive manner. Recent studies have revealed that FUS, which is administered either in pulsed or continuous waves, can elicit or suppress neural tissue excitability. This neuromodulatory property of FUS has been demonstrated via direct motion detection, electrophysiological recordings, functional magnetic resonance imaging (fMRI), confocal imaging, and microdialysis sampling of neurotransmitters. This study presents new evidence of local increase in glucose metabolism induced by FUS to the rat brain using FDG (18-fludeoxyglucose) positron emission tomography (PET). Methods: Sprague–Dawley rats underwent sonication to a unilateral hemispheric area of the brain prior to PET scan. The pulsed sonication (350 kHz, tone burst duration of 0.5 ms, pulse repetition frequency of 1 kHz, and duration of 300 ms) was applied in 2 s intervals for 40 min immediately after the FDG injection via tail vein. Subsequently, the PET was acquired in dynamic list-mode to image FDG activity for an hour, and reconstructed into a single volume representing standardized uptake value (SUV). The raw SUV as well as its asymmetry index (AI) were measured from five different volume-of-interests (VOIs) of the brain for both hemispheres, and compared between sonicated and unsonicated groups. Results: Statistically significant hemispheric changes in SUV were observed only at the center of sonication focus within the FUS group [paired t-test; t(7) = 3.57, p < 0.05]. There were no significant hemispheric differences in SUV within the control group in any of the VOIs. A statistically significant elevation in AI (t-test; t(7) = 3.40, p < 0.05) was observed at the center of sonication focus (7.9 ± 2.5%, the deviations are in standard error) among the FUS group when compared to the control group (−0.8 ± 1.2%). Conclusions: Spatially distinct increases in the glucose metabolic

  4. Intelligent [F-18] fluoride target system

    NASA Astrophysics Data System (ADS)

    Hichwa, R. D.; Aykac, M.; Bilgen, D.; Watkins, G. L.

    1999-06-01

    An automated target filling system has been developed for [F-18]F- production from [O-18]water. The system consists of a pair of standard syringe dispensing pumps, valve manifolds, pressure and flow sensors, RS-232 serial I/O modules, high pressure silver targets and X-windows software. Operations are controlled through a graphical interface and can be manipulated individually, in groups for specific functions, or as complex processes either manually or automatically. Major functional operations include: 1) system test, 2) target fill, 3) target empty, and 4) target clean up. Fault conditions if present are identified and flagged. Alternate (duplicate) pathways are automatically used if a nonfatal failure mode is detected. Results from the testing procedures are logged to a file for documented adherence to SOPs and trend assessment of performance.

  5. Relationship between Tl-201, Tc-99m (Sn) pyrophosphate and F-18 2-deoxyglucose uptake in ischemically injured dog myocardium

    SciTech Connect

    Sochor, H.; Schwaiger, M.; Schelbert, H.R.; Huang, S.C.; Ellison, D.; Hansen, H.; Selin, C.; Parodi, O.; Phelps, M.E.

    1987-11-01

    We have previously demonstrated that enhanced glucose utilization in reperfused myocardium as assessed by F-18 2-deoxyglucose (FDG) and positron tomography predicts functional recovery. In this study, we compared segmental uptake of F-18 FDG with that of Tl-201 and Tc-99m (Sn) pyrophosphate (Tc-99m PPi) as conventional markers of tissue viability in seven dogs after a 3-hour intracoronary balloon occlusion and 20 hours of reperfusion. Myocardial blood flow was determined with microspheres. Regional retention fractions were calculated from tracer tissue concentrations, the arterial input function, and blood flow. Ischemic injury was assessed by triphenyltetrazolium chloride (TTC) staining and histologic analysis. At 24 hours, blood flow was 22% lower in reperfused than in control myocardium (p less than 0.05). Uptake of Tl-201 was related linearly to blood flow (r = 0.92), while glucose utilization and Tc-99m PPi were 2.9 (p less than 0.01) and 4.7 (p less than 0.05) times higher in reperfused than in control myocardium. Retention fractions of Tc-99m PPi increased with the degree of ischemic injury, while F-18 FDG uptake was highest in segments with mild cell injury. Thus, in ischemically injured myocardium, Tl-201 primarily reflects blood flow. F-18 FDG as a marker of glucose utilization identifies ischemically injured but viable tissue. The admixture of necrotic cells can be determined with Tc-99m PPi. Our results indicate that a dual tracer approach might best characterize the presence and extent of reversibly and of irreversibly injured tissue in a given myocardial region.

  6. Brain metastases detectability of routine whole body (18)F-FDG PET and low dose CT scanning in 2502 asymptomatic patients with solid extracranial tumors.

    PubMed

    Bochev, Pavel; Klisarova, Aneliya; Kaprelyan, Ara; Chaushev, Borislav; Dancheva, Zhivka

    2012-01-01

    As fluorine-18-fluorodesoxyglucose positron emission tomography/computed tomography ( (18)F-FDG PET/CT) is gaining wider availability, more and more patients with malignancies undergo whole body PET/CT, mostly to assess tumor spread in the rest of the body, but not in the brain. Brain is a common site of metastatic spread in patients with solid extracranial tumors. Gold standard in the diagnosis of brain metastases remains magnetic resonance imaging (MRI). However MRI is not routinely indicated and is not available for all cancer patients. Fluorine-18-FDG PET is considered as having poor sensitivity in detecting brain metastases, but this may not be true for PET/CT. The aim of our study was to assess the value of (18)F-FDG PET/CT in the detection of brain metastases found by whole body scan including the brain, in patients with solid extracranial neoplasms. A total of 2502 patients with solid extracranial neoplasms were studied. All patients underwent a routine whole body (18)F-FDG PET/CT scan with the whole brain included in the scanned field. Patients with known or suspected brain metastases were preliminary excluded from the study. Hypermetabolic and ring-like brain lesions on the PET scan were considered as metastases. Lesions with CT characteristics of brain metastases were regarded as such irrespective of their metabolic pattern. Lesions in doubt were verified by MRI during first testing or on follow-up or by operation. Our results showed that brain lesions, indicative of and verified to be metastases were detected in 25 out of the 2502 patients (1%), with lung cancer being the most common primary. Twenty three out of these 25 patients had no neurological symptoms by the time of the scan. The detection rate of brain metastases was relatively low, but information was obtained with a minimum increase of radiation burden. In conclusion, whole body (18)F-FDG PET/CT detected brain metastases in 1% of the patients if brain was included in the scanned field. Brain

  7. Hot-clot artifacts in the lung parenchyma on F-18 fluorodeoxyglucose positron emission tomography/CT due to faulty injection techniques: two case reports.

    PubMed

    Ozdemir, Elif; Poyraz, Nilufer Yildirim; Keskin, Mutlay; Kandemir, Zuhal; Turkolmez, Seyda

    2014-01-01

    F-18-fluorodeoxyglucose (FDG) positron emission tomography/CT is an important whole-body imaging tool in the oncology and widely utilized to stage and restage various malignancies. The findings of significant focal accumulation of FDG in the lung parenchyma in the absence of corresponding CT abnormalities are related to the lung microembolism and known as hot-clot artifacts. Herein we present two cases with focal FDG uptake in the lung parenchyma with no structural lesions on the CT scan and discuss the possible mechanisms.

  8. Effect of α-Methyl versus α-Hydrogen Substitution on Brain Availability and Tumor Imaging Properties of Heptanoic [F-18]Fluoroalkyl Amino Acids for Positron Emission Tomography (PET).

    PubMed

    Bouhlel, Ahlem; Alyami, Wadha; Li, Aixiao; Yuan, Liya; Rich, Keith; McConathy, Jonathan

    2016-04-14

    Two [(18)F]fluoroalkyl substituted amino acids differing only by the presence or absence of a methyl group on the α-carbon, (S)-2-amino-7-[(18)F]fluoro-2-methylheptanoic acid ((S)-[(18)F]FAMHep, (S)-[(18)F]14) and (S)-2-amino-7-[(18)F]fluoroheptanoic acid ((S)-[(18)F]FAHep, (S)-[(18)F]15), were developed for brain tumor imaging and compared to the well-established system L amino acid tracer, O-(2-[(18)F]fluoroethyl)-l-tyrosine ([(18)F]FET), in the delayed brain tumor (DBT) mouse model of high-grade glioma. Cell uptake, biodistribution, and PET/CT imaging studies showed differences in amino acid transport of these tracer by DBT cells. Recognition of (S)-[(18)F]15 but not (S)-[(18)F]14 by system L amino acid transporters led to approximately 8-10-fold higher uptake of the α-hydrogen substituted analogue (S)-[(18)F]15 in normal brain. (S)-[(18)F]15 had imaging properties similar to those of (S)-[(18)F]FET in the DBT tumor model while (S)-[(18)F]14 afforded higher tumor to brain ratios due to much lower uptake by normal brain. These results have important implications for the future development of α-alkyl and α,α-dialkyl substituted amino acids for brain tumor imaging.

  9. Statistical Voxel-Based Methods and [18F]FDG PET Brain Imaging: Frontiers for the Diagnosis of AD.

    PubMed

    Gallivanone, Francesca; Della Rosa, Pasquale Anthony; Castiglioni, Isabella

    2016-01-01

    Recommended guidelines for the diagnosis of dementia due to Alzheimer's Disease (AD) were revised in recent years, including Positron Emission Tomography (PET) as an in-vivo diagnostic imaging technique for the diagnosis of neurodegeneration. In particular PET, using 18Ffluorodeoxiglucouse ([18F]FDG), is able to detect very early changes of glucose consumption at the synaptic level, enabling to support both early and differential diagnosis of AD. In standard clinical practice, interpretation of [18F] FDG-PET images is usually achieved through qualitative assessment. Visual inspection although only reveals information visible at human eyes resolution, while information at a higher resolution is missed. Furthermore, qualitative assessment depends on the degree of expertise of the clinician, preventing from the definition of accurate and standardized imaging biomarkers. Automated and computerized image processing methods have been proposed to support the in-vivo assessment of brain PET studies. In particular, objective statistical image analyses, enabling the comparison of one patient's images to a group of control images have been shown to carry important advantages for detecting significant metabolic changes, including the availability of more objective, cross-center reliable metrics and the detectability of brain subtle functional changes, as occurring in prodromal AD. The purpose of the current review is to provide a systematic overview encompassing the frontiers recently reached by quantitative approaches for the statistical analysis of PET brain images in the study of AD, with a particular focus on Statistical Parametric Mapping. Main achievements, e.g. in terms of standardized biomarkers of AD as well as of sensitivity and specificity, will be discussed. PMID:26567733

  10. FDG-PET imaging in hematological malignancies.

    PubMed

    Valls, L; Badve, C; Avril, S; Herrmann, K; Faulhaber, P; O'Donnell, J; Avril, N

    2016-07-01

    The majority of aggressive lymphomas is characterized by an up regulated glycolytic activity, which enables the visualization by F-18 FDG-PET/CT. One-stop hybrid FDG-PET/CT combines the functional and morphologic information, outperforming both, CT and FDG-PET as separate imaging modalities. This has resulted in several recommendations using FDG-PET/CT for staging, restaging, monitoring during therapy, and assessment of treatment response as well as identification of malignant transformation. FDG-PET/CT may obviate the need for a bone marrow biopsy in patients with Hodgkin's lymphoma and diffuse large B cell lymphoma. FDG-PET/CT response assessment is recommended for FDG-avid lymphomas, whereas CT-based response evaluation remains important in lymphomas with low or variable FDG avidity. The treatment induced change in metabolic activity allows for assessment of response after completion of therapy as well as prediction of outcome early during therapy. The five-point scale Deauville Criteria allows the assessment of treatment response based on visual FDG-PET analysis. Although the use of FDG-PET/CT for prediction of therapeutic response is promising it should only be conducted in the context of clinical trials. Surveillance FDG-PET/CT after complete remission is discouraged due to the relative high number of false-positive findings, which in turn may result in further unnecessary investigations. Future directions include the use of new PET tracers such as F-18 fluorothymidine (FLT), a surrogate biomarker of cellular proliferation and Ga-68 CXCR4, a chemokine receptor imaging biomarker as well as innovative digital PET/CT and PET/MRI techniques. PMID:27090170

  11. Longitudinal Progression of Cognitive Decline Correlates with Changes in the Spatial Pattern of Brain 18F-FDG PET

    PubMed Central

    Shokouhi, Sepideh; Claassen, Daniel; Kang, Hakmook; Ding, Zhaohua; Rogers, Baxter; Mishra, Arabinda; Riddle, William R.

    2014-01-01

    Evaluating the symptomatic progression of mild cognitive impairment (MCI) caused by Alzheimer disease (AD) is practically accomplished by tracking performance on cognitive tasks, such as the Alzheimer Disease Assessment Scale’s cognitive subscale (ADAS_cog), the Mini-Mental Status Examination (MMSE), and the Functional Activities Questionnaire (FAQ). The longitudinal relationships between cognitive decline and metabolic function as assessed using 18F-FDG PET are needed to address both the cognitive and the biologic progression of disease state in individual subjects. We conducted an exploratory investigation to evaluate longitudinal changes in brain glucose metabolism of individual subjects and their relationship to the subject’s changes of cognitive status. Methods We describe a method to determine correlations in 18F-FDG spatial distribution over time. This parameter is termed the regional 18F-FDG time correlation coefficient (rFTC). By using linear mixed-effects models, we determined the difference in the rFTC decline rate between controls and subjects at high risk of developing AD, such as individuals with MCI or the presence of apolipoprotein E (APOE)–ε4 allele. The association between each subject’s rFTC and performance on cognitive tests (ADAS_cog, MMSE, and FAQ) was determined with 2 different correlation methods. All subject data were downloaded from the Alzheimer Disease Neuroimaging Initiative. Results The rFTC values of controls remained fairly constant over time (−0.003 annual change; 95% confidence interval, −0.010– 0.004). In MCI patients, the rFTC declined faster than in controls by an additional annual change of −0.02 (95% confidence interval, −0.030 to −0.010). In MCI patients, the decline in rFTC was associated with cognitive decline (ADAS_cog, P = 0.011; FAQ, P = 0.0016; MMSE, P = 0.004). After a linear effect of time was accounted for, visit-to-visit changes in rFTC correlated with visit-to-visit changes in all 3 cognitive

  12. Spectrum of neurocognitive dysfunction in Indian population on FDG PET/CT imaging

    PubMed Central

    Sharma, Rajnish; Tripathi, Madhavi; D’Souza, Maria M; Jaimini, Abhinav; Varshney, Raunak; Panwar, Puja; Kaushik, Aruna; Saw, Sanjeev; Seher, Romana; Pandey, Santosh; Singh, Dinesh; Solanki, Yachna; Mishra, Anil K; Mondal, Anupam; Tripathi, RP

    2011-01-01

    Background: A variety of neurodegenerative disorders produce significant abnormal brain function which can be detected using fluorodeoxyglucose positron emission tomography (FDG PET) scan even when structural changes are not detected on CT or MRI Scan. A study was undertaken at our institute to evaluate the FDG PET/CT findings in Indian population suffering from mild cognitive impairment (MCI), Alzheimer's disease (AD), fronto-temporal dementia (FTD), dementia with lewy body disease (DLBD) and other miscellaneous causes of dementia. Materials and Methods: 117 subjects having neurocognitive deficits and 36 normals were included in our study. All patients underwent a detailed history and clinical examination. This was followed by a mini mental state examination. Subsequently an FDG brain PET scan and an MRI were done. Results: In the patient population included in our study group 36 were normal, 39 had MCI, 40 had AD, 14 had FTD, and 13 had DLBD and 11 dementia due to other miscellaneous causes. MCI patients showed primarily reduced tracer uptake in the mesio-temporal cortex. AD patients showed reduced tracer concentration in temporo-parietal lobes, while patients with advanced diseases showed frontal lobe disease additionally. In subjects of FTD, reduced radiotracer uptake in the fronto-temporal lobes was noted. In addition, FTD patients also showed basal ganglia defects. In contrast the DLBD patients showed globally reduced FDG uptake including severely affecting the occipital cortices. Conclusion: In the current study the F18-FDG PET scans have been shown to be highly useful in the diagnosis of various neurocognitive disorders of the brain. AD was found to be the most common dementia in the Indian population followed by MCI. Diffuse Lewy body disease, FTD and other miscellaneous categories of dementia had a near similar incidence. PMID:22174510

  13. Reversal of brain metabolic abnormalities following treatment of AIDS dementia complex with 3'-azido-2',3'-dideoxythymidine (AZT, zidovudine): a PET-FDG study

    SciTech Connect

    Brunetti, A.; Berg, G.; Di Chiro, G.; Cohen, R.M.; Yarchoan, R.; Pizzo, P.A.; Broder, S.; Eddy, J.; Fulham, M.J.; Finn, R.D.

    1989-05-01

    Brain glucose metabolism was evaluated in four patients with acquired immunodeficiency syndrome (AIDS) dementia complex using (/sup 18/F)fluorodeoxyglucose (FDG) and positron emission tomography (PET) scans at the beginning of therapy with 3'-azido-2',3'-dideoxythymidine (AZT, zidovudine), and later in the course of therapy. In two patients, baseline, large focal cortical abnormalities of glucose utilization were reversed during the course of therapy. In the other two patients, the initial PET study did not reveal pronounced focal alterations, while the post-treatment scans showed markedly increased cortical glucose metabolism. The improved cortical glucose utilization was accompanied in all patients by immunologic and neurologic improvement. PET-FDG studies can detect cortical metabolic abnormalities associated with AIDS dementia complex, and may be used to monitor the metabolic improvement in response to AZT treatment.

  14. Brain metabolic changes in Hodgkin disease patients following diagnosis and during the disease course: An 18F-FDG PET/CT study

    PubMed Central

    CHIARAVALLOTI, AGOSTINO; PAGANI, MARCO; CANTONETTI, MARIA; DI PIETRO, BARBARA; TAVOLOZZA, MARIO; TRAVASCIO, LAURA; DI BIAGIO, DANIELE; DANIELI, ROBERTA; SCHILLACI, ORAZIO

    2015-01-01

    The aim of the present study was to investigate brain glucose metabolism in patients with Hodgkin disease (HD) after diagnosis and during chemotherapy treatment. Following the administration of first-line doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy, 74 HD patients underwent 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET)/computed tomography brain scans, both baseline (PET0) and interim (PET2) at the Department of Biomedicine and Prevention, University of Rome Tor Vergata (Rome, Italy). Fifty-seven patients were further evaluated 15±6 days after four additional cycles (PET6). Furthermore, a control group (CG) of 40 chemotherapy-naïve subjects was enrolled. Differences in brain 18F-FDG uptake between the CG, PET0, PET2 and PET6 scans were analyzed using statistical parametric mapping. Compared with the PET0 and CG scans, the PET2 scan demonstrated a higher metabolic activity in Brodmann area (BA) 39, and a metabolic reduction in BA 11 bilaterally and in left BA 32. All of these changes disappeared at PET6. The results of the present study indicate that ABVD chemotherapy has a limited impact on brain metabolism. PMID:25621038

  15. Insufficiency of Bone Scintigraphy in Vertebral Lesions of Langerhans Cell Histiocytosis Compared to F-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and Diagnostic Computed Tomography

    PubMed Central

    Koç, Zehra Pınar; Şimşek, Selçuk; Akarsu, Saadet; Balcı, Tansel Ansal; Onur, Mehmet Ruhi; Kepenek, Ferat

    2015-01-01

    Langerhans cell histiocytosis (LCH) is a benign disorder related to the histiocytes which can infiltrate bone tissue. The most effective method for demonstrating severity of this disease is PET/CT and bone scintigraphy might show bone lesions. We present a seventeen year old male patient with disseminated LCH presented with exophtalmos and having multiple vertebral lesions which were identified by F-18 FDG PET/CT scan and diagnostic CT but not in the bone scintigraphy. PMID:25800594

  16. Insufficiency of bone scintigraphy in vertebral lesions of langerhans cell histiocytosis compared to f-18 fluorodeoxyglucose positron emission tomography/computed tomography and diagnostic computed tomography.

    PubMed

    Koç, Zehra Pınar; Şimşek, Selçuk; Akarsu, Saadet; Balcı, Tansel Ansal; Onur, Mehmet Ruhi; Kepenek, Ferat

    2015-02-01

    Langerhans cell histiocytosis (LCH) is a benign disorder related to the histiocytes which can infiltrate bone tissue. The most effective method for demonstrating severity of this disease is PET/CT and bone scintigraphy might show bone lesions. We present a seventeen year old male patient with disseminated LCH presented with exophtalmos and having multiple vertebral lesions which were identified by F-18 FDG PET/CT scan and diagnostic CT but not in the bone scintigraphy.

  17. A quantitative analysis of the F18 flight control system

    NASA Technical Reports Server (NTRS)

    Doyle, Stacy A.; Dugan, Joanne B.; Patterson-Hine, Ann

    1993-01-01

    This paper presents an informal quantitative analysis of the F18 flight control system (FCS). The analysis technique combines a coverage model with a fault tree model. To demonstrate the method's extensive capabilities, we replace the fault tree with a digraph model of the F18 FCS, the only model available to us. The substitution shows that while digraphs have primarily been used for qualitative analysis, they can also be used for quantitative analysis. Based on our assumptions and the particular failure rates assigned to the F18 FCS components, we show that coverage does have a significant effect on the system's reliability and thus it is important to include coverage in the reliability analysis.

  18. [F-18]-(-,-)-FQNPe - an attractive ligand for evaluation of muscarinic-cholinergic neuron activity by PET

    SciTech Connect

    Luo, H.; McPherson, D.W.; Beets, A.L.; Knapp, F.F. Jr.

    1997-05-01

    The stereoisomers of 1-azabicyclo[2.2.2]oct-3-yl {alpha}-{alpha}-(1-fluoropentan-5-yl)-{alpha}-hydroxy-{alpha}-phenylacetate ({open_quotes}FQNPe{close_quotes}) have been resolved. (-,-)- receptors (K{sub i}, nM; ml, 0.3; m2, 0.1). [F-18]-(-,-)-FQNPe demonstrated high cerebral and myocardial uptake in rats in vivo. We now report significant blocking of [F-18]-(-.-)-FQNPe uptake in receptor-rich tissues in rats in vivo after (R)-QNB pretreatment and the absence of any TLC detectable FQNPe metabolites in tissue extracts. Rats were injected with (R)-QNB (3 mg/kg) 1 h prior to [F-18]-FQNPe injection (370-629 KBq). After 1 h, rats were sacrificed and tissues removed and counted. (R)-QNB significantly decreased FQNPe uptake in heart and all receptor-rich regions but not blood (Table; Mean % ID/g, n=5); C, control; Q, (R)-QNB; Hrt, heart; Cer, cerebellum; Pon, pons; Med, medulla; Cor, cortex; Stri, striatum; Hip, hippocampus; Th, thallamus; SuC, superior colliculi; InC, inferior colliculi. Tissues from untreated rats were Folch-extracted and 71-77% of activity was in organic extracts from brain and heart. TLC of organic extracts indicated a single radioactive component with R{sub f} of FQNPe. These combined results demonstrate that [F-18]-(-,-)-FQNPe does not appear to be metabolized in heart and brain, shows good receptor localization and is thus an attractive ligand for evaluation as a potential imaging agent by PET.

  19. Evaluation of cancer detection with whole-body positron emission tomography (PET) and 2-[F-18]fluoro-2-deoxy-D-glucose

    NASA Astrophysics Data System (ADS)

    Hoh, Carl K.; Hawkins, Randall A.; Glaspy, John A.; Dahlbom, Magnus; Tse, Nielson Y.; Hoffman, Edward T.; Schiepers, Christiaan; Choi, Yong; Rege, Sheila; Nitzsche, Egbert U.; Maddahi, Jamshid; Phelps, Michael E.

    1993-08-01

    Until recently, positron emission tomography (PET) has been acquired and displayed in a standard transaxial image format. The development of whole body PET has allowed biochemical and physiologic imaging of the entire body, expanding the limited axial field of view of the conventional PET scanner. In this study, the application of whole body PET studies with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG) for tumor imaging was evaluated. Whole body PET studies were positive (presence of focal FDG uptake relative to surrounding tissue activity) in 61 of 70 patients (87%) with biopsy confirmed malignant tumors. PET images failed to reveal focal hypermetabolism in 9 of the 70 patients. Of the 17 patients with benign biopsies lesions, 13 patients had whole body PET studies without focal areas of FDG uptake. Because of the high glycolytic rate of malignant tissue, the whole body PET FDG technique has promise in the detection of a wide variety of both primary and metastatic malignancies. The presence of FDG uptake in benign inflammatory conditions may limit the specificity of the technique. The true positive rates for the characterization of known lesions was 87% in this series, and the PET FDG method is promising both in determining both the nature of a localized lesion, and in defining the systemic extent of malignant disease.

  20. Two F-18s in Autonomous Formation Flight

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This 32 second video clip shows two F-18s in NASA's Autonomous Formation Flight (AFF) program. The aircraft use smoke contrails to gather data on wingtip vortices. Flight research attempts to utilize the energy in the vortices for more efficient flight.

  1. F-18 HARV With Nose Strakes For Forebody Vortex Control

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.

    1996-01-01

    Nose of F-18 High Alpha Research Vehicle (HARV) modified with conformal, mechanically actuated nose strakes for enhanced rolling (ANSER). Forebody vortex control effected by use of actuated strakes and/or other flow-control devices. System provides means to evaluate design tradeoffs.

  2. 76 FR 37129 - Determination That SODIUM FLUORIDE F 18 (Sodium Fluoride F-18) Injection, 10 to 200 Millicuries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... Product List'' section of the Orange Book. In previous instances (see, e.g., 72 FR 9763, March 5, 2007; 61 FR 25497, May 21, 1996), the Agency has determined that, for purposes of Sec. Sec. 314.161 and 314... HUMAN SERVICES Food and Drug Administration Determination That SODIUM FLUORIDE F 18 (Sodium Fluoride...

  3. Numerical investigation of tail buffet on F-18 aircraft

    NASA Technical Reports Server (NTRS)

    Rizk, Yehia M.; Guruswamy, Guru P.; Gee, Ken

    1992-01-01

    Numerical investigation of vortex induced tail buffet is conducted on the F-18 aircraft at high angles of attack. The Reynolds-averaged Navier-Stokes equations are integrated using a time-accurate, implicit procedure. A generalized overset zonal grid scheme is used to decompose the computational space around the complete aircraft with faired-over inlet. A weak coupling between the aerodynamics and structures is assumed to compute the structural oscillation of the flexible vertical tail. Time-accurate computations of the turbulent flow around the F-18 aircraft at 30 degrees angle of attack show the surface and off-surface flowfield details, including the unsteadiness created by the vortex burst and its interaction with the vertical twin tail which causes the tail buffet. The effect of installing a LEX fence on modifying the vortex structure upstream of the tail is also examined.

  4. A New F-18 Labeled PET Agent For Imaging Alzheimer's Plaques

    SciTech Connect

    Kulkarni, Padmakar V.; Hao Guiyang; Arora, Veera; Long, Michael; Slavine, Nikolai; Chiguru, Srinivas; Qu Baoxi; Sun Xiankai; Bennett, Michael; Antich, Peter P.; Bonte, Frederick J.; Vasdev, Neil

    2011-06-01

    Amyloid plaques and neurofibrillary tangles are hallmarks of Alzheimer's disease (AD). Advances in development of imaging agents have focused on targeting amyloid plaques. Notable success has been the development of C-11 labeled PIB (Pittsburgh Compound) and a number of studies have demonstrated the utility of this agent. However, the short half life of C-11 (t1/2: 20 min), is a limitation, thus has prompted the development of F-18 labeled agents. Most of these agents are derivatives of amyloid binding dyes; Congo red and Thioflavin. Some of these agents are in clinical trials with encouraging results. We have been exploring new class of agents based on 8-hydroxy quinoline, a weak metal chelator, targeting elevated levels of metals in plaques. Iodine-123 labeled clioquinol showed affinity for amyloid plaques however, it had limited brain uptake and was not successful in imaging in intact animals and humans. We have been successful in synthesizing F-18 labeled 8-hydroxy quinoline. Small animal PET/CT imaging studies with this agent showed high (7-10% ID/g), rapid brain uptake and fast washout of the agent from normal mice brains and delayed washout from transgenic Alzheimer's mice. These promising results encouraged us in further evaluation of this class of compounds for imaging AD plaques.

  5. Age- and Brain Region-Specific Changes of Glucose Metabolic Disorder, Learning, and Memory Dysfunction in Early Alzheimer’s Disease Assessed in APP/PS1 Transgenic Mice Using 18F-FDG-PET

    PubMed Central

    Li, Xue-Yuan; Men, Wei-Wei; Zhu, Hua; Lei, Jian-Feng; Zuo, Fu-Xing; Wang, Zhan-Jing; Zhu, Zhao-Hui; Bao, Xin-Jie; Wang, Ren-Zhi

    2016-01-01

    Alzheimer’s disease (AD) is a leading cause of dementia worldwide, associated with cognitive deficits and brain glucose metabolic alteration. However, the associations of glucose metabolic changes with cognitive dysfunction are less detailed. Here, we examined the brains of APP/presenilin 1 (PS1) transgenic (Tg) mice aged 2, 3.5, 5 and 8 months using 18F-labed fluorodeoxyglucose (18F-FDG) microPET to assess age- and brain region-specific changes of glucose metabolism. FDG uptake was calculated as a relative standardized uptake value (SUVr). Morris water maze (MWM) was used to evaluate learning and memory dysfunction. We showed a glucose utilization increase in multiple brain regions of Tg mice at 2 and 3.5 months but not at 5 and 8 months. Comparisons of SUVrs within brains showed higher glucose utilization than controls in the entorhinal cortex, hippocampus, and frontal cortex of Tg mice at 2 and 3.5 months but in the thalamus and striatum at 3.5, 5 and 8 months. By comparing SUVrs in the entorhinal cortex and hippocampus, Tg mice were distinguished from controls at 2 and 3.5 months. In MWM, Tg mice aged 2 months shared a similar performance to the controls (prodromal-AD). By contrast, Tg mice failed training tests at 3.5 months but failed all MWM tests at 5 and 8 months, suggestive of partial or complete cognitive deficits (symptomatic-AD). Correlation analyses showed that hippocampal SUVrs were significantly correlated with MWM parameters in the symptomatic-AD stage. These data suggest that glucose metabolic disorder occurs before onset of AD signs in APP/PS1 mice with the entorhinal cortex and hippocampus affected first, and that regional FDG uptake increase can be an early biomarker for AD. Furthermore, hippocampal FDG uptake is a possible indicator for progression of Alzheimer’s cognition after cognitive decline, at least in animals. PMID:27763550

  6. A voxel-based analysis of FDG-PET in traumatic brain injury: regional metabolism and relationship between the thalamus and cortical areas.

    PubMed

    García-Panach, Javier; Lull, Nuria; Lull, Juan José; Ferri, Joan; Martínez, Carlos; Sopena, Pablo; Robles, Montserrat; Chirivella, Javier; Noé, Enrique

    2011-09-01

    The objective was to study the correlations and the differences in glucose metabolism between the thalamus and cortical structures in a sample of severe traumatic brain injury (TBI) patients with different neurological outcomes. We studied 49 patients who had suffered a severe TBI and 10 healthy control subjects using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET). The patients were divided into three groups: a vegetative or minimally-conscious state (MCS&VS) group (n=17), which included patients who were in a vegetative or a minimally conscious state; an In-post-traumatic amnesia (In-PTA) group (n=12), which included patients in PTA; and an Out-PTA group (n=20), which included patients who had recovered from PTA. SPM5 software was used to determine the metabolic differences between the groups. FDG-PET images were normalized and four regions of interest were generated around the thalamus, precuneus, and the frontal and temporal lobes. The groups were parameterized using Student's t-test. Principal component analysis was used to obtain an intensity-estimated-value per subject to correlate the function between the structures. Differences in glucose metabolism in all structures were related to the neurological outcome, and the most severe patients showed the most severe hypometabolism. We also found a significant correlation between the cortico-thalamo-cortical metabolism in all groups. Voxel-based analysis suggests a functional correlation between these four areas, and decreased metabolism was associated with less favorable outcomes. Higher levels of activation of the cortico-cortical connections appear to be related to better neurological condition. Differences in the thalamo-cortical correlations between patients and controls may be related to traumatic dysfunction due to focal or diffuse lesions. PMID:21770759

  7. F-18 HARV in flight with actuated nose strakes

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA's F-18 from the Dryden Flight Research Center, Edwards, California, soars over the Mojave Desert while flying the current phase of the HARV (High Alpha Research Vehicle) program. A set of control surfaces called strakes were installed in the nose of the aircraft. The strakes, outlined in gold and white, provided improved yaw control at steep angles of attack. Normally folded flush, the units -- four feet long and six inches wide -- can be opened independently to interact with the nose vortices to produce large side forces for control. Testing involved evaluation of the strakes by themselves as well as combined with the aircraft's Thrust Vectoring System. The strakes were designed by NASA's Langley Research Center, then installed and flight tested at Dryden.

  8. F-18 HARV in flight with actuated nose strakes

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA's F-18 from the Dryden Flight Research Center, Edwards, California, soars over the Mojave Desert while flying the third and final phase of the HARV (High Alpha Research Vehicle) program. A set of control surfaces called strakes were installed in the nose of the aircraft. The strakes, outlined in gold and white, provided improved yaw control at steep angles of attack. Normally folded flush, the units -- four feet long and six inches wide -- can be opened independently to interact with the nose vortices to produce large side forces for control. Testing involved evaluation of the strakes by themselves as well as combined with the aircraft's Thrust Vectoring System. The strakes were designed by NASA's Langley Research Center, then installed and flight tested at Dryden.

  9. [F-18]-Fluoro-2-deoxy-D-glucose positron emission tomography as a tool for early detection of immunotherapy response in a murine B cell lymphoma model

    PubMed Central

    Chaise, Coralie; Itti, Emmanuel; Petegnief, Yolande; Wirquin, Evelyne; Copie-Bergman, Christiane; Farcet, Jean-Pierre; Delfau-Larue, Marie-Hélène; Meignan, Michel; Talbot, Jean-Noël; Molinier-Frenkel, Valérie

    2007-01-01

    [F-18]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is a non-invasive imaging technique which has recently been validated for the assessment of therapy response in patients with aggressive non-Hodgkin’s lymphoma. Our objective was to determine its value for the evaluation of immunotherapy efficacy in immunocompetent Balb/c mice injected with the A20 syngeneic B lymphoma cell line. The high level of in vitro FDG uptake by A20 cells validated the model for further imaging studies. When injected intravenously, the tumour developed as nodular lesions mostly in liver and spleen, thus mimicking the natural course of an aggressive human lymphoma. FDG-PET provided three-dimensionnal images of tumour extension including non palpable lesions, in good correlation with ex-vivo macroscopic examination. When mice were pre-immunized with an A20 cell lysate in adjuvant before tumour challenge, their significantly longer survival, compared to control mice, was associated with a lower incidence of lymphoma visualized by PET at different time points. Estimation of tumour growth and metabolism using the calculated tumour volumes and maximum standardized uptake values respectively, also demonstrated delayed lymphoma development and lower activity in the vaccinated mice. Thus, FDG-PET is a sensitive tool relevant for early detection and follow-up of internal tumours, allowing discrimination between treated and non-treated small animal cohorts without invasive intervention. PMID:17171356

  10. Is cerebral glucose metabolism related to blood-brain barrier dysfunction and intrathecal IgG synthesis in Alzheimer disease?: A 18F-FDG PET/CT study.

    PubMed

    Chiaravalloti, Agostino; Fiorentini, Alessandro; Francesco, Ursini; Martorana, Alessandro; Koch, Giacomo; Belli, Lorena; Torniolo, Sofia; Di Pietro, Barbara; Motta, Caterina; Schillaci, Orazio

    2016-09-01

    The aim of this study was to investigate the relationships between blood-brain barrier (BBB) dysfunction, intrathecal IgG synthesis, and brain glucose consumption as detectable by means of serum/cerebrospinal fluid (CSF) albumin index (Qalb) and IgG index [(CSF IgG/serum IgG) × Serum albumin/CSF albumin)] and 2-deoxy-2-(F) fluoro-D-glucose (F-FDG) positron emission tomography/computed tomography (PET/CT) in a selected population affected by Alzheimer disease (AD). The study included 134 newly diagnosed AD patients according to the NINCDS-ADRDA criteria. The mean (±SD) age of the patients was 70 (±6) years; 60 were male and 64 were female. Mini mental State Examination was equal to 18.9 (±7.2). All patients underwent a CSF assay and magnetic resonance before F-FDG PET scanning. The relationships were evaluated by means of statistical parametric mapping (SPM8). We found a significant negative correlation between the increase of Qalb and F-FDG uptake in the Brodmann Area 42 and 22 that corresponds to the left superior temporal gyrus, with higher Qalb values being related to a reduced glucose consumption in these areas. No significant relationships have been found between brain glucose consumption and IgG index. The results of our study suggest that BBB dysfunction is related to reduction of cortical activity in the left temporal cortex in AD subjects. PMID:27631200

  11. Preclinical testing of F-18 and I-123 radioligands involving autoradiography and a phosphor-imaging device

    SciTech Connect

    Gatley, S.J.; Pyatt, B.; Gifford, A.N.

    1997-05-01

    During the development and validation of a receptor-binding radiopharmaceutical it is necessary to assess its brain regional distribution. Film contact autoradiography (AR) points such distributions to be evaluated on a fine anatomical scale, and avoids the inherent risk a microdissection experiments of missing interesting localization pattern. However, in vivo film AR may require a 1000-fold higher activity of a F-18 or I-123 radioligand than microdissection. In addition to health physics considerations, problems with receptor saturation can easily occur after injecting, say, 10 mCi into a 250g rat. A less commonly appreciated problem even with in vitro AR, using slide-mounted brain sections, is that it may be impossible to use sufficient F-18 to obtain acceptable images using film, because of receptor saturation. Phosphorimaging is superior in sensitivity to film by a factor of 10-50, and so relaxes constraints on injected activities and specific activities. Furthermore, it is also superior to film in terms of dynamic range and linearity of response. We have recently used phosphorimaging in two situations where film AR gave unsatisfactory results. (1) the novel cannabinoid CB1 receptor radioligand, I-123 AM281, was injected intravenously at 800 microcurie per rat. Animals were sacrificed at 2 h, frozen and whole body sections prepared. I-123 was clearly visualized in discrete brain areas (substantia nigra, globus pallidus, entopeduncular nucleus , hippocampus and cerebellum) consistent with the distribution of CB1 receptors previously demonstrated only in in vitro studies. (2) Rat brain sections were thaw mounted on gelatin/alum coated glass and incubated with the novel nicotinic acetylcholine receptor ligand F-18 2{prime}-fluoro-2{prime} nor-chloroepibatidine (1 nM).

  12. Test-retest reproducibility for regional brain metabolic responses to lorazepam

    SciTech Connect

    Wang, G.J.; Volkow, N.D.; Overall, J. |||

    1996-05-01

    Changes in regional brain glucose metabolism as assessed with PET and FDG in response to acute administration of benzodiazepine agonists have been used as indicators of benzodiazepine-GABA receptor function. The purpose of this study was to assess the reproducibility of these responses. Sixteen healthy right-handed men were scanned with positron emission tomography (PET) and [F-18] fluorodeoxyglucose (FDG) twice: prior to placebo and prior to lorazepam (30 {mu}g/kg). The same double FDG procedure was repeated 6-8 weeks later to assess test-retest reproducibility. The regional absolute brain metabolic values obtained during the second evaluation were significantly lower than those obtained for the first evaluation regardless of condition (p {le} 0.001). Lorazepam significantly and consistently decreased whole brain metabolism and the magnitude as well as the regional pattern of the changes was comparable for both studies (12.3 {plus_minus} 6.9% and 13.7 {plus_minus} 7.4%). Lorazepam effects were largest in thalamus (22.2 {plus_minus} 8.9%). Relative metabolic measures ROI/global were highly reproducible both for drug as well as replication condition. This is the first study to measure test-retest reproducibility in regional brain metabolic response to a pharmacological challenge. While the global and regional absolute metabolic values were significantly lower for the repeated evaluation, the regional brain metabolic response to lorazepam was highly reproducible.

  13. Proteomic Analysis of Duodenal Tissue from Escherichia coli F18-Resistant and -Susceptible Weaned Piglets

    PubMed Central

    Wu, Zhengchang; Xia, Riwei; Yin, Xuemei; Huo, Yongjiu; Zhu, Guoqiang; Wu, Shenglong; Bao, Wenbin

    2015-01-01

    Diarrhea and edema disease in weaned piglets due to infection by Escherichia coli F18 is a leading cause of economic loss in the pig industry. Resistance to E. coli F18 depends on expression of receptors on intestinal epithelial cells, and individual immunity. This study was conducted in Sutai pig E. coli F18-resistant and -susceptible full sib-pair individuals, identified on the basis of resource populations and verification of adhesion assays. The molecular mechanism underlying E. coli F18 resistance was investigated through analysis of the expression of E. coli F18 receptor associated and innate immunity proteins, using proteomics and bioinformatics techniques. Two-dimensional electrophoresis analysis revealed a total of 20 differentially expressed proteins in E. coli F18-resistant and -susceptible groups (10 upregulated and 10 downregulated). A total of 16 differentially expressed proteins were identified by MALDI TOF/TOF mass spectral analysis. According to gene ontology and pathway analysis, differentially expressed proteins were mainly involved in cell adhesion, immune response and other biologically relevant functions. Network analysis of interactions between differentially expressed proteins indicated a likelihood of their involvement in E. coli F18 infection. The expression levels of several important proteins including actin beta (ACTB), vinculin (VCL), heat stress proteins (HSPs) and transferrin (TF) in E. coli F18-resistant and -susceptible individuals were verified by Western blotting, supporting the identification of ACTB, VCL, HSPs and TF as promising candidate proteins for association with E. coli F18 susceptibility. PMID:26053838

  14. F-18 Fluorodeoxyglucose Positron Emission Tomography study of Impaired Emotion Processing in First Episode Schizophrenia

    PubMed Central

    Choudhary, Mona; Kumar, Arvind; Tripathi, Madhavi; Bhatia, Triptish; Shivakumar, Venkataram; Beniwal, Ram Pratap; Gur, Ruben C.; Gur, Raquel E.; Nimgaonkar, Vishwajit L.

    2015-01-01

    Background Schizophrenia cases have consistently shown to have behavioural and neurofunctional abnormalities but studies during early course are scarce. The present work assesses the performance of acute first episode schizophrenia cases on correlation of a facial emotion perception task with brain function using Fluorine-18 Fluorodeoxyglucose (FDG) positron emission tomography (PET). Methods Twenty First episode schizophrenia cases and 20 matched healthy controls living in the community were enrolled. For cases, longest duration of illness was one year and treatment with neuroleptic did not exceed two weeks on the day of scan. To measure facial emotion perception (FEP) both groups were administered the Emotion battery from the Penn Computerized Battery followed by PET acquisition. SPM 8 analysis for group differences at p<0.001 was performed. Results Schizophrenia subjects showed hypoactivation of bilateral prefrontal cortices and fusiform gyrii, with significant hyperactivation of bilateral basal ganglia and left precuneus. Positive correlation of metabolism in prefrontal cortex and performance indices on emotions domain was seen. No correlation of CPZ equivalent days with metabolism in basal ganglia was observed. Conclusions The performance of schizophrenia cases on FEP task was significantly impaired in comparison to the control group. Brain regions implicated in emotion processing showed hypometabolism in cases as compared to controls. Failure of schizophrenia cases to optimally recruit brain circuitry may be contributing to deficits on FEP task. These findings suggest inherent deficits in neural circuitry of emotion processing in schizophrenia; devoid of confounding effects of neuroleptics and duration of illness. PMID:25655909

  15. Quantitative characterization of brain β-amyloid in 718 normal subjects using a joint PiB/FDG PET image histogram

    NASA Astrophysics Data System (ADS)

    Camp, Jon J.; Hanson, Dennis P.; Lowe, Val J.; Kemp, Bradley J.; Senjem, Matthew L.; Murray, Melissa E.; Dickson, Dennis W.; Parisi, Joseph E.; Petersen, Ronald C.; Robb, Richard A.; Holmes, David R.

    2016-03-01

    We have previously described an automated system for the co-registration of PiB and FDG PET images with structural MRI and a neurological anatomy atlas to produce region-specific quantization of cortical activity and amyloid burden. We also reported a global joint PiB/FDG histogram-based measure (FDG-Associated PiB Uptake Ratio - FAPUR) that performed as well as regional PiB ratio in stratifying Alzheimer's disease (AD) and Lewy Body Dementia (LBD) patients from normal subjects in an autopsy-verified cohort of 31. In this paper we examine results of this analysis on a clinically-verified cohort of 718 normal volunteers. We found that the global FDG ratio correlated negatively with age (r2 = 0.044) and global PiB ratio correlated positively with age (r2=0.038). FAPUR also correlated negatively with age (r2-.025), and in addition, we introduce a new metric - the Pearson's correlation coefficient (r2) of the joint PiB/FDG histogram which correlates positively (r2=0.014) with age. We then used these measurements to construct age-weighted Z-scores for all measurements made on the original autopsy cohort. We found similar stratification using Z-scores compared to raw values; however, the joint PiB/FDG r2 Z-score showed the greatest stratification ability.

  16. X-31 in Flight with F-18 Chase

    NASA Technical Reports Server (NTRS)

    1994-01-01

    One of two X-31 Enhanced Fighter Maneuverability Demonstrator aircraft (top), flown by an international test organization at NASA's Dryden Flight Research Center, Edwards, California, is seen here accompanied by a NASA F-18 chase aircraft during a research flight over the desert floor. The X-31 had a three-axis thrust-vectoring system, coupled with advanced flight controls, to allow it to maneuver tightly at very high angles of attack. The X-31 Enhanced Fighter Maneuverability (EFM) demonstrator flew at the Ames- Dryden Flight Research Facility, Edwards, California (redesignated the Dryden Flight Research Center in 1994) from February 1992 until 1995 and before that at the Air Force's Plant 42 in Palmdale, California. The goal of the project was to provide design information for the next generation of highly maneuverable fighter aircraft. This program demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with an advanced flight control system to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in close-in combat situations. The X-31 flight program focused on agile flight within the post-stall regime, producing technical data to give aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. Stall is a condition of an airplane or an airfoil in which lift decreases and drag increases due to the separation of airflow. Thrust vectoring compensates for the loss of control through normal aerodynamic surfaces that occurs during a stall. Post-stall refers to flying beyond the normal stall angle of attack, which in the X-31 was at a 30-degree angle of attack. During Dryden flight testing, the X-31 aircraft established several milestones. On November 6, 1992, the X-31 achieved controlled flight at a 70-degree angle of attack. On April 29, 1993, the second X-31

  17. X-31 in Flight with F-18 Chase

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A head-on view of the X-31 Enhanced Fighter Maneuverability Demonstrator aircraft (right), accompanied by a NASA F-18 chase aircraft during a research flight over the desert floor. The X-31 had a three-axis thrust-vectoring system, coupled with advanced flight controls, to allow it to maneuver tightly at very high angles of attack. The X-31 Enhanced Fighter Maneuverability (EFM) demonstrator flew at the Ames- Dryden Flight Research Facility, Edwards, California (redesignated the Dryden Flight Research Center in 1994) from February 1992 until 1995 and before that at the Air Force's Plant 42 in Palmdale, California. The goal of the project was to provide design information for the next generation of highly maneuverable fighter aircraft. This program demonstrated the value of using thrust vectoring (directing engine exhaust flow) coupled with an advanced flight control system to provide controlled flight to very high angles of attack. The result was a significant advantage over most conventional fighters in close-in combat situations. The X-31 flight program focused on agile flight within the post-stall regime, producing technical data to give aircraft designers a better understanding of aerodynamics, effectiveness of flight controls and thrust vectoring, and airflow phenomena at high angles of attack. Stall is a condition of an airplane or an airfoil in which lift decreases and drag increases due to the separation of airflow. Thrust vectoring compensates for the loss of control through normal aerodynamic surfaces that occurs during a stall. Post-stall refers to flying beyond the normal stall angle of attack, which in the X-31 was at a 30-degree angle of attack. During Dryden flight testing, the X-31 aircraft established several milestones. On November 6, 1992, the X-31 achieved controlled flight at a 70-degree angle of attack. On April 29, 1993, the second X-31 successfully executed a rapid minimum-radius, 180-degree turn using a post-stall maneuver, flying well

  18. Brain glucose metabolism is associated with hormone level in Cushing's disease: A voxel-based study using FDG-PET.

    PubMed

    Liu, Shuai; Wang, Yinyan; Xu, Kaibin; Ping, Fan; Wang, Renzhi; Li, Fang; Cheng, Xin

    2016-01-01

    Chronic exposure to elevated levels of glucocorticoids can exert a neurotoxic effect in patients, possibly manifesting as molecular imaging alterations in patients. The aim of this study was to investigate the potential association between brain metabolism and elevated hormone level using (18)F-fluorodeoxyglucose positron emission tomography. We retrospectively enrolled 92 consecutive patients with confirmed diagnosis of Cushing's disease. A voxel-based analysis was performed to investigate the association between cerebral (18)F-fluorodeoxyglucose uptake and serum cortisol level. Relatively impaired metabolism of specific brain regions correlated with serum cortisol level was found. Specifically, notable correlations were found in the hippocampus, amygdala, and cerebellum, regions considered to be involved in the regulation and central action of glucocorticoids. Moreover, some hormone-associated regions were found in the frontal and occipital cortex, possibly mediating the cognitive changes seen in Cushing's disease. Our findings link patterns of perturbed brain metabolism relates to individual hormone level, thus presenting a substrate for cognitive disturbances seen in Cushing's disease patients, as well as in other conditions with abnormal cortisol levels.

  19. Brain glucose metabolism is associated with hormone level in Cushing's disease: A voxel-based study using FDG-PET.

    PubMed

    Liu, Shuai; Wang, Yinyan; Xu, Kaibin; Ping, Fan; Wang, Renzhi; Li, Fang; Cheng, Xin

    2016-01-01

    Chronic exposure to elevated levels of glucocorticoids can exert a neurotoxic effect in patients, possibly manifesting as molecular imaging alterations in patients. The aim of this study was to investigate the potential association between brain metabolism and elevated hormone level using (18)F-fluorodeoxyglucose positron emission tomography. We retrospectively enrolled 92 consecutive patients with confirmed diagnosis of Cushing's disease. A voxel-based analysis was performed to investigate the association between cerebral (18)F-fluorodeoxyglucose uptake and serum cortisol level. Relatively impaired metabolism of specific brain regions correlated with serum cortisol level was found. Specifically, notable correlations were found in the hippocampus, amygdala, and cerebellum, regions considered to be involved in the regulation and central action of glucocorticoids. Moreover, some hormone-associated regions were found in the frontal and occipital cortex, possibly mediating the cognitive changes seen in Cushing's disease. Our findings link patterns of perturbed brain metabolism relates to individual hormone level, thus presenting a substrate for cognitive disturbances seen in Cushing's disease patients, as well as in other conditions with abnormal cortisol levels. PMID:27622138

  20. Radiosynthesis of F-18-3-acetylcyclofoxy: A high affinity opiate antagonist

    SciTech Connect

    Channing, M.A.; Eckelman, W.C.; Bennett, J.M.; Burke, T.R. Jr.; Rice, K.C.; Larson, S.M.

    1985-05-01

    A convenient method for the preparation of F-18-3-acetylcyclofoxy (3-acetyl-6-deoxy-6-beta-F-18-fluoronaltrexone was developed. The method uses reactor-produced F-18-fluoride as its tetraethylammonium salt. F-18 fluoride is produced at the National Bureau of Standards nuclear reactor by the Li-6(n,..cap alpha..)H-3, 0-16(H-3,n) F-18 nuclear reaction. A sealed quartz tube containing enriched lithium carbonate (0.4 g) was irradiated in a neutron flux of 1.1 x 10/sup 14/ n/cm/sup 2//s for 2h to produce 80 mCi. The lithium is removed by cation exchange resin. The fluoride is then adsorbed on a strong anion exchange column which is rinsed to remove H-3 and any remaining cations. The F-18 is then eluted with tetraethylammonium hydroxide to produce tetraethylammonium fluoride (TEAF). The triflate of 3-acetyl-6-alpha-naltrexol, synthesized by reaction of the alcohol with trifluoromethanesulfonic anhydride was added in anhydrous acetonitrile to the dry F-18 TEAF containing 0.2 ..mu..mol F-19 TEAF. The mixture was refluxed for 15 minutes after which the product was purified by reversed phase chromatography. F-18-acetylcyclofoxy was prepared in 35% radiochemical yield. About 55% of the F-18 was lost by decay (36%) and by incomplete transfer (19%). The specific activity of the final product was approximately 50 Ci/mmol but the effective specific activity was approximately 25 Ci/mmol. Visualization of the basal ganglia in baboons was possible using PET. F-18 3-acetylcyclofoxy is the first positron-emitting opiate for which the active and inactive forms of naloxone were used to unequivocially demonstrate stereospecific displacement from opiate receptor-rich regions.

  1. Choice of reference area in studies of Alzheimer's disease using positron emission tomography with fluorodeoxyglucose-F18.

    PubMed

    Yakushev, Igor; Landvogt, Christian; Buchholz, Hans-Georg; Fellgiebel, Andreas; Hammers, Alexander; Scheurich, Armin; Schmidtmann, Irene; Gerhard, Alexander; Schreckenberger, Mathias; Bartenstein, Peter

    2008-11-30

    At present, there is still no consensus on the choice of the reference area in positron emission tomography (PET) studies of Alzheimer's disease (AD). In this study, PET scans with fluorodeoxyglucose-F18 were carried out in the following groups of subjects: 47 patients with probable AD, 8 patients with mild cognitive impairment, and 15 age-similar healthy subjects. Scans normalized to the cerebral global mean (CGM), cerebellum (CBL), and the primary sensorimotor cortex (SMC). We evaluated the effect of the different count normalization procedures on the accuracy of (18)F-FDG PET to detect AD-specific metabolic abnormalities (voxel-based group comparison) and to differentiate between patients and healthy subjects (ROI-based discriminant analysis) with regard to the degree of clinical deterioration. Metabolic reductions in groups of very mildly, mildly and moderate-to-severely affected patients appeared, respectively, 2.2, 2.6, and 2.7 times greater in spatial extent when tracer uptake was normalized to SMC rather than to CGM. The overall accuracy of discrimination was 94%, 91%, and 80% after normalization to SMC, CBL, and CGM, respectively. In general, normalization to SMC was somewhat superior to cerebellar normalization, allowing the detection of more pronounced metabolic deficits and the more accurate discrimination of patients from non-patients. Normalization to CGM should be used with great caution not only in advanced stages of dementia, but also in very mild AD cases. PMID:18930634

  2. Defining PET / CT Protocols With Optimized F18-FDG (Fluorodeoxyglucose) Dose, Focusing on Reduced Radiation Dose and Improved Image Quality

    ClinicalTrials.gov

    2015-08-19

    Malignant Neoplasm of Breast.; Hodgkin's Disease.; Non-Hodgkin Lymphoma, Follicular (Nodular).; Malignant Neoplasm of Bronchus and Lung.; Malignant Neoplasm of Colon.; Secondary Neoplasm Malignant and Unspecified Lymph Nodes.; Malignant Melanoma of the Skin.; Malignant Neoplasm of Small Intestine.

  3. Local activity determines functional connectivity in the resting human brain: a simultaneous FDG-PET/fMRI study.

    PubMed

    Riedl, Valentin; Bienkowska, Katarzyna; Strobel, Carola; Tahmasian, Masoud; Grimmer, Timo; Förster, Stefan; Friston, Karl J; Sorg, Christian; Drzezga, Alexander

    2014-04-30

    Over the last decade, synchronized resting-state fluctuations of blood oxygenation level-dependent (BOLD) signals between remote brain areas [so-called BOLD resting-state functional connectivity (rs-FC)] have gained enormous relevance in systems and clinical neuroscience. However, the neural underpinnings of rs-FC are still incompletely understood. Using simultaneous positron emission tomography/magnetic resonance imaging we here directly investigated the relationship between rs-FC and local neuronal activity in humans. Computational models suggest a mechanistic link between the dynamics of local neuronal activity and the functional coupling among distributed brain regions. Therefore, we hypothesized that the local activity (LA) of a region at rest determines its rs-FC. To test this hypothesis, we simultaneously measured both LA (glucose metabolism) and rs-FC (via synchronized BOLD fluctuations) during conditions of eyes closed or eyes open. During eyes open, LA increased in the visual system, and the salience network (i.e., cingulate and insular cortices) and the pattern of elevated LA coincided almost exactly with the spatial pattern of increased rs-FC. Specifically, the voxelwise regional profile of LA in these areas strongly correlated with the regional pattern of rs-FC among the same regions (e.g., LA in primary visual cortex accounts for ∼ 50%, and LA in anterior cingulate accounts for ∼ 20% of rs-FC with the visual system). These data provide the first direct evidence in humans that local neuronal activity determines BOLD FC at rest. Beyond its relevance for the neuronal basis of coherent BOLD signal fluctuations, our procedure may translate into clinical research particularly to investigate potentially aberrant links between local dynamics and remote functional coupling in patients with neuropsychiatric disorders. PMID:24790196

  4. Development of [F-18]-Labeled Amyloid Imaging Agents for PET

    SciTech Connect

    Mathis, CA

    2007-05-09

    The applicant proposes to design and synthesize a series of fluorine-18-labeled radiopharmaceuticals to be used as amyloid imaging agents for positron emission tomography (PET). The investigators will conduct comprehensive iterative in vitro and in vivo studies based upon well defined acceptance criteria in order to identify lead agents suitable for human studies. The long term goals are to apply the selected radiotracers as potential diagnostic agents of Alzheimer's disease (AD), as surrogate markers of amyloid in the brain to determine the efficacy of anti-amyloid therapeutic drugs, and as tools to help address basic scientific questions regarding the progression of the neuropathology of AD, such as testing the "amyloid cascade hypothesis" which holds that amyloid accumulation is the primary cause of AD.

  5. Diagnostic utility of FDG-PET in neurolymphomatosis: report of five cases.

    PubMed

    Kinoshita, Hisanori; Yamakado, Hodaka; Kitano, Toshiyuki; Kitamura, Akihiro; Yamashita, Hirofumi; Miyamoto, Masakazu; Hitomi, Takefumi; Okada, Tomohisa; Nakamoto, Yuji; Sawamoto, Nobukatsu; Takaori-Kondo, Akifumi; Takahashi, Ryosuke

    2016-09-01

    Neurolymphomatosis (NL) is a rare condition involving the infiltration of lymphoma cells into the peripheral nervous system. NL can be primary or secondary in the setting of an unknown or known hematologic malignancy, respectively. Here, we report five cases in which F-18 2-fluoro-2-deoxy-glucose positron emission tomography/computed tomography (F-18 FDG-PET/CT) had great value for diagnosing NL. Two cases were rare primary NL, and the other three were secondary NL. Clinical presentations were asymmetric sensorimotor disturbances in the extremities with or without involvement of cranial nerves. Furthermore, all patients experienced spontaneous pain in the face or affected extremities. Cerebrospinal fluid analysis was cytologically negative in two of five cases. Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) detected abnormalities in the cranial nerves, nerve roots, and cauda equina in all cases except case 1 and the recurrent stage of case 2. F-18 FDG-PET/CT showed clear visualization of almost all the lymphomatous involvement of peripheral nerves and other tissues in all patients. Furthermore, F-18 FDG-PET/CT detected abnormalities including asymptomatic lesions that were not detected with MRI, and also identified the appropriate lesion for diagnostic biopsy. However, as in case 3, the lesions in the left oculomotor nerve and the cauda equina were detected only with Gd-enhanced MRI, which has superior spatial resolution. In conclusion, F-18 FDG-PET/CT is a sensitive modality that can suggest the presence of malignancy and identify appropriate places for diagnostic biopsies. It is especially useful when combined with Gd-enhanced MRI, even in patients with primary NL that is usually difficult to diagnose. PMID:27286845

  6. False positivity of FDG-PET/CT in a child with Hodgkin disease.

    PubMed

    Beker, Dildar Bahar; Berrak, Su Gulsun; Canpolat, Cengiz; Tugtepe, Halil; Ones, Tunc; Tecimer, Tulay

    2008-04-01

    Role of Positron Emission Tomography (PET) with F-18-2-fluoro-2-deoxy-D-glucose (FDG) in staging of Hodgkin disease is well established despite several controversies. We report a Stage III Hodgkin lymphoma patient with false positive FDG-PET/CT results. Seven-year-old male with Hodgkin lymphoma was in remission at end of chemotherapy. At third and fourth month of postchemotherapy follow-up, increased Gallium uptake and positive FDG-PET/CT in right lower quadrant of abdomen was observed. Open biopsy revealed lymphoid hyperplasia. He has been followed for 21 months without any evidence of disease. Despite its documented benefit, we believe that results of FDG-PET/CT should be interpreted with great caution in order to avoid unnecessary interventions. PMID:17417791

  7. [HPLC enantioseparation, absolute configuration determination and anti-HIV-1 activity of (±)-F18 enantiomers].

    PubMed

    Zhang, Lei-lei; Xue, Hai; Li, Li; Lu, Xiao-fan; Chen, Zhi-wei; Lu, Gang

    2015-06-01

    Racemic (±)-F18 (10-chloromethyl-11-demethyl-12-oxo-calanolide A), an analog of nature product (+)-calanolide A, is a new anti-HIV-1 nonnucleoside reverse transcript inhibitor (NNRTI). A successful enantioseparation of (±)-F18 offering (R)-F18 and (S)-F18 was achieved by a chiral stationary phase prepared HPLC. Their absolute configurations were determined by measurement of their electronic circular dichroisms combined with modem quantum-chemical calculations. Further investigation revealed that (R)-F18 and (S)-F18 shared a similar anti-HIV activities, however, (R)-F18 was more potent than (S)-F18 against wild-type virus, K101E mutation and P225H mutation pseudoviruses. PMID:26521445

  8. The brain metabolic activity after resuscitation with liposome-encapsulated hemoglobin in a rat model of hypovolemic shock.

    PubMed

    Rao, Geeta; Hedrick, Andria F; Yadav, Vivek R; Xie, Jun; Hussain, Alamdar; Awasthi, Vibhudutta

    2015-09-01

    We examined the effect of resuscitation with liposome-encapsulated hemoglobin (LEH) on cerebral bioenergetics in a rat model of 45% hypovolemia. The rats were resuscitated with isovolemic LEH or saline after 15 minutes of shock and followed up to 6 hours. Untreated hypovolemic rats received no fluid. The cerebral uptake of F-18-fluorodeoxyglucose (FDG) was measured by PET, and at 6 hours, the brain was collected for various assays. Hypovolemia decreased cellular adenosine triphosphate (ATP), phosphocreatine, nicotinamide adenine dinucleotide (NAD)/NADH ratio, citrate synthase activity, glucose-6-phosphate, and nerve growth factor (NGF), even when FDG uptake remained unchanged. The FDG uptake was reduced by saline, but not by LEH infusion. The reduced FDG uptake in saline group was associated with a decrease in hexokinase I expression. The LEH infusion effectively restored ATP content, NAD/NADH ratio, and NGF expression, and reduced the hypovolemia-induced accumulation of pyruvate and ubiquitinated proteins; in comparison, saline was significantly less effective. The LEH infusion was associated with low pH and high anion gap, indicating anionic gap acidosis. The results suggest that hypovolemic shock perturbs glucose metabolism at the level of pyruvate utilization, resulting in deranged cerebral energy stores. The correction of volume and oxygen deficits by LEH recovers the cerebral metabolism and creates a prosurvival phenotype.

  9. The brain metabolic activity after resuscitation with liposome-encapsulated hemoglobin in a rat model of hypovolemic shock.

    PubMed

    Rao, Geeta; Hedrick, Andria F; Yadav, Vivek R; Xie, Jun; Hussain, Alamdar; Awasthi, Vibhudutta

    2015-09-01

    We examined the effect of resuscitation with liposome-encapsulated hemoglobin (LEH) on cerebral bioenergetics in a rat model of 45% hypovolemia. The rats were resuscitated with isovolemic LEH or saline after 15 minutes of shock and followed up to 6 hours. Untreated hypovolemic rats received no fluid. The cerebral uptake of F-18-fluorodeoxyglucose (FDG) was measured by PET, and at 6 hours, the brain was collected for various assays. Hypovolemia decreased cellular adenosine triphosphate (ATP), phosphocreatine, nicotinamide adenine dinucleotide (NAD)/NADH ratio, citrate synthase activity, glucose-6-phosphate, and nerve growth factor (NGF), even when FDG uptake remained unchanged. The FDG uptake was reduced by saline, but not by LEH infusion. The reduced FDG uptake in saline group was associated with a decrease in hexokinase I expression. The LEH infusion effectively restored ATP content, NAD/NADH ratio, and NGF expression, and reduced the hypovolemia-induced accumulation of pyruvate and ubiquitinated proteins; in comparison, saline was significantly less effective. The LEH infusion was associated with low pH and high anion gap, indicating anionic gap acidosis. The results suggest that hypovolemic shock perturbs glucose metabolism at the level of pyruvate utilization, resulting in deranged cerebral energy stores. The correction of volume and oxygen deficits by LEH recovers the cerebral metabolism and creates a prosurvival phenotype. PMID:25944591

  10. Metabolism of human gliomas: Assessment with H-1 MR spectroscopy and F-18 fluorodeoxyglucose PET

    SciTech Connect

    Alger, J.R.; Frank, J.A.; Bizzi, A.; Fulham, M.J.; DeSouza, B.X.; Duhaney, M.O.; Inscoe, S.W.; Black, J.L.; van Zijl, P.C.; Moonen, C.T. , Bethesda, MD )

    1990-12-01

    Localized hydrogen-1 magnetic resonance (MR) spectroscopy and fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) were employed to obtain metabolic information from intracranial gliomas. Advantages and difficulties associated with comparison of results from the two modalities were realized. Forty patients were studied with H-1 MR spectroscopy. MR signal intensities from lactate, N-acetylaspartate (NAA), choline, and creatine from a volume of interest containing the tumor and a contralateral volume were obtained and evaluated. NAA signal intensities were generally decreased in the tumor spectra, and choline signal intensities were elevated. H-1 MR spectroscopy was unsuccessful in eight patients, and FDG PET scans were not obtained in four of the patients with successful MR spectroscopic examinations. Lactate signal intensity was detected in 10 of the 28 patients who had successful H-1 MR spectroscopic and FDG PET studies. Lactate signal intensities were observed in lesions shown at FDG PET to be hypermetabolic, as well as in lesions found to be hypometabolic.

  11. Real-time PCR for differentiation of F18 variants among enterotoxigenic and Shiga toxin-producing Escherichia coli from piglets with diarrhoea and oedema disease.

    PubMed

    Byun, Jae-Won; Jung, Byeong Yeal; Kim, Ha-Young; Fairbrother, John M; Lee, Myoung-Heon; Lee, Wan-Kyu

    2013-11-01

    One-step real-time PCR using one set of primers and four probes was developed for differentiation of F18 variants (F18 common, F18ab, F18ac, F18new variant) of enterotoxigenic (ETEC) and Shiga toxin-producing (STEC) Escherichia coli from piglets with diarrhoea and oedema disease. The limits of detection for F18common, F18ab, F18ac, and F18new variant were 10(7), 10(7), 10(5) and 10(7)colony forming units/g faeces, respectively. Of 94 Korean isolates of E. coli encoding F18, 70 were F18ac (43 STEC/ETEC, 4 STEC and 23 ETEC), 15 were F18ab (all STEC) and nine were F18new variant (1 STEC/ETEC, 7 STEC, 1 ETEC). PMID:23992871

  12. STM study of C60F18 high dipole moment molecules on Au(111)

    NASA Astrophysics Data System (ADS)

    Bairagi, K.; Bellec, A.; Chumakov, R. G.; Menshikov, K. A.; Lagoute, J.; Chacon, C.; Girard, Y.; Rousset, S.; Repain, V.; Lebedev, A. M.; Sukhanov, L. P.; Svechnikov, N. Yu.; Stankevich, V. G.

    2015-11-01

    Scanning tunneling microscopy and spectroscopy studies of C60F18 molecules deposited on Au(111) are reported and compared to C60 molecules both at liquid helium temperature and room temperature (RT). Whereas adsorption and electronic properties of C60F18 single molecules were studied at low temperature (LT), self-assemblies were investigated at RT. In both cases, the fluorine atoms of the C60F18 molecules are pointed towards the surface. Individual C60F18 molecules on Au(111) have a HOMO-LUMO gap of 2.9 eV. The self-assembled islands exhibit a close-packed hexagonal lattice with amorphous borders. The comparison with C60 molecules clearly demonstrates the influence of the C60F18 electric dipole moment (EDM) on the electronic properties of single molecules and on the thermodynamics of self-assembled islands. Besides, the apparent height value of a separate molecule increases in a self-assembly environment as a result of a depolarization phenomenon.

  13. Results From F-18B Stability and Control Parameter Estimation Flight Tests at High Dynamic Pressures

    NASA Technical Reports Server (NTRS)

    Moes, Timothy R.; Noffz, Gregory K.; Iliff, Kenneth W.

    2000-01-01

    A maximum-likelihood output-error parameter estimation technique has been used to obtain stability and control derivatives for the NASA F-18B Systems Research Aircraft. This work has been performed to support flight testing of the active aeroelastic wing (AAW) F-18A project. The goal of this research is to obtain baseline F-18 stability and control derivatives that will form the foundation of the aerodynamic model for the AAW aircraft configuration. Flight data have been obtained at Mach numbers between 0.85 and 1.30 and at dynamic pressures ranging between 600 and 1500 lbf/sq ft. At each test condition, longitudinal and lateral-directional doublets have been performed using an automated onboard excitation system. The doublet maneuver consists of a series of single-surface inputs so that individual control-surface motions cannot be correlated with other control-surface motions. Flight test results have shown that several stability and control derivatives are significantly different than prescribed by the F-18B aerodynamic model. This report defines the parameter estimation technique used, presents stability and control derivative results, compares the results with predictions based on the current F-18B aerodynamic model, and shows improvements to the nonlinear simulation using updated derivatives from this research.

  14. Ground-Recorded Sonic Boom Signatures of F-18 Aircraft in Formation Flight

    NASA Technical Reports Server (NTRS)

    Bahm, Catherine M.; Haering, Edward A., Jr.

    1996-01-01

    Two F-18 aircraft were flown, one above the other, in two formations, in order for the shock systems of the two aircraft to merge and propagate to the ground. The first formation had the canopy of the lower F-18 in the tail shock of the upper F-18 (called tail-canopy). The second formation had the canopy of the lower F- 18 in the inlet shock of the upper F-18 (called inlet-canopy). The flight conditions were Mach 1.22 and an altitude of 23,500 ft . An array of five sonic boom recorders was used on the ground to record the sonic boom signatures. This paper describes the flight test technique and the ground level sonic boom signatures. The tail-canopy formation resulted in two, separated, N-wave signatures. Such signatures probably resulted from aircraft positioning error. The inlet-canopy formation yielded a single modified signature; two recorders measured an approximate flattop signature. Loudness calculations indicated that the single inlet-canopy signatures were quieter than the two, separated tail-canopy signatures. Significant loudness occurs after a sonic boom signature. Such loudness probably comes from the aircraft engines.

  15. Research flight-control system development for the F-18 high alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Pahle, Joseph W.; Powers, Bruce; Regenie, Victoria; Chacon, Vince; Degroote, Steve; Murnyak, Steven

    1991-01-01

    The F-18 high alpha research vehicle was recently modified by adding a thrust vectoring control system. A key element in the modification was the development of a research flight control system integrated with the basic F-18 flight control system. Discussed here are design requirements, system development, and research utility of the resulting configuration as an embedded system for flight research in the high angle of attack regime. Particular emphasis is given to control system modifications and control law features required for high angle of attack flight. Simulation results are used to illustrate some of the thrust vectoring control system capabilities and predicted maneuvering improvements.

  16. F-18 SRA closeup of nose cap showing Advanced L-Probe Air Data Integration experiment

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This L-shaped probe mounted on the forward fuselage of a modified F-18 Systems Research Aircraft was the focus of an air data collection experiment flown at NASA's Dryden Flight Research Center, Edwards, California. The Advanced L-Probe Air Data Integration (ALADIN) experiment focused on providing pilots with angle-of-attack and angle-of-sideslip information as well as traditional airspeed and altitude data from a single system. For the experiment, the probes--one mounted on either side of the F-18's forward fuselage--were hooked to a series of four transducers, which relayed pressure measurements to an on-board research computer.

  17. Nanobody Mediated Inhibition of Attachment of F18 Fimbriae Expressing Escherichia coli

    PubMed Central

    Moonens, Kristof; De Kerpel, Maia; Coddens, Annelies; Cox, Eric; Pardon, Els; Remaut, Han; De Greve, Henri

    2014-01-01

    Post-weaning diarrhea and edema disease caused by F18 fimbriated E. coli are important diseases in newly weaned piglets and lead to severe production losses in farming industry. Protective treatments against these infections have thus far limited efficacy. In this study we generated nanobodies directed against the lectin domain of the F18 fimbrial adhesin FedF and showed in an in vitro adherence assay that four unique nanobodies inhibit the attachment of F18 fimbriated E. coli bacteria to piglet enterocytes. Crystallization of the FedF lectin domain with the most potent inhibitory nanobodies revealed their mechanism of action. These either competed with the binding of the blood group antigen receptor on the FedF surface or induced a conformational change in which the CDR3 region of the nanobody displaces the D″-E loop adjacent to the binding site. This D″-E loop was previously shown to be required for the interaction between F18 fimbriated bacteria and blood group antigen receptors in a membrane context. This work demonstrates the feasibility of inhibiting the attachment of fimbriated pathogens by employing nanobodies directed against the adhesin domain. PMID:25502211

  18. CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a

    PubMed Central

    Vaivoda, Rachel; Vaine, Christine; Boerstler, Cassandra; Galloway, Kristy; Christmas, Peter

    2015-01-01

    CYP4Fs were first identified as enzymes that catalyze hydroxylation of leukotriene B4 (LTB4). CYP4F18 has an unusual expression in neutrophils and was predicted to play a role in regulating LTB4-dependent inflammation. We compared chemotaxis of wild-type and Cyp4f18 knockout neutrophils using an in vitro assay. There was no significant difference in the chemotactic response to LTB4, but the response to complement component C5a increased 1.9–2.25-fold in knockout cells compared to wild-type (P < 0.01). This increase was still observed when neutrophils were treated with inhibitors of eicosanoid synthesis. There were no changes in expression of other CYP4 enzymes in knockout neutrophils that might compensate for loss of CYP4F18 or lead to differences in activity. A mouse model of dextran sodium sulfate colitis was used to investigate the consequences of increased C5a-dependent chemotaxis in vivo, but there was no significant difference in weight loss, disease activity, or colonic tissue myeloperoxidase between wild-type and Cyp4f18 knockout mice. This study demonstrates the limitations of inferring CYP4F function based on an ability to use LTB4 as a substrate, points to expanding roles for CYP4F enzymes in immune regulation, and underscores the in vivo challenges of CYP knockout studies. PMID:26613087

  19. CYP4F18-Deficient Neutrophils Exhibit Increased Chemotaxis to Complement Component C5a.

    PubMed

    Vaivoda, Rachel; Vaine, Christine; Boerstler, Cassandra; Galloway, Kristy; Christmas, Peter

    2015-01-01

    CYP4Fs were first identified as enzymes that catalyze hydroxylation of leukotriene B4 (LTB4). CYP4F18 has an unusual expression in neutrophils and was predicted to play a role in regulating LTB4-dependent inflammation. We compared chemotaxis of wild-type and Cyp4f18 knockout neutrophils using an in vitro assay. There was no significant difference in the chemotactic response to LTB4, but the response to complement component C5a increased 1.9-2.25-fold in knockout cells compared to wild-type (P < 0.01). This increase was still observed when neutrophils were treated with inhibitors of eicosanoid synthesis. There were no changes in expression of other CYP4 enzymes in knockout neutrophils that might compensate for loss of CYP4F18 or lead to differences in activity. A mouse model of dextran sodium sulfate colitis was used to investigate the consequences of increased C5a-dependent chemotaxis in vivo, but there was no significant difference in weight loss, disease activity, or colonic tissue myeloperoxidase between wild-type and Cyp4f18 knockout mice. This study demonstrates the limitations of inferring CYP4F function based on an ability to use LTB4 as a substrate, points to expanding roles for CYP4F enzymes in immune regulation, and underscores the in vivo challenges of CYP knockout studies.

  20. Synthesis of Fluorine-Containing Phosphodiesterase 10A (PDE10A) Inhibitors and the In Vivo Evaluation of F-18 Labeled PDE10A PET Tracers in Rodent and Nonhuman Primate

    PubMed Central

    Li, Junfeng; Zhang, Xiang; Jin, Hongjun; Fan, Jinda; Flores, Hubert; Perlmutter, Joel S.; Tu, Zhude

    2015-01-01

    A series of fluorine-containing PDE10A inhibitors were designed and synthesized to improve the metabolic stability of [11C]MP-10. Twenty of the 22 new analogues had high potency and selectivity for PDE10A: 18a–j, 19d–j, 20a–b, and 21b had IC50 values <5 nM for PDE10A. Seven F-18 labeled compounds [18F]18a–e, [18F]18g, and [18F]20a were radiosynthesized by 18F-introduction onto the quinoline rather than the pyrazole moiety of the MP-10 pharmacophore and performed in vivo evaluation. Biodistribution studies in rats showed ~2-fold higher activity in the PDE10A-enriched striatum than nontarget brain regions; this ratio increased from 5 to 30 min postinjection, particularly for [18F]18a–d and [18F]20a. Micro-PET studies of [18F]18d and [18F]20a in nonhuman primates provided clear visualization of striatum with suitable equilibrium kinetics and favorable metabolic stability. These results suggest this strategy may identify a 18F-labeled PET tracer for quantifying the levels of PDE10A in patients with CNS disorders including Huntington’s disease and schizophrenia. PMID:26430878

  1. F-18 SRA closeup of nose cap showing new flush air data system sensor holes

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The small numbers on the nose of this F-18 aircraft at NASA's Dryden Flight Research Center, Edwards, California, show the locations of 11 tiny holes which are an integral part of a new air data system installed on the aircraft. The Real-Time Flush Air Data Sensing system measures the speed and direction of the airflow past the aircraft and its altitude, similar to standard air data systems. It incorporates flush-mounted pressure taps, miniature transducers and an advanced research computer to give pilots more accurate information than standard systems employing external probes can provide. Developed by Dryden researchers in cooperation with Honeywell's Research and Technology Center, Minneapolis, Minnesota, the system was flight tested on Dryden's Systems Research Aircraft (SRA) last year, and is now being used as a precise reference for other air data systems currently being evaluated on the modified F-18.

  2. Data Impact of the DMSP F18 SSULI UV Data on the Operational GAIM Model

    NASA Astrophysics Data System (ADS)

    Dandenault, P. B.; Metzler, C. A.; Nicholas, A. C.; Coker, C.; Budzien, S. A.; Chua, D. H.; Finne, T. T.; Dymond, K.; Walker, P. W.; Schunk, R. W.; Scherliess, L.; Gardner, L. C.

    2011-12-01

    The Naval Research Laboratory (NRL) has developed five ultraviolet remote sensing instruments for the United States Air Force (USAF) Defense Meteorological Satellite Program (DMSP). The DMSP satellites are launched in a near-polar, sun-synchronous orbit at an altitude of approximately 830 km. Each Special Sensor Ultraviolet Limb Imager (SSULI) instrument measures vertical profiles of the natural airglow radiation from atoms, molecules and ions in the upper atmosphere and ionosphere by viewing the earth's limb within a tangent altitude range of approximately 50 km to 750 km. Limb observations are made from the extreme ultraviolet (EUV) to the far ultraviolet (FUV) over the wavelength range of 80 nm to 170 nm, with 1.8 nm resolution. Data products from SSULI observations include nightglow and dayglow Sensor Data Records (SDRs), as well as Environmental Data Records (EDRs) which contain vertical profiles of electron (Ne) densities, N2, O2, O, O+, and Temperature, hmF2, NmF2 and vertical Total Electron Content (TEC). On October 18, 2009, the third SSULI sensor launched from Vandenberg Air Force Base aboard the DMSP F18 spacecraft. The Calibration and Validation of the F18 instrument has completed and the SSULI program is scheduled to go operational at the Air Force Weather Agency (AFWA) in Fall 2011. The SSULI F18 data are ingested by the Global Assimilation of Ionospheric Measurements (GAIM) space weather model, which was developed by Utah State University and has been used operationally at AFWA since February 2006. A brief overview of the SSULI F18 SDR data assimilation process with GAIM is provided and the impact of the SSULI 1356 Å emission on the GAIM model is examined for spring and summer 2011 nightside data in the low-latitude region.

  3. Ground-recorded sonic boom signatures of F-18 aircraft formation flight

    NASA Technical Reports Server (NTRS)

    Bahm, Catherine M.; Haering, Edward A., Jr.

    1995-01-01

    Two F-18 aircraft were flown, one above the other, in two formations, in order for the shock systems of the two aircraft to merge and propagate to the ground. The first formation had the canopy of the lower F-18 in the inlet shock of the upper F-18 (called inlet-canopy). The flight conditions were Mach 1.22 and an altitude of 23,500 ft. An array of five sonic boom recorders was used on the ground to record the sonic boom signatures. This paper describes the flight test technique and the ground level sonic boom signatures. The tail-canopy formation resulted in two, separated, N-wave signatures. Such signatures probably resulted from aircraft positioning error. The inlet-canopy formation yielded a single modified signature; two recorders measured an approximate flattop signature. Loudness calculations indicated that the single inlet-canopy signatures were quieter than the two, separated tail-canopy signatures. Significant loudness occurs after a sonic boom signature. Such loudness probably comes from the aircraft engines.

  4. Microarray analysis of differential gene expression in sensitive and resistant pig to Escherichia coli F18.

    PubMed

    Bao, W B; Ye, L; Pan, Z Y; Zhu, J; Du, Z D; Zhu, G Q; Huang, X G; Wu, S L

    2012-10-01

    In this study, Agilent two-colour microarray-based gene expression profiling was used to detect differential gene expression in duodenal tissues collected from eight full-sib pairs of Sutai pigs differing in adhesion phenotype (sensitivity and resistance to Escherichia coli F18). Using a two-fold change minimum threshold, we found 18 genes that were differentially expressed (10 up-regulated and eight down-regulated) between the sensitive and resistant animal groups. Our gene ontology analysis revealed that these differentially expressed genes are involved in a variety of biological processes, including immune responses, extracellular modification (e.g. glycosylation), cell adhesion and signal transduction, all of which are related to the anabolic metabolism of glycolipids, as well as to inflammation- and immune-related pathways. Based on the genes identified in the screen and the pathway analysis results, real-time PCR was used to test the involvement of ST3GAL1 and A genes (of glycolipid-related pathways), SLA-1 and SLA-3 genes (of inflammation- and immune-related pathways), as well as the differential genes FUT1, TAP1 and SLA-DQA. Subsequently, real-time PCR was performed to validate seven differentially expressed genes screened out by the microarray approach, and sufficient consistency was observed between the two methods. The results support the conclusion that these genes are related to the E. coli F18 receptor and susceptibility to E. coli F18. PMID:22497274

  5. FDG PET/CT imaging in canine cancer patients.

    PubMed

    Hansen, Anders E; McEvoy, Fintan; Engelholm, Svend A; Law, Ian; Kristensen, Annemarie T

    2011-01-01

    2-Deoxy-2-[¹⁸F]fluoro-D-glucose positron emission tomography/computed tomography (FDG PET/CT) is becoming increasingly available as an imaging modality in veterinary medicine. The purpose of this study was to report semiquantitative standard uptake values (SUV) of malignant and nonmalignant tissues and organs in canine cancer patients. FDG PET/CT was performed in 14 dogs including, nine mesenchymal tumors, four carcinomas, and one incompletely excised mast cell tumor. A generally higher FDG uptake was observed in carcinomas relative to sarcomas. Maximum SUV of carcinomas ranged from 7.6 to 27.0, and for sarcomas from 2.0 to 10.6. The FDG SUV of several organs and tissues, including regional brain uptake is reported, to serve as a reference for future FDG PET studies in canine cancer patients. Several potential pitfalls have been recognized in interpretation of FDG PET images of human patients, a number of these were also observed in this study.

  6. F-18 chase craft with NASA test pilots Schneider and Fulton

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Ed Schneider, (left), is the project pilot for the F-18 High Angle of Attack program at NASA's Dryden Flight Research Center, Edwards, California. He has been a NASA research pilot at Dryden since 1983. In addition to his assignment with the F-18 High Angle of Attack program, Schneider is a project pilot for the F-15B aeronautical research aircraft, the NASA NB-52B launch aircraft, and the SR-71 'Blackbird' aircraft. He is a Fellow and was the 1994 President of the Society of Experimental Test Pilots. In 1996 he was awarded the NASA Exceptional Service Medal. Schneider is seen here with Fitzhugh L. Fulton Jr., (right), who was a civilian research pilot at Dryden. from August 1, 1966, until July 3, 1986, following 23 years of service as a pilot in the U.S. Air Force. Fulton was the project pilot on all early tests of the 747 Shuttle Carrier Aircraft (SCA) used to air launch the Space Shuttle prototype Enterprise in the Approach and Landing Tests (ALT) at Dryden in l977. For his work in the ALT program, Fulton received NASA's Exceptional Service Medal. He also received the Exceptional Service Medal again in 1983 for flying the 747 SCA during the European tour of the Space Shuttle Enterprise. During his career at Dryden, Fulton was project pilot on NASA's NB-52B launch aircraft used to air launch a variety of piloted and unpiloted research aircraft, including the X-15s and lifting bodies. He flew the XB-70 prototype supersonic bomber on both NASA-USAF tests and NASA research flights during the late 1960s, attaining speeds exceeding Mach 3. He was also a project pilot on the YF-12A and YF-12C research program from April 14, 1969, until September 25, 1978. The F/A-18 Hornet seen behind them is used primarily as a safety chase and support aircraft at NASA's Dryden Flight Research Center, Edwards, Calif. As support aircraft, the F-18's are used for safety chase, pilot proficiency and aerial photography. As a safety chase aircraft, F-18's, flown by research pilots

  7. Analysis of the Metabolic and Structural Brain Changes in Patients With Torture-Related Post-Traumatic Stress Disorder (TR-PTSD) Using ¹⁸F-FDG PET and MRI.

    PubMed

    Zandieh, Shahin; Bernt, Reinhard; Knoll, Peter; Wenzel, Thomas; Hittmair, Karl; Haller, Joerg; Hergan, Klaus; Mirzaei, Siroos

    2016-04-01

    Many people exposed to torture later suffer from torture-related post-traumatic stress disorder (TR-PTSD). The aim of this study was to analyze the morphologic and functional brain changes in patients with TR-PTSD using magnetic resonance imaging (MRI) and positron emission tomography (PET). This study evaluated 19 subjects. Thirteen subcortical brain structures were evaluated using FSL software. On the T1-weighted images, normalized brain volumes were measured using SIENAX software. The study compared the volume of the brain and 13 subcortical structures in 9 patients suffering from TR-PTSD after torture and 10 healthy volunteers (HV). Diffusion-weighted imaging (DWI) was performed in the transverse plane. In addition, the 18F-FDG PET data were evaluated to identify the activity of the elected regions. The mean left hippocampal volume for the TR-PTSD group was significantly lower than in the HV group (post hoc test (Bonferroni) P < 0.001). There was a significant difference between the gray matter volume of the patients with TR-PTSD and the HV group (post hoc test (Bonferroni) P < 0.001). The TR-PTSD group showed low significant expansion of the ventricles in contrast to the HV group (post hoc test (Bonferroni) P < 0.001). Diffusion-weighted imaging revealed significant differences in the right frontal lobe and the left occipital lobe between the TR-PTSD and HV group (post hoc test (Bonferroni) P < 0.001). Moderate hypometabolism was noted in the occipital lobe in 6 of the 9 patients with TR-PTSD, in the temporal lobe in 1 of the 9 patients, and in the caudate nucleus in 5 of the 9 patients. In 2 cases, additional hypometabolism was observed in the posterior cingulate cortex and in the parietal and frontal lobes. The findings from this study show that TR-PTSD might have a deleterious influence on a set of specific brain structures. This study also demonstrated that PET combined with MRI is sensitive in detecting possible metabolic and structural

  8. Analysis of the Metabolic and Structural Brain Changes in Patients With Torture-Related Post-Traumatic Stress Disorder (TR-PTSD) Using 18F-FDG PET and MRI

    PubMed Central

    Zandieh, Shahin; Bernt, Reinhard; Knoll, Peter; Wenzel, Thomas; Hittmair, Karl; Haller, Joerg; Hergan, Klaus; Mirzaei, Siroos

    2016-01-01

    Abstract Many people exposed to torture later suffer from torture-related post-traumatic stress disorder (TR-PTSD). The aim of this study was to analyze the morphologic and functional brain changes in patients with TR-PTSD using magnetic resonance imaging (MRI) and positron emission tomography (PET). This study evaluated 19 subjects. Thirteen subcortical brain structures were evaluated using FSL software. On the T1-weighted images, normalized brain volumes were measured using SIENAX software. The study compared the volume of the brain and 13 subcortical structures in 9 patients suffering from TR-PTSD after torture and 10 healthy volunteers (HV). Diffusion-weighted imaging (DWI) was performed in the transverse plane. In addition, the 18F-FDG PET data were evaluated to identify the activity of the elected regions. The mean left hippocampal volume for the TR-PTSD group was significantly lower than in the HV group (post hoc test (Bonferroni) P < 0.001). There was a significant difference between the gray matter volume of the patients with TR-PTSD and the HV group (post hoc test (Bonferroni) P < 0.001). The TR-PTSD group showed low significant expansion of the ventricles in contrast to the HV group (post hoc test (Bonferroni) P < 0.001). Diffusion-weighted imaging revealed significant differences in the right frontal lobe and the left occipital lobe between the TR-PTSD and HV group (post hoc test (Bonferroni) P < 0.001). Moderate hypometabolism was noted in the occipital lobe in 6 of the 9 patients with TR-PTSD, in the temporal lobe in 1 of the 9 patients, and in the caudate nucleus in 5 of the 9 patients. In 2 cases, additional hypometabolism was observed in the posterior cingulate cortex and in the parietal and frontal lobes. The findings from this study show that TR-PTSD might have a deleterious influence on a set of specific brain structures. This study also demonstrated that PET combined with MRI is sensitive in detecting possible metabolic and

  9. Analysis of the Metabolic and Structural Brain Changes in Patients With Torture-Related Post-Traumatic Stress Disorder (TR-PTSD) Using ¹⁸F-FDG PET and MRI.

    PubMed

    Zandieh, Shahin; Bernt, Reinhard; Knoll, Peter; Wenzel, Thomas; Hittmair, Karl; Haller, Joerg; Hergan, Klaus; Mirzaei, Siroos

    2016-04-01

    Many people exposed to torture later suffer from torture-related post-traumatic stress disorder (TR-PTSD). The aim of this study was to analyze the morphologic and functional brain changes in patients with TR-PTSD using magnetic resonance imaging (MRI) and positron emission tomography (PET). This study evaluated 19 subjects. Thirteen subcortical brain structures were evaluated using FSL software. On the T1-weighted images, normalized brain volumes were measured using SIENAX software. The study compared the volume of the brain and 13 subcortical structures in 9 patients suffering from TR-PTSD after torture and 10 healthy volunteers (HV). Diffusion-weighted imaging (DWI) was performed in the transverse plane. In addition, the 18F-FDG PET data were evaluated to identify the activity of the elected regions. The mean left hippocampal volume for the TR-PTSD group was significantly lower than in the HV group (post hoc test (Bonferroni) P < 0.001). There was a significant difference between the gray matter volume of the patients with TR-PTSD and the HV group (post hoc test (Bonferroni) P < 0.001). The TR-PTSD group showed low significant expansion of the ventricles in contrast to the HV group (post hoc test (Bonferroni) P < 0.001). Diffusion-weighted imaging revealed significant differences in the right frontal lobe and the left occipital lobe between the TR-PTSD and HV group (post hoc test (Bonferroni) P < 0.001). Moderate hypometabolism was noted in the occipital lobe in 6 of the 9 patients with TR-PTSD, in the temporal lobe in 1 of the 9 patients, and in the caudate nucleus in 5 of the 9 patients. In 2 cases, additional hypometabolism was observed in the posterior cingulate cortex and in the parietal and frontal lobes. The findings from this study show that TR-PTSD might have a deleterious influence on a set of specific brain structures. This study also demonstrated that PET combined with MRI is sensitive in detecting possible metabolic and structural

  10. Attenuation-Corrected vs. Nonattenuation-Corrected 2-Deoxy-2-[F-18]fluoro-d-glucose-Positron Emission Tomography in Oncology, A Systematic Review

    PubMed Central

    Joshi, Urvi; Riphagen, Ingrid I.; Teule, Gerrit J. J.; van Lingen, Arthur; Hoekstra, Otto S.

    2007-01-01

    Purpose To perform a systematic review and meta-analysis to determine the diagnostic accuracy of attenuation-corrected (AC) vs. nonattenuation-corrected (NAC) 2-deoxy-2-[F-18]fluoro-d-glucose-positron emission tomography (FDG-PET) in oncological patients. Procedures Following a comprehensive search of the literature, two reviewers independently assessed the methodological quality of eligible studies. The diagnostic value of AC was studied through its sensitivity/specificity compared to histology, and by comparing the relative lesion detection rate reported with NAC-PET vs. AC, for full-ring and dual-head coincidence PET (FR- and DH-PET, respectively). Results Twelve studies were included. For FR-PET, the pooled sensitivity/specificity on a patient basis was 64/97% for AC and 62/99% for NAC, respectively. Pooled lesion detection with NAC vs. AC was 98% [95% confidence interval (95% CI): 96–99%, n = 1,012 lesions] for FR-PET, and 88% (95% CI:81–94%, n = 288 lesions) for DH-PET. Conclusions Findings suggest similar sensitivity/specificity and lesion detection for NAC vs. AC FR-PET and significantly higher lesion detection for NAC vs. AC DH-PET. PMID:17318671

  11. Changes in Cervical Cancer FDG Uptake During Chemoradiation and Association With Response

    SciTech Connect

    Kidd, Elizabeth A.; Thomas, Maria; Siegel, Barry A.; Dehdashti, Farrokh; Grigsby, Perry W.

    2013-01-01

    Purpose: Previous research showed that pretreatment uptake of F-18 fluorodeoxyglucose (FDG), as assessed by the maximal standardized uptake value (SUV{sub max}) and the variability of uptake (FDG{sub hetero}), predicted for posttreatment response in cervical cancer. In this pilot study, we evaluated the changes in SUV{sub max} and FDG{sub hetero} during concurrent chemoradiation for cervical cancer and their association with post-treatment response. Methods and Materials: Twenty-five patients with stage Ib1-IVa cervical cancer were enrolled. SUV{sub max}, FDG{sub hetero}, and metabolic tumor volume (MTV) were recorded from FDG-positron emission tomography (PET)/computed tomography (CT) scans performed pretreatment and during weeks 2 and 4 of treatment and were evaluated for changes and association with response assessed on 3-month post-treatment FDG-PET/CT. Results: For all patients, the average pretreatment SUV{sub max} was 17.8, MTV was 55.4 cm{sup 3}, and FDG{sub hetero} was -1.33. A similar decline in SUV{sub max} was seen at week 2 compared with baseline and week 4 compared with week 2 (34%). The areas of highest FDG uptake in the tumor remained relatively consistent on serial scans. Mean FDG{sub hetero} decreased during treatment. For all patients, MTV decreased more from week 2 to week 4 than from pretreatment to week 2. By week 4, the average SUV{sub max} had decreased by 57% and the MTV had decreased by 30%. Five patients showed persistent or new disease on 3-month post-treatment PET. These poor responders showed a higher average SUV{sub max}, larger MTV, and greater heterogeneity at all 3 times. Week 4 SUV{sub max} (P=.037), week 4 FDG{sub hetero} (P=.005), pretreatment MTV (P=.008), and pretreatment FDG{sub hetero} (P=.008) were all significantly associated with post-treatment PET response. Conclusions: SUV{sub max} shows a consistent rate of decline during treatment and declines at a faster rate than MTV regresses. Based on this pilot study

  12. New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography

    SciTech Connect

    J. Michael Doster

    2008-12-19

    This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.

  13. 4-[F-18]fluoroproline: A potential tracer for collagen synthesis. Radiosynthesis and biological evaluation

    SciTech Connect

    Hamacher, K.; Herz, M.; Truckenbrodt, R.

    1996-05-01

    Proline is an important constituent of the structural protein collagen. It has been shown that its fluorinated analogs (2S,4S)- and particularly (2S,4R)-4-fluoroproline are also incorporated into collagen (Gottlieb et al., Biochemistry (1965), 4: 2507). 4-[F-18]fluoroproline is therefore a potential probe for studying abnormal collagen synthesis e. g. in tumors, lung fibrosis and liver cirrhosis. We have evaluated the two diastereomeric forms using a transplantable osteosarcoma in mice as an in vivo model for elevated collagen synthesis, and a MCF 7 mamma carcinoma cell line for monolayer incubation studies.

  14. FDG PET imaging in sarcoidosis.

    PubMed

    Sobic-Saranovic, Dragana; Artiko, Vera; Obradovic, Vladimir

    2013-11-01

    The objective of this review is to highlight the clinical utility of FDG-PET/CT for evaluation of patients with chronic sarcoidosis. The emphasis was on the potential advantages and disadvantages of this technique in these patients based on which recommendations were made. The advantage of FDG-PET/CT technique is that it can visualize FDG accumulation in activated inflammatory cells and simultaneously provide PET and CT images. Of particular interest is the use of FDG-PET/CT for the staging and identification of occult sites and sites suitable for biopsy and for the assessment of inflammatory active sarcoidosis in patients with prolonged symptoms, especially when other markers of the disease are within normal values. FDG-PET/CT also provides a better visualization of extrathoracic sites of active sarcoidosis, such as in the bones, liver, spleen, and retroperitoneal lymph nodes. The use of FDG-PET/CT is of special interest in cardiac sarcoidosis because this potentially life-threatening disease is sometimes present in asymptomatic patients. FDG-PET/CT also has a role in the clinical management of patients with chronic persistent sarcoidosis, such as for planning treatment, monitoring response, and long-term follow-up. The limitations of FDG-PET/CT in patients with sarcoidosis are discussed in the context of a "sarcoidosis-lymphoma syndrome" and potentially excessive radiation exposure. Further prospective multicentre studies are needed to refine the clinical applications of FDG-PET/CT in patients with sarcoidosis and drive the field forward.

  15. An Overview of the NASA F-18 High Alpha Research Vehicle

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.; Pahle, Joseph W.; Wilson, R. Joseph; Flick, Bradley C.; Rood, Richard L.

    1996-01-01

    This paper gives an overview of the NASA F-18 High Alpha Research Vehicle. The three flight phases of the program are introduced, along with the specific goals and data examples taken during each phase. The aircraft configuration and systems needed to perform the disciplinary and inter-disciplinary research are discussed. The specific disciplines involved with the flight research are introduced, including aerodynamics, controls, propulsion, systems, and structures. Decisions that were made early in the planning of the aircraft project and the results of those decisions are briefly discussed. Each of the three flight phases corresponds to a particular aircraft configuration, and the research dictated the configuration to be flown. The first phase gathered data with the baseline F-18 configuration. The second phase was the thrust-vectoring phase. The third phase used a modified forebody with deployable nose strakes. Aircraft systems supporting these flights included extensive instrumentation systems, integrated research flight controls using flight control hardware and corresponding software, analog interface boxes to control forebody strakes, a thrust-vectoring system using external post-exit vanes around axisymmetric nozzles, a forebody vortex control system with strakes, and backup systems using battery-powered emergency systems and a spin recovery parachute.

  16. Thrust Vectoring on the NASA F-18 High Alpha Research Vehicle

    NASA Technical Reports Server (NTRS)

    Bowers, Albion H.; Pahle, Joseph W.

    1996-01-01

    Investigations into a multiaxis thrust-vectoring system have been conducted on an F-18 configuration. These investigations include ground-based scale-model tests, ground-based full-scale testing, and flight testing. This thrust-vectoring system has been tested on the NASA F-18 High Alpha Research Vehicle (HARV). The system provides thrust vectoring in pitch and yaw axes. Ground-based subscale test data have been gathered as background to the flight phase of the program. Tests investigated aerodynamic interaction and vane control effectiveness. The ground-based full-scale data were gathered from static engine runs with image analysis to determine relative thrust-vectoring effectiveness. Flight tests have been conducted at the NASA Dryden Flight Research Center. Parameter identification input techniques have been developed. Individual vanes were not directly controlled because of a mixer-predictor function built into the flight control laws. Combined effects of the vanes have been measured in flight and compared to combined effects of the vanes as predicted by the cold-jet test data. Very good agreement has been found in the linearized effectiveness derivatives.

  17. F-18 SRA closeup of nose cap showing new flush air data system sensor holes

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Small numbers on the nose cap of this F-18 Systems Research Aircraft at NASA's Dryden Flight Research Center, Edwards, California, show the locations of 11 tiny holes, which are an integral part of a new air data system installed on the aircraft. The Real-Time Flush Air Data Sensing system measures the speed and direction of the airflow past the aircraft and its altitude, similar to standard air data systems. It differs from those systems by incorporating flush-mounted pressure taps, miniature transducers and an advanced research computer to give the pilot more accurate information than systems employing external probes provide. Stephen A. Whitmore of Dryden's Aerodynamics Branch won NASA's Space Act Award for his development of the Real-Time Flush Air Data Sensing system. The award honors projects which are scientifically or technologically significant to the aeronautics and space community. The system was flight tested on the modified F-18 last year, and is now being used as a precise reference system for other air data systems currently being evaluated on the aircraft.

  18. Performance of an Electro-Hydrostatic Actuator on the F-18 Systems Research Aircraft

    NASA Technical Reports Server (NTRS)

    Navarro, Robert

    1997-01-01

    An electro-hydrostatic actuator was evaluated at NASA Dryden Flight Research Center, Edwards, California. The primary goal of testing this actuator system was the flight demonstration of power-by-wire technology on a primary flight control surface. The electro-hydrostatic actuator uses an electric motor to drive a hydraulic pump and relies on local hydraulics for force transmission. This actuator replaced the F-18 standard left aileron actuator on the F-18 Systems Research Aircraft and was evaluated throughout the Systems Research Aircraft flight envelope. As of July 24, 1997 the electro-hydrostatic actuator had accumulated 23.5 hours of flight time. This paper presents the electro-hydrostatic actuator system configuration and component description, ground and flight test plans, ground and flight test results, and lessons learned. This actuator performs as well as the standard actuator and has more load capability than required by aileron actuator specifications of McDonnell- Douglas Aircraft, St. Louis, Missouri. The electro-hydrostatic actuator system passed all of its ground tests with the exception of one power-off test during unloaded dynamic cycling.

  19. The enthalpy of formation of fullerene fluoride C60F18 and the C-F bond energy

    NASA Astrophysics Data System (ADS)

    Papina, T. S.; Luk'yanova, V. A.; Goryunkov, A. A.; Ioffe, I. N.; Gol'Dt, I. V.; Buyanovskaya, A. G.; Kabaeva, N. M.; Sidorov, L. N.

    2007-10-01

    The enthalpy of combustion of crystalline fullerene fluoride C60F18 was determined in an isoperibolic calorimeter with a rotating platinized bomb, and the enthalpy of formation of the compound was calculated. The enthalpy of sublimation of C60F18 measured earlier was used to calculate the enthalpy of formation of fullerene fluoride in the gas phase and the mean enthalpy of dissociation of C-F bonds in this compound.

  20. A comparison study of 11C-methionine and 18F-fluorodeoxyglucose positron emission tomography-computed tomography scans in evaluation of patients with recurrent brain tumors

    PubMed Central

    Sharma, Rajnish; D’Souza, Maria; Jaimini, Abhinav; Hazari, Puja Panwar; Saw, Sanjeev; Pandey, Santosh; Singh, Dinesh; Solanki, Yachna; Kumar, Nitin; Mishra, Anil K.; Mondal, Anupam

    2016-01-01

    Introduction: 11C-methonine ([11C]-MET) positron emission tomography-computed tomography (PET-CT) is a well-established technique for evaluation of tumor for diagnosis and treatment planning in neurooncology. [11C]-MET reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging (MRI) in stereotactic biopsy planning. This study compared fluorodeoxyglucose (FDG) PET-CT and MET PET-CT in the detection of various brain tumors. Materials and Methods: Sixty-four subjects of brain tumor treated by surgery, chemotherapy, and/or radiotherapy were subjected to [18F]-FDG, [11C]-MET, and MRI scan. The lesion was analyzed semiquantitatively using tumor to normal contralateral ratio. The diagnosis was confirmed by surgery, stereotactic biopsy, clinical follow-up, MRI, or CT scans. Results: Tumor recurrence was found in 5 out of 22 patients on [F-18] FDG scan while [11C]-MET was able to detect recurrence in 18 out of 22 patients in low-grade gliomas. Two of these patients were false positive for the presence of recurrence of tumor and later found to be harboring necrosis. Among oligodendroglioma, medulloblastoma and high-grade glioma out of 42 patients 39 were found to be concordant MET and FDG scans. On semiquantitative analysis, mean T/NT ratio was found to be 2.96 ± 0.94 for lesions positive for recurrence of tumors and 1.18 ± 0.74 for lesions negative for recurrence of tumor on [11C]-MET scan. While the ratio for FDG scan on semiquantitative analysis was found to be 2.05 ± 1.04 for lesions positive for recurrence of tumors and 0.52 ± 0.15 for lesions negative for recurrence of tumors. Conclusion: The study highlight that [11C]-MET is superior to [18F]-FDG PET scans to detect recurrence in low-grade glioma. A cut-off value of target to nontarget value of 1.47 is a useful parameter to distinguish benign from malignant lesion on an [11C]-MET Scan. Both [18F]-FDG and [11C]-MET scans were found to be useful in high-grade astrocytoma

  1. Effects of nonlinear unsteady aerodynamics on performance, stability and control of an F-18 configuration

    NASA Astrophysics Data System (ADS)

    Lin, Guofeng

    Large-amplitude forced oscillation data for an F-18 configuration are analyzed with two modeling methods: Fourier functional analysis to form the indicial integrals, and a generalized dynamic aerodynamic model for stability and control analysis. The indicial integral is first applied to calculate the pitch damping parameter for comparison with the conventional forced oscillation test. It is shown that the reduced frequency affects the damping much more strongly than the test amplitude. Using the indicial integral models in a flight simulation code for an F-18 configuration, it is found that the configuration with unsteady aerodynamics becomes unstable in pitch if the pitch rate is high, in contrast to the quasi-steady configuration which depends mainly on the instantaneous angle of attack. In a pitch-up maneuver in the post-stall regime the configuration with unsteady aerodynamics can stay at a high pitch attitude and angle of attack without losing altitude for a much longer duration than the quasi-steady model. However, the speed will decrease faster because of higher drag. The newly developed generalized dynamic aerodynamic model is of the nonlinear algebraic form with the coefficients being determined from a set of large amplitude oscillatory experimental data by using least-square fitting. The resulting model coefficients are functions of the reduced frequency and amplitude. The new aerodynamic models have been verified with data in harmonic oscillation with a smaller amplitude and in constant pitch-rate motions. The new algebraic models are especially useful in stability and control analysis, and are used in bifurcation analysis and control studies for the same F-18 HARV configuration. The results show significant differences in the equilibrium surfaces and dynamic stability. It is also shown that control gains developed with the conventional quasi-steady aerodynamic data may not be adequate when the effect of unsteady aerodynamics is significant. A numerical

  2. Measurements of glucose phosphorylation with FDG and PET are not reduced by dephosphorylation of FDG-6-phosphate

    SciTech Connect

    Kuwabara, H.; Gjedde, A. )

    1991-04-01

    To improve the measurements of glucose metabolism in the human brain, we imposed biologic constraints on the deoxyglucose model with and without dephosphorylation of FDG-6-phosphate (the k4*- and k3*-models). The constraints included constant transport and phosphorylation ratios (tau and phi) and a common partition volume (K1/k2) for tracer ({sup 18}F)FDG and glucose. In the presence of significant dephosphorylation, the k3*-model yielded time-dependent estimates of the phosphorylation coefficient (k3*), while the K4*-model yielded time-independent estimates. However, the two models yielded practically identical measurements of regional cerebral glucose metabolism in PET studies of six normal volunteers when the phosphorylation affinity ratio (the k3*/k3 ratio of FDG and glucose) and tracer circulation time were 0.30 and 20 min for the k3*-model and 0.33 and 45 min for the k4*-model.

  3. F-18 HARV in flight close-up of actuated nose strakes

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA's F-18 from the Dryden Flight Research Center, Edwards, California, soars over the Mojave Desert while flying the third phase of the HARV (High Alpha Research Vehicle) program. This is a closer look at the set of control surfaces called strakes that were installed in the nose of the aircraft. The strakes, outlined in gold and white, are expected to provide improved yaw control at steep angles of attack. Normally folded flush, the units -- four feet long and six inches wide -- can be opened independently to interact with the nose vortices to produce large side forces for control. Testing involved evaluation of the strakes by themselves as well as combined with the aircraft's Thrust Vectoring System. The strakes were designed by NASA's Langley Research Center, then installed and flight tested at Dryden.

  4. Acute brain metabolic effects of cocaine in rhesus monkeys with a history of cocaine use.

    PubMed

    Henry, Porche' Kirkland; Murnane, Kevin S; Votaw, John R; Howell, Leonard L

    2010-12-01

    Cocaine addiction involves an escalation in drug intake which alters many brain functions. The present study documented cocaine-induced changes in brain metabolic activity as a function of cocaine self-administration history. Experimentally naive rhesus monkeys (N = 6) were given increasing access to cocaine under a fixed-ratio schedule of intravenous (i.v.) drug self-administration. PET imaging with F-18 labeled fluorodeoxyglucose (FDG) was used to measure acute intramuscular (i.m.) cocaine-induced changes in brain metabolism in the cocaine-naïve state, following 60 sessions under limited-access conditions (1 h/day), following 60 sessions under extended-access conditions (4 h/day), and following 4 weeks of drug withdrawal. In the cocaine-naïve state, cocaine-induced increases in brain metabolism were restricted to the prefrontal cortex. As cocaine exposure increased from limited to extended access, metabolic effects expanded throughout the frontal cortex and were induced within the striatum. Conversely, cocaine-induced activation was far less robust following withdrawal. The results highlight a progressive expansion of the metabolic effects of cocaine to include previously unaffected dopamine innervated brain regions as a consequence of cocaine self-administration history. The identification of brain regions progressively influenced by drug exposure may be highly relevant toward efforts to develop treatments for cocaine addiction.

  5. Acute brain metabolic effects of cocaine in rhesus monkeys with a history of cocaine use.

    PubMed

    Henry, Porche' Kirkland; Murnane, Kevin S; Votaw, John R; Howell, Leonard L

    2010-12-01

    Cocaine addiction involves an escalation in drug intake which alters many brain functions. The present study documented cocaine-induced changes in brain metabolic activity as a function of cocaine self-administration history. Experimentally naive rhesus monkeys (N = 6) were given increasing access to cocaine under a fixed-ratio schedule of intravenous (i.v.) drug self-administration. PET imaging with F-18 labeled fluorodeoxyglucose (FDG) was used to measure acute intramuscular (i.m.) cocaine-induced changes in brain metabolism in the cocaine-naïve state, following 60 sessions under limited-access conditions (1 h/day), following 60 sessions under extended-access conditions (4 h/day), and following 4 weeks of drug withdrawal. In the cocaine-naïve state, cocaine-induced increases in brain metabolism were restricted to the prefrontal cortex. As cocaine exposure increased from limited to extended access, metabolic effects expanded throughout the frontal cortex and were induced within the striatum. Conversely, cocaine-induced activation was far less robust following withdrawal. The results highlight a progressive expansion of the metabolic effects of cocaine to include previously unaffected dopamine innervated brain regions as a consequence of cocaine self-administration history. The identification of brain regions progressively influenced by drug exposure may be highly relevant toward efforts to develop treatments for cocaine addiction. PMID:20680706

  6. The Compression Flow as a Measure to Estimate the Brain Connectivity Changes in Resting State fMRI and 18FDG-PET Alzheimer's Disease Connectomes.

    PubMed

    Zippo, Antonio G; Castiglioni, Isabella; Borsa, Virginia M; Biella, Gabriele E M

    2015-01-01

    The human brain appears organized in compartments characterized by seemingly specific functional purposes on many spatial scales. A complementary functional state binds information from specialized districts to return what is called integrated information. These fundamental network dynamics undergoes to severe disarrays in diverse degenerative conditions such as Alzheimer's Diseases (AD). The AD represents a multifarious syndrome characterized by structural, functional, and metabolic landmarks. In particular, in the early stages of AD, adaptive functional modifications of the brain networks mislead initial diagnoses because cognitive abilities may result indiscernible from normal subjects. As a matter of facts, current measures of functional integration fail to catch significant differences among normal, mild cognitive impairment (MCI) and even AD subjects. The aim of this work is to introduce a new topological feature called Compression Flow (CF) to finely estimate the extent of the functional integration in the brain networks. The method uses a Monte Carlo-like estimation of the information integration flows returning the compression ratio between the size of the injected information and the size of the condensed information within the network. We analyzed the resting state connectomes of 75 subjects of the Alzheimer's Disease Neuroimaging Initiative 2 (ADNI) repository. Our analyses are focused on the 18FGD-PET and functional MRI (fMRI) acquisitions in several clinical screening conditions. Results indicated that CF effectively discriminate MCI, AD and normal subjects by showing a significant decrease of the functional integration in the AD and MCI brain connectomes. This result did not emerge by using a set of common complex network statistics. Furthermore, CF was best correlated with individual clinical scoring scales. In conclusion, we presented a novel measure to quantify the functional integration that resulted efficient to discriminate different stages of

  7. Relationship between the expression level of SLA-DQA and Escherichia coli F18 infection in piglets.

    PubMed

    Bao, Wen-bin; Ye, Lan; Zi, Chen; Liu, Lu; Zhu, Jing; Pan, Zhang-yuan; Zhu, Guo-qiang; Huang, Xue-gen; Wu, Sheng-long

    2012-02-15

    The expression of SLA-DQA was assayed by Real-time PCR to analyze the differential expression between ETEC F18-resistant and -sensitive post-weaning piglets, and then to compare the expression levels of SLA-DQA in 11 different tissues from 8-, 18-, 30- and 35-day-old ETEC F18-resistant piglets, which aimed at discussing the role of SLA-DQA in resistance to ETEC F18. The results showed that SLA-DQA is broadly expressed in 11 tissues with the highest expression level in lymph nodes, and a relatively higher expression level in lung, spleen, jejunum, and duodenum. In tissues of lymph node, lung, spleen, jejunum, and duodenum, the mRNA expression of SLA-DQA in resistant individuals was significantly higher than that in sensitive ones (P<0.05). In most tissues, the expression of SLA-DQA increased from 8 to 18 and 30 days (weaning day), and increased persistently to 35 days of post-weaning. Expression levels of SLA-DQA on 35 days in most tissues were significant higher than that on 8, 18 and 30 days (P<0.05). The results demonstrated that the resistance to ETEC F18 in post-weaning piglets is related to up-regulation of mRNA expression of SLA-DQA to a certain extent. The analysis suggested that SLA-DQA may be not the direct immune factor that resisted the Escherichia coli F18, but perhaps enhanced humoral immunity and cell immunity to reduce the transmembrane signal transduction of ETEC F18 bacterial LPS and then led to the resistance to ETEC F18 in piglets.

  8. Utilization of the mouse large intestine to select an Escherichia coli F-18 DNA sequence that enhances colonizing ability and stimulates synthesis of type 1 fimbriae.

    PubMed Central

    Burghoff, R L; Pallesen, L; Krogfelt, K A; Newman, J V; Richardson, M; Bliss, J L; Laux, D C; Cohen, P S

    1993-01-01

    Escherichia coli F-18, a normal human fecal isolate, is an excellent colonizer of the streptomycin-treated mouse large intestine. E. coli F-18 Col-, a derivative of E. coli F-18 which no longer makes the E. coli F-18 colicin, colonizes the large intestine as well as E. coli F-18 when fed to mice alone but is eliminated when fed together with E. coli F-18. Random sequences of E. coli F-18 DNA were cloned into pRLB2, a par-B-stabilized derivative of pHC79. The entire gene library was transformed into E. coli F-18 Col- and fed to streptomycin-treated mice. The mouse large intestine selected a predominant clone which contained a recombinant plasmid (pRLB7) that enhanced E. coli F-18 Col- colonizing ability 100-fold but did not stimulate colicin synthesis. Moreover, pRLB7 simultaneously improved the survival of E. coli F-18 Col- in stationary phase in vitro, utilizing nutrients derived from mouse cecal mucus, and stimulated synthesis of both type 1 fimbriae and three E. coli F-18 Col- outer membrane proteins (74, 71, and 69 kDa). The 6.5-kb E. coli F-18 DNA sequence in pRLB7 does not contain either the fim operon or pilG (hns), both known to be involved in type 1 fimbrial synthesis. The sequence encodes six proteins, all smaller than the three E. coli F-18 Col- outer membrane proteins whose synthesis it stimulates. Collectively, the results suggest that the cloned E. coli F-18 DNA sequence contains one or more regulators of E. coli F-18 Col- operons expressed in the mouse large intestine in vivo and in isolated mouse cecal mucus in vitro. Images PMID:8095923

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

    SciTech Connect

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

    2008-05-01

    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.

  10. FDG-PET Contributions to the Pathophysiology of Memory Impairment.

    PubMed

    Segobin, Shailendra; La Joie, Renaud; Ritz, Ludivine; Beaunieux, Hélène; Desgranges, Béatrice; Chételat, Gaël; Pitel, Anne Lise; Eustache, Francis

    2015-09-01

    Measurement of synaptic activity by Positron Emission Tomography (PET) and its relation to cognitive functions such as episodic memory, working memory and executive functions in healthy humans and patients with neurocognitive disorders have been well documented. In this review, we introduce the concept of PET imaging that allows the observation of a particular biological process in vivo through the use of radio-labelled compounds, its general use to the medical world and its contributions to the understanding of memory systems. We then focus on [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG-PET), the radiotracer that is used to measure local cerebral metabolic rate of glucose that is indicative of synaptic activity in the brain. FDG-PET at rest has been at the forefront of functional neuroimaging over the past 3 decades, contributing to the understanding of cognitive functions in healthy humans and how these functional patterns change with cognitive alterations. We discuss methodological considerations that are important for optimizing FDG-PET imaging data prior to analysis. We then highlight the contribution of FDG-PET to the understanding of the patterns of functional differences in non-degenerative pathologies, normal ageing, and age-related neurodegenerative disorders. Through reasonable temporal and spatial resolution, its ability to measure synaptic activity in the whole brain, independently of any specific network and disease, makes it ideal to observe regional functional changes associated with memory impairment. PMID:26319237

  11. FDG-PET Contributions to the Pathophysiology of Memory Impairment.

    PubMed

    Segobin, Shailendra; La Joie, Renaud; Ritz, Ludivine; Beaunieux, Hélène; Desgranges, Béatrice; Chételat, Gaël; Pitel, Anne Lise; Eustache, Francis

    2015-09-01

    Measurement of synaptic activity by Positron Emission Tomography (PET) and its relation to cognitive functions such as episodic memory, working memory and executive functions in healthy humans and patients with neurocognitive disorders have been well documented. In this review, we introduce the concept of PET imaging that allows the observation of a particular biological process in vivo through the use of radio-labelled compounds, its general use to the medical world and its contributions to the understanding of memory systems. We then focus on [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG-PET), the radiotracer that is used to measure local cerebral metabolic rate of glucose that is indicative of synaptic activity in the brain. FDG-PET at rest has been at the forefront of functional neuroimaging over the past 3 decades, contributing to the understanding of cognitive functions in healthy humans and how these functional patterns change with cognitive alterations. We discuss methodological considerations that are important for optimizing FDG-PET imaging data prior to analysis. We then highlight the contribution of FDG-PET to the understanding of the patterns of functional differences in non-degenerative pathologies, normal ageing, and age-related neurodegenerative disorders. Through reasonable temporal and spatial resolution, its ability to measure synaptic activity in the whole brain, independently of any specific network and disease, makes it ideal to observe regional functional changes associated with memory impairment.

  12. Metabolic super scan in F-FDG PET/CT imaging.

    PubMed

    Kim, Dae-Weung; Kim, Chang Guhn; Park, Soon-Ah; Jung, Sang-Ah; Yang, Sei-Hoon

    2010-08-01

    A 50-yr-old man presented with intermittent hemoptysis and was diagnosed small cell lung cancer. (18)F-FDG PET/CT for staging demonstrated extensive hypermetabolic lesions throughout the skeleton and liver. Interestingly, skeletal muscles of limbs, mediastinum, bowel, and especially brain showed very low FDG uptake. Because of some characteristics in common with super scan on skeletal scintigraphy, this case could be considered as 'metabolic super scan'.

  13. F-18 deoxyglucose and stress N-13 ammonia positron emission tomography in anterior wall healed myocardial infarction

    SciTech Connect

    Fudo, T.; Kambara, H.; Hashimoto, T.; Hayashi, M.; Nohara, R.; Tamaki, N.; Yonekura, Y.; Senda, M.; Konishi, J.; Kawai, C.

    1988-06-01

    To evaluate myocardial blood flow and glucose utilization, N-13 ammonia (NH3) and F-18 deoxyglucose positron emission tomography scanning was performed in 22 patients with previous anterior wall myocardial infarction, using a high-resolution, multi-slice, whole-body scanner. The N-13 ammonia study was performed at rest and after exercise. The F-18 deoxyglucose study was performed at rest after fasting greater than 5 hours. The N-13 ammonia study revealed a hypoperfused area in 19 of the 22 patients (86%), that corresponded to the infarcted regions as diagnosed by electrocardiography, coronary arteriography and left ventriculography (21 patients). The hypoperfused areas expanded after exercise in 16 of 22 patients (73%). F-18 deoxyglucose uptake was observed in these hypoperfused areas, especially in patients with hypokinetic wall motion on left ventriculography and in exercise-induced hypoperfused areas. However, positron emission tomography demonstrated diffuse uptake of F-18 deoxyglucose in 3 of 8 patients with dyskinetic wall motion. Thus, metabolically active myocardium in infarcted areas or periinfarct ischemia can be visualized with F-18 deoxyglucose and stress N-13 ammonia studies.

  14. Zolpidem-Induced Arousal by Paradoxical GABAergic Stimulation: A Case Report With F-18 Flumazenil Positron Emission Tomography and Single Photon Emission Computed Tomography Study

    PubMed Central

    Kim, Changjae; Nam, Ki Yeun; Park, Jin Woo; Lee, Ho Jun

    2016-01-01

    Zolpidem is a non-benzodiazepine drug that has selectivity for the gamma-aminobutyric acid (GABA) receptors. We experienced paradoxical effect of zolpidem in a 48-year-old male patient with hypoxic-ischemic brain injury after cardiac arrest. The patient was in stupor and could not communicate. His Glasgow Coma Scale (GCS) was E2M4V2 and Rancho Los Amigos (RLA) was grade III to IV. Zolpidem was prescribed to induce sedation but paradoxically, he became alert (GCS 15, RLA VII) and was able to communicate. The arousal lasted for 2 hours repeatedly following each administration of the medication. While he was alert, electroencephalogram showed the reversal of slow wave into beta range fast activity and F-18 flumazenil positron emission tomography (PET) showed increased GABAergic receptor activity in both frontoparietotemporal cortices. Single photon emission computed tomography (SPECT) also showed increased cerebral perfusion and reversal of cerebellar diaschisis. PMID:26949686

  15. SU-E-J-258: Prediction of Cervical Cancer Treatment Response Using Radiomics Features Based On F18-FDG Uptake in PET Images

    SciTech Connect

    Altazi, B; Fernandez, D; Zhang, G; Biagioli, M; Moros, E; Moffitt, H. Lee

    2015-06-15

    Purpose: Radiomics have shown potential for predicting treatment outcomes in several body sites. This study investigated the correlation between PET Radiomics features and treatment response of cervical cancer outcomes. Methods: our dataset consisted of a cohort of 79 patients diagnosed with cervical cancer, FIGO stage IB-IVA, age range 25–86 years, (median age at diagnosis: 50 years) all treated between: 2009–14 with external beam radiation therapy to a dose range between: 45–50.4 Gy (median= 45 Gy), concurrent cisplatin chemotherapy and MRI-based brachytherapy to a dose of 20–30 Gy (median= 28 Gy). Metabolic Tumor Volume (MTV) in patient’s primary site was delineated on pretreatment PET/CT by two board certified Radiation Oncologists. The features extracted from each patient’s volume were: 26 Co-occurrence matrix (COM) Feature, 11 Run-Length Matrix (RLM), 11 Gray Level Size Zone Matrix (GLSZM) and 33 Intensity-based features (IBF). The treatment outcome was divided based on the last follow up status into three classes: No Evidence of Disease (NED), Alive with Disease (AWD) and Dead of Disease (DOD). The ability for the radiomics features to differentiate between the 3 treatments outcome categories were assessed by One-Way ANOVA test with p-value < 0.05 was to be statistically significant. The results from the analysis were compared with the ones obtained previously for standard Uptake Value (SUV). Results: Based on patients last clinical follow-up; 52 showed NED, 17 AWD and 10 DOD. Radiomics Features were able to classify the patients based on their treatment response. A parallel analysis was done for SUV measurements for comparison. Conclusion: Radiomics features were able to differentiate between the three different classes of treatment outcomes. However, most of the features were only able to differentiate between NED and DOD class. Also, The ability or radiomics features to differentiate types of response were more significant than SUV.

  16. SU-E-J-243: Reproducibility of Radiomics Features Through Different Voxel Discretization Levels in F18-FDG PET Images of Cervical Cancer

    SciTech Connect

    Altazi, B; Fernandez, D; Zhang, G; Biagioli, M; Moros, E; Moffitt, H. Lee

    2015-06-15

    Purpose: Site-specific investigations of the role of Radiomics in cancer diagnosis and therapy are needed. We report of the reproducibility of quantitative image features over different discrete voxel levels in PET/CT images of cervical cancer. Methods: Our dataset consisted of the pretreatment PET/CT scans from a cohort of 76 patients diagnosed with cervical cancer, FIGO stage IB-IVA, age range 31–76 years, treated with external beam radiation therapy to a dose range between 45–50.4 Gy (median dose: 45 Gy), concurrent cisplatin chemotherapy and MRI-based Brachytherapy to a dose of 20–30 Gy (median total dose: 28 Gy). Two board certified radiation oncologists delineated Metabolic Tumor volume (MTV) for each patient. Radiomics features were extracted based on 32, 64, 128 and 256 discretization levels (DL). The 64 level was chosen to be the reference DL. Features were calculated based on Co-occurrence (COM), Gray Level Size Zone (GLSZM) and Run-Length (RLM) matrices. Mean Percentage Differences (Δ) of features for discrete levels were determined. Normality distribution of Δ was tested using Kolomogorov - Smirnov test. Bland-Altman test was used to investigate differences between feature values measured on different DL. The mean, standard deviation and upper/lower value limits for each pair of DL were calculated. Interclass Correlation Coefficient (ICC) analysis was performed to examine the reliability of repeated measures within the context of the test re-test format. Results: 3 global and 5 regional features out of 48 features showed distribution not significantly different from a normal one. The reproducible features passed the normality test. Only 5 reproducible results were reliable, ICC range 0.7 – 0.99. Conclusion: Most of the radiomics features tested showed sensitivity to voxel level discretization between (32 – 256). Only 4 GLSZM, 3 COM and 1 RLM showed insensitivity towards mentioned discrete levels.

  17. Reciprocal Benefits of Mass-Univariate and Multivariate Modeling in Brain Mapping: Applications to Event-Related Functional MRI, H2 15O-, and FDG-PET

    PubMed Central

    Habeck, Christian G.

    2006-01-01

    In brain mapping studies of sensory, cognitive, and motor operations, specific waveforms of dynamic neural activity are predicted based on theoretical models of human information processing. For example in event-related functional MRI (fMRI), the general linear model (GLM) is employed in mass-univariate analyses to identify the regions whose dynamic activity closely matches the expected waveforms. By comparison multivariate analyses based on PCA or ICA provide greater flexibility in detecting spatiotemporal properties of experimental data that may strongly support alternative neuroscientific explanations. We investigated conjoint multivariate and mass-univariate analyses that combine the capabilities to (1) verify activation of neural machinery we already understand and (2) discover reliable signatures of new neural machinery. We examined combinations of GLM and PCA that recover latent neural signals (waveforms and footprints) with greater accuracy than either method alone. Comparative results are illustrated with analyses of real fMRI data, adding to Monte Carlo simulation support. PMID:23165047

  18. Evaluation of the dependence of the exposure dose on the attenuation correction in brain PET/CT scans using 18F-FDG

    NASA Astrophysics Data System (ADS)

    Choi, Eun-Jin; Jeong, Moon-Taeg; Jang, Seong-Joo; Choi, Nam-Gil; Han, Jae-Bok; Yang, Nam-Hee; Dong, Kyung-Rae; Chung, Woon-Kwan; Lee, Yun-Jong; Ryu, Young-Hwan; Choi, Sung-Hyun; Seong, Kyeong-Jeong

    2014-01-01

    This study examined whether scanning could be performed with minimum dose and minimum exposure to the patient after an attenuation correction. A Hoffman 3D Brain Phantom was used in BIO_40 and D_690 PET/CT scanners, and the CT dose for the equipment was classified as a low dose (minimum dose), medium dose (general dose for scanning) and high dose (dose with use of contrast medium) before obtaining the image at a fixed kilo-voltage-peak (kVp) and milliampere (mA) that were adjusted gradually in 17-20 stages. A PET image was then obtained to perform an attenuation correction based on an attenuation map before analyzing the dose difference. Depending on tube current in the range of 33-190 milliampere-second (mAs) when BIO_40 was used, a significant difference in the effective dose was observed between the minimum and the maximum mAs (p < 0.05). According to a Scheffe post-hoc test, the ratio of the minimum to the maximum of the effective dose was increased by approximately 5.26-fold. Depending on the change in the tube current in the range of 10-200 mA when D_690 was used, a significant difference in the effective dose was observed between the minimum and the maximum of mA (p < 0.05). The Scheffe posthoc test revealed a 20.5-fold difference. In conclusion, because effective exposure dose increases with increasing operating current, it is possible to reduce the exposure limit in a brain scan can be reduced if the CT dose can be minimized for a transmission scan.

  19. Altered leukotriene B4 metabolism in CYP4F18-deficient mice does not impact inflammation following renal ischemia.

    PubMed

    Winslow, Valeria; Vaivoda, Rachel; Vasilyev, Aleksandr; Dombkowski, David; Douaidy, Karim; Stark, Christopher; Drake, Justin; Guilliams, Evin; Choudhary, Dharamainder; Preffer, Frederic; Stoilov, Ivaylo; Christmas, Peter

    2014-06-01

    Inflammatory responses to infection and injury must be restrained and negatively regulated to minimize damage to host tissue. One proposed mechanism involves enzymatic inactivation of the pro-inflammatory mediator leukotriene B4, but it is difficult to dissect the roles of various metabolic enzymes and pathways. A primary candidate for a regulatory pathway is omega oxidation of leukotriene B4 in neutrophils, presumptively by CYP4F3A in humans and CYP4F18 in mice. This pathway generates ω, ω-1, and ω-2 hydroxylated products of leukotriene B4, depending on species. We created mouse models targeting exons 8 and 9 of the Cyp4f18 allele that allows both conventional and conditional knockouts of Cyp4f18. Neutrophils from wild-type mice convert leukotriene B4 to 19-hydroxy leukotriene B4, and to a lesser extent 18-hydroxy leukotriene B4, whereas these products were not detected in neutrophils from conventional Cyp4f18 knockouts. A mouse model of renal ischemia-reperfusion injury was used to investigate the consequences of loss of CYP4F18 in vivo. There were no significant changes in infiltration of neutrophils and other leukocytes into kidney tissue as determined by flow cytometry and immunohistochemistry, or renal injury as assessed by histological scoring and measurement of blood urea nitrogen. It is concluded that CYP4F18 is necessary for omega oxidation of leukotriene B4 in neutrophils, and is not compensated by other CYP enzymes, but loss of this metabolic pathway is not sufficient to impact inflammation and injury following renal ischemia-reperfusion in mice.

  20. Altered Leukotriene B4 metabolism in CYP4F18-deficient mice does not impact inflammation following renal ischemia

    PubMed Central

    Winslow, Valeria; Vaivoda, Rachel; Vasilyev, Aleksandr; Dombkowski, David; Douaidy, Karim; Stark, Christopher; Drake, Justin; Guilliams, Evin; Choudhary, Dharamainder; Preffer, Frederic; Stoilov, Ivaylo; Christmas, Peter

    2014-01-01

    Inflammatory responses to infection and injury must be restrained and negatively regulated to minimize damage to host tissue. One proposed mechanism involves enzymatic inactivation of the pro-inflammatory mediator leukotriene B4, but it is difficult to dissect the roles of various metabolic enzymes and pathways. A primary candidate for a regulatory pathway is omega oxidation of leukotriene B4 in neutrophils, presumptively by CYP4F3A in humans and CYP4F18 in mice. This pathway generates ω, ω-1, and ω-2 hydroxylated products of leukotriene B4, depending on species. We created mouse models targeting exons 8 and 9 of the Cyp4f18 allele that allows both conventional and conditional knockout of Cyp4f18. Neutrophils from wild-type mice convert leukotriene B4 to 19-hydroxy leukotriene B4, and to a lesser extent 18-hydroxy leukotriene B4, whereas these products were not detected in neutrophils from conventional Cyp4f18 knockouts. A mouse model of renal ischemia-reperfusion injury was used to investigate the consequences of loss of CYP4F18 in vivo. There were no significant changes in infiltration of neutrophils and other leukocytes into kidney tissue as determined by flow cytometry and immunohistochemistry, or renal injury as assessed by histological scoring and measurement of blood urea nitrogen. It is concluded that CYP4F18 is necessary for omega oxidation of leukotriene B4 in neutrophils, and is not compensated by other CYP enzymes, but loss of this metabolic pathway is not sufficient to impact inflammation and injury following renal ischemia-reperfusion in mice. PMID:24632148

  1. Radiation Dose from Whole-Body F-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Nationwide Survey in Korea

    PubMed Central

    2016-01-01

    The purpose of this study was to estimate average radiation exposure from 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) examinations and to analyze possible factors affecting the radiation dose. A nation-wide questionnaire survey was conducted involving all institutions that operate PET/CT scanners in Korea. From the response, radiation doses from injected FDG and CT examination were calculated. A total of 105 PET/CT scanners in 73 institutions were included in the analysis (response rate of 62.4%). The average FDG injected activity was 310 ± 77 MBq and 5.11 ± 1.19 MBq/kg. The average effective dose from FDG was estimated to be 5.89 ± 1.46 mSv. The average CT dose index and dose-length product were 4.60 ± 2.47 mGy and 429.2 ± 227.6 mGy∙cm, which corresponded to 6.26 ± 3.06 mSv. The radiation doses from FDG and CT were significantly lower in case of newer scanners than older ones (P < 0.001). Advanced PET technologies such as time-of-flight acquisition and point-spread function recovery were also related to low radiation dose (P < 0.001). In conclusion, the average radiation dose from FDG PET/CT is estimated to be 12.2 mSv. The radiation dose from FDG PET/CT is reduced with more recent scanners equipped with image-enhancing algorithms. PMID:26908992

  2. F-16XL and F-18 High Speed Acoustic Flight Test Databases

    NASA Technical Reports Server (NTRS)

    Kelly, J. J.; Wilson, M. R.; Rawls, J., Jr.; Norum, T. D.; Golub, R. A.

    1999-01-01

    This report presents the recorded acoustic data and the computed narrow-band and 1/3-octave band spectra produced by F-18 and F-16XL aircraft in subsonic flight over an acoustic array. Both broadband-shock noise and turbulent mixing noise are observed in the spectra. Radar and c-band tracking systems provided the aircraft position which enabled directivity and smear angles from the aircraft to each microphone to be computed. These angles are based on source emission time and thus give some idea about the directivity of the radiated sound field due to jet noise. A follow-on static test was also conducted where acoustic and engine data were obtained. The acoustic data described in the report has application to community noise analysis, noise source characterization and validation of prediction models. A detailed description of the signal processing procedures is provided. Follow-on static tests of each aircraft were also conducted for which engine data and far-field acoustic data are presented.

  3. Adaptive Flight Control Design with Optimal Control Modification on an F-18 Aircraft Model

    NASA Technical Reports Server (NTRS)

    Burken, John J.; Nguyen, Nhan T.; Griffin, Brian J.

    2010-01-01

    In the presence of large uncertainties, a control system needs to be able to adapt rapidly to regain performance. Fast adaptation is referred to as the implementation of adaptive control with a large adaptive gain to reduce the tracking error rapidly; however, a large adaptive gain can lead to high-frequency oscillations which can adversely affect the robustness of an adaptive control law. A new adaptive control modification is presented that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. The modification is based on the minimization of the Y2 norm of the tracking error, which is formulated as an optimal control problem. The optimality condition is used to derive the modification using the gradient method. The optimal control modification results in a stable adaptation and allows a large adaptive gain to be used for better tracking while providing sufficient robustness. A damping term (v) is added in the modification to increase damping as needed. Simulations were conducted on a damaged F-18 aircraft (McDonnell Douglas, now The Boeing Company, Chicago, Illinois) with both the standard baseline dynamic inversion controller and the adaptive optimal control modification technique. The results demonstrate the effectiveness of the proposed modification in tracking a reference model.

  4. Forebody Aerodynamics of the F-18 High Alpha Research Vehicle with Actuated Forebody Strakes

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Murri, Daniel G.

    2001-01-01

    Extensive pressure measurements and off-surface flow visualization were obtained on the forebody and strakes of the NASA F-18 High Alpha Research Vehicle (HARV) equipped with actuated forebody strakes. Forebody yawing moments were obtained by integrating the circumferential pressures on the forebody and strakes. Results show that large yawing moments can be generated with forebody strakes. At a 50 deg-angle-of-attack, deflecting one strake at a time resulted in a forebody yawing moment control reversal for small strake deflection angles. However, deflecting the strakes differentially about a 20 deg symmetric strake deployment eliminated the control reversal and produced a near linear variation of forebody yawing moment with differential strake deflection. At an angle of attack of 50 deg and for 0 deg and 20 deg symmetric strake deployments, a larger forebody yawing moment was generated by the forward fuselage (between the radome and the apex of the leading-edge extensions) than on the radome where the actuated forebody strakes were located. Cutouts on the flight vehicle strakes that were not on the wind tunnel models are believed to be responsible for deficits in the suction peaks on the flight radome pressure distributions and differences in the forebody yawing moments.

  5. Forebody Flow Visualization on the F-18 HARV with Actuated Forebody Strakes

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Murri, Daniel G.

    1998-01-01

    Off-surface smoke flow visualization and extensive pressure measurements were obtained on the forebody of the NASA F-18 High Alpha Research Vehicle equipped with actuated forebody strakes. Test points at alpha = 50 deg. were examined in which only one strake was deflected or in which both strakes were deflected differentially. The forebody pressures were integrated to obtain forebody yawing moments. Results showed that small single strake deflections can cause an undesirable yawing moment reversal. At alpha = 50 deg., this reversal was corrected by deploying both strakes at 20 deg. initially, then differentially from 20 deg. to create a yawing moment. The off-surface flow visualization showed that in the case of the small single strake deflection, the resulting forebody/strake vortex remained close to the surface and caused accelerated flow and increased suction pressures on the deflected side. When both strakes were deflected differentially, two forebody/strake vortices were present. The forebody/strake vortex from the larger deflection would lift from the surface while the other would remain close to the surface. The nearer forebody/strake vortex would cause greater flow acceleration, higher suction pressures and a yawing moment on that side of the forebody. Flow visualization provided a clear description of the strake vortices fluid mechanics.

  6. Flight-determined engine exhaust characteristics of an F404 engine in an F-18 airplane

    NASA Technical Reports Server (NTRS)

    Ennix, Kimberly A.; Burcham, Frank W., Jr.; Webb, Lannie D.

    1993-01-01

    Personnel at the NASA Langley Research Center (NASA-Langley) and the NASA Dryden Flight Research Facility (NASA-Dryden) recently completed a joint acoustic flight test program. Several types of aircraft with high nozzle pressure ratio engines were flown to satisfy a twofold objective. First, assessments were made of subsonic climb-to-cruise noise from flights conducted at varying altitudes in a Mach 0.30 to 0.90 range. Second, using data from flights conducted at constant altitude in a Mach 0.30 to 0.95 range, engineers obtained a high quality noise database. This database was desired to validate the Aircraft Noise Prediction Program and other system noise prediction codes. NASA-Dryden personnel analyzed the engine data from several aircraft that were flown in the test program to determine the exhaust characteristics. The analysis of the exhaust characteristics from the F-18 aircraft are reported. An overview of the flight test planning, instrumentation, test procedures, data analysis, engine modeling codes, and results are presented.

  7. The Potential Roles of 18F-FDG-PET in Management of Acute Stroke Patients

    PubMed Central

    Bunevicius, Adomas; Yuan, Hong

    2013-01-01

    Extensive efforts have recently been devoted to developing noninvasive imaging tools capable of delineating brain tissue viability (penumbra) during acute ischemic stroke. These efforts could have profound clinical implications for identifying patients who may benefit from tPA beyond the currently approved therapeutic time window and/or patients undergoing neuroendovascular treatments. To date, the DWI/PWI MRI and perfusion CT have received the most attention for identifying ischemic penumbra. However, their routine use in clinical settings remains limited. Preclinical and clinical PET studies with [18F]-fluoro-2-deoxy-D-glucose (18F-FDG) have consistently revealed a decreased 18F-FDG uptake in regions of presumed ischemic core. More importantly, an elevated 18F-FDG uptake in the peri-ischemic regions has been reported, potentially reflecting viable tissues. To this end, this paper provides a comprehensive review of the literature on the utilization of 14C-2-DG and 18F-FDG-PET in experimental as well as human stroke studies. Possible cellular mechanisms and physiological underpinnings attributed to the reported temporal and spatial uptake patterns of 18F-FDG are addressed. Given the wide availability of 18F-FDG in routine clinical settings, 18F-FDG PET may serve as an alternative, non-invasive tool to MRI and CT for the management of acute stroke patients. PMID:23762852

  8. Flight-Determined, Subsonic, Lateral-Directional Stability and Control Derivatives of the Thrust-Vectoring F-18 High Angle of Attack Research Vehicle (HARV), and Comparisons to the Basic F-18 and Predicted Derivatives

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Wang, Kon-Sheng Charles

    1999-01-01

    The subsonic, lateral-directional, stability and control derivatives of the thrust-vectoring F-1 8 High Angle of Attack Research Vehicle (HARV) are extracted from flight data using a maximum likelihood parameter identification technique. State noise is accounted for in the identification formulation and is used to model the uncommanded forcing functions caused by unsteady aerodynamics. Preprogrammed maneuvers provided independent control surface inputs, eliminating problems of identifiability related to correlations between the aircraft controls and states. The HARV derivatives are plotted as functions of angles of attack between 10deg and 70deg and compared to flight estimates from the basic F-18 aircraft and to predictions from ground and wind tunnel tests. Unlike maneuvers of the basic F-18 aircraft, the HARV maneuvers were very precise and repeatable, resulting in tightly clustered estimates with small uncertainty levels. Significant differences were found between flight and prediction; however, some of these differences may be attributed to differences in the range of sideslip or input amplitude over which a given derivative was evaluated, and to differences between the HARV external configuration and that of the basic F-18 aircraft, upon which most of the prediction was based. Some HARV derivative fairings have been adjusted using basic F-18 derivatives (with low uncertainties) to help account for differences in variable ranges and the lack of HARV maneuvers at certain angles of attack.

  9. 1/48-scale model of an F-18 aircraft in Flow Visualization Facility (FVF)

    NASA Technical Reports Server (NTRS)

    1980-01-01

    This short movie clip shows a plastic 1/48-scale model of an F-18 aircraft inside the 'Water Tunnel' more formally known as the NASA Dryden Flow Visualization Facility. Water is pumped through the tunnel in the direction of normal airflow over the aircraft; then, colored dyes are pumped through tubes with needle valves. The dyes flow back along the airframe and over the airfoils highlighting their aerodynamic characteristics. The aircraft can also be moved through its pitch axis to observe airflow disruptions while simulating actual flight at high angles of attack. The Water Tunnel at NASA's Dryden Flight Research Center, Edwards, CA, became operational in 1983 when Dryden was a Flight Research Facility under the management of the Ames Research Center in Mountain View, CA. As a medium for visualizing fluid flow, water has played a significant role. Its use dates back to Leonardo da Vinci (1452-1519), the Renaissance Italian engineer, architect, painter, and sculptor. In more recent times, water tunnels have assisted the study of complex flows and flow-field interactions on aircraft shapes that generate strong vortex flows. Flow visualization in water tunnels assists in determining the strength of vortices, their location, and possible methods of controlling them. The design of the Dryden Water Tunnel imitated that of the Northrop Corporation's tunnel in Hawthorne, CA. Called the Flow Visualization Facility, the Dryden tunnel was built to assist researchers in understanding the aerodynamics of aircraft configured in such a way that they create strong vortex flows, particularly at high angles of attack. The tunnel provides results that compare well with data from aircraft in actual flight in another fluid-air. Other uses of the tunnel have included study of how such flight hardware as antennas, probes, pylons, parachutes, and experimental fixtures affect airflow. The facility has also been helpful in finding the best locations for emitting smoke from flight vehicles

  10. 1/48-scale model of an F-18 aircraft in Flow Visualization Facility (FVF)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    This image shows a plastic 1/48-scale model of an F-18 aircraft inside the 'Water Tunnel' more formally known as the NASA Dryden Flow Visualization Facility. Water is pumped through the tunnel in the direction of normal airflow over the aircraft; then, colored dyes are pumped through tubes with needle valves. The dyes flow back along the airframe and over the airfoils highlighting their aerodynamic characteristics. The aircraft can also be moved through its pitch axis to observe airflow disruptions while simulating actual flight at high angles of attack. The Water Tunnel at NASA's Dryden Flight Research Center, Edwards, CA, became operational in 1983 when Dryden was a Flight Research Facility under the management of the Ames Research Center in Mountain View, CA. As a medium for visualizing fluid flow, water has played a significant role. Its use dates back to Leonardo da Vinci (1452-1519), the Renaissance Italian engineer, architect, painter, and sculptor. In more recent times, water tunnels have assisted the study of complex flows and flow-field interactions on aircraft shapes that generate strong vortex flows. Flow visualization in water tunnels assists in determining the strength of vortices, their location, and possible methods of controlling them. The design of the Dryden Water Tunnel imitated that of the Northrop Corporation's tunnel in Hawthorne, CA. Called the Flow Visualization Facility, the Dryden tunnel was built to assist researchers in understanding the aerodynamics of aircraft configured in such a way that they create strong vortex flows, particularly at high angles of attack. The tunnel provides results that compare well with data from aircraft in actual flight in another fluid-air. Other uses of the tunnel have included study of how such flight hardware as antennas, probes, pylons, parachutes, and experimental fixtures affect airflow. The facility has also been helpful in finding the best locations for emitting smoke from flight vehicles for flow

  11. Genome sequences and phylogenetic analysis of K88- and F18-positive porcine enterotoxigenic Escherichia coli.

    PubMed

    Shepard, Sara M; Danzeisen, Jessica L; Isaacson, Richard E; Seemann, Torsten; Achtman, Mark; Johnson, Timothy J

    2012-01-01

    Porcine enterotoxigenic Escherichia coli (ETEC) continues to result in major morbidity and mortality in the swine industry via postweaning diarrhea. The key virulence factors of ETEC strains, their serotypes, and their fimbrial components have been well studied. However, most studies to date have focused on plasmid-encoded traits related to colonization and toxin production, and the chromosomal backgrounds of these strains have been largely understudied. Here, we generated the genomic sequences of K88-positive and F18-positive porcine ETEC strains and examined the phylogenetic distribution of clinical porcine ETEC strains and their plasmid-associated genetic content. The genomes of porcine ETEC strains UMNK88 and UMNF18 were both found to contain remarkable plasmid complements containing known virulence factors, potential novel virulence factors, and antimicrobial resistance-associated elements. The chromosomes of these strains also possessed several unique genomic islands containing hypothetical genes with similarity to classical virulence factors, although phage-associated genomic islands dominated the accessory genomes of these strains. Phylogenetic analysis of 78 clinical isolates associated with neonatal and porcine diarrhea revealed that a limited subset of porcine ETEC lineages exist that generally contain common toxin and fimbrial profiles, with many of the isolates belonging to the ST10, ST23, and ST169 multilocus sequencing types. These lineages were generally distinct from existing human ETEC database isolates. Overall, most porcine ETEC strains appear to have emerged from a limited subset of E. coli lineages that either have an increased propensity to carry plasmid-encoded virulence factors or have the appropriate ETEC core genome required for virulence. PMID:22081385

  12. Screening for occult malignancy with FDG-PET/CT in patients with unprovoked venous thromboembolism.

    PubMed

    Alfonso, Ana; Redondo, Margarita; Rubio, Tomás; Del Olmo, Beatriz; Rodríguez-Wilhelmi, Pablo; García-Velloso, María J; Richter, José A; Páramo, José A; Lecumberri, Ramón

    2013-11-01

    Extensive screening strategies to detect occult cancer in patients with unprovoked venous thromboembolism (VTE) are complex and no benefit in terms of survival has been reported. FDG-PET/CT (2-[F-18] fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography), a noninvasive technique for the diagnosis and staging of malignancies, could be useful in this setting. Consecutive patients ≥ 50 years with a first unprovoked VTE episode were prospectively included. Screening with FDG-PET/CT was performed 3-4 weeks after the index event. If positive, appropriate diagnostic work-up was programmed. Clinical follow-up continued for 2 years. Blood samples were collected to assess coagulation biomarkers. FDG-PET/CT was negative in 68/99 patients (68.7%), while suspicious FDG uptake was detected in 31/99 patients (31.3%). Additional diagnostic work-up confirmed a malignancy in 7/31 patients (22.6%), with six of them at early stage. During follow-up, two patients with negative FDG-PET/CT were diagnosed with cancer. Sensitivity (S), positive (PPV) and negative predictive values (NPV) of FDG-PET/CT as single tool for the detection of occult malignancy were 77.8% (95% CI: 0.51-1), 22.6% (95% CI: 0.08-0.37) and 97.1% (95% CI: 0.93-1), respectively. Median tissue factor (TF) activity in patients with occult cancer was 5.38 pM vs. 2.40 pM in those without cancer (p = 0.03). Limitation of FDG-PET/CT screening to patients with TF activity > 2.8 pM would improve the PPV to 37.5% and reduce the costs of a single cancer diagnosis from 20,711€ to 11,670€. FDG-PET/CT is feasible for the screening of occult cancer in patients with unprovoked VTE, showing high S and NPV. The addition of TF activity determination may be useful for patient selection. PMID:23616232

  13. Molecular PET and PET/CT imaging of tumour cell proliferation using F-18 fluoro-L-thymidine: a comprehensive evaluation.

    PubMed

    Barwick, Tara; Bencherif, Badreddine; Mountz, James M; Avril, Norbert

    2009-12-01

    Positron emission tomography (PET) using F-18 fluoro-3'-deoxy-3-L-fluorothymidine (FLT) offers noninvasive assessment of cell proliferation in vivo. The most important application refers to the evaluation of tumour proliferative activity, representing a key feature of malignancy. Most data to date suggest that FLT is not a suitable biomarker for staging of cancers. This is because of the rather low fraction of tumour cells that undergo replication at a given time with subsequently relatively low tumour FLT uptake. In addition, generally, the high FLT uptake in liver and bone marrow limits the diagnostic use. We describe the current status on preclinical and clinical applications of FLT-PET including our own experience in brain tumours. The future of FLT-PET probably lies in the evaluation of tumour response to therapy and more importantly, in the prediction of early response in the course of treatment. The level of FLT accumulation in tumours depends on thymidine kinase 1 activity and on the therapy-induced activation of the salvage pathway and expression of nucleoside transporters. Therefore, cytostatic agents that cause arrest of the cell cycle in the S-phase may initially increase FLT uptake rather than reducing the tumour cell accumulation. In addition, agents that block the endogenous thymidine pathway may lead to overactivity of the salvage pathway and increase tumour FLT uptake. In contrast, many therapeutic agents inhibit both pathways and subsequently reduce tumour FLT uptake. Further studies comparing FLT with F-18 fluorodeoxyglucose-PET will be important to determine the complementary advantage of FLT-PET in early cancer therapy response assessment. Further research should be facilitated by simplified synthesis of FLT with improved yields and an increasing commercial availability.

  14. F18 Fluoromisonidazole for Imaging Tumor Hypoxia: Imaging the Microenvironment for Personalized Cancer Therapy

    PubMed Central

    Rajendran, JG; Krohn, KA

    2014-01-01

    Hypoxia in solid tumors is one of the seminal mechanisms for developing aggressive trait and treatment resistsance in solid tumors. This evolutionarily conserved biological mechanism along with de-repression of cellular functions in cancer, although resulting in many challenges, provide us with opportunities to use these adversities to our advantage. Our ability to use molecular imaging to characterize therapeutic targets such as hypoxia and apply this information for therapeutic interventions is growing rapidly. Evaluation of hypoxia and its biological ramifications to effectively plan appropriate therapy that can overcome the cure-limiting effects of hypoxia provides an objective means for treatment selection and planning. FMISO PET imaging of tumor hypoxia continues to be the lead radiopharmaceutical for the evaluation, prognostication and quantification of hypoxia, one of the key elements of the tumor microenvironment. FMISO is less confounded by blood flow and, although the images have less contrast than FDG PET, its uptake after 2 hours is an accurate reflection of inadequate regional Po2 at the time of radiopharmaceutical administration. By virtue of extensive clinical utilization, FMISO remains the lead candidate for imaging and quantifying hypoxia. The past decade has seen significant technological advances in investigating hypoxia imaging in radiation treatment planning and in providing us with the ability to individualize radiation delivery and target volume coverage. The presence of widespread hypoxia in the tumor can be effectively targeted with a systemic hypoxic cell cytotoxin or other agents that are more effective with diminished PO2, either alone or in combination. Molecular imaging in general and hypoxia imaging in particular will likely become an important in vivo imaging biomarker of the future, complementing the traditional direct tissue sampling methods by providing a snap shot of a primary tumor and metastatic disease and in following

  15. F-18 HARV yaw rate expansion flight #125 with Inverted Recovery

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's Dryden Flight Research Center, Edwards, CA, used an F-18 Hornet fighter aircraft as its High Angle-of-Attack (Alpha) Research Vehicle (HARV) in a three-phased flight research program lasting from April 1987 until September 1996. The aircraft completed 385 research flights and demonstrated stabilized flight at angles of attack between 65 and 70 degrees using thrust vectoring vanes, a research flight control system, and (eventually) forebody strakes (hinged structures on the forward side of the fuselage to provide control by interacting with vortices, generated at high angles of attack, to create side forces). This combination of technologies provided carefree handling of a fighter aircraft in a part of the flight regime that was otherwise very dangerous. Flight research with the HARV increased our understanding of flight at high angles of attack (angle of the wings with respect to the direction in which the aircraft was heading), enabling designers of U.S. fighter aircraft to design airplanes that will fly safely in portions of the flight envelope that pilots previously had to avoid. Flight 125 with the HARV involved yaw rate expansion up to 50 degrees per second (moving the nose to the left or right at that rate). NASA research pilot Ed Schneider was the pilot, and the purpose of the flight was to look at the spin characteristics of the HARV. The sequence in this particular video clip includes the first and second maneuvers in the flight. On the first maneuver, the pilot attempted to achieve a yaw rate of 40 degrees per second and actually went to 47 degrees. The spin was oscillatory in pitch (up and down) and roll (rotating around the longitudinal axis). Recovery was normal. On the second maneuver of the flight in which Schneider tried to achieve a yaw rate of 40 degrees per second, the aircraft overshot to 54 degrees per second during an oscillatory spin. In the course of the recovery, the aircraft rolled after a large sideslip buildup. Moderate aft stick

  16. Brain

    MedlinePlus

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  17. Dryden/Edwards 1994 Thrust-Vectoring Aircraft Fleet - F-18 HARV, X-31, F-16 MATV

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The three thrust-vectoring aircraft at Edwards, California, each capable of flying at extreme angles of attack, cruise over the California desert in formation during flight in March 1994. They are, from left, NASA's F-18 High Alpha Research Vehicle (HARV), flown by the NASA Dryden Flight Research Center; the X-31, flown by the X-31 International Test Organization (ITO) at Dryden; and the Air Force F-16 Multi-Axis Thrust Vectoring (MATV) aircraft. All three aircraft were flown in different programs and were developed independently. The NASA F-18 HARV was a testbed to produce aerodynamic data at high angles of attack to validate computer codes and wind tunnel research. The X-31 was used to study thrust vectoring to enhance close-in air combat maneuvering, while the F-16 MATV was a demonstration of how thrust vectoring could be applied to operational aircraft.

  18. Structural insight in histo-blood group binding by the F18 fimbrial adhesin FedF.

    PubMed

    Moonens, Kristof; Bouckaert, Julie; Coddens, Annelies; Tran, Thao; Panjikar, Santosh; De Kerpel, Maia; Cox, Eric; Remaut, Han; De Greve, Henri

    2012-10-01

    F18-positive enterotoxigenic and Shiga toxin-producing Escherichia coli are responsible for post-weaning diarrhoea and oedema disease in pigs and lead to severe production losses in the farming industry. F18 fimbriae attach to the small intestine of young piglets by latching onto glycosphingolipids with A/H blood group determinants on type 1 core. We demonstrate the N-terminal domain of the F18 fimbrial subunit FedF to be responsible for ABH-mediated attachment and present its X-ray structure in ligand-free form and bound to A and B type 1 hexaoses. The FedF lectin domain comprises a 10-stranded immunoglobulin-like β-sandwich. Three linear motives, Q(47) -N(50), H(88) -S(90) and R(117) -T(119), form a shallow glycan binding pocket near the tip of the domain that is selective for type 1 core glycans in extended conformation. In addition to the glycan binding pocket, a polybasic loop on the membrane proximal surface of FedF lectin domain is shown to be required for binding to piglet enterocytes. Although dispensable for ABH glycan recognition, the polybasic surface adds binding affinity in the context of the host cell membrane, a mechanism that is proposed to direct ABH-glycan binding to cell-bound glycosphingolipids and could allow bacteria to avoid clearance by secreted glycoproteins. PMID:22812428

  19. Surface flow visualization of separated flows on the forebody of an F-18 aircraft and wind-tunnel model

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Richwine, David M.; Banks, Daniel W.

    1988-01-01

    A method of in-flight surface flow visualization similar to wind-tunnel-model oil flows is described for cases where photo-chase planes or onboard photography are not practical. This method, used on an F-18 aircraft in flight at high angles of attack, clearly showed surface flow streamlines in the fuselage forebody. Vortex separation and reattachment lines were identified with this method and documented using postflight photography. Surface flow angles measured at the 90 and 270 degrees meridians show excellent agreement with the wind tunnel data for a pointed tangent ogive with an aspect ratio of 3.5. The separation and reattachment line locations were qualitatively similar to the F-18 wind-tunnel-model oil flows but neither the laminar separation bubble nor the boundary-layer transition on the wind tunnel model were evident in the flight surface flows. The separation and reattachment line locations were in fair agreement with the wind tunnel data for the 3.5 ogive. The elliptical forebody shape of the F-18 caused the primary separation lines to move toward the leeward meridian. Little effect of angle of attack on the separation locations was noted for the range reported.

  20. Wilson's disease studied with FDG and positron emission tomography

    SciTech Connect

    Hawkins, R.A.; Mazziotta, J.C.; Phelps, M.E.

    1987-11-01

    Four patients with Wilson's disease and eight normal controls were studied with 2-deoxy-2-(/sup 18/F)fluoro-D-glucose (FDG) and positron emission tomography (PET). The patients had diffusely reduced glucose metabolism in all brain regions evaluated compared with controls, with the exception of the thalamus. The ratio of the cerebral metabolic rate for glucose in the lenticular nuclei to hemispheres declined from 1.23 (+/- 0.14 SD) in controls to 1.03 (+/- 0.06) (p less than 0.025) in Wilson's disease patients. Compared with Huntington's disease, the PET FDG results in Wilson's disease indicate relatively less focal involvement of the caudate nucleus, more severe focal changes in the lenticular nuclei, and more significant global changes in glucose metabolism.

  1. Radiosynthesis binding affinity and biodistribution of 3-[F-18]fluoro-N-({alpha},{alpha},{alpha}-trifluoro-m-tolyl)piperazine (FTFMPP), a radioligand for the Serotonin system

    SciTech Connect

    Mishani, E.; Cristel, M.E.; McCarthy, T.J.; Welch, M.J.

    1996-05-01

    The serotonin agonist N({alpha},{alpha},{alpha}-trifluoro-m-tolyl)piperazine (TFMPP) is a potent ligand for the serotonin system. Angelini and co-workers previously synthesized the c.a [F-18]TFMPP but the low specific activity (less than 0.2GBq/mmol) limited the application of this ligand. We have recently reported the formation of phenylpiperazines by a novel alumina supported bis-alkylation. We report the application of this method and biological evaluation of 3-[F-18]FTFMPP, a fluoro derivative of TFMPP. Reaction of [F-18]fluoride with 3,5-dinitrobenzotrifluoride gave the 3-[F-18]fluoro-5-nitrobenzotrifluoride in 70% yield. Reduction of the nitro group with Raney nickel and hydrazine hydrate gave the [F-18]aniline derivative in 70% yield. Finally, the phenylpiperazine was constructed by reaction of the [F-18]aniline derivative with bis-2-bromoethyl-N-(ethoxy carbonyl)amine on basic alumina (pH=9) as a solid support. After extraction of the activity with basic MeOH and HPLC purification on normal phase the final product- [F-18]FTFMPP was obtained in 50% yield (98% radiochemical purity). The specific activity of the final product was 100GBq/mmol. The binding affinity of FTFMPP to 5-HT receptor was determined (Ki = 80-100 nM) and found to be similar to the binding affinity of the TFMPP (160-180 nM). The biodistribution of [F-18]FTFMPP was performed in rats.

  2. FDG-PET/CT and CT Findings of a Benign Solitary Fibrous Tumor of the Kidney; Correlation with Pathology.

    PubMed

    Nakajima, Reiko; Abe, Koichiro; Kondo, Tsunenori; Nagashima, Yoji; Kimura, Ken; Fukushima, Kenji; Momose, Mitsuru; Kondo, Chisato; Tanabe, Kazunari; Sakai, Shuji

    2015-01-01

    Herein, we report the F-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) findings of a benign solitary fibrous tumor (SFT) of the kidney. The patient was a 63-year-old woman with a mass in the right kidney (10×9.7 cm), incidentally found on CT images. The CT scan showed a lobulated tumor arising from the hilum of the right kidney. The tumor consisted of two components with different patterns of enhancement. Most of the tumor demonstrated moderate enhancement from the corticomedullary to nephrographic phase. A small nodular component at the caudal portion of the tumor showed avid enhancement in the corticomedullary phase and rapid washout in the nephrographic phase in contrast-enhanced CT. FDG-PET/CT was performed and showed weak FDG accumulation (SUVmax=2.30 and 1.91 in the main and small caudal components). Although renal cell carcinoma was preoperatively diagnosed, histopathological examination revealed renal SFT, with no malignant potential. Therefore, when a renal tumor with contrast-medium enhancement and low FDG accumulation is demonstrated, SFT should be considered as a differential diagnosis in addition to renal cell carcinoma. PMID:27408891

  3. FDG-PET/CT and CT Findings of a Benign Solitary Fibrous Tumor of the Kidney; Correlation with Pathology.

    PubMed

    Nakajima, Reiko; Abe, Koichiro; Kondo, Tsunenori; Nagashima, Yoji; Kimura, Ken; Fukushima, Kenji; Momose, Mitsuru; Kondo, Chisato; Tanabe, Kazunari; Sakai, Shuji

    2015-01-01

    Herein, we report the F-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) findings of a benign solitary fibrous tumor (SFT) of the kidney. The patient was a 63-year-old woman with a mass in the right kidney (10×9.7 cm), incidentally found on CT images. The CT scan showed a lobulated tumor arising from the hilum of the right kidney. The tumor consisted of two components with different patterns of enhancement. Most of the tumor demonstrated moderate enhancement from the corticomedullary to nephrographic phase. A small nodular component at the caudal portion of the tumor showed avid enhancement in the corticomedullary phase and rapid washout in the nephrographic phase in contrast-enhanced CT. FDG-PET/CT was performed and showed weak FDG accumulation (SUVmax=2.30 and 1.91 in the main and small caudal components). Although renal cell carcinoma was preoperatively diagnosed, histopathological examination revealed renal SFT, with no malignant potential. Therefore, when a renal tumor with contrast-medium enhancement and low FDG accumulation is demonstrated, SFT should be considered as a differential diagnosis in addition to renal cell carcinoma.

  4. FDG-PET/CT and CT Findings of a Benign Solitary Fibrous Tumor of the Kidney; Correlation with Pathology

    PubMed Central

    Nakajima, Reiko; Abe, Koichiro; Kondo, Tsunenori; Nagashima, Yoji; Kimura, Ken; Fukushima, Kenji; Momose, Mitsuru; Kondo, Chisato; Tanabe, Kazunari; Sakai, Shuji

    2015-01-01

    Herein, we report the F-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) findings of a benign solitary fibrous tumor (SFT) of the kidney. The patient was a 63-year-old woman with a mass in the right kidney (10×9.7 cm), incidentally found on CT images. The CT scan showed a lobulated tumor arising from the hilum of the right kidney. The tumor consisted of two components with different patterns of enhancement. Most of the tumor demonstrated moderate enhancement from the corticomedullary to nephrographic phase. A small nodular component at the caudal portion of the tumor showed avid enhancement in the corticomedullary phase and rapid washout in the nephrographic phase in contrast-enhanced CT. FDG-PET/CT was performed and showed weak FDG accumulation (SUVmax=2.30 and 1.91 in the main and small caudal components). Although renal cell carcinoma was preoperatively diagnosed, histopathological examination revealed renal SFT, with no malignant potential. Therefore, when a renal tumor with contrast-medium enhancement and low FDG accumulation is demonstrated, SFT should be considered as a differential diagnosis in addition to renal cell carcinoma. PMID:27408891

  5. KEY COMPARISON: Comparisons CCRI(II)-K3.F-18 and APMP.RI(II)-K3.F-18 of activity measurements of the radionuclide 18F and links to the key comparison reference value of the BIPM.RI(II)-K1.F-18 comparison

    NASA Astrophysics Data System (ADS)

    Ratel, G.; Michotte, C.; Woods, M. J.

    2005-01-01

    In 2003, the CCRI(II) decided that an indirect comparison of 18F measurements piloted by the National Physical Laboratory (NPL), UK in 2001 was sufficiently well constructed that it could be converted into a CCRI(II) comparison, with comparison identifier CCRI(II)-K3.F-18. At the same time, the pilot laboratory made a bilateral comparison with the institute in Chinese Taipei, comparison identifier APMP.RI(II)-K3.F-18. The results of the comparisons have been reported and the key comparison working group (KCWG) of the CCRI(II) has approved the mechanism to link all the results to the key comparison reference value (KCRV) of 18F. The KCRV has been determined through the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.F-18. These comparisons have enabled a further four results to be added to the matrix of degrees of equivalence for 18F activity measurements. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).

  6. Functional brain abnormalities localized in 55 chronic tinnitus patients: fusion of SPECT coincidence imaging and MRI

    PubMed Central

    Farhadi, Mohammad; Mahmoudian, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaee, Mohammad; Ahmadizadeh, Majid; Ghasemikian, Khosro; Gholami, Saeid; Ghoreyshi, Esmaeel; Beyty, Saeid; Shamshiri, Ahmadreza; Madani, Sedighe; Bakaev, Valery; Moradkhani, Seddighe; Raeisali, Gholamreza

    2010-01-01

    Tinnitus is often defined as the perception of sounds or noise in the absence of any external auditory stimuli. The pathophysiology of subjective idiopathic tinnitus remains unclear. The aim of this study was to investigate the functional brain activities and possible involved cerebral areas in subjective idiopathic tinnitus patients by means of single photon emission computerized tomography (SPECT) coincidence imaging, which was fused with magnetic resonance imaging (MRI). In this cross-sectional study, 56 patients (1 subject excluded) with subjective tinnitus and 8 healthy controls were enrolled. After intravenous injection of 5 mCi F18-FDG (fluorodeoxyglucose), all subjects underwent a brain SPECT coincidence scan, which was then superimposed on their MRIs. In the eight regions of interest (middle temporal, inferotemporal, medial temporal, lateral temporal, temporoparietal, frontal, frontoparietal, and parietal areas), the more pronounced values were represented in medial temporal, inferotemporal, and temporoparietal areas, which showed more important proportion of associative auditory cortices in functional attributions of tinnitus than primary auditory cortex. Brain coincidence SPECT scan, when fused on MRI is a valuable technique in the assessment of patients with tinnitus and could show the significant role of different regions of central nervous system in functional attributions of tinnitus. PMID:20068582

  7. Functional brain abnormalities localized in 55 chronic tinnitus patients: fusion of SPECT coincidence imaging and MRI.

    PubMed

    Farhadi, Mohammad; Mahmoudian, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaee, Mohammad; Ahmadizadeh, Majid; Ghasemikian, Khosro; Gholami, Saeid; Ghoreyshi, Esmaeel; Beyty, Saeid; Shamshiri, Ahmadreza; Madani, Sedighe; Bakaev, Valery; Moradkhani, Seddighe; Raeisali, Gholamreza

    2010-04-01

    Tinnitus is often defined as the perception of sounds or noise in the absence of any external auditory stimuli. The pathophysiology of subjective idiopathic tinnitus remains unclear. The aim of this study was to investigate the functional brain activities and possible involved cerebral areas in subjective idiopathic tinnitus patients by means of single photon emission computerized tomography (SPECT) coincidence imaging, which was fused with magnetic resonance imaging (MRI). In this cross-sectional study, 56 patients (1 subject excluded) with subjective tinnitus and 8 healthy controls were enrolled. After intravenous injection of 5 mCi F18-FDG (fluorodeoxyglucose), all subjects underwent a brain SPECT coincidence scan, which was then superimposed on their MRIs. In the eight regions of interest (middle temporal, inferotemporal, medial temporal, lateral temporal, temporoparietal, frontal, frontoparietal, and parietal areas), the more pronounced values were represented in medial temporal, inferotemporal, and temporoparietal areas, which showed more important proportion of associative auditory cortices in functional attributions of tinnitus than primary auditory cortex. Brain coincidence SPECT scan, when fused on MRI is a valuable technique in the assessment of patients with tinnitus and could show the significant role of different regions of central nervous system in functional attributions of tinnitus.

  8. SR-71B - in Flight with F-18 Chase Aircraft - View from Air Force Tanker

    NASA Technical Reports Server (NTRS)

    1996-01-01

    NASA 831, an SR-71B operated by the Dryden Flight Research Center, Edwards, California, cruises over the Mojave Desert with an F/A-18 Hornet flying safety chase. They were photographed on a 1996 mission from an Air Force refueling tanker The F/A-18 Hornet is used primarily as a safety chase and support aircraft at Dryden. As support aircraft, the F-18s are used for safety chase, pilot proficiency and aerial photography. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used

  9. CD14 in the TLRs signaling pathway is associated with the resistance to E. coli F18 in Chinese domestic weaned piglets

    PubMed Central

    Wu, Zhengchang; Liu, Ying; Dong, Wenhua; Zhu, Guo-qiang; Wu, Shenglong; Bao, Wenbin

    2016-01-01

    Escherichia coli F18 (E. coli F18) is mainly responsible for post-weaning diarrhea (PWD) in piglets. The genetic basis and regulatory mechanism of E. coli F18 resistance in Chinese domestic weaned piglets remain unclear. Meishan piglets were used as model animals to test their susceptibility to E. coli F18. By performing a comparative transcriptome study on duodenum tissues of sensitive and resistant pigs, we identified 198 differentially expressed genes (DEGs; 125 upregulated and 73 downregulated) in the resistant pigs. DEGs were predominately involved in immune system pathways, including the Toll-like receptor (TLR) signaling pathway. qPCR and western blot showed CD14, IFN-α, TLR4 and IL-1β, etc. in the TLR signaling pathway had significantly higher expression levels in lipopolysaccharide (LPS)-induced small intestinal epithelial cell lines (IPEC-J2) than those in normal IPEC-J2 cells. Immunohistochemical analysis showed the increased expression of CD14 gene in the E. coli F18-resistant individuals. After CD14 knockdown, the levels of cytokines IL-6 and IL-12 were significantly reduced in IPEC-J2 cell supernatants. The adhesion ability of F18ab strain with IPEC-J2 cells was significantly increased (p < 0.01). This study revealed the TLR signaling pathway, and especially CD14, probably plays an important role in resistance to E. coli F18 infection in Chinese domestic piglets. PMID:27098998

  10. CD14 in the TLRs signaling pathway is associated with the resistance to E. coli F18 in Chinese domestic weaned piglets.

    PubMed

    Wu, Zhengchang; Liu, Ying; Dong, Wenhua; Zhu, Guo-qiang; Wu, Shenglong; Bao, Wenbin

    2016-01-01

    Escherichia coli F18 (E. coli F18) is mainly responsible for post-weaning diarrhea (PWD) in piglets. The genetic basis and regulatory mechanism of E. coli F18 resistance in Chinese domestic weaned piglets remain unclear. Meishan piglets were used as model animals to test their susceptibility to E. coli F18. By performing a comparative transcriptome study on duodenum tissues of sensitive and resistant pigs, we identified 198 differentially expressed genes (DEGs; 125 upregulated and 73 downregulated) in the resistant pigs. DEGs were predominately involved in immune system pathways, including the Toll-like receptor (TLR) signaling pathway. qPCR and western blot showed CD14, IFN-α, TLR4 and IL-1β, etc. in the TLR signaling pathway had significantly higher expression levels in lipopolysaccharide (LPS)-induced small intestinal epithelial cell lines (IPEC-J2) than those in normal IPEC-J2 cells. Immunohistochemical analysis showed the increased expression of CD14 gene in the E. coli F18-resistant individuals. After CD14 knockdown, the levels of cytokines IL-6 and IL-12 were significantly reduced in IPEC-J2 cell supernatants. The adhesion ability of F18ab strain with IPEC-J2 cells was significantly increased (p < 0.01). This study revealed the TLR signaling pathway, and especially CD14, probably plays an important role in resistance to E. coli F18 infection in Chinese domestic piglets.

  11. Free-to-roll tests of X-31 and F-18 subscale models with correlation to flight test results

    NASA Technical Reports Server (NTRS)

    Williams, David L., II; Nelson, Robert C.; Fisher, David F.

    1994-01-01

    This presentation will concentrate on a series of low-speed wind tunnel tests conducted on a 2.5 percent subscale F-18 model and a 2 percent subscale X-31 model. The model's control surfaces were unaugmented; and for the most part, were deflected at a constant angle throughout the tests. The tests consisted mostly of free-to-roll experiments conducted with the use of an air-bearing, surface pressure measurements, off-surface flow visualization, and force-balance tests. Where possible the results of the subscale tests have been compared to flight test data, or to other wind tunnel data taken at higher Reynolds numbers.

  12. Calcified peritoneal metastasis identified on 18F-fluoride positron emission tomography/computed tomography: Importance of extraosseous uptake of F-18 fluoride

    PubMed Central

    Verma, Priyanka; Chandra, Piyush; Agrawal, Archi; Purandare, Nilendu; Shah, Sneha; Rangarajan, Venkatesh

    2016-01-01

    F-18 NaF positron emission tomography/computed tomography (PET/CT) is used for the evaluation of malignant and nonmalignant osseous disease. Extraosseous uptake of 18 fluoride-NaF has been observed in the arterial vasculature, gastrointestinal tract, and genitourinary tract. We describe a case of a woman with carcinoma of unknown primary in whom F-18 NaF PET/CT showed tracer uptake in the calcified peritoneal metastasis. Extraosseous findings on F-18 NaF PET/CT, though rare, may be visualized and may result in important management changes. PMID:27095869

  13. FDG-PET/CT is a pivotal imaging modality to diagnose rare intravascular large B-cell lymphoma: case report and review of literature.

    PubMed

    Colavolpe, Cecile; Ebbo, Mikael; Trousse, Delphine; Khibri, Hajar; Franques, Jerome; Chetaille, Bruno; Coso, Diane; Ouvrier, Matthieu John; Gastaud, Lauris; Guedj, Eric; Schleinitz, Nicolas

    2015-06-01

    Intravascular large B-cell lymphoma (IVLBCL) remains a diagnostic challenge, because of non-specific findings on clinical, laboratory, and imaging studies. We present a case in which 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography was particularly useful to suspect the diagnosis, to detect unexpected locations, to guide contributive biopsy, and to assess the response to treatment. In case of initial negative results, FDG-PET should be repeated in the course of clinical evolution. In the presence of neurological or hormonal symptoms without brain magnetic resonance imaging abnormality, FDG-PET brain slices could depict additional pituitary and/or brain hypermetabolisms. We discuss the potential interests of FDG-PET in IVLBCL by a literature review.

  14. Serial FDG PET/CT in autoimmune encephalitis with faciobrachial dystonic seizures.

    PubMed

    Kunze, Albrecht; Drescher, Robert; Kaiser, Katharina; Freesmeyer, Martin; Witte, Otto W; Axer, Hubertus

    2014-10-01

    Autoimmune encephalitis (AE) is increasingly recognized as a nonparaneoplastic disorder with autoantibodies to neuronal proteins. Although MRI is frequently unremarkable, PET imaging might contribute to identification of affected brain regions in distinct AE. We report on serial FDG PET in a 72-year-old man with particular AE subtype, with potassium channel complex antibodies and prodromal stage with dystonic seizures. Serial FDG PET/CT revealed that besides limbic structures, basal ganglia are centrally involved and presumably play a key role in the generation of dystonic seizures.

  15. Serial 18F-FDG PET/CT Findings in a Patient With IgLON5 Encephalopathy.

    PubMed

    Zhang, Wei; Niu, Na; Cui, Ruixue

    2016-10-01

    We presented the serial FDG PET/CT brain scans of a 64-year-old woman with IgLON5 encephalopathy, which is a novel syndrome in association with antibodies to a neuronal cell adhesion protein named IgLON5, and FDG PET findings have not been characterized previously. For our case, the relatively hypermetabolism in primary sensorimotor cortices, basal ganglia, and cerebrum comparing to other cortical regions on the pretreatment FDG PET/CT was partially recovered on the follow-up FDG PET/CT scan after immunotherapy, corresponding with the alleviation of clinical syndromes. The metabolic change pattern was not similar as other types of autoimmune encephalitis. PMID:27556794

  16. Dryden Research Aircraft Fleet on Ramp - 1993, X-15, F-18, SR-71, X-31, X-29

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A group photo of research aircraft at NASA's Ames/Dryden Flight Research Facility in 1993 (redesignated the Dryden Flight Research Center in 1994). Left to right: mock-up of X-15, F-18B, SR-71A, X-31, and X-29. The X-15 mock-up is painted as the #3 aircraft, which was lost on November 15, 1967, in an accident that resulted in the death of Air Force Major Mike Adams. The mock-up is now (2001) atop a pole in front of Dryden's main gate. The two-seat F-18B was in use around the turn of the 20th into the 21st century as a chase aircraft for a variety of projects. The SR-71 was one of several transferred to NASA after the aircraft was retired by the Air Force. The X-31 was designed to test flight at high angles of attack using thrust vectoring. The X-29 served as a testbed for forward swept wings. These aircraft and mock-up suggest the great variety of flight research that Dryden Flight Research Center and its predecessor organizations have conducted over more than 50 years since 1946.

  17. A prospective trial comparing FDG-PET/CT and CT to assess tumor response to cetuximab in patients with incurable squamous cell carcinoma of the head and neck

    PubMed Central

    Adkins, Douglas; Ley, Jessica; Dehdashti, Farrokh; Siegel, Marilyn J; Wildes, Tanya M; Michel, Loren; Trinkaus, Kathryn; Siegel, Barry A

    2014-01-01

    Computed tomography (CT), the standard method to assess tumor response to cetuximab in incurable squamous cell carcinoma of the head and neck (SCCHN), performs poorly as judged by the disparity between high disease control rate (46%) and short time to progression (TTP) (70 days). F-18 fluorodeoxyglucose positron emission tomography (FDG-PET)/CT is an alternative method to assess tumor response. The primary objective of this prospective trial was to evaluate the metabolic response of target lesions, assessed as the change in maximum standardized uptake value (SUVmax) on FDG-PET/CT before and after 8 weeks (cycle 1) of cetuximab. Secondary objectives were to compare tumor response by CT (RECIST 1.0) and FDG-PET/CT (EORTC criteria) following cycle 1, and determine TTP with continued cetuximab administration in patients with disease control by CT after cycle 1 but stratified for disease control or progression by FDG-PET/CT. Among 27 patients, the mean percent change of SUVmax of target lesions after cycle 1 was −21% (range: +72% to −81%); by FDG-PET/CT, partial response (PR)/stable disease (SD) occurred in 15 patients (56%) and progression in 12 (44%), whereas by CT, PR/SD occurred in 20 (74%) and progression in 7 (26%). FDG-PET/CT and CT assessments were discordant in 14 patients (P = 0.0029) and had low agreement (κ = 0.30; 95% confidence interval [CI]: 0.12, 0.48). With disease control by CT after cycle 1, median TTP was 166 days (CI: 86, 217) if the FDG-PET/CT showed disease control and 105 days (CI: 66, 159) if the FDG-PET/CT showed progression (P < 0.0001). Median TTP of the seven patients whose post cycle 1 CT showed progression compared to the 12 whose FDG-PET/CT showed progression were similar (53 [CI: 49, 56] vs. 61 [CI: 50, 105] days, respectively). FDG-PET/CT may be better than CT in assessing benefit of cetuximab in incurable SCCHN. PMID:25081631

  18. Cerebral arterial inflow assessment with 18F-FDG PET: methodology and feasibility.

    PubMed

    Benathan-Tordjmann, Jennifer; Bailly, Pascal; Meyer, Marc-Etienne; Daouk, Joël

    2014-10-01

    Positron emission tomography (PET) with 18fluorodeoxyglucose (18F-FDG) is increasingly used in neurology. The measurement of cerebral arterial inflow (QA) using 18F-FDG complements the information provided by standard brain PET imaging. Here, injections were performed after the beginning of dynamic acquisitions and the time to arrival (t0) of activity in the gantry's field of view was computed. We performed a phantom study using a branched tube (internal diameter: 4mm) and a 18F-FDG solution injected at 240 mL/min. Data processing consisted of (i) reconstruction of the first 3s after t0, (ii) vascular signal enhancement and (iii) clustering. This method was then applied in four subjects. We measured the volumes of the tubes or vascular trees and calculated the corresponding flows. In the phantom, the flow was calculated to be 244.2 mL/min. In each subject, our QA value was compared with that obtained by quantitative cine-phase contrast magnetic resonance imaging; the mean QA value of 581.4±217.5 mL/min calculated with 18F-FDG PET was consistent with the mean value of 593.3±205.8 mL/min calculated with quantitative cine-phase contrast magnetic resonance imaging. Our 18F-FDG PET method constitutes a novel, fully automatic means of measuring QA.

  19. Brain (18)F-FDG, (18)F-Florbetaben PET/CT, (123)I-FP-CIT SPECT and Cardiac (123)I-MIBG Imaging for Diagnosis of a "Cerebral Type" of Lewy Body Disease.

    PubMed

    Van Der Gucht, Axel; Cleret de Langavant, Laurent; Bélissant, Ophélie; Rabu, Corentin; Cottereau, Anne-Ségolène; Evangelista, Eva; Chalaye, Julia; Bonnot-Lours, Sophie; Fénelon, Gilles; Itti, Emmanuel

    2016-09-01

    A 67-year-old man was referred for fluctuating neuropsychiatric symptoms, featuring depression, delirious episodes, recurrent visual hallucinations and catatonic syndrome associated with cognitive decline. No parkinsonism was found clinically even under neuroleptic treatment. (18)F-FDG PET/CT showed hypometabolism in the posterior associative cortex including the occipital cortex, suggesting Lewy body dementia, but (123)I-FP-CIT SPECT was normal and cardiac (123)I-MIBG imaging showed no signs of sympathetic denervation. Alzheimer's disease was excluded by a normal (18)F-florbetaben PET/CT. This report suggests a rare case of α-synucleinopathy without brainstem involvement, referred to as "cerebral type" of Lewy body disease. PMID:27540431

  20. In-flight flow visualization and pressure measurements at low speeds on the NASA F-18 high alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Delfrate, John H.; Fisher, David F.; Zuniga, Fanny A.

    1991-01-01

    Inflight results from surface and off surface flow visualizations and from extensive pressure distributions document the vortical flow on the leading edge extensions (LEXs) and forebody of the NASA F-18 high alpha research vehicle (HARV) for low speeds and angles of attack up to 50 deg. Surface flow visualization data, obtained using the emitted fluid technique, were used to define separation lines and laminar separation bubbles (LSB). Off surface flow visualization data, obtained by smoke injection, were used to document both the path of the vortex cores and the location of vortex core breakdown. The location of vortex core breakdown correlated well with the loss of suction pressure on the LEX and with the flow visualization results from ground facilities. Surface flow separation lines on the LEX and forebody corresponded well with the end of pressure recovery under the vortical flows. Correlation of the pressures with wind tunnel results show fair to good correlation.

  1. In-flight flow visualization characteristics of the NASA F-18 high alpha research vehicle at high angles of attack

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Delfrate, John H.; Richwine, David M.

    1991-01-01

    Surface and off-surface flow visualization techniques were used to visualize the 3-D separated flows on the NASA F-18 high alpha research vehicle at high angles of attack. Results near the alpha = 25 to 26 deg and alpha = 45 to 49 deg are presented. Both the forebody and leading edge extension (LEX) vortex cores and breakdown locations were visualized using smoke. Forebody and LEX vortex separation lines on the surface were defined using an emitted fluid technique. A laminar separation bubble was also detected on the nose cone using the emitted fluid technique and was similar to that observed in the wind tunnel test, but not as extensive. Regions of attached, separated, and vortical flow were noted on the wing and the leading edge flap using tufts and flow cones, and compared well with limited wind tunnel results.

  2. F-18 SRA closeup of nose cap showing L-Probe experiment and standard air data sensors

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This under-the-nose view of a modified F-18 Systems Research Aircraft at NASA's Dryden Flight Research Center, Edwards, California, shows three critical components of the aircraft's air data systems which are mounted on both sides of the forward fuselage. Furthest forward are two L-probes that were the focus of the recent Advanced L-probe Air Data Integration (ALADIN) experiment. Behind the L-probes are angle-of-attack vanes, while below them are the aircraft's standard pitot-static air data probes. The ALADIN experiment focused on providing pilots with angle-of-attack and angle-of-sideslip air data as well as traditional airspeed and altitude information, all from a single system. Once fully developed, the new L-probes have the potential to give pilots more accurate air data information with less hardware.

  3. In-flight flow visualization with pressure measurements at low speeds on the NASA F-18 high alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Delfrate, John H.; Fisher, David F.; Zuniga, Fanny A.

    1990-01-01

    In-flight results from surface and off-surface flow visualizations and from extensive pressure distributions document the vortical flow on the leading edge extensions (LEX) and forebody of the NASA F-18 high alpha research vehicle for low speeds and angles of attack up to 50 degs. Surface flow visualization data, obtained using the emitted fluid technique, were used to define separation lines and laminar separation bubbles. Off-surface flow visualization data, obtained by smoke injection, were used to document both the path of the vortex cores and the location of vortex core breakdown. The location of vortex core breakdown correlated well with the loss of suction pressure on the LEX and with the flow visualization results from ground facilities. Surface flow separation lines on the LEX and forebody corresponded well with the end of pressure recovery under the vortical flows. Correlation of the pressures with wind tunnel results show fair to good correlation.

  4. Method for combined FDG-PET and radiographic imaging of primary breast cancers.

    PubMed

    Adler, Lee P; Weinberg, Irving N; Bradbury, Michelle S; Levine, Edward A; Lesko, Nadine M; Geisinger, Kim R; Berg, Wendie A; Freimanis, Rita I

    2003-01-01

    The purpose of the study was to demonstrate the feasibility of a hybrid functional/anatomic breast imaging platform with biopsy capability for facilitating lesion detection and diagnosis. This platform consists of an investigative dedicated positron emission mammography (PEM) device mounted on a stereotactic X-ray mammography system, permitting sequential acquisition of mammographic and emission images during a single breast compression. There is automatic coregistration of images from both modalities, and these results can be successfully correlated with histopathologic findings. The potential utility of functional images correlated to anatomic images would include noninvasively detecting clinically and radiographically occult cancers, assessing response to therapy, discriminating between benign and malignant breast masses, and ultimately reducing the number of invasive and costly surgical interventions. A spot-digital mammogram and subsequent PEM image, collected over a 4-minute period, were obtained in a single patient with the breast in compression after intravenous injection of (F-18)-2-deoxy-2-fluoro-D-glucose (FDG) at the time of stereotactic biopsy. The authors conclude that FDG-based lesion localization information may be combined with the lesion X-ray attenuation characteristics using this common imaging platform.

  5. Evaluation of Shoulder Disorders by 2-[F-18]-fluoro-2-deoxy-D-glucose Positron Emission Tomography and Computed Tomography

    PubMed Central

    Lee, Sang Hong; Park, Sung Yong; Yu, Jae Cheol; Gorthi, Venkat

    2010-01-01

    Background Although flourine-18-flourodeoxyglucose (FDG) positron emission tomography (PET) has a limitation for localizing anatomical structures, combining it with computed tomography (CT) has made it more efficient for overcoming such limitations. This study aims to evaluate the efficacy of PET/CT for evaluating diseases of the shoulder. Methods Retrospective examination was performed on 25 patients who underwent FDG-PET/CT scanning. All the patients were over 60 years of age, and they were evaluated both clinically and radiologically for shoulder pain. The study period was from May, 2006 to May, 2008. One of the patients had metastatic lesion in a shoulder and this patient was excluded from the study, so the total number of subjects in the study was finally 24 patients. Results PET/CT showed 67% sensitivity, 73% specificity, a positive predictive value of 60%, a negative predictive value of 79%, 27% false positivity and 33% false negativity concerning shoulder pain. PET/CT showed negative finding in 4 cases that were successfully treated by operative treatment (rotator cuff tear [RCT], 3 cases; impingement syndrome, 1 case). Negative findings were also noted in 6 cases in which the pain subsided after conservative treatment (RCT, 1 case; suspected RCT, 2 cases; impingement syndrome, 3 cases). All the patients with osteoarthritis and rheumatoid arthritis had positive findings on PET/CT scanning. Conclusions PET/CT is a useful adjunct to the existing imaging modalities to assess functional and pathophysiologic processes and at a very early stage, and so PET/CT can help physicians make better preoperative and postoperative decisions on treatment. PMID:20808588

  6. Investigation of the relationship between SLA-1 and SLA-3 gene expression and susceptibility to Escherichia coli F18 in post-weaning pigs.

    PubMed

    Ye, L; Zi, C; Pan, Z Y; Zhu, J; Du, Z D; Zhu, G Q; Huang, X G; Bao, W B; Wu, S L

    2012-01-01

    Porcine post-weaning diarrhea and edema disease are principally caused by Escherichia coli strains that produce F18 adhesin. FUT1 genotyping and receptor binding studies divided piglets into E. coli F18-resistant and -sensitive groups, and the roles of SLA-1 and SLA-3 were investigated. SLA-1 and SLA-3 expression was detected in 11 pig tissues, with higher levels of SLA-1 in lung, immune tissues and gastrointestinal tract, and higher levels of SLA-3 also in lung and lymphoid tissues. Both genes were expressed higher in F18-resistant piglets, and their expression was positively correlated in different tissues; a negative correlation was observed in some tissues of F18-sensitive group, particularly in lung and lymphatic samples. Gene ontology and pathway analyses showed that SLA-1 and SLA-3 were involved in 37 biological processes, including nine pathways related to immune functions. These observations help to elucidate the relationship between SLA class I genes and E. coli F18-related porcine gastrointestinal tract diseases.

  7. (99m)Tc-DMSA (V) in Evaluation of Osteosarcoma: Comparative Studies with (18)F-FDG PET/CT in Detection of Primary and Malignant Lesions.

    PubMed

    Bandopadhyaya, G P; Gupta, Priyanka; Singh, Archana; Shukla, Jaya; Rastogi, S; Kumar, Rakesh; Malhotra, Arun

    2012-01-01

    To evaluate the role of (99m)Tc-DMSA (V) and [(18)F]FDG PET-CT in management of patients with osteosarcoma, 22 patients were included in our study. All patients underwent both (99m)Tc-DMSA (V) and whole-body [(18)F]FDG PET-CT scans within an interval of 1 week. 555-740 MBq of (99m)Tc-DMSA (V) was injected i.v. the whole-body planar, SPECT images of primary site and chest were performed after 3-4 hours. [(18)F]FDG PET-CT images were obtained 60 minutes after i.v. injection of 370 MBq of F-18 FDG. Both FDG PET-CT (mean SUV(max) = 7.1) and DMSA (V) scans showed abnormal uptake at primary site in all the 22 patients (100% sensitivity for both). Whole-body PET-CT detected metastasis in 11 pts (lung mets in 10 and lung + bone mets in 1 patient). Whole-body planar DMSA (V) and SPECT detected bone metastasis in one patient, lung mets in 7 patients and LN in 1 patient. HRCT of chest confirmed lung mets in 10 patients and inflammatory lesion in one patient. 7 patients positive for mets on DMSA (V) scan had higher uptake in lung lesions as compared to FDG uptake on PET-CT. Three patients who did not show any DMSA uptake had subcentimeter lung nodule. Resuts of both (99m)Tc-DMSA (V) (whole-body planar and SPECT imaging) and [(18)F]FDG PET-CT were comparable in evaluation of primary site lesions and metastatic lesions greater than 1 cm. Though (99m)Tc-DMSA (V) had higher uptake in the lesions as compared to [(18)F]FDG PET-CT, the only advantage [(18)F]FDG PET-CT had was that it could also detect subcentimeter lesions.

  8. Diaphragm and Laryngeal FDG Uptake With Hiccups.

    PubMed

    Srivastava, Madhur K; Jain, Avani S; Panneer, Venkat; Muthukrishnan, Indirani; Simon, Shelley

    2015-11-01

    F-FDG PET/CT study is a well-established investigation in diagnosis, treatment evaluation, and follow-up of malignant tumors. It is very important to know the normal biodistribution and physiologic uptake of F-FDG to prevent it from confusing as malignant disease. This article describes unusual but physiological uptake in the laryngeal and diaphragmatic muscles in a patient presenting as metastatic adenocarcinoma with unknown primary having hiccups. PMID:26204217

  9. FDG-PET/CT Limited to the Thorax and Upper Abdomen for Staging and Management of Lung Cancer

    PubMed Central

    Postema, Jan W. A.; Schreurs, Wendy M. J.; Lafeber, Albert; Hendrickx, Baudewijn W.; Oyen, Wim J. G.; Vogel, Wouter V.

    2016-01-01

    Purpose This study evaluates the diagnostic accuracy of [F-18]-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) of the chest/upper abdomen compared to the generally performed scan from head to upper thighs, for staging and management of (suspected) lung cancer in patients with no history of malignancy or complaints outside the thorax. Methods FDG-PET/CT scans of 1059 patients with suspected or recently proven lung cancer, with no history of malignancy or complaints outside the thorax, were analysed in a retrospective multi-centre trial. Suspect FDG-avid lesions in the chest and upper abdomen, the head and neck area above the shoulder line and in the abdomen and pelvis below the caudal tip of the liver were noted. The impact of lesions detected in the head and neck area and abdomen and pelvis on additional diagnostic procedures, staging and treatment decisions was evaluated. Results The head and neck area revealed additional suspect lesions in 7.2%, and the abdomen and pelvis in 15.8% of patients. Imaging of the head and neck area and the abdomen and pelvic area showed additional lesions in 19.5%, inducing additional diagnostic procedures in 7.8%. This resulted in discovery of additional lesions considered malignant in 10.7%, changing patient management for lung cancer in 1.2%. In (suspected) lung cancer, PET/CT limited to the chest and upper abdomen resulted in correct staging in 98.7% of patients, which led to the identical management as full field of view PET in 98.8% of patients. Conclusion High value of FDG-PET/CT for staging and correct patient management is already achieved with chest and upper abdomen. Findings in head and neck area and abdomen and pelvis generally induce investigations with limited or no impact on staging and treatment of NSCLC, and can be interpreted accordingly. PMID:27556809

  10. Posttransplant Lymphoproliferative Disorder of the Thorax: CT and FDG-PET Features in a Single Tertiary Referral Center

    PubMed Central

    Yoon, Ga Young; Kim, Mi Young; Huh, Joo Rryung; Jo, Kyung-Wook; Shim, Tae Sun

    2015-01-01

    Abstract To investigate the chest computed tomography (CT) and F-18 fluoro-2-deoxy-d-glucose positron emission tomographic (FDG-PET) findings of posttransplant lymphoproliferative disorder (PTLD) in the thorax. From November 2004 to February 2013, the cases of 12 adult patients (3 female and 9 male, age range 34–68, and median age 46 years) with proven PTLD were retrospectively reviewed. The transplanted organs included the kidney (5/12), liver (4/12), heart (1/12), combined kidney and pancreas (1/12), and hematopoietic stem cell (1/12). We investigated the relationship of the Epstein–Barr virus (EBV) to the patients’ long-term follow-up, and evaluated the characteristics of the lesions on the chest CT and FDG-PET. The lesions were classified into 2 patterns: that of lymph node and lung involvement. The interval between the transplantation and the onset of PTLD was 2 to 128 months (median, 49). Positive EBV-encoded RNA in the pathologic specimens was found in 10 patients (83.3%). Eight patients were positive for EBV PCR in their blood, and 3 patients showed seroconversion without antiviral therapy. The responses to treatment were complete in 7 cases (58.3%), partial remission in 4 cases (33.3%), and undetermined in 1 case (8.3%). The more common chest CT patterns showed lymph node involvement (10/12) rather than lung involvement (3/12). The median maximum-standardized uptake value on the FDG-PET scans was 7.7 (range, 2.7–25.5). In patients with PTLD involving the thorax, lymphadenopathy was the more common manifestation on the chest CT rather than lung involvement. The lesions showed hypermetabolism on FDG-PET. PMID:26252295

  11. Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle

    SciTech Connect

    Lopez, A.R.; Gritzo, L.A.; Hassan, B.

    1997-06-01

    For the purposes of designing improved Halon-alternative fire suppression strategies for aircraft applications, Computational Fluid Dynamics (CFD) simulations of the air flow, suppressant transport, and air-suppressant mixing within an uncluttered F18 engine nacelle were performed. The release of inert gases from a Solid Propellant Gas Generator (SPGG) was analyzed at two different injection locations in order to understand the effect of injection position on the flow patterns and the mixing of air and suppression agent. An uncluttered engine nacelle was simulated to provide insight into the global flow features as well as to promote comparisons with previous nacelle fire tests and recent water tunnel tests which included little or no clutter. Oxygen concentration levels, fuel/air residence times that would exist if a small fuel leak were present, velocity contours, and streamline patterns are presented inside the engine nacelle. The numerical results show the influence of the gent release location on regions of potential flame extinction due to oxygen inerting and high flame strain. The occurrence of inflow through the exhaust ducts on the aft end of the nacelle is also predicted. As expected, the predicted oxygen concentration levels were consistently higher than the measured levels since a fire was not modeled in this analysis. Despite differences in the conditions of these simulations and the experiments, good agreement was obtained between the CFD predictions and the experimental measurements.

  12. Extraction of Lateral-Directional Stability and Control Derivatives for the Basic F-18 Aircraft at High Angles of Attack

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Wang, Kon-Sheng Charles

    1997-01-01

    The results of parameter identification to determine the lateral-directional stability and control derivatives of an F-18 research aircraft in its basic hardware and software configuration are presented. The derivatives are estimated from dynamic flight data using a specialized identification program developed at NASA Dryden Flight Research Center. The formulation uses the linearized aircraft equations of motions in their continuous/discrete form and a maximum likelihood estimator that accounts for both state and measurement noise. State noise is used to model the uncommanded forcing function caused by unsteady aerodynamics, such as separated and vortical flows, over the aircraft. The derivatives are plotted as functions of angle of attack between 3 deg and 47 deg and compared with wind-tunnel predictions. The quality of the derivative estimates obtained by parameter identification is somewhat degraded because the maneuvers were flown with the aircraft's control augmentation system engaged, which introduced relatively high correlations between the control variables and response variables as a result of control motions from the feedback control system.

  13. 18F-FDG positron autoradiography with a particle counting silicon pixel detector.

    PubMed

    Russo, P; Lauria, A; Mettivier, G; Montesi, M C; Marotta, M; Aloj, L; Lastoria, S

    2008-11-01

    We report on tests of a room-temperature particle counting silicon pixel detector of the Medipix2 series as the detector unit of a positron autoradiography (AR) system, for samples labelled with (18)F-FDG radiopharmaceutical used in PET studies. The silicon detector (1.98 cm(2) sensitive area, 300 microm thick) has high intrinsic resolution (55 microm pitch) and works by counting all hits in a pixel above a certain energy threshold. The present work extends the detector characterization with (18)F-FDG of a previous paper. We analysed the system's linearity, dynamic range, sensitivity, background count rate, noise, and its imaging performance on biological samples. Tests have been performed in the laboratory with (18)F-FDG drops (37-37 000 Bq initial activity) and ex vivo in a rat injected with 88.8 MBq of (18)F-FDG. Particles interacting in the detector volume produced a hit in a cluster of pixels whose mean size was 4.3 pixels/event at 11 keV threshold and 2.2 pixels/event at 37 keV threshold. Results show a sensitivity for beta(+) of 0.377 cps Bq(-1), a dynamic range of at least five orders of magnitude and a lower detection limit of 0.0015 Bq mm(-2). Real-time (18)F-FDG positron AR images have been obtained in 500-1000 s exposure time of thin (10-20 microm) slices of a rat brain and compared with 20 h film autoradiography of adjacent slices. The analysis of the image contrast and signal-to-noise ratio in a rat brain slice indicated that Poisson noise-limited imaging can be approached in short (e.g. 100 s) exposures, with approximately 100 Bq slice activity, and that the silicon pixel detector produced a higher image quality than film-based AR.

  14. Synthesis of no carrier added F-18 16-fluorohexadecanoic acid (FHDA) and investigation of its labeled metabolites and its kinetics in the heart

    SciTech Connect

    DeGrado, T.R.; Bernstein, D.R.; Gatley, S.J.; Ng, C.K.; Holden, J.E.

    1984-01-01

    No carrier added FHDA was prepared via saponification of the product of silver oxide assisted reaction of near-anhydrous tetraethylammonium fluoride with methyl 16-iodohexadecanoate. The labeled fatty acid was injected into isolated perfused rat hearts. Coronary perfusate was collected for 4-9 minutes, when hearts were chilled and homogenized. F-18 in perfusate was analysed by HPLC (NH column; 50mM amm. acetate in 50% acetonitrile). Material with the same retention time as F-18 fluoroacetate (prepared by F-for-I exchange with ethyl iodoacetate) was found. Some F-18 stuck permanently to the column and was assigned as fluoride since the same fraction of label in perfusate was retained on alumina columns eluted with water. Anion exchange HPLC (SAX column; 20mM pot. phosphate, pH 7) of homogenates gave peaks corresponding to fluoroacetate plus fluoride and minor peaks which could be fluoroacetylCoA and fluorocitrate. The authors interpret their data as follows. Beta-oxidation of FHDA results in fluoroacetylCoA which either undergoes ''lethal synthesis'' to fluorocitrate or is hydrolysed to fluoroacetate which diffuses out of the heart. The source of the fluoride is not yet clear, but could complicate interpretation of FHDA kinetics measured in vivo with positron tomography. Clearance of label from FHDA in isolated perfused hearts was faster than for labeled 16-iodohexadecanoic acid, indicating that the F-18 tracer may be a more sensitive probe of myocardial fatty acid metabolism.

  15. PREPARATION OF ANHYDROUS F-18 FLUORIDE, T. Tewson. Journal of Labelled Compounds and Radiopharmaceuticals S165; 52, Supplement 1 2009

    SciTech Connect

    Tewson, T.

    2009-07-01

    The original specific aims of the grant where cut back considerably as the study section reduced both the time and the budget for the project. The objective of the grant was to show that fluorine-18 fluoride could be prepared completely anhydrous and thus substantially more reactive than conventionally dried fluoride using the method of Sun and DiMagno. This method involved using conventionally dried fluoride to prepare an aromatic fluoride in which the aromatic ring is substituted with electron withdrawing groups. The aryl fluoride is then dried and purified and the fluoride is displaced with an anhydrous nucleophile. Using fluorine-19 and macroscopic scale reactions the reactions work well and give anhydrous fluoride salts that are both more reactive and more selective in their reactions than conventionally dried fluoride. The original substrate chosen for the reaction was bromopentacyanobenzene (1). This compound proved to be easy to make but very hard to purify. As an alternative hexabromobenzene, which is commercially available in high purity, was tried. This reacted cleanly with conventionally dried F-18 fluoride in acetonitrile to give [{sup 18}F]-fluoropentabromobenzene (2), which could be dried by passage of the solution over alumina, which also removed any unreacted fluoride. The fluorine-18 fluoride could be liberated from (2) by displacement with an anhydrous nucleophilic tetra-alkylammonium salt but the anion had to be chosen with considerable care. The reaction is potentially reversible especially as, on the no carrier added scale, there is inevitably an excess of hexabromobenzene and so the displacing nucleophile is chosen to deactivate the aromatic compound to further nucleophilic displacement reactions. To this end tetrabutylammonium azide and tetrabutylammonium phenolate have been tried. Both work but the phenolate is probably the better choice. The F-18 fluoride produced by this process is substantially more reactive than conventionally dried

  16. Estimated radiation dose to the newborn in FDG-PET studies

    SciTech Connect

    Ruotsalainen, U.; Suhonen-Polvi, H.; Eronen, E.; Kinnala, A.

    1996-02-01

    The aim of this study was to estimate the radiation dose due to intravenous injection of 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (FDG) for infants studied with PET. The radioactivity concentration in the brain and bladder content was measured with PET to determine the cumulated activity in these organs in 21 infant FDG studies. The individual organ masses were estimated according to the whole-body and brain masses, and they were used to calculate the absorbed dose per unit cumulated activity (S values). For organs other than brain and bladder, the cumulated activity was defined from adult studies. For each individual patient, the absorbed dose to the brain, bladder wall and selected organs were calculated. An estimation of the effective dose was determined. Whole-body distribution of FDG in the infants differed from adults: a greater proportion of the injected activity accumulated into the brain (9% versus 7%) and less was excreted to urine (7% versus 20% respectively). The measured cumulated activity in the brain was 0.25 MBq {center_dot} h/MBq and in the bladder content 0.04 MBq {center_dot}h/MBq with a large individual variation in latter. The calculated absorbed dose was 0.24 mGy/MBq to the brain and 1.03 mGy/MBq to the bladder wall. The estimated effective dose was 0.43 mSv/MBq. The dose to the bladder wall was lower in infants as compared to adults with ordinary amounts of injected activity. The greater amount of activity remaining in the body may increase the dose to other organs. The effective dose was lower compared to adults and conventional nuclear medicine studies of infants. PET can be a valuable tool in pediatric nuclear medicine because of good resolution images, sensitive radiation measurement and a variety of tracers labeled with short-lived isotopes. 27 refs., 4 figs., 2 tabs.

  17. FDG uptake, a surrogate of tumour hypoxia?

    PubMed Central

    Van de Wiele, Christophe

    2008-01-01

    Introduction Tumour hyperglycolysis is driven by activation of hypoxia-inducible factor-1 (HIF-1) through tumour hypoxia. Accordingly, the degree of 2-fluro-2-deoxy-d-glucose (FDG) uptake by tumours might indirectly reflect the level of hypoxia, obviating the need for more specific radiopharmaceuticals for hypoxia imaging. Discussion In this paper, available data on the relationship between hypoxia and FDG uptake by tumour tissue in vitro and in vivo are reviewed. In pre-clinical in vitro studies, acute hypoxia was consistently shown to increase FDG uptake by normal and tumour cells within a couple of hours after onset with mobilisation or modification of glucose transporters optimising glucose uptake, followed by a delayed response with increased rates of transcription of GLUT mRNA. In pre-clinical imaging studies on chronic hypoxia that compared FDG uptake by tumours grown in rat or mice to uptake by FMISO, the pattern of normoxic and hypoxic regions within the human tumour xenografts, as imaged by FMISO, largely correlated with glucose metabolism although minor locoregional differences could not be excluded. In the clinical setting, data are limited and discordant. Conclusion Further evaluation of FDG uptake by various tumour types in relation to intrinsic and bioreductive markers of hypoxia and response to radiotherapy or hypoxia-dependent drugs is needed to fully assess its application as a marker of hypoxia in the clinical setting. PMID:18509637

  18. Neuroimaging in Animal Seizure Models with 18FDG-PET

    PubMed Central

    Mirrione, Martine M.; Tsirka, Stella E.

    2011-01-01

    Small animal neuroimaging has become increasingly available to researchers, expanding the breadth of questions studied with these methods. Applying these noninvasive techniques to the open questions underlying epileptogenesis is no exception. A major advantage of small animal neuroimaging is its translational appeal. Studies can be well controlled and manipulated, examining the living brain in the animal before, during, and after the disease onset or disease treatment. The results can also be compared to data collected on human patients. Over the past decade, we and others have explored metabolic patterns in animal models of epilepsy to gain insight into the circuitry underlying development of the disease. In this paper, we provide technical details on how metabolic imaging that uses 2-deoxy-2[18F]fluoro-D-glucose (18FDG) and positron emission tomography (PET) is performed and explain the strengths and limitations of these studies. We will also highlight recent advances toward understanding epileptogenesis through small animal imaging. PMID:22937232

  19. FDG-PET and Neuropsychiatric Symptoms among Cognitively Normal Elderly Persons: The Mayo Clinic Study of Aging.

    PubMed

    Krell-Roesch, Janina; Ruider, Hanna; Lowe, Val J; Stokin, Gorazd B; Pink, Anna; Roberts, Rosebud O; Mielke, Michelle M; Knopman, David S; Christianson, Teresa J; Machulda, Mary M; Jack, Clifford R; Petersen, Ronald C; Geda, Yonas E

    2016-07-14

    One of the key research agenda of the field of aging is investigation of presymptomatic Alzheimer's disease (AD). Furthermore, abnormalities in brain glucose metabolism (as measured by FDG-PET) have been reported among cognitively normal elderly persons. However, little is known about the association of FDG-PET abnormalities with neuropsychiatric symptoms (NPS) in a population-based setting. Thus, we conducted a cross-sectional study derived from the ongoing population-based Mayo Clinic Study of Aging in order to examine the association between brain glucose metabolism and NPS among cognitively normal (CN) persons aged > 70 years. Participants underwent FDG-PET and completed the Neuropsychiatric Inventory Questionnaire (NPI-Q), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI). Cognitive classification was made by an expert consensus panel. We conducted multivariable logistic regression analyses to compute odds ratios (OR) and 95% confidence intervals after adjusting for age, sex, and education. For continuous variables, we used linear regression and Spearman rank-order correlations. Of 668 CN participants (median 78.1 years, 55.4% males), 205 had an abnormal FDG-PET (i.e., standardized uptake value ratio < 1.32 in AD-related regions). Abnormal FDG-PET was associated with depression as measured by NPI-Q (OR = 2.12; 1.23-3.64); the point estimate was further elevated for APOE ɛ4 carriers (OR = 2.59; 1.00-6.69), though marginally significant. Additionally, we observed a significant association between abnormal FDG-PET and depressive and anxiety symptoms when treated as continuous measures. These findings indicate that NPS, even in community-based samples, can be an important additional tool to the biomarker-based investigation of presymptomatic AD. PMID:27447426

  20. FDG-PET and Neuropsychiatric Symptoms among Cognitively Normal Elderly Persons: The Mayo Clinic Study of Aging

    PubMed Central

    Krell-Roesch, Janina; Ruider, Hanna; Lowe, Val J.; Stokin, Gorazd B.; Pink, Anna; Roberts, Rosebud O.; Mielke, Michelle M.; Knopman, David S.; Christianson, Teresa J.; Machulda, Mary M.; Jack, Clifford R.; Petersen, Ronald C.; Geda, Yonas E.

    2016-01-01

    One of the key research agenda of the field of aging is investigation of presymptomatic Alzheimer’s disease (AD). Furthermore, abnormalities in brain glucose metabolism (as measured by FDG-PET) have been reported among cognitively normal elderly persons. However, little is known about the association of FDG-PET abnormalities with neuropsychiatric symptoms (NPS) in a population-based setting. Thus, we conducted a cross-sectional study derived from the ongoing population-based Mayo Clinic Study of Aging in order to examine the association between brain glucose metabolism and NPS among cognitively normal (CN) persons aged > 70 years. Participants underwent FDG-PET and completed the Neuropsychiatric Inventory Questionnaire (NPI-Q), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI). Cognitive classification was made by an expert consensus panel. We conducted multivariable logistic regression analyses to compute odds ratios (OR) and 95% confidence intervals after adjusting for age, sex, and education. For continuous variables, we used linear regression and Spearman rank-order correlations. Of 668 CN participants (median 78.1 years, 55.4% males), 205 had an abnormal FDG-PET (i.e., standardized uptake value ratio < 1.32 in AD-related regions). Abnormal FDG-PET was associated with depression as measured by NPI-Q (OR = 2.12; 1.23–3.64); the point estimate was further elevated for APOE ɛ4 carriers (OR = 2.59; 1.00–6.69), though marginally significant. Additionally, we observed a significant association between abnormal FDG-PET and depressive and anxiety symptoms when treated as continuous measures. These findings indicate that NPS, even in community-based samples, can be an important additional tool to the biomarker-based investigation of presymptomatic AD. PMID:27447426

  1. Estimation of radiation dose to patients from 18FDG whole body PET/CT investigations using dynamic PET scan protocol

    PubMed Central

    Kaushik, Aruna; Jaimini, Abhinav; Tripathi, Madhavi; D’Souza, Maria; Sharma, Rajnish; Mondal, Anupam; Mishra, Anil K.; Dwarakanath, Bilikere S.

    2015-01-01

    Background & objectives: There is a growing concern over the radiation exposure of patients from undergoing 18FDG PET/CT (18F-fluorodeoxyglucose positron emission tomography/computed tomography) whole body investigations. The aim of the present study was to study the kinetics of 18FDG distributions and estimate the radiation dose received by patients undergoing 18FDG whole body PET/CT investigations. Methods: Dynamic PET scans in different regions of the body were performed in 49 patients so as to measure percentage uptake of 18FDG in brain, liver, spleen, adrenals, kidneys and stomach. The residence time in these organs was calculated and radiation dose was estimated using OLINDA software. The radiation dose from the CT component was computed using the software CT-Expo and measured using computed tomography dose index (CTDI) phantom and ionization chamber. As per the clinical protocol, the patients were refrained from eating and drinking for a minimum period of 4 h prior to the study. Results: The estimated residence time in males was 0.196 h (brain), 0.09 h (liver), 0.007 h (spleen), 0.0006 h (adrenals), 0.013 h (kidneys) and 0.005 h (stomach) whereas it was 0.189 h (brain), 0.11 h (liver), 0.01 h (spleen), 0.0007 h (adrenals), 0.02 h (kidneys) and 0.004 h (stomach) in females. The effective dose was found to be 0.020 mSv/MBq in males and 0.025 mSv/MBq in females from internally administered 18FDG and 6.8 mSv in males and 7.9 mSv in females from the CT component. For an administered activity of 370 MBq of 18FDG, the effective dose from PET/CT investigations was estimated to be 14.2 mSv in males and 17.2 mSv in females. Interpretation & conclusions: The present results did not demonstrate significant difference in the kinetics of 18FDG distribution in male and female patients. The estimated PET/CT doses were found to be higher than many other conventional diagnostic radiology examinations suggesting that all efforts should be made to clinically justify and

  2. FDG PET/CT appearance of benign pilomatricoma.

    PubMed

    Bhatt, Manoj Kumar; Sommerville, Ryan; Ravi Kumar, Aravind S

    2012-07-01

    A 56-year-old patient was referred for FDG PET/CT with a right preauricular lymph node fine-needle biopsy, suggesting poorly differentiated carcinoma and no obvious primary lesion. There was intense FDG uptake in the right preauricular nodule. The node was excised, and formal histology demonstrated a benign pilomatricoma rather than malignancy. Pilomatricoma is uncommon in adults and an unusual cause for marked FDG uptake, likely due to foreign body inflammation. Pilomatricoma can be either benign or malignant. The marked FDG uptake demonstrated in our patient with benign pilomatricoma also suggests that FDG PET cannot reliably grade this rare condition.

  3. Clinical application of PET for the evaluation of brain tumors

    SciTech Connect

    Coleman, R.E.; Hoffman, J.M.; Hanson, M.W.; Sostman, H.D.; Schold, S.C. )

    1991-04-01

    The combination of FDG and PET has demonstrated clinical utility in the evaluation of patients with brain tumors. At the time of diagnosis, FDG PET provides information concerning the degree of malignancy and patient prognosis. After therapy, FDG PET is able to assess persistence of tumor, determine degree of malignancy, monitor progression, differentiate recurrence from necrosis, and assess prognosis. Other studies using PET provide information that may be clinically useful. Determination of tumor blood flow and permeability of the blood-brain barrier may help in the selection of appropriate therapy. Amino acid imaging using 11C-methionine is being evaluated in patients with brain tumors and provides different information than FDG imaging.52 references.

  4. Production of the PET bone agent (18)F-fluoride ion, simultaneously with (18)F-FDG by a single run of the medical cyclotron with minimal radiation exposure- a novel technique.

    PubMed

    Kumar, Rajeev; Sonkawade, Rajendra G; Tripathi, Madhavi; Sharma, Punit; Gupta, Priyanka; Kumar, Praveen; Pandey, Anil K; Bal, Chandrasekhar; Damle, Nishikant Avinash; Bandopadhayaya, Gurupad

    2014-01-01

    Our aim was to establish an easy and convenient procedure for the preparation of fluorine-18-sodium fluoride ((18)F-NaF) for bone positron emission tomography (PET) during routine (18)F-FDG production using the Explora FDG4 radiochemistry module (EFRM) by single run of Cyclotron with negligible radiation exposure. We compared three techniques for (18)F-NaF production during routine PET radiochemistry at our setup. In one method we used synthesis module and in other two methods we did not. In the first and third method, F-18 was directly extracted from the V-vial and in the second method, (18)F-NaF was extracted by post processing from the EFRM. In the first method, F-18 was extracted directly from V-vial manually by opening the V-vial cap. In the second method, Explora FDG-4 Module was used. First, F-18 was transferred from the V-vial. Then, after post processing in EFRM, pure F-18 was obtained in the product vial. In the third method, pure F-18 was obtained in the product vial with the help of a mechanical robotic arm. The above were followed by routine quality control of (18)F-NaF produced by each method. Results of quality control of the (18)F-NaF obtained by all three methods satisfied all parameters prescribed by the United States Pharmacopeia (USP) and the British Pharmacopeia (BP) including biological, physical and chemical specifications. The radiochemical purity was 98.5±1.5% with Rf 0.006. The level of Kryptofix-222 (K222) in (18)F-NaF was within the prescribed limit. Mean pH of (18)F-NaF was 6.0±1.5. The exposure rate around the hot cell was negligible. In conclusion, from the results it was obvious that by our method number three (18)F-NaF was directly obtained from the V-vial using mechanical robotic arms. This method was the most appropriate with minimized radiation exposure to the handling Radiochemist and was also saving time as compared to the other two methods.

  5. Advanced [18F]FDG and [11C]flumazenil PET analysis for individual outcome prediction after temporal lobe epilepsy surgery for hippocampal sclerosis

    PubMed Central

    Yankam Njiwa, J.; Gray, K.R.; Costes, N.; Mauguiere, F.; Ryvlin, P.; Hammers, A.

    2014-01-01

    Purpose We have previously shown that an imaging marker, increased periventricular [11C]flumazenil ([11C]FMZ) binding, is associated with failure to become seizure free (SF) after surgery for temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS). Here, we investigated whether increased preoperative periventricular white matter (WM) signal can be detected on clinical [18F]FDG-PET images. We then explored the potential of periventricular FDG WM increases, as well as whole-brain [11C]FMZ and [18F]FDG images analysed with random forest classifiers, for predicting surgery outcome. Methods Sixteen patients with MRI-defined HS had preoperative [18F]FDG and [11C]FMZ-PET. Fifty controls had [18F]FDG-PET (30), [11C]FMZ-PET (41), or both (21). Periventricular WM signal was analysed using Statistical Parametric Mapping (SPM8), and whole-brain image classification was performed using random forests implemented in R (http://www.r-project.org). Surgery outcome was predicted at the group and individual levels. Results At the group level, non-seizure free (NSF) versus SF patients had periventricular increases with both tracers. Against controls, NSF patients showed more prominent periventricular [11C]FMZ and [18F]FDG signal increases than SF patients. All differences were more marked for [11C]FMZ. For individuals, periventricular WM signal increases were seen at optimized thresholds in 5/8 NSF patients for both tracers. For SF patients, 1/8 showed periventricular signal increases for [11C]FMZ, and 4/8 for [18F]FDG. Hence, [18F]FDG had relatively poor sensitivity and specificity. Random forest classification accurately identified 7/8 SF and 7/8 NSF patients using [11C]FMZ images, but only 4/8 SF and 6/8 NSF patients with [18F]FDG. Conclusion This study extends the association between periventricular WM increases and NSF outcome to clinical [18F]FDG-PET, but only at the group level. Whole-brain random forest classification increases [11C]FMZ-PET's performance for predicting

  6. Differential expression of Toll-like receptor 4 signaling pathway genes in Escherichia coli F18-resistant and - sensitive Meishan piglets.

    PubMed

    Liu, Y; Gan, L N; Qin, W Y; Sun, S Y; Zhu, G Q; Wu, S L; Bao, W B

    2016-01-01

    The Toll-like receptor 4 (TLR4) signaling pathway is an important inflammatory pathways associated with the progression of numerous diseases. The aim of the present study was to investigate the relationship between TLR4 signaling and resistance to Escherichia coli F18 in locally weaned Meishan piglets. Using a real-time PCR approach, expression profiles were determined for key TLR4 signaling pathway genes TLR4, MyD88, CD14, IFN-α, IL-1β and TNF-α in the spleen, thymus, lymph nodes, duodenum and jejunum of E. coli F18-resistant and -sensitive animals. TLR4 signaling pathway genes were expressed in all the immune organs and intestinal tissues, and the expression was generally higher in the spleen and lymph nodes. TLR4 transcription was higher in the spleen of sensitive piglets (p<0.05), but there was no significant difference in TLR4 mRNA levels in other tissues. Similarly, CD14 transcription was higher in lymph nodes of sensitive animals (p<0.05) but not in other tissues. IL-1β expression was higher in the spleen and in the duodenum of resistant piglets (p<0.05, p<0.01, respectively), and there were no significant differences in other tissues. There were also no significant differences in the expression of MyD88, TNF-α and IFN-α between sensitive and resistant piglets (p>0.05). These results further confirm the involvement of the TLR4 signaling pathway in resistance to E. coli F18 in Meishan weaned piglets. The resistance appeared to be mediated via downregulation of TLR4 and CD14, and upregulation of MyD88 that may promote the release of cytokines TNF-α, IL-1β, IFN-α and other inflammatory mediators which help to fight against E. coli F18 infection. PMID:27487503

  7. Histomorphometric characteristics of immune cells in small intestine of pigs perorally immunized with vaccine candidate F18ac+ nonenterotoxigenic E. coli strain

    PubMed Central

    Kovšca Janjatović, A.; Lacković, G.; Božić, F.; Špoljarić, D.; Popović, M.; Valpotić, H.; Vijtiuk, N.; Pavičić, Ž.; Valpotić, I.

    2009-01-01

    Colidiarrhea and colienterotoxemia caused by F4+ and/or F18+ enterotoxigenic E. coli (ETEC) strains are the most prevalent infections of suckling and weaned pigs. Here we tested the immunogenicity and protective effectiveness of attenuated F18ac+ non-ETEC vaccine candidate strain against challenge infection with F4ac+ ETEC strain by quantitative phenotypic analysis of small intestinal leukocyte subsets in weaned pigs.We also evaluated levamisole as an immune response modifier (IRM) and its adjuvanticity when given in the combination with the experimental vaccine. The pigs were parenterally immunized with either levamisole (at days -2, -1 and 0) or with levamisole and perorally given F18ac+ non-ETEC strain (at day 0), and challenged with F4ac+ ETEC strain 7 days later.At day 13 the pigs were euthanatized and sampled for immunohistological/histomorphometrical analyses. Lymphoid CD3+, CD45RA+, CD45RC+, CD21+, IgA+ and myeloid SWC3+ cell subsets were identified in jejunal and ileal epithelium, lamina propria and Peyer’s patches using the avidin-biotin complex method, and their numbers were determined by computer-assisted histomorphometry. Quantitative immunophenotypic analyses showed that levamisole treated pigs had highly increased numbers of jejunal CD3+, CD45RC+ and SWC3+ cells (p<0.05) as compared to those recorded in nontreated control pigs.In the ileum of these pigs we have recorded that only CD21+ cells were significantly increased (p<0.01). The pigs that were treated with levamisole adjuvanted experimental vaccine had significantly increased numbers of all tested cell subsets in both segments of the small intestine. It was concluded that levamisole adjuvanted F18ac+ non-ETEC vaccine was a requirement for the elicitation of protective gut immunity in this model; nonspecific immunization with levamisole was less effective, but confirmed its potential as an IRM. PMID:22073355

  8. Is γ-Ray Emission from Novae Affected by Interference Effects in the F18(p,α)O15 Reaction?

    NASA Astrophysics Data System (ADS)

    Laird, A. M.; Parikh, A.; Murphy, A. St. J.; Wimmer, K.; Chen, A. A.; Deibel, C. M.; Faestermann, T.; Fox, S. P.; Fulton, B. R.; Hertenberger, R.; Irvine, D.; José, J.; Longland, R.; Mountford, D. J.; Sambrook, B.; Seiler, D.; Wirth, H.-F.

    2013-01-01

    The F18(p,α)O15 reaction rate is crucial for constraining model predictions of the γ-ray observable radioisotope F18 produced in novae. The determination of this rate is challenging due to particular features of the level scheme of the compound nucleus, Ne19, which result in interference effects potentially playing a significant role. The dominant uncertainty in this rate arises from interference between Jπ=3/2+ states near the proton threshold (Sp=6.411MeV) and a broad Jπ=3/2+ state at 665 keV above threshold. This unknown interference term results in up to a factor of 40 uncertainty in the astrophysical S-factor at nova temperatures. Here we report a new measurement of states in this energy region using the F19(He3,t)Ne19 reaction. In stark contrast to previous assumptions we find at least 3 resonances between the proton threshold and Ecm=50keV, all with different angular distributions. None of these are consistent with Jπ=3/2+ angular distributions. We find that the main uncertainty now arises from the unknown proton width of the 48 keV resonance, not from possible interference effects. Hydrodynamic nova model calculations performed indicate that this unknown width affects F18 production by at least a factor of two in the model considered.

  9. Variance of Standardized Uptake Values for FDG-PET/CT Greater in Clinical Practice than Under Ideal Study Settings

    PubMed Central

    Kumar, Virendra; Nath, Kavindra; Berman, Claudia G.; Kim, Jongphil; Tanvetyanon, Tawee; Chiappori, Alberto A; Gatenby, Robert A.; Gillies, Robert J.; Eikman, Edward A.

    2012-01-01

    Purpose Measurement variance affects the clinical effectiveness of PET-based measurement as a semi-quantitative imaging biomarker for cancer response in individual patients and for planning clinical trials. In this study, we measured test-retest reproducibility of SUV measurements under clinical practice conditions, and recorded recognized deviations from protocol compliance. Methods Instrument performance calibration, display and analyses conformed to manufacture recommendations. Baseline clinical 2-deoxy-2-[F-18]fluoro-D-glucose (FDG)-PET/CT examinations were performed and then repeated at 1 – 7 days. Intended scan initiation uptake period was to repeat the examinations at the same time for each study after injection of 12 mCi FDG tracer. Avidity of uptake was measured in 62 tumors in 21 patients as standardized uptake value for maximum voxel (SUVmax) and for a mean of sampled tumor voxels (SUVmean). Results The range of SUVmax and SUVmean was 1.07–21.47 and 0.91–14.69, respectively. Intraclass correlation coefficient (ICC) between log of SUVmax and log of SUVmean was 0.93 (95% CI: 0.88–0.95) and 0.92 (95% CI: 0.87–0.95), respectively. Correlation analysis failed to show an effect on uptake period variation on SUV measurements between the two examinations, suggesting additional sources of noise. The threshold criteria for relative difference from baseline for the 95% confidence interval were ±49% or ±44% for SUVmax or SUVmean, respectively. Conclusion Variance of SUV for FDG-PET/CT in current clinical practice in a single institution was greater than expected when compared to benchmarks reported under stringent efficacy study settings. Under comparable clinical practice conditions, interpretation of changes in tumor avidity in individuals, and assumptions in planning clinical trials may be affected. PMID:23354032

  10. Prognostic value of interim 18F-FDG PET/CT in diffuse large B-cell lymphoma

    PubMed Central

    Ying, Zhitao; Wang, Xuejuan; Song, Yuqin; Zheng, Wen; Wang, Xiaopei; Xie, Yan; Lin, Ningjing; Tu, Meifeng; Ping, Lingyan; Liu, Weiping; Deng, Lijuan; Zhang, Chen; Yang, Zhi

    2013-01-01

    Objective Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease. The prognostic factor currently used is not accurate enough to predict the outcomes of patients with DLBCL. The prognostic significance of interim PET/CT in DLBCL remains controversial. The aim of this study is to determine the predictive value of interim 18F-FDG PET/CT after first-line treatment in patients with DLBCL. Methods Thirty-two patients with DLBCL underwent baseline, interim and post-treatment 18F-FDG PET/CT scans. Imaging results were analyzed for the survival of patients via software SPSS 13.0, retrospectively. Results Thirty-one of the 32 patients were treated with R-CHOP regimen, and interim 18F-FDG PET/CT of 24 patients was performed after 2 cycles of treatment. After a median follow-up period of 16.7 months, the 2-year progression-free survival (PFS) rates were significantly different between the groups above and below SUVmax cut-off value of 2.5 (P=0.039). No significant differences were found in the 2-year PFS rates if SUVmax cut-off values were set as 2.0 and 3.0, respectively (P=0.360; P=0.113). Conclusions Interim PET/CT could predict the prognosis of DLBCL patients with the SUVmax cut-off value of 2.5, but more clinical data should be concluded to confirm this conclusion. Key Words Fludeoxyglucose F18; lymphoma; large cell; diffuse; prognosis; standard utility value PMID:23372347

  11. [F-18]-Fluoromisonidazole Quantification of Hypoxia in Human Cancer Patients using Image-derived Blood Surrogate Tissue Reference Regions

    PubMed Central

    Muzi, Mark; Peterson, Lanell M.; O’Sullivan, Janet N.; Fink, James R.; Rajendran, Joseph G.; McLaughlin, Lena J.; Muzi, John P.; Mankoff, David A.; Krohn, Kenneth A.

    2015-01-01

    18F-FMISO is the most widely used PET agent for imaging hypoxia, a condition associated with resistance to tumor therapy. 18F-FMISO equilibrates in normoxic tissues, but is retained under hypoxic conditions because of reduction and binding to macromolecules. A simple tissue-to-blood ratio (TB) is suitable for quantifying hypoxia. A threshold of TB ≥ 1.2 is useful in discriminating the hypoxic volume (HV) of tissue; TBmax is the maximum intensity of the hypoxic region and does not invoke a threshold. Because elimination of blood sampling would simplify clinical use, we tested the validity of using imaging regions as a surrogate for blood sampling. Methods Patients underwent 20 min 18F-FMISO scans during the 90–140 min interval post-injection with venous blood sampling. 223 18F-FMISO patient studies had detectable surrogate blood regions in the field-of-view. Quantitative parameters of hypoxia (TBmax, HV) derived from blood samples were compared to values using surrogate blood regions derived from heart, aorta and/or cerebellum. In a subset of brain cancer patients, parameters from blood samples and from cerebellum were compared for their ability to independently predict outcome. Results Vascular regions of heart showed the highest correlation to measured blood activity (R2 = 0.84). For brain studies, cerebellar activity was similarly correlated to blood samples. In brain cancer patients, Kaplan-Meier analysis showed that image-derived reference regions had nearly identical predictive power as parameters derived from blood, thus obviating the need for venous sampling in these patients. Conclusions Simple static analysis of 18F-FMISO PET captures both the intensity (TBmax) and spatial extent (HV) of tumor hypoxia. An image-derived region to assess blood activity can be used as a surrogate for blood sampling in quantification of hypoxia. PMID:26112020

  12. NI-37INCREASED CEREBRAL AMINO ACID UPTAKE DURING AND AFTER EPILEPTIC DISORDERS MIMICS BRAIN TUMOR IN 18F-FET PET

    PubMed Central

    Hutterer, Markus; Krenn, Yvonne; Kunz, Alexander; McCoy, Marc; Egger, Barbara; Schröder, Michael; Wendl, Christina; Marienhagen, Jörg; Fritsch, Brita; Urbach, Horst; Meyer, Philipp T.; Galldiks, Norbert; Langen, Karl-Josef; Hau, Peter; Trinka, Eugen

    2014-01-01

    BACKGROUND: O-(2-[F-18]fluoroethyl)-L-tyrosine (18F-FET) PET has become an important diagnostic tool in addition to standard MRI to delineate cerebral gliomas. However, 18F-FET uptake has also been observed in non-tumoral lesions. METHODS AND RESULTS: We report on abnormal non-tumoral 18F-FET uptake in 6 patients with epileptic disorders: Patients A-C with clinically stable anaplastic astrocytoma over years, Patient D with anaplastic oligodendroglioma with stable residual tumor, Patient E with initial diagnosis of glioblastoma, Patient F with subacute cerebral ischemia. All patients presented initially with repeated epileptic seizures or status epilepticus and typical clinical and EEG findings. Standard MRI (T1 + /-contrast, T2/FLAIR) showed cortical and subcortical contrast enhancement and/or T2/FLAIR signal alterations and 18F-FET PET demonstrated a significantly increased cortical amino acid uptake. 18F-FET uptake and contrast enhancement on MRI resolved completely after cessation of epileptic activity. Patient C suffered from a prolonged postictal state. In that patient, EEG monitoring demonstrated a left hemispheric deceleration without signs of epileptic discharges; additionally, 18F-FDG PET and HMPAO SPECT showed cortical glucose hypometabolism and hypoperfusion, not consistent with a status epilepticus. After 14 weeks, clinical symptoms and the cortical 18F-FET uptake resolved completely. CONCLUSION: Abnormal 18F-FET uptake may occur in patients with epileptic disorders in brain areas not infiltrated by tumor. The reason for this phenomenon is yet unknown.

  13. Appropriateness criteria of FDG PET/CT in oncology

    PubMed Central

    Agrawal, Archi; Rangarajan, Venkatesh

    2015-01-01

    18Fluorine-2-fluoro-2-Deoxy-d-glucose (18F-FDG) positron emission tomography/computerized tomography (PET/CT) is a well-established functional imaging method widely used in oncology. In this article, we have incorporated the various indications for 18FDG PET/CT in oncology based on available evidence and current guidelines. Growing body of evidence for use of 18FDG PET/CT in select tumors is also discussed. This article attempts to give the reader an overview of the appropriateness of using 18F-FDG PET/CT in various malignancies. PMID:25969632

  14. Allergic Reaction to Ginkgo Nut on FDG PET/CT.

    PubMed

    Han, Eun Ji; Park, Hye Lim; Kim, Sung Hoon

    2016-09-01

    We report the case of a 36-year-old woman who previously underwent total thyroidectomy for papillary thyroid carcinoma. F FDG PET/CT images demonstrated multiple lymph nodes with increased FDG uptake in the neck, chest, and abdomen and diffusely increased FDG uptake in the spleen, which were highly suspicious findings for malignant lymphoma. However, subsequent biopsy of axillary lymph node presented reactive hyperplasia. Detailed history revealed that the patient had a history of generalized edema and severe arthralgia after contact with ginkgo nut one week ago. This case highlights allergic reaction mimicking lymphoma on FDG PET/CT. PMID:27276210

  15. Pulmonary intravascular lymphoma detected by FDG PET-CT: a case report.

    PubMed

    Kohan, A A; Paganini, L; Biedak, P; Arma, J I; Dalurzo, M C L; Garcia-Monaco, R D

    2013-01-01

    Intravascular lymphoma is a rare subtype of extranodal Non-Hodgkin's lymphoma. Its prognosis is poor in a high percentage of cases due to its insidious appearance and low clinical suspicion. Its diagnosis is usually only reached after an autopsy. It may affect different organs as a whole or only one organ. It is extremely rare that the lung is the only damaged organ. Its diagnosis depends of the clinician's suspicion and proper evaluation with imaging studies as well as correct selection of the organ to be biopsied. When detected on time, the treatment of choice is a combination of a series of chemotherapy associated to a monoclonal antibody (anti-CD20). We present the case of a male patient who underwent a positron emission tomography-computed tomography with 2-[F-18]-fluoro-2 deoxy-D-glucose (FDG) due to symptoms suggestive of a lymphoproliferative disease with no clear structural abnormalities. The images led to a diagnosis of pulmonary intravascular large B cell lymphoma.

  16. Global emission estimates and radiative impact of C4F10, C5F12, C6F14, C7F16 and C8F18

    NASA Astrophysics Data System (ADS)

    Ivy, D. J.; Rigby, M.; Baasandorj, M.; Burkholder, J. B.; Prinn, R. G.

    2012-05-01

    Global emission estimates based on new atmospheric observations are presented for the acylic high molecular weight perfluorocarbons (PFCs): decafluorobutane (C4F10), dodecafluoropentane (C5F12), tetradecafluorohexane (C6F14), hexadecafluoroheptane (C7F16) and octadecafluorooctane (C8F18). Emissions are estimated using a 3-dimensional chemical transport model and an inverse method that includes a growth constraint on emissions. The observations used in the inversion are based on newly measured archived air samples that cover a 39-yr period, from 1973 to 2011, and include 36 Northern Hemispheric and 46 Southern Hemispheric samples (Ivy et al., 2012). The derived emission estimates show that global emission rates were largest in the 1980s and 1990s for C4F10 and C5F12, and in the 1990s for C6F14,C7F16 and C8F18. After a subsequent decline, emissions have remained relatively stable, within 20%, for the last 5 yr. Bottom-up emission estimates are available from the Emission Database for Global Atmospheric Research version 4.2 (EDGARv4.2) for C4F10, C5F12, C6F14 and C7F16, and inventories of C4F10, C5F12 andC6F14 are reported to the United Nations' Framework Convention on Climate Change (UNFCCC) by Annex 1 countries that have ratified the Kyoto Protocol. The atmospheric measurement based emission estimates are 20 times larger than EDGARv4.2 for C4F10 and over three orders of magnitude for C5F12. The derived emission estimates for C6F14 largely agree with the bottom-up estimates from EDGARv4.2. Moreover, the C7F16 emission estimates are comparable to those of EDGARv4.2 at their peak in the 1990s, albeit significant underestimation for the other time periods. There are no bottom-up emission estimates for C8F18, thus the emission rates reported here are the first for C8F18. The reported inventories for C4F10, C5F12 and C6F14 to UNFCCC are five to ten times lower than those estimated in this study. In addition, we present measured infrared absorption spectra for C7F16 and C8

  17. Global emission estimates and radiative impact of C4F10, C5F12, C6F14, C7F16 and C8F18

    NASA Astrophysics Data System (ADS)

    Ivy, D. J.; Rigby, M.; Baasandorj, M.; Burkholder, J. B.; Prinn, R. G.

    2012-08-01

    Global emission estimates based on new atmospheric observations are presented for the acylic high molecular weight perfluorocarbons (PFCs): decafluorobutane (C4F10), dodecafluoropentane (C5F12), tetradecafluorohexane (C6F14), hexadecafluoroheptane (C7F16) and octadecafluorooctane (C8F18). Emissions are estimated using a 3-dimensional chemical transport model and an inverse method that includes a growth constraint on emissions. The observations used in the inversion are based on newly measured archived air samples that cover a 39-yr period, from 1973 to 2011, and include 36 Northern Hemispheric and 46 Southern Hemispheric samples. The derived emission estimates show that global emission rates were largest in the 1980s and 1990s for C4F10 and C5F12, and in the 1990s for C6F14, C7F16 and C8F18. After a subsequent decline, emissions have remained relatively stable, within 20%, for the last 5 yr. Bottom-up emission estimates are available from the Emission Database for Global Atmospheric Research version 4.2 (EDGARv4.2) for C4F10, C5F12, C6F14 and C7F16, and inventories of C4F10, C5F12 and C6F14 are reported to the United Nations' Framework Convention on Climate Change (UNFCCC) by Annex 1 countries that have ratified the Kyoto Protocol. The atmospheric measurement-based emission estimates are 20 times larger than EDGARv4.2 for C4F10 and over three orders of magnitude larger for C5F12 (with 2008 EDGARv4.2 estimates for C5F12 at 9.6 kg yr-1, as compared to 67±53 t yr-1 as derived in this study). The derived emission estimates for C6F14 largely agree with the bottom-up estimates from EDGARv4.2. Moreover, the C7F16 emission estimates are comparable to those of EDGARv4.2 at their peak in the 1990s, albeit significant underestimation for the other time periods. There are no bottom-up emission estimates for C8F18, thus the emission rates reported here are the first for C8F18. The reported inventories for C4F10, C5F12 and C6F14 to UNFCCC are five to ten times lower than those

  18. Brain PET metabolic abnormalities in a case of varicella-zoster virus encephalitis.

    PubMed

    Coiffard, Benjamin; Guedj, Eric; Daumas, Aurélie; Leveque, Pierre; Villani, Patrick

    2014-09-01

    The role of brain 18F-FDG PET in the diagnostic evaluation of encephalitis has been recently suggested, especially in limbic encephalitis, but descriptions are mainly limited to small case reports. However, the evaluation of cerebral metabolism by 18F-FDG PET has never been described for varicella-zoster virus encephalitis. We report the first case of varicella-zoster virus encephalitis in which 18F-FDG PET revealed brain metabolic abnormalities. Brain metabolic PET imaging was analyzed by comparing the patient's brain 18F-FDG PET scans to that of 12 healthy subjects. Compared with healthy subjects, significant hypometabolism and hypermetabolism were found and evolved over time with treatment.

  19. Enhancement of 18F-Fluorodeoxyglucose Metabolism in Rat Brain Frontal Cortex Using a β3 Adrenoceptor Agonist

    PubMed Central

    Mirbolooki, M. Reza; Schade, Kimberly N.; Constantinescu, Cristian C.; Pan, Min-Liang; Mukherjee, Jogeshwar

    2014-01-01

    We report the use of β3-adrenergic receptor mediated activation of rat brain frontal cortex using mirabegron (a selective β3-adrenoceptor agonist), measured by 18F-FDG PET/CT. Another β3-agonis t, CL 316,243, did not have this effect due to impermeability through the blood brain barrier (BBB), while atomoxetine, a norepinephrine transporter blocker, did increase 18F-FDG uptake in the frontal cortex. Mirabegron exhibited a dose-dependent increase in frontal cortex 18F-FDG uptake. These findings suggest a possible use of selective β3-adrenoceptor agonists in reversing regional glucose hypometabolism in the brain. PMID:25347981

  20. 99m-Tc-ubiquicidin scintigraphy in diagnosis of knee prosthesis infection and comparison with F-18 fluorodeoxy-glucose positron emission tomography/computed tomography.

    PubMed

    Kamaleshwaran, Koramadai Karuppusamy; Rajkumar, N; Mohanan, Vyshak; Kalarikal, Radhakrishnan; Shinto, Ajit Sugunan

    2015-01-01

    Total knee arthroplasty has witnessed a significant increase in recent years. Despite the advantages of this surgical procedure, it has some complications, the most serious of which is prosthetic infection. The discrimination of bacterial infections from sterile inflammatory processes is of great importance in the management of periprosthetic infection (PPI). Ubiquicidin (UBI) is a synthetic antimicrobial peptide fragment reported to be highly infection-specific. Tc99m-UBI has recently been reported to be a promising radiotracer for infection imaging. We report a case of left knee PPI diagnosed using 99mTc-UBI scintigraphy and compared with F-18 fluorodeoxy-glucose positron emission tomography.

  1. 99m-Tc-ubiquicidin scintigraphy in diagnosis of knee prosthesis infection and comparison with F-18 fluorodeoxy-glucose positron emission tomography/computed tomography

    PubMed Central

    Kamaleshwaran, Koramadai Karuppusamy; Rajkumar, N; Mohanan, Vyshak; Kalarikal, Radhakrishnan; Shinto, Ajit Sugunan

    2015-01-01

    Total knee arthroplasty has witnessed a significant increase in recent years. Despite the advantages of this surgical procedure, it has some complications, the most serious of which is prosthetic infection. The discrimination of bacterial infections from sterile inflammatory processes is of great importance in the management of periprosthetic infection (PPI). Ubiquicidin (UBI) is a synthetic antimicrobial peptide fragment reported to be highly infection-specific. Tc99m-UBI has recently been reported to be a promising radiotracer for infection imaging. We report a case of left knee PPI diagnosed using 99mTc-UBI scintigraphy and compared with F-18 fluorodeoxy-glucose positron emission tomography. PMID:26170572

  2. Aeropropulsive characteristics of Mach numbers up to 2.2 of axisymmetric and nonaxisymmetric nozzles installed on an F-18 model

    NASA Technical Reports Server (NTRS)

    Capone, F. J.

    1982-01-01

    An investigation to determine the aeropropulsive characteristics of nonaxisymmetric nozzles on an F-18 jet effects model was conducted in the Langley 16-foot transonic tunnel and the AEDC 16-foot supersonic wind tunnel. The performance of a two dimensional convergent-divergent nozzle, a single expansion ramp nozzle, and a wedge nozzle was compared with that of the baseline axisymmetric nozzle. Test data were obtained at static conditions and at Mach numbers from 0.60 to 2.20 at an angle of attack of 0 deg. Nozzle pressure ratio was varied from jet-off to about 20.

  3. F-18 High Alpha Research Vehicle (HARV) parameter identification flight test maneuvers for optimal input design validation and lateral control effectiveness

    NASA Technical Reports Server (NTRS)

    Morelli, Eugene A.

    1995-01-01

    Flight test maneuvers are specified for the F-18 High Alpha Research Vehicle (HARV). The maneuvers were designed for open loop parameter identification purposes, specifically for optimal input design validation at 5 degrees angle of attack, identification of individual strake effectiveness at 40 and 50 degrees angle of attack, and study of lateral dynamics and lateral control effectiveness at 40 and 50 degrees angle of attack. Each maneuver is to be realized by applying square wave inputs to specific control effectors using the On-Board Excitation System (OBES). Maneuver descriptions and complete specifications of the time/amplitude points define each input are included, along with plots of the input time histories.

  4. Disseminated Skeletal Muscle and Cardiac Metastasis from Squamous Cell Carcinoma of the Lung Detected with FDG and FLT PET/CT

    PubMed Central

    Jain, Tarun Kumar; Rayamajhi, Sampanna Jung; Basher, Rajender Kumar; Gupta, Dheeraj; Maturu, Venkata Nagarjuna; Mittal, Bhagwant Rai

    2016-01-01

    Lung cancer is one of the leading cancers all over the world. Positron emission tomography (PET) using 18F fluorodeoxyglucose (18F FDG) is useful for staging of the disease and decide the appropriate management. 3’-deoxy-3’-18 F-fluorothymidine (18F FLT) is a tracer being extensively evaluated currently and is said to represent tumor proliferation. Common sites of metastases from lung cancer include adrenal glands, bone, and brain. Muscle metastasis and cardiac metastasis are uncommon findings. We report a case of squamous cell carcinoma of the lung with metastases to multiple skeletal muscles and myocardium detected with both FDG and FLT PET/computed tomography (CT).

  5. Disseminated Skeletal Muscle and Cardiac Metastasis from Squamous Cell Carcinoma of the Lung Detected with FDG and FLT PET/CT.

    PubMed

    Jain, Tarun Kumar; Rayamajhi, Sampanna Jung; Basher, Rajender Kumar; Gupta, Dheeraj; Maturu, Venkata Nagarjuna; Mittal, Bhagwant Rai

    2016-09-01

    Lung cancer is one of the leading cancers all over the world. Positron emission tomography (PET) using 18F fluorodeoxyglucose (18F FDG) is useful for staging of the disease and decide the appropriate management. 3'-deoxy-3'-18 F-fluorothymidine (18F FLT) is a tracer being extensively evaluated currently and is said to represent tumor proliferation. Common sites of metastases from lung cancer include adrenal glands, bone, and brain. Muscle metastasis and cardiac metastasis are uncommon findings. We report a case of squamous cell carcinoma of the lung with metastases to multiple skeletal muscles and myocardium detected with both FDG and FLT PET/computed tomography (CT). PMID:27651747

  6. Medial thalamic 18-FDG uptake following inescapable shock correlates with subsequent learned helpless behavior

    SciTech Connect

    Mirrione,M.M.; Mirrione, M.M.; Schulz, D.; Dewey, S.L.; Henn, F.A.

    2009-12-06

    The learned helplessness paradigm has been repeatedly shown to correlate with neurobiological aspects of depression in humans. In this model, rodents are exposed inescapable foot-shock in order to reveal susceptibility to escape deficit, defined as 'learned helplessness' (LH). Few methods are available to probe the neurobiological aspects underlying the differences in susceptibility in the living animal, thus far being limited to studies examining regional neurochemical changes with microdialysis. With the widespread implementation of small animal neuroimaging methods, including positron emission tomography (PET), it is now possible to explore the living brain on a systems level to define regional changes that may correlate with vulnerability to stress. In this study, 12 wild type Sprague-Dawley rats were exposed to 40 minutes of inescapable foot-shock followed by metabolic imaging using 2-deoxy-2[{sup 18}F]fluoro-D-glucose (18-FDG) 1 hour later. The escape test was performed on these rats 48 hours later (to accommodate radiotracer decay), where they were given the opportunity to press a lever to shut off the shock. A region of interest (ROI) analysis was used to investigate potential correlations (Pearson Regression Coefficients) between regional 18-FDG uptake following inescapable shock and subsequent learned helpless behavior (time to finish the test; number of successful lever presses within 20 seconds of shock onset). ROI analysis revealed a significant positive correlation between time to finish and 18-FDG uptake, and a negative correlation between lever presses and uptake, in the medial thalamic area (p=0.033, p=0.036). This ROI included the paraventricular thalamus, mediodorsal thalamus, and the habenula. In an effort to account for possible spillover artifact, the posterior thalamic area (including ventral medial and lateral portions) was also evaluated but did not reveal significant correlations (p=0.870, p=0.897). No other significant correlations were

  7. [F-18]Fluorodihydrorotenone: Synthesis and evaluation of a mitochondrial electron transport chain (ETC) complex I probe for PET

    SciTech Connect

    VanBrocklin, H.F.; Enas, J.D.; Hanrahan, S.M.

    1994-05-01

    The mitochondrial electron transport chain (ETC) consists of five enzyme complexes (I-V) which participate in the transfer of electrons to oxygen and phosphorylation of ADP (oxidative phosphorylation). ETC dysfunction has been linked to several genetic neurological diseases as well as implicated in Parkinson`s (complex I) and Huntington`s (complex I) disease and normal aging processes. Dihydrorotenone (DHR) is a specific high affinity inhibitor of complex I. In order to develop a PET tracer for complex I, we have labeled DHR with fluorine-18. The tosylate precursor was produced in three steps from commercially available rotenone. Fluorine-18 was introduced by nucleophilic displacement of the tosylate using tetrabutyl-ammonium fluoride. Subsequent oxidation with MnO{sub 2} and HPLC purification gave the desired [{sup 18}F]fluoro-DHR. Initial biodistribution studies were carried out in {approximately}200 g male Sprague-Dawley rats. The tracer was taken up rapidly in the heart, an organ highly enriched with mitochondria, (5.5-6% injected dose (ID)/g at 30 minutes) and in the brain ({approximately}1.5% ID/g at 1 hour).

  8. The mediational effects of FDG hypometabolism on the association between cerebrospinal fluid biomarkers and neurocognitive function.

    PubMed

    Dowling, N Maritza; Johnson, Sterling C; Gleason, Carey E; Jagust, William J

    2015-01-15

    Positive cerebrospinal fluid (CSF) biomarkers of tau and amyloid beta42 suggest possible active underlying Alzheimer's disease (AD) including neurometabolic dysfunction and neurodegeneration leading to eventual cognitive decline. But the temporal relationship between CSF, imaging markers of neural function, and cognition has not been described. Using a statistical mediation model, we examined relationships between cerebrospinal fluid (CSF) analytes (hyperphosphorylated tau (p-Tau(181p)), β-amyloid peptides 1-42 (Aβ(1-42)), total tau (t-Tau), and their ratios); change in cognitive function; and change in [18F]fluorodeoxyglucose (FDG) uptake using positron emission tomography (PET). We hypothesized that a) abnormal CSF protein values at baseline, result in cognitive declines by decreasing neuronal glucose metabolism across time, and b) the role of altered glucose metabolism in the assumed causal chain varies by brain region and the nature of CSF protein alteration. Data from 412 individuals participating in Alzheimer's Disease Neuroimaging (ADNI) cohort studies were included in analyses. At baseline, individuals were cognitively normal (N = 82), or impaired: 241 with mild cognitive impairment, and 89 with Alzheimer's disease. A parallel-process latent growth curve model was used to test mediational effects of changes in regional FDG-PET uptake over time in relation to baseline CSF biomarkers and changes in cognition, measured with the 13-item Alzheimer Disease's Assessment Scale-cognitive subscale (ADAS-Cog). Findings suggested a causal sequence of events; specifically, FDG hypometabolism acted as a mediator between antecedent CSF biomarker alterations and subsequent cognitive impairment. Higher baseline concentrations of t-Tau, and p-Tau(181p) were more predictive of decline in cerebral glucose metabolism than lower baseline concentrations of Aβ(1-42). FDG-PET changes appeared to mediate t-Tau or t-Tau/Aβ(1-42)-associated cognitive change across all brain

  9. The Mediational Effects of FDG Hypometabolism on the Association between Cerebrospinal Fluid Biomarkers and Neurocognitive Function

    PubMed Central

    Dowling, N. Maritza; Johnson, Sterling C.; Gleason, Carey E.; Jagust, William J.

    2014-01-01

    Positive cerebrospinal fluid (CSF) biomarkers of tau and amyloid beta42 suggest possible active underlying Alzheimer’s Disease (AD) including neurometabolic dysfunction and neurodegeneration leading to eventual cognitive decline. But the temporal relationship between CSF, imaging markers of neural function, and cognition has not been described. Using a statistical mediation model, we examined relationships between cerebrospinal fluid (CSF) analytes (hyperphosphorylated tau (p-Tau181p), β-amyloid 1–42 (Aβ1–42), total tau (t-Tau), and their ratios); change in cognitive function; and change in [18F]fluorodeoxyglucose (FDG) uptake using positron emission tomography (PET). We hypothesized that a) abnormal CSF protein values at baseline, result in cognitive declines by decreasing neuronal glucose metabolism across time, and b) the role of altered glucose metabolism in the assumed causal chain varies by brain region and the nature of CSF protein alteration. Data from 412 individuals participating in Alzheimer’s Disease Neuroimaging (ADNI) cohort studies were included in analyses. At baseline, individuals were cognitively normal (N = 82), or impaired: 241 with mild cognitive impairment, and 89 with Alzheimer’s disease. A parallel-process latent growth curve model was used to test mediational effects of changes in regional FDG-PET uptake over time in relation to baseline CSF biomarkers and changes in cognition, measured with the 13-item Alzheimer Disease’s Assessment Scale–cognitive subscale (ADAS-Cog). Findings suggested a causal sequence of events; specifically, FDG hypometabolism acted as a mediator between antecedent CSF biomarker alterations and subsequent cognitive impairment. Higher baseline concentrations of t-Tau, and p-Tau181p were more predictive of decline in cerebral glucose metabolism than lower baseline concentrations of Aβ1–42. FDG-PET changes appeared to mediate t-Tau or t-Tau/Aβ1–42 -associated cognitive change across all brain

  10. Multiaxis Thrust-Vectoring Characteristics of a Model Representative of the F-18 High-Alpha Research Vehicle at Angles of Attack From 0 deg to 70 deg

    NASA Technical Reports Server (NTRS)

    Asbury, Scott C.; Capone, Francis J.

    1995-01-01

    An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the multiaxis thrust-vectoring characteristics of the F-18 High-Alpha Research Vehicle (HARV). A wingtip supported, partially metric, 0.10-scale jet-effects model of an F-18 prototype aircraft was modified with hardware to simulate the thrust-vectoring control system of the HARV. Testing was conducted at free-stream Mach numbers ranging from 0.30 to 0.70, at angles of attack from O' to 70', and at nozzle pressure ratios from 1.0 to approximately 5.0. Results indicate that the thrust-vectoring control system of the HARV can successfully generate multiaxis thrust-vectoring forces and moments. During vectoring, resultant thrust vector angles were always less than the corresponding geometric vane deflection angle and were accompanied by large thrust losses. Significant external flow effects that were dependent on Mach number and angle of attack were noted during vectoring operation. Comparisons of the aerodynamic and propulsive control capabilities of the HARV configuration indicate that substantial gains in controllability are provided by the multiaxis thrust-vectoring control system.

  11. F-18 high alpha research vehicle surface pressures: Initial in-flight results and correlation with flow visualization and wind-tunnel data

    NASA Technical Reports Server (NTRS)

    Fisher, David F.; Banks, Daniel W.; Richwine, David M.

    1990-01-01

    Pressure distributions measured on the forebody and the leading-edge extensions (LEX's) of the NASA F-18 high alpha research vehicle (HARV) were reported at 10 and 50 degree angles of attack and at Mach 0.20 to 0.60. The results were correlated with HARV flow visualization and 6-percent scale F-18 wind-tunnel-model test results. The general trend in the data from the forebody was for the maximum suction pressure peaks to first appear at an angle of attack (alpha) of approximately 19 degrees and increase in magnitude with angle of attack. The LEX pressure distribution general trend was the inward progression and increase in magnitude of the maximum suction peaks up to vortex core breakdown and then the decrease and general flattening of the pressure distribution beyond that. No significant effect of Mach number was noted for the forebody results. However, a substantial compressibility effect on the LEX's resulted in a significant reduction in vortex-induced suction pressure as Mach number increased. The forebody primary and the LEX secondary vortex separation lines, from surface flow visualization, correlated well with the end of pressure recovery, leeward and windward, respectively, of maximum suction pressure peaks. The flight to wind-tunnel correlations were generally good with some exceptions.

  12. FDG-PET Assessment of the Effect of Head and Neck Radiotherapy on Parotid Gland Glucose Metabolism

    SciTech Connect

    Roach, Michael C.; Turkington, Timothy G.; Higgins, Kristin A.; Hawk, Thomas C.; Hoang, Jenny K.; Brizel, David M.

    2012-01-01

    Purpose: Functional imaging with [F-18]-fluorodeoxyglucose positron emission tomography (FDG-PET) provides the opportunity to define the physiology of the major salivary glands before and after radiation therapy. The goal of this retrospective study was to identify the radiation dose-response relationship of parotid gland glucose metabolism in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods: Forty-nine adults with HNSCC were identified who had curative intent intensity-modulated radiation therapy (IMRT) and FDG-PET imaging before and after treatment. Using a graphical user interface, contours were delineated for the parotid glands on axial CT slices while all authors were blinded to paired PET slices. Average and maximal standard uptake values (SUV) were measured within these anatomic regions. Changes in SUV and volume after radiation therapy were correlated with parotid gland dose-volume histograms from IMRT plans. Results: The average parotid gland volume was 30.7 mL and contracted 3.9 {+-} 1.9% with every increase of 10 Gy in mean dose (p = 0.04). However, within the first 3 months after treatment, there was a uniform reduction of 16.5% {+-} 7.3% regardless of dose. The average SUV{sub mean} of the glands was 1.63 {+-} 0.48 pretreatment and declined by 5.2% {+-} 2.5% for every increase of 10 Gy in mean dose (p = 0.04). The average SUV{sub max} was 4.07 {+-} 2.85 pretreatment and decreased in a sigmoid manner with mean dose. A threshold of 32 Gy for mean dose existed, after which SUV{sub max} declined rapidly. Conclusion: Radiation dose responses of the parotid glands can be measured by integrated CT/FDG-PET scans. Retrospective analysis showed sigmoidal declines in the maximum metabolism but linear declines in the average metabolism of the glands with dose. Future studies should correlate this decline in FDG uptake with saliva production to improve treatment planning.

  13. Brain PET in the Diagnosis of Alzheimer’s Disease

    PubMed Central

    Marcus, Charles; Mena, Esther; Subramaniam, Rathan M.

    2015-01-01

    Objectives The aim of this article was to review the current role of brain PET in the diagnosis of Alzheimer dementia. The characteristic patterns of glucose metabolism on brain FDG-PET can help in differentiating Alzheimer’s disease from other causes of dementia such as frontotemporal dementia and dementia of Lewy body. Amyloid brain PET may exclude significant amyloid deposition and thus Alzheimer’s disease in appropriate clinical setting. Conclusions FDG-PET and amyloid PET imaging are valuable in the assessment of patients with Alzheimer’s disease. PMID:25199063

  14. Effects of the -791(C→T) mutation in the promoter for tumor necrosis factor alpha on gene expression and resistance of Large White pigs to enterotoxigenic Escherichia coli F18.

    PubMed

    Liu, Ying; Dai, Chaohui; Sun, Li; Zhu, Guoqiang; Wu, Shenglong; Bao, Wenbin

    2016-07-01

    Tumor necrosis factor alpha (TNF-α) plays an important role in the immune system. In this study, TNF-α expression was analyzed in 11 tissues of 8 piglets resistant to enterotoxigenic Escherichia coli (ETEC) F18 and 8 ETEC F18-susceptible piglets from the Large White breed. The expression levels of TNF-α were high in immune organs (spleen, lung, thymus, and lymph nodes). The levels were higher in ETEC F18-resistant piglets than in ETEC F18-susceptible piglets, with significant differences in spleen, kidney, thymus, lymph node, and duodenum (P < 0.05). The mutation TNF-α -791(C→T) and 3 genotypes (CC, CT, and TT) were identified. The TNF-α expression levels in the spleen, kidney, lymph nodes, and duodenum were significantly higher in the TT pigs than in the CC pigs (P < 0.05). Thus, TNF-α -791(C→T) has significant effects on mRNA expression and may regulate ETEC F18 resistance of weaning piglets. Therefore, the -791(C→T) mutation of the TNF-α gene could be considered an important potential genetic marker of ETEC F18 resistance.

  15. Stereotactic Comparison Study of (18)F-Alfatide and (18)F-FDG PET Imaging in an LLC Tumor-Bearing C57BL/6 Mouse Model.

    PubMed

    Wei, Yu-Chun; Gao, Yongsheng; Zhang, Jianbo; Fu, Zheng; Zheng, Jinsong; Liu, Ning; Hu, Xudong; Hou, Wenhong; Yu, Jinming; Yuan, Shuanghu

    2016-01-01

    This study aimed to stereotactically compare the PET imaging performance of (18)F-Alfatide ((18)F-ALF-NOTA-PRGD2, denoted as (18)F-Alfatide) and (18)F-fluorodeoxyglucose (FDG) and immunohistochemistry (IHC) staining in Lewis lung carcinoma (LLC) tumor-bearing C57BL/6 mouse model. (18)F-FDG standard uptake values (SUVs) were higher than (18)F-Alfatide SUVs in tumors, most of the normal tissues and organs except for the bladder. Tumor-to-brain, tumor-to-lung, and tumor-to-heart ratios of (18)F-Alfatide PET were significantly higher than those of (18)F-FDG PET (P < 0.001). The spatial heterogeneity of the tumors was detected, and the tracer accumulation enhanced from the outer layer to the inner layer consistently using the two tracers. The parameters of the tumors were significantly correlated with each other between (18)F-FDG SUV and GLUT-1 (R = 0.895, P < 0.001), (18)F-Alfatide SUV and αvβ3 (R = 0.595, P = 0.019), (18)F-FDG SUV and (18)F-Alfatide SUV (R = 0.917, P < 0.001), and GLUT-1 and αvβ3 (R = 0.637, P = 0.011). Therefore, (18)F-Alfatide PET may be an effective tracer for tumor detection, spatial heterogeneity imaging and an alternative supplement to (18)F-FDG PET, particularly for patients with enhanced characteristics in the brain, chest tumors or diabetes, meriting further study. PMID:27350554

  16. Stereotactic Comparison Study of 18F-Alfatide and 18F-FDG PET Imaging in an LLC Tumor-Bearing C57BL/6 Mouse Model

    PubMed Central

    Wei, Yu-Chun; Gao, Yongsheng; Zhang, Jianbo; Fu, Zheng; Zheng, Jinsong; Liu, Ning; Hu, Xudong; Hou, Wenhong; Yu, Jinming; Yuan, Shuanghu

    2016-01-01

    This study aimed to stereotactically compare the PET imaging performance of 18F-Alfatide (18F-ALF-NOTA-PRGD2, denoted as 18F-Alfatide) and 18F-fluorodeoxyglucose (FDG) and immunohistochemistry (IHC) staining in Lewis lung carcinoma (LLC) tumor-bearing C57BL/6 mouse model. 18F-FDG standard uptake values (SUVs) were higher than 18F-Alfatide SUVs in tumors, most of the normal tissues and organs except for the bladder. Tumor-to-brain, tumor-to-lung, and tumor-to-heart ratios of 18F-Alfatide PET were significantly higher than those of 18F-FDG PET (P < 0.001). The spatial heterogeneity of the tumors was detected, and the tracer accumulation enhanced from the outer layer to the inner layer consistently using the two tracers. The parameters of the tumors were significantly correlated with each other between 18F-FDG SUV and GLUT-1 (R = 0.895, P < 0.001), 18F-Alfatide SUV and αvβ3 (R = 0.595, P = 0.019), 18F-FDG SUV and 18F-Alfatide SUV (R = 0.917, P < 0.001), and GLUT-1 and αvβ3 (R = 0.637, P = 0.011). Therefore, 18F-Alfatide PET may be an effective tracer for tumor detection, spatial heterogeneity imaging and an alternative supplement to 18F-FDG PET, particularly for patients with enhanced characteristics in the brain, chest tumors or diabetes, meriting further study. PMID:27350554

  17. Resting-state functional MRI and [18F]-FDG PET demonstrate differences in neuronal activity between commonly used mouse strains.

    PubMed

    Shah, Disha; Deleye, Steven; Verhoye, Marleen; Staelens, Steven; Van der Linden, Annemie

    2016-01-15

    The existence of numerous interesting mouse models of neurological disorders enables the investigation of causal relations between pathological events and the effect of treatment regimes. However, mouse models of a specific neurological disease are often generated using different background strains, which raises the question whether the observed effects are specific to pathology or depend on the used strain. This study used two independent in vivo functional imaging techniques to evaluate whether mouse strain differences exist in functional connectivity (FC) and brain glucose metabolism i.e. indirect measures of neuronal activity. For this purpose, C57BL/6, BALB/C and SJL mice (N=15/group, male) were evaluated using resting-state functional MRI (rsfMRI) and static [18F]-fluorodeoxyglucose Positron Emission Tomography ([18F]-FDG PET). RsfMRI and [18F]-FDG PET data were analyzed with independent component analysis (ICA). FC was quantified by calculating the mean network-specific FC strength and [18F]-FDG uptake was quantified by calculating the mean network-specific standard uptake value corrected for plasma glucose levels and body weight (SUVglu). The ICA results showed spatially similar neurological components in the rsfMRI and [18F]-FDG PET data, suggesting that patterns of metabolic covariance in the mouse brain reflect FC networks. Comparing FC and [18F]-FDG data showed that strain-dependent differences in brain activity exist for several brain networks i.e. the frontal, cingulate, (hypo)thalamus, striatum, and sensorimotor networks. The results of this study have implications for the interpretation of in vivo functional imaging data in mouse models of neurological disorders generated on different background strains.

  18. Effect of Harderian adenectomy on the statistical analyses of mouse brain imaging using positron emission tomography.

    PubMed

    Kim, Minsoo; Woo, Sang-Keun; Yu, Jung Woo; Lee, Yong Jin; Kim, Kyeong Min; Kang, Joo Hyun; Eom, Kidong; Nahm, Sang-Soep

    2014-01-01

    Positron emission tomography (PET) using 2-deoxy-2-[(18)F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.

  19. Imaging local brain function with emission computed tomography

    SciTech Connect

    Kuhl, D.E.

    1984-03-01

    Positron emission tomography (PET) using /sup 18/F-fluorodeoxyglucose (FDG) was used to map local cerebral glucose utilization in the study of local cerebral function. This information differs fundamentally from structural assessment by means of computed tomography (CT). In normal human volunteers, the FDG scan was used to determine the cerebral metabolic response to conrolled sensory stimulation and the effects of aging. Cerebral metabolic patterns are distinctive among depressed and demented elderly patients. The FDG scan appears normal in the depressed patient, studded with multiple metabolic defects in patients with multiple infarct dementia, and in the patients with Alzheimer disease, metabolism is particularly reduced in the parietal cortex, but only slightly reduced in the caudate and thalamus. The interictal FDG scan effectively detects hypometabolic brain zones that are sites of onset for seizures in patients with partial epilepsy, even though these zones usually appear normal on CT scans. The future prospects of PET are discussed.

  20. Predictive and prognostic value of FDG-PET

    PubMed Central

    Oyen, Wim J.G.

    2008-01-01

    Abstract The predictive and prognostic value of fluorodeoxyglucose (FDG)-positron emission tomography (PET) in non-small-cell lung carcinoma, colorectal carcinoma and lymphoma is discussed. The degree of FDG uptake is of prognostic value at initial presentation, after induction treatment prior to resection and in the case of relapse of non-small cell lung cancer (NSCLC). In locally advanced and advanced stages of NSCLC, FDG-PET has been shown to be predictive for clinical outcome at an early stage of treatment. In colorectal carcinoma, limited studies are available on the prognostic value of FDG-PET, however, the technique appears to have great potential in monitoring the success of local ablative therapies soon after intervention and in the prediction and evaluation of response to radiotherapy, systemic therapy, and combinations thereof. The prognostic value of end-of treatment FDG-PET for FDG-avid lymphomas has been established, and the next step is to define how to use this information to optimize patient outcome. In Hodgkin's lymphoma, FDG-PET has a high negative predictive value, however, histological confirmation of positive findings should be sought where possible. For non-Hodgkin's lymphoma, the opposite applies. The newly published standardized guidelines for interpretation formulates specific criteria for visual interpretation and for defining PET positivity in the liver, spleen, lung, bone marrow and small residual lesions. The introduction of these guidelines should reduce variability among studies. Interim PET offers a reliable method for early prediction of long-term remission, however it should only be performed in prospective randomized controlled trials. Many of the diagnostic and management questions considered in this review are relevant to other tumour types. Further research in this field is of great importance, since it may lead to a change in the therapeutic concept of cancer. The preliminary findings call for systematic inclusion of FDG

  1. FDG PET/CT in serous psammocarcinoma of the ovary.

    PubMed

    Dong, Aisheng; Wang, Yang; Zuo, Changjing

    2014-05-01

    Serous psammocarcinoma of the ovary is a rare variant of ovarian serous carcinoma with a favorable prognosis. We present a case of bilateral ovarian serous psammocarcinoma showing extensive calcification in the primary and disseminated lesions with intense FDG uptake on FDG PET/CT. It may be difficult to differentiate the extensively calcified omental and peritoneal metastases from benign calcified lesions on CT images. This case indicates FDG PET/CT may have an advantage over conventional CT in differentiating malignant calcification from benign calcification based on glucose metabolic activity, and may be helpful for diagnosis and staging of this rare ovarian tumor.

  2. Increased FDG activity in a dermatofibroma in esophageal cancer patient.

    PubMed

    Bingham, Brigid A; Hatef, Daniel A; Chevez-Barrios, Patricia; Blackmon, Shanda H; Kim, Min P

    2013-03-01

    PET using the radiotracer (18)F-FDG is used for staging patients with esophageal cancer. Nonmalignant conditions, mainly inflammation and some benign tumors, however, can cloud the clinical picture by taking up FDG and producing a false-positive result. We report the case of a 46 year-old man with squamous cell carcinoma of the thoracic esophagus who underwent combined PET/CT and had false-positive uptake in a chest wall dermatofibroma. Dermatofibroma is a benign skin lesion with a characteristic large presence of fibroblasts and macrophages. Macrophage uptake of FDG is likely responsible for the false-positive result on PET/CT. PMID:23357820

  3. Delineation of Gross Tumor Volume (GTV) for Radiation Treatment Planning of Locally Advanced Rectal Cancer Using Information From MRI or FDG-PET/CT: A Prospective Study

    SciTech Connect

    Braendengen, Morten; Hansson, Karl; Radu, Calin; Siegbahn, Albert; Jacobsson, Hans; Glimelius, Bengt

    2011-11-15

    Purpose: Accurate delineation of target volumes is important to maximize radiation dose to the tumor and minimize it to nontumor tissue. Computed tomography (CT) and magnetic resonance imaging (MRI) are standard imaging modalities in rectal cancer. The aim was to explore whether functional imaging with F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET), combined with CT (FDG-PET/CT) gives additional information to standard pretreatment evaluation and changes the shape and size of the gross tumor volume (GTV). Methods and Materials: From 2007 to 2009, 77 consecutive patients with locally advanced rectal cancer were prospectively screened for inclusion in the study at two university hospitals in Sweden, and 68 patients were eligible. Standard GTV was delineated using information from clinical examination, CT, and MRI (GTV-MRI). Thereafter, a GTV-PET was defined in the fused PET-CT, and the target volume delineations were compared for total volume, overlap, and mismatch. Pathologic uptake suspect of metastases was also registered. Results: The median volume of GTV-MRI was larger than that of GTV-PET: 111 cm{sup 3} vs. 87 cm{sup 3} (p < 0.001). In many cases, the GTV-MRI contained the GTV defined on the PET/CT images as subvolumes, but when a GTV total was calculated after the addition of GTV-PET to GTV-MRI, the volume increased, with median 11% (range, 0.5-72%). New lesions were seen in 15% of the patients for whom PET/CT was used. Conclusions: FDG-PET/CT facilitates and adds important information to the standard delineation procedure of locally advanced rectal cancer, mostly resulting in a smaller GTV, but a larger total GTV using the union of GTV-MRI and GTV-PET. New lesions were sometimes seen, potentially changing the treatment strategy.

  4. F-18 labeled 3-fluorodiazepam

    SciTech Connect

    Luxen, A.; Barrio, J.R.; Bida, G.T.; Satyamurthy, N.; Phelps, M.E.

    1985-05-01

    3-Fluorodiazepam is a new and potent antianxiety agent with prolonged action. The authors found that molecular fluorine (0.5% in Ne) reacts cleanly with diazepam in freon or chloroform at room temperature to produce 3-fluorodiazepam in good yields. Successful syntheses have employed 2:1 to 5:1 molar ratios diazepam: fluorine to minimize the formation of byproducts. (/sup 18/F) 3-Fluorodiazepam, a potential candidate for PET studies, (specific activity 3-5 Ci/mmol) has been synthesized from /sup 18/F-F/sub 2/ using the same procedure, followed by column chromatographic purification (Silicagel, dichloromethane: ethyl acetate, 5:1) with a radiochemical yield of 12-20% (50% maximum) and a chemical and radiochemical purity >99% as judged by reversed-phase high pressure liquid chromatography analysis (Ultrasyl octyl column, 10 ..mu.. m, 4.6 x 250 mm i.d., 60% MeOH 40% water; flow rate, 1.0 ml/min; retention time for (/sup 18/F) fluorodiazepam, 11.4 min; for diazepam, 13.5 min; radioactivity and ultraviolet detectors). Lower radiochemical yields (5-7%), and significant formation of by-products were observed when (/sup 18/F)acetylhypofluorite, prepared in the gasphase, was used as the reagent. Readily accessible routes to /sup 18/F-labeled benzodiazepines of higher specific activity were also investigated. Approaches to the synthesis of high specific activity (>200 Ci/mmol) (/sup 18/F)3-fluorodiazepam involve nucleophilic displacement at carbon-3 (e.g. from 3-chlorodiazepam) with (/sup 18/F)fluoride ion. The results presented here demonstrate the synthetic accessibility of /sup 18/F-labeled benzodiazepines for application in neurotransmitter ligand studies with PET.

  5. Conjugative IncF and IncI1 plasmids with tet(A) and class 1 integron conferring multidrug resistance in F18(+) porcine enterotoxigenic E. coli.

    PubMed

    Szmolka, Ama; Lestár, Barbara; Pászti, Judit; Fekete, Péter; Nagy, Béla

    2015-12-01

    Enterotoxigenic E. coli (ETEC) bacteria frequently cause watery diarrhoea in newborn and weaned pigs. Plasmids carrying genes of different enterotoxins and fimbrial adhesins, as well as plasmids conferring antimicrobial resistance are of prime importance in the epidemiology and pathogenesis of ETEC. Recent studies have revealed the significance of the porcine ETEC plasmid pTC, carrying tetracycline resistance gene tet(B) with enterotoxin genes. In contrast, the role of tet(A) plasmids in transferring resistance of porcine ETEC is less understood. The objective of the present study was to provide a comparative analysis of antimicrobial resistance and virulence gene profiles of porcine post-weaning ETEC strains representing pork-producing areas in Central Europe and in the USA, with special attention to plasmids carrying the tet(A) gene. Antimicrobial resistance phenotypes and genotypes of 87 porcine ETEC strains isolated from cases of post-weaning diarrhoea in Austria, the Czech Republic, Hungary and the Midwest USA was determined by disk diffusion and by PCR. Central European strains carrying tet(A) or tet(B) were further subjected to molecular characterisation of their tet plasmids. Results indicated that > 90% of the ETEC strains shared a common multidrug resistant (MDR) pattern of sulphamethoxazole (91%), tetracycline (84%) and streptomycin (80%) resistance. Tetracycline resistance was most frequently determined by the tet(B) gene (38%), while tet(A) was identified in 26% of all isolates with wide ranges for both tet gene types between some countries and with class 1 integrons and resistance genes co-transferred by conjugation. The virulence gene profiles included enterotoxin genes (lt, sta and/or stb), as well as adhesin genes (k88/f4, f18). Characterisation of two representative tet(A) plasmids of porcine F18(+) ETEC from Central Europe revealed that the IncF plasmid (pES11732) of the Czech strain (~120 kb) carried tet(A) in association with catA1 for

  6. Conjugative IncF and IncI1 plasmids with tet(A) and class 1 integron conferring multidrug resistance in F18(+) porcine enterotoxigenic E. coli.

    PubMed

    Szmolka, Ama; Lestár, Barbara; Pászti, Judit; Fekete, Péter; Nagy, Béla

    2015-12-01

    Enterotoxigenic E. coli (ETEC) bacteria frequently cause watery diarrhoea in newborn and weaned pigs. Plasmids carrying genes of different enterotoxins and fimbrial adhesins, as well as plasmids conferring antimicrobial resistance are of prime importance in the epidemiology and pathogenesis of ETEC. Recent studies have revealed the significance of the porcine ETEC plasmid pTC, carrying tetracycline resistance gene tet(B) with enterotoxin genes. In contrast, the role of tet(A) plasmids in transferring resistance of porcine ETEC is less understood. The objective of the present study was to provide a comparative analysis of antimicrobial resistance and virulence gene profiles of porcine post-weaning ETEC strains representing pork-producing areas in Central Europe and in the USA, with special attention to plasmids carrying the tet(A) gene. Antimicrobial resistance phenotypes and genotypes of 87 porcine ETEC strains isolated from cases of post-weaning diarrhoea in Austria, the Czech Republic, Hungary and the Midwest USA was determined by disk diffusion and by PCR. Central European strains carrying tet(A) or tet(B) were further subjected to molecular characterisation of their tet plasmids. Results indicated that > 90% of the ETEC strains shared a common multidrug resistant (MDR) pattern of sulphamethoxazole (91%), tetracycline (84%) and streptomycin (80%) resistance. Tetracycline resistance was most frequently determined by the tet(B) gene (38%), while tet(A) was identified in 26% of all isolates with wide ranges for both tet gene types between some countries and with class 1 integrons and resistance genes co-transferred by conjugation. The virulence gene profiles included enterotoxin genes (lt, sta and/or stb), as well as adhesin genes (k88/f4, f18). Characterisation of two representative tet(A) plasmids of porcine F18(+) ETEC from Central Europe revealed that the IncF plasmid (pES11732) of the Czech strain (~120 kb) carried tet(A) in association with catA1 for

  7. Management of Large-Vessel Vasculitis With FDG-PET

    PubMed Central

    Soussan, Michael; Nicolas, Patrick; Schramm, Catherine; Katsahian, Sandrine; Pop, Gabriel; Fain, Olivier; Mekinian, Arsene

    2015-01-01

    Abstract We aimed to clarify the role of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in the management of large-vessel vasculitis (LVV), focusing on 3 issues which are as follows: describe and determine the different FDG-PET criteria for the diagnosis of vascular inflammation, the performance of FDG-PET for the diagnosis of large-vessel inflammation in giant cell arteritis (GCA) patients, and the performance of FDG-PET to evaluate the disease inflammatory activity in Takayasu arteritis (TA) patients. MEDLINE, Cochrane Library, and EMBASE database were searched for articles that evaluated the value of FDG-PET in LVV, from January 2000 to December 2013. Inclusion criteria were American College of Rheumatology criteria for GCA or TA, definition PET positivity threshold, and >4 cases included. Sensitivity (Se) and specificity (Sp) of FDG-PET for the diagnosis of large-vessel inflammation were calculated from each included individual study, and then pooled for meta-analysis with a random-effects model. Twenty-one studies (413 patients, 299 controls) were included in the systematic review. FDG-PET showed FDG vascular uptake in 70% (288/413) of patients and 7% (22/299) of controls. Only vascular uptake equal to or higher than the liver uptake was significantly different between GCA/TA patients and controls (P < 0.001). The meta-analysis of GCA patients (4 studies, 57 patients) shows that FDG-PET has high Se and Sp for the diagnosis of large-vessel inflammation in GCA patients in comparison to controls, with a pooled Se at 90% (95% confidence interval [CI], 79%–93%) and a pooled Sp at 98% (95% CI, 94%–99%). The meta-analysis of TA patients (7 studies, 191 patients) shows that FDG-PET has a pooled Se at 87% (95% CI, 78%–93%) and Sp at 73% (95% CI, 63%–81%) for the assessment of disease activity in TA, with up to 84% Sp, with studies using National Institutes of Health criteria as the disease activity assessment scale. FDG-PET showed good

  8. Diminished glucose transport and phosphorylation in Alzheimer`s disease determined by dynamic FDG-PET

    SciTech Connect

    Piert, M.; Koeppe, R.A.; Giordani, B.; Berent, S.; Kuhl, D.E.

    1996-02-01

    Using dynamic [{sup 18}F] fluorodeoxyglucose (FDG) and PET, kinetic rate constants that describe influx (K{sub 1}) and efflux (k{sub 2}) of FDG as well s phosphorylation (k{sub 3}) and dephosphorylation (k{sub 4}) were determined in patients with probable Alzheimer`s disease and similarly aged normal controls. The regional cerebral metabolic rate for glucose (CMR{sub glu}) was calculated from individually fitted rate constants in frontal, temporal, parietal and occipital cerebral cortex, caudate nucleus, putamen, thalamus and cerebellar cortex. Dynamic PET scans were obtained in normal controls (n = 10, mean age = 67) and Alzheimer`s disease patients (n = 8, mean age = 67) for 60 min following injection of 10 mCi of FDG. The Alzheimer`s disease group was characterized by decreases of the CMR{sub glu} ranging from 13.3% in the frontal to 40.9% in the parietal cortex, which achieved significance in all regions except the thalamus. K{sub 1} was significantly reduced in the parietal (p < 0.01) and temporal cortices (p < 0.005), temporal and occipital cortex, and in the putamen and cerebellum (p < 0.05). The rate constants k{sub 2} and k{sub 4} were unchanged in the Alzheimer`s disease group. These data suggest that hypometabolism in Alzheimer`s disease is related to reduced glucose phosphorylation activity as well as diminished glucose transport, particularly in the most metabolically affected areas of the brain, the parietal and temporal cortex. 60 refs., 2 figs., 2 tabs.

  9. Flight-Determined Subsonic Longitudinal Stability and Control Derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) with Thrust Vectoring

    NASA Technical Reports Server (NTRS)

    Iliff, Kenneth W.; Wang, Kon-Sheng Charles

    1997-01-01

    The subsonic longitudinal stability and control derivatives of the F-18 High Angle of Attack Research Vehicle (HARV) are extracted from dynamic flight data using a maximum likelihood parameter identification technique. The technique uses the linearized aircraft equations of motion in their continuous/discrete form and accounts for state and measurement noise as well as thrust-vectoring effects. State noise is used to model the uncommanded forcing function caused by unsteady aerodynamics over the aircraft, particularly at high angles of attack. Thrust vectoring was implemented using electrohydraulically-actuated nozzle postexit vanes and a specialized research flight control system. During maneuvers, a control system feature provided independent aerodynamic control surface inputs and independent thrust-vectoring vane inputs, thereby eliminating correlations between the aircraft states and controls. Substantial variations in control excitation and dynamic response were exhibited for maneuvers conducted at different angles of attack. Opposing vane interactions caused most thrust-vectoring inputs to experience some exhaust plume interference and thus reduced effectiveness. The estimated stability and control derivatives are plotted, and a discussion relates them to predicted values and maneuver quality.

  10. Spin-Tunnel Investigation of a 1/28-Scale Model of the NASA F-18 High Alpha Research Vehicle (HARV) with and without Vertical Tails

    NASA Technical Reports Server (NTRS)

    Fremaux, C. Michael

    1997-01-01

    An investigation was conducted in the NASA Langley 20-Foot Vertical Spin Tunnel to determine the developed spin and spin-recovery characteristics of a 1/28-scale, free-spinning model of the NASA F-18 HARV (High Alpha Research Vehicle) airplane that can configured with and without the vertical tails installed. The purpose of the test was to determine what effects, if any, the absence of vertical tails (and rudders) had on the spin and spin-recovery capabilities of the HARV. The model was ballasted to dynamically represent the full-scale airplane at an altitude of 25,000 feet. Erect and inverted spin tests with symmetric mass loadings were conducted with the free-spinning model. The model results indicate that the basic airplane with vertical tails installed (with unaugmented control system) will exhibit fast, flat erect and inverted spins from which acceptable recoveries can be made. Removing the vertical tails had little effect on the erect spin mode, but did degrade recoveries from erect spins. In contrast, inverted spins without the vertical tails were significantly more severe than those with the tails installed.

  11. Verbal Memory Deficits Are Correlated with Prefrontal Hypometabolism in 18FDG PET of Recreational MDMA Users

    PubMed Central

    Bosch, Oliver G.; Wagner, Michael; Jessen, Frank; Kühn, Kai-Uwe; Joe, Alexius; Seifritz, Erich; Maier, Wolfgang; Biersack, Hans-Jürgen; Quednow, Boris B.

    2013-01-01

    Introduction 3,4-Methylenedioxymethamphetamine (MDMA, “ecstasy”) is a recreational club drug with supposed neurotoxic effects selectively on the serotonin system. MDMA users consistently exhibit memory dysfunction but there is an ongoing debate if these deficits are induced mainly by alterations in the prefrontal or mediotemporal cortex, especially the hippocampus. Thus, we investigated the relation of verbal memory deficits with alterations of regional cerebral brain glucose metabolism (rMRGlu) in recreational MDMA users. Methods Brain glucose metabolism in rest was assessed using 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography (18FDG PET) in 19 male recreational users of MDMA and 19 male drug-naïve controls. 18FDG PET data were correlated with memory performance assessed with a German version of the Rey Auditory Verbal Learning Test. Results As previously shown, MDMA users showed significant impairment in verbal declarative memory performance. PET scans revealed significantly decreased rMRGlu in the bilateral dorsolateral prefrontal and inferior parietal cortex, bilateral thalamus, right hippocampus, right precuneus, right cerebellum, and pons (at the level of raphe nuclei) of MDMA users. Among MDMA users, learning and recall were positively correlated with rMRGlu predominantly in bilateral frontal and parietal brain regions, while recognition was additionally related to rMRGlu in the right mediotemporal and bihemispheric lateral temporal cortex. Moreover, cumulative lifetime dose of MDMA was negatively correlated with rMRGlu in the left dorsolateral and bilateral orbital and medial PFC, left inferior parietal and right lateral temporal cortex. Conclusions Verbal learning and recall deficits of recreational MDMA users are correlated with glucose hypometabolism in prefrontal and parietal cortex, while word recognition was additionally correlated with mediotemporal hypometabolism. We conclude that memory deficits of MDMA users arise from combined

  12. A FDG-PET Study of Metabolic Networks in Apolipoprotein E ε4 Allele Carriers.

    PubMed

    Yao, Zhijun; Hu, Bin; Zheng, Jiaxiang; Zheng, Weihao; Chen, Xuejiao; Gao, Xiang; Xie, Yuanwei; Fang, Lei

    2015-01-01

    Recently, some studies have applied the graph theory in brain network analysis in Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). However, relatively little research has specifically explored the properties of the metabolic network in apolipoprotein E (APOE) ε4 allele carriers. In our study, all the subjects, including ADs, MCIs and NCs (normal controls) were divided into 165 APOE ε4 carriers and 165 APOE ε4 noncarriers. To establish the metabolic network for all brain regions except the cerebellum, cerebral glucose metabolism data obtained from FDG-PET (18F-fluorodeoxyglucose positron emission tomography) were segmented into 90 areas with automated anatomical labeling (AAL) template. Then, the properties of the networks were computed to explore the between-group differences. Our results suggested that both APOE ε4 carriers and noncarriers showed the small-world properties. Besides, compared with APOE ε4 noncarriers, the carriers showed a lower clustering coefficient. In addition, significant changes in 6 hub brain regions were found in between-group nodal centrality. Namely, compared with APOE ε4 noncarriers, significant decreases of the nodal centrality were found in left insula, right insula, right anterior cingulate, right paracingulate gyri, left cuneus, as well as significant increases in left paracentral lobule and left heschl gyrus in APOE ε4 carriers. Increased local short distance interregional correlations and disrupted long distance interregional correlations were found, which may support the point that the APOE ε4 carriers were more similar with AD or MCI in FDG uptake. In summary, the organization of metabolic network in APOE ε4 carriers indicated a less optimal pattern and APOE ε4 might be a risk factor for AD.

  13. Right Limbic FDG-PET Hypometabolism Correlates with Emotion Recognition and Attribution in Probable Behavioral Variant of Frontotemporal Dementia Patients

    PubMed Central

    Cerami, Chiara; Dodich, Alessandra; Iannaccone, Sandro; Marcone, Alessandra; Lettieri, Giada; Crespi, Chiara; Gianolli, Luigi; Cappa, Stefano F.; Perani, Daniela

    2015-01-01

    The behavioural variant of frontotemporal dementia (bvFTD) is a rare disease mainly affecting the social brain. FDG-PET fronto-temporal hypometabolism is a supportive feature for the diagnosis. It may also provide specific functional metabolic signatures for altered socio-emotional processing. In this study, we evaluated the emotion recognition and attribution deficits and FDG-PET cerebral metabolic patterns at the group and individual levels in a sample of sporadic bvFTD patients, exploring the cognitive-functional correlations. Seventeen probable mild bvFTD patients (10 male and 7 female; age 67.8±9.9) were administered standardized and validated version of social cognition tasks assessing the recognition of basic emotions and the attribution of emotions and intentions (i.e., Ekman 60-Faces test-Ek60F and Story-based Empathy task-SET). FDG-PET was analysed using an optimized voxel-based SPM method at the single-subject and group levels. Severe deficits of emotion recognition and processing characterized the bvFTD condition. At the group level, metabolic dysfunction in the right amygdala, temporal pole, and middle cingulate cortex was highly correlated to the emotional recognition and attribution performances. At the single-subject level, however, heterogeneous impairments of social cognition tasks emerged, and different metabolic patterns, involving limbic structures and prefrontal cortices, were also observed. The derangement of a right limbic network is associated with altered socio-emotional processing in bvFTD patients, but different hypometabolic FDG-PET patterns and heterogeneous performances on social tasks at an individual level exist. PMID:26513651

  14. FDG-PET/CT in the evaluation of anal carcinoma

    SciTech Connect

    Cotter, Shane E.; Grigsby, Perry W. . E-mail: pgrigsby@wustl.edu; Siegel, Barry A.

    2006-07-01

    Purpose: Surgical staging and treatment of anal carcinoma has been replaced by noninvasive staging studies and combined modality therapy. In this study, we compare computed tomography (CT) and physical examination to [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in the staging of carcinoma of the anal canal, with special emphasis on determination of spread to inguinal lymph nodes. Methods and Materials: Between July 2003 and July 2005, 41 consecutive patients with biopsy-proved anal carcinoma underwent a complete staging evaluation including physical examination, CT, and 2-FDG-PET/CT. Patients ranged in age from 30 to 89 years. Nine men were HIV-positive. Treatment was with standard Nigro regimen. Results: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) detected 91% of nonexcised primary tumors, whereas CT visualized 59%. FDG-PET/CT detected abnormal uptake in pelvic nodes of 5 patients with normal pelvic CT scans. FDG-PET/CT detected abnormal nodes in 20% of groins that were normal by CT, and in 23% without abnormality on physical examination. Furthermore, 17% of groins negative by both CT and physical examination showed abnormal uptake on FDG-PET/CT. HIV-positive patients had an increased frequency of PET-positive lymph nodes. Conclusion: [{sup 18}F]-fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography detects the primary tumor more often than CT. FDG-PET/CT detects substantially more abnormal inguinal lymph nodes than are identified by standard clinical staging with CT and physical examination.

  15. Functional imaging of the brain with/sup 18/F-fluorodeoxyglucose

    SciTech Connect

    Reivich, M; Greenberg, J; Alavi, A; Hand, P; Rintelmann, W; Rosenquist, A; Christman, D; Fowler, J; MacGregor, R; Wolf, A

    1980-01-01

    A techniques is reported by which it is possible to determine which regions of the human brain become functionally active in response to a specific stimulus. The method utilizes /sup 18/F-2-fluoro-2-deoxyglucose ((/sup 18/F)-FDG) administered as a bolus. (/sup 18/F)-FDG is used as a tracer for the exchange of glucose between plasma and brain and its phosphorylation. The subject is then scanned during administration of a physiologic stimulus by position emission tomography and the three-dimensional distribution of /sup 18/F activity in the brain determined. (ACR)

  16. Detection of Leptomeningeal Involvement by 18F-FDG-PET/CT in a Patient With Non-Hodgkin Lymphoma.

    PubMed

    Fonti, Rosa; Salvatore, Barbara; De Renzo, Amalia; Nicolai, Emanuele; Del Vecchio, Silvana

    2016-02-01

    Leptomeningeal infiltration of the brain or spinal cord by neoplastic cells may occur as complication of solid or hematopoietic tumors such as non-Hodgkin lymphoma. Previously rare, this event is becoming increasingly common as newer therapies can prolong survival but may not achieve therapeutic concentration in the central nervous system. Although prognosis is poor, early diagnosis and aggressive treatment may lead to prolonged survival and/or improvement of quality of life. We report a case of a 69-year-old man with leptomeningeal infiltration by non-Hodgkin lymphoma revealed by F-FDG-PET/CT and confirmed by subsequent spinal MRI and cerebrospinal fluid cytology. PMID:26545028

  17. Radiation-induced osteosarcoma might mimic metastatic bone lesions: a case with bone scan and FDG PET/CT imaging.

    PubMed

    Koyama, Masamichi; Koizumi, Mitsuru; Umayahara, Kenji; Takeshima, Nobuhiro; Takahashi, Shunji

    2015-05-01

    We report on a 53-year-old woman with osteosarcoma of the skull who underwent radiation therapy for metastatic brain tumor. She had a history of uterine endometrial cancer treated with chemotherapy and surgery 9 years previously. FDG PET/CT for surveillance showed nodular accumulation at the right suprainguinal region and very avid accumulation at the left side of the occipital bone. Bone scan showed increased accumulation at the same portion of the occipital bone. The occipital tumor was surgically removed and diagnosed as radiation-induced osteosarcoma.

  18. FDG-PET evaluation of indeterminate pancreatic masses

    SciTech Connect

    Ho, Chi-Lai; Dehdashti, Farrokh; Griffeth, L.K.

    1996-05-01

    The purpose of this study was to assess the-ability of PET with 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (FDG) to differentiate benign from malignant pancreatic masses in patients with indeterminate findings on CT. We performed FDG-PET on 12 patients with indeterminate mass lesions and 2 patients with CT findings typical for malignancy. Eight were found to have pancreatic carcinoma and six had benign lesions. The final diagnosis was histopathologically confirmed in all patients but two with a presumed diagnosis of focal pancreatitis based on stable clinical follow-up for at least 12 months. Lesion uptake of FDG was evaluated qualitatively and semi-quantitatively by determination of the standardized uptake value (SUV). With use of a 2.5 cutoff value for SUV, all eight malignant and four of six benign lesions were correctly categorized. Qualitative evaluation gave the same results. The two false-positive lesions had elevated SUV values of 3.4 and 3.8, respectively. Our results indicate that FDG-PET has potential value for assessing patients with CT findings that are indeterminate for pancreatic carcinoma. FDG-PET may obviate invasive diagnostic procedures in many patients with benign disease. 36 refs., 2 figs., 1 tab.

  19. FDG-PET/CT in pediatric solid tumors.

    PubMed

    Franzius, C

    2010-08-01

    Positron emission tomography/computed tomography (PET/CT) has become an important imaging modality in the non-invasive evaluation and monitoring of children with known or suspected malignant diseases. In sarcoma patients, [18F]FDG (FDG) PET and FDG PET/CT is useful in staging, therapy monitoring, and detection of relapse. However, FDG PET has been proven to be less sensitive than chest CT in the detection of pulmonary metastases derived from sarcoma. This disadvantage has been overcome using a PET/CT scanner. In neuroblastoma patients, PET using FDG is indicated in MIBG-negative cases. Furthermore, there are specific PET tracers for tumors of the sympathetic nervous system, such as [11C]Hydroxyephedrine (HED) and [18F]-labeled dihydrophenylalanine (F-DOPA), which can be used for PET/CT imaging for detection of disease, staging and monitoring therapy. However, there are only few studies using specific PET tracers in neuroblastoma patients. In other pediatric malignancies including germ cell tumors and hepatoblastoma PET and PET/CT may be helpful in individual cases, but the literature in these entities is limited so far. Although publications on the additional value of the combined PET/CT compared to both stand-alone modalities are still limited in pediatrics, it can already be anticipated that the combination of morphological and functional information obtained by integrated PET/CT will improve the accuracy of staging and will change patient management in a significant number of pediatric patients.

  20. The use of fluorine-18 fluorodeoxyglucose positron emission tomography for imaging human motor neuronal activation in the brain

    PubMed Central

    PAHK, KISOO; PARK, KUN-WOO; PYUN, SUNG BOM; LEE, JAE SUNG; KIM, SUNGEUN; CHOE, JAE GOL

    2015-01-01

    The present study aimed to visualize human motor neuronal activation in the brain using fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), and to develop an FDG-PET procedure for imaging neuronal activation. A male volunteer underwent 20 min periods of rest and motor activation, whilst being assessed using FDG-PET on two consecutive days. The motor task, which involved repetitively grasping and releasing the right hand, was performed during the initial 5 min of the activation period. Subtraction of the rest period signal from the activation PET images was performed using the subtraction ictal single-photon emission computed tomography co-registered to magnetic resonance imaging method. The subtracted image detected activation of the contralateral (left) primary motor cortex, supplementary motor area, and ipsilateral (right) cerebellum. In the present study, FDG-PET detected significantly increased motor-associated activation of the brain in a subject performing a motor task. PMID:26668604

  1. IMPROVED DERIVATION OF INPUT FUNCTION IN DYNAMIC MOUSE [18F]FDG PET USING BLADDER RADIOACTIVITY KINETICS

    PubMed Central

    Wong, Koon-Pong; Zhang, Xiaoli; Huang, Sung-Cheng

    2013-01-01

    Purpose Accurate determination of the plasma input function (IF) is essential for absolute quantification of physiological parameters in positron emission tomography (PET). However, it requires an invasive and tedious procedure of arterial blood sampling that is challenging in mice because of the limited blood volume. In this study, a hybrid modeling approach is proposed to estimate the plasma IF of 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) in mice using accumulated radioactivity in urinary bladder together with a single late-time blood sample measurement. Methods Dynamic PET scans were performed on nine isoflurane-anesthetized male C57BL/6 mice after a bolus injection of [18F]FDG at the lateral caudal vein. During a 60- or 90-min scan, serial blood samples were taken from the femoral artery. Image data were reconstructed using filtered backprojection with CT-based attenuation correction. Total accumulated radioactivity in the urinary bladder was fitted to a renal compartmental model with the last blood sample and a 1-exponential function that described the [18F]FDG clearance in blood. Multiple late-time blood sample estimates were calculated by the blood [18F]FDG clearance equation. A sum of 4-exponentials was assumed for the plasma IF that served as a forcing function to all tissues. The estimated plasma IF was obtained by simultaneously fitting the [18F]FDG model to the time-activity curves (TACs) of liver and muscle and the forcing function to early (0–1 min) left-ventricle data (corrected for delay, dispersion, partial-volume effects and erythrocytes uptake) and the late-time blood estimates. Using only the blood sample acquired at the end of the study to estimate the IF and the use of liver TAC as an alternative IF were also investigated. Results The area under the plasma TACs calculated for all studies using the hybrid approach was not significantly different from that using all blood samples. [18F]FDG uptake constants in brain, myocardium, skeletal

  2. Unusual involvement of scalp and bilateral kidneys in an aggressive mediastinal diffuse large B cell lymphoma: documentation by FDG-PET imaging.

    PubMed

    Basu, Sandip; Ramani, S K; Lad, S

    2009-09-01

    In the present communication, an unusual combination of scalp soft tissue and underlying brain involvement with intact skull bone coupled with bilateral renal involvement from a mediastinal diffuse large B cell lymphoma (DLBL) is presented. A 45-year-old man, a diagnosed case of mediastinal DLBL with bilateral lung involvement, was treated with conventional 6 cycles of chemotherapy and local external radiotherapy with initial good treatment response evidenced by considerable regression in mass size and regression in pulmonary lesions. Three months later, he returned with complaints of soft tissue swelling over the scalp; one of them in the high parietal bone and the other over the occipital region. A whole body FDG-PET at this time showed 2 moderate-sized foci in the scalp (with preservation of both tables of skull bone) and corresponding large foci in the brain parenchyma beneath, a superior mediastinal focus, a few foci in the apical and lower zone of left lung, extensive irregular uptake in the right pleura and the right lung parenchyma coupled with a loculated effusion in its lower zone and studded foci of hypermetabolism throughout the bilaterally enlarged kidneys. CT of the head confirmed the FDG-PET findings and histopathology of the biopsy from the scalp swelling was suggestive of DLBL. Ultrasound imaging of the abdomen showed lobulated bilaterally enlarged kidneys with multiple hypoechoic areas within them. The patient underwent palliative local external radiotherapy to the brain and systemic chemotherapy with poor clinical results with raised serum beta-2 microglobulin and serum LDH levels and deranged renal function. The patient died within a month after the FDG-PET study. The event of scalp and bilateral renal involvement from DLBL is rare in lymphoma literature and this report highlights that such unusual events can occur as part of widespread dissemination and underscores the importance of whole-body imaging with FDG-PET. PMID:19692836

  3. Reduced uptake of 18F-FDG and 15O-H2O in Alzheimer's disease-related regions after glucose loading.

    PubMed

    Ishibashi, Kenji; Kawasaki, Keiichi; Ishiwata, Kiichi; Ishii, Kenji

    2015-08-01

    Increased plasma glucose levels are known to reduce fluorine-18-labeled fluorodeoxyglucose ((18)F-FDG) uptake in Alzheimer's disease (AD)-related regions, resulting in the appearance of an AD-like pattern. However, the relationships of its appearance with cerebral blood flow and insulin levels are uncertain. We performed (18)F-FDG and oxygen-15-labeled water ((15)O-H2O) positron emission tomography in the fasting and glucose-loading conditions on nine young healthy volunteers with no cognitive impairments. Measurement of plasma glucose and insulin levels confirmed that all subjects were free of insulin resistance, and that glucose loading significantly increased plasma glucose and insulin levels. Fluorine-18-labeled fluorodeoxyglucose and (15)O-H2O images were compared between the two conditions, focusing on AD-related regions: precuneus/posterior cingulate (PP), lateral parietal cortex (LPC), and frontal cortex (FC). Volume-of-interest analyses showed significantly lower uptake of both (18)F-FDG and (15)O-H2O in PP, LPC, and FC after glucose loading (P<0.05). Whole-brain voxel-wise analyses also revealed the PP, LPC, and FC areas where uptake of both (18)F-FDG and (15)O-H2O decreased (P<0.05, familywise error rate-corrected). We concluded that increased plasma glucose and insulin levels can cause the appearance of the AD-like pattern in both (18)F-FDG and (15)O-H2O images, and this phenomenon can occur even in subjects without insulin resistance. PMID:26058692

  4. Pulmonary lymphangitic carcinomatosis (PLC): spectrum of FDG-PET findings.

    PubMed

    Acikgoz, Gunsel; Kim, Sung M; Houseni, Mohamed; Cermik, Tevfik F; Intenzo, Charles M; Alavi, Abass

    2006-11-01

    The lungs are among the most common sites for metastases from a multitude of cancers. The majority of pulmonary metastases appear nodular on radiologic images. Interstitial spread of tumor through pulmonary lymphatics, also known as pulmonary lymphangitic carcinomatosis (PLC), is not uncommon and constitutes approximately 7% of pulmonary metastases. PLC is most often seen with adenocarcinoma of a variety of histologies such as thyroid carcinoma, and melanoma. It is usually noted in late stages of malignancy and therefore is indicative of a poor prognosis. Diagnosis of PLC is usually based on a combination of clinical and radiologic findings. However, the diagnosis is difficult when patients have limited clinical findings or have a history of or the possibility of other interstitial lung diseases. High-resolution computed tomography (HRCT) has been the modality of choice in the radiologic diagnosis of PLC. Imaging features of PLC on HRCT include thickening of interlobular septa, fissures, and bronchovascular bundles. Distribution of PLC may be focal or diffuse, unilateral or bilateral, and symmetric or asymmetric. Although FDG-PET has been extensively used in primary or secondary lung malignancies, its role and appearance in PLC have not been well determined in the literature. In this communication, we describe a spectrum of FDG-PET and CT findings in 5 cases with PLC. Similar to CT, the distribution of PLC can be extensive or limited on the FDG-PET. Diffuse, lobar, or segmental FDG uptake in the lungs is seen in extensive PLC. In limited PLC, a linear or a hazy area of FDG uptake extending from the tumor can be seen. Recognition of various patterns related to PLC on FDG-PET may allow accurate diagnosis of disease and could potentially influence the management of these patients.

  5. The Basic Principles of FDG-PET/CT Imaging.

    PubMed

    Basu, Sandip; Hess, Søren; Nielsen Braad, Poul-Erik; Olsen, Birgitte Brinkmann; Inglev, Signe; Høilund-Carlsen, Poul Flemming

    2014-10-01

    Positron emission tomography (PET) imaging with 2-[(18)F]fluoro-2-deoxy-D-glucose (FDG) forms the basis of molecular imaging. FDG-PET imaging is a multidisciplinary undertaking that requires close interdisciplinary collaboration in a broad team comprising physicians, technologists, secretaries, radio-chemists, hospital physicists, molecular biologists, engineers, and cyclotron technicians. The aim of this review is to provide a brief overview of important basic issues and considerations pivotal to successful patient examinations, including basic physics, instrumentation, radiochemistry, molecular and cell biology, patient preparation, normal distribution of tracer, and potential interpretive pitfalls. PMID:26050942

  6. High Uptake of FDG Along a Biliary Stent

    PubMed Central

    Nagasaki, Yasunari; Yamane, Hiromichi; Ochi, Nobuaki; Honda, Yoshihiro; Takigawa, Nagio

    2016-01-01

    Abstract A 66-year-old woman presented with abdominal discomfort. Contrast-enhanced CT revealed a mass in the pancreas and multiple liver metastases. Pathological examination confirmed the mass to be primary pancreatic cancer. Endoscopic insertion of a biliary stent was performed to prevent common bile duct obstruction. Subsequently, she received combination chemotherapy, which resulted in a complete response. FDG-PET-CT after chemotherapy revealed a high uptake of FDG along the outline of the biliary stent, with complete disappearance of both the primary and metastatic tumors. PMID:27607171

  7. Ophthalmologic abnormalities on FDG-PET/CT: a pictorial essay

    PubMed Central

    Muzaffar, Razi; Shousha, Mohamed A.; Sarajlic, Lejla

    2013-01-01

    Abstract Positron emission tomography (PET) using [18F]-2-deoxy-d-glucose (FDG) diagnoses, stages, and restages many cancers and is often better than anatomic imaging alone. However, abnormalities within the orbit present a challenge in evaluation, mainly due to the subtle findings on PET/computed tomography (CT). In addition, this region is typically at the edge of the field of view for the standard base of skull to upper thigh FDG-PET/CT scans. The aim of this pictorial essay is to illustrate several subtle and apparent abnormalities within the orbit that can have a profound impact on patient management and follow-up. PMID:23524026

  8. Kinetic quantitation of cerebral PET-FDG studies without concurrent blood sampling: statistical recovery of the arterial input function.

    PubMed

    O'Sullivan, F; Kirrane, J; Muzi, M; O'Sullivan, J N; Spence, A M; Mankoff, D A; Krohn, K A

    2010-03-01

    Kinetic quantitation of dynamic positron emission tomography (PET) studies via compartmental modeling usually requires the time-course of the radio-tracer concentration in the arterial blood as an arterial input function (AIF). For human and animal imaging applications, significant practical difficulties are associated with direct arterial sampling and as a result there is substantial interest in alternative methods that require no blood sampling at the time of the study. A fixed population template input function derived from prior experience with directly sampled arterial curves is one possibility. Image-based extraction, including requisite adjustment for spillover and recovery, is another approach. The present work considers a hybrid statistical approach based on a penalty formulation in which the information derived from a priori studies is combined in a Bayesian manner with information contained in the sampled image data in order to obtain an input function estimate. The absolute scaling of the input is achieved by an empirical calibration equation involving the injected dose together with the subject's weight, height and gender. The technique is illustrated in the context of (18)F -Fluorodeoxyglucose (FDG) PET studies in humans. A collection of 79 arterially sampled FDG blood curves are used as a basis for a priori characterization of input function variability, including scaling characteristics. Data from a series of 12 dynamic cerebral FDG PET studies in normal subjects are used to evaluate the performance of the penalty-based AIF estimation technique. The focus of evaluations is on quantitation of FDG kinetics over a set of 10 regional brain structures. As well as the new method, a fixed population template AIF and a direct AIF estimate based on segmentation are also considered. Kinetics analyses resulting from these three AIFs are compared with those resulting from radially sampled AIFs. The proposed penalty-based AIF extraction method is found to

  9. A multi-center randomized proof-of-concept clinical trial applying [¹⁸F]FDG-PET for evaluation of metabolic therapy with rosiglitazone XR in mild to moderate Alzheimer's disease.

    PubMed

    Tzimopoulou, Sofia; Cunningham, Vincent J; Nichols, Thomas E; Searle, Graham; Bird, Nick P; Mistry, Prafull; Dixon, Ian J; Hallett, William A; Whitcher, Brandon; Brown, Andrew P; Zvartau-Hind, Marina; Lotay, Narinder; Lai, Robert Y K; Castiglia, Mary; Jeter, Barbara; Matthews, Julian C; Chen, Kewei; Bandy, Dan; Reiman, Eric M; Gold, Michael; Rabiner, Eugenii A; Matthews, Paul M

    2010-01-01

    Here we report the first multi-center clinical trial in Alzheimer's disease (AD) using fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) measures of brain glucose metabolism as the primary outcome. We contrasted effects of 12 months treatment with the PPARγ agonist Rosiglitazone XR versus placebo in 80 mild to moderate AD patients. Secondary objectives included testing for reduction in the progression of brain atrophy and improvement in cognition. Active treatment was associated with a sustained but not statistically significant trend from the first month for higher mean values in Kiindex and CMRgluindex, novel quantitative indices related to the combined forward rate constant for [18F]FDG uptake and to the rate of cerebral glucose utilization, respectively. However, neither these nor another analytical approach recently validated using data from the Alzheimer's Disease Neuroimaging Initiative indicated that active treatment decreased the progression of decline in brain glucose metabolism. Rates of brain atrophy were similar between active and placebo groups and measures of cognition also did not suggest clear group differences. Our study demonstrates the feasibility of using [18F]FDG-PET as part of a multi-center therapeutics trial. It suggests that Rosiglitazone is associated with an early increase in whole brain glucose metabolism, but not with any biological or clinical evidence for slowing progression over a 1 year follow up in the symptomatic stages of AD. PMID:20930300

  10. Disseminated Skeletal Muscle and Cardiac Metastasis from Squamous Cell Carcinoma of the Lung Detected with FDG and FLT PET/CT

    PubMed Central

    Jain, Tarun Kumar; Rayamajhi, Sampanna Jung; Basher, Rajender Kumar; Gupta, Dheeraj; Maturu, Venkata Nagarjuna; Mittal, Bhagwant Rai

    2016-01-01

    Lung cancer is one of the leading cancers all over the world. Positron emission tomography (PET) using 18F fluorodeoxyglucose (18F FDG) is useful for staging of the disease and decide the appropriate management. 3’-deoxy-3’-18 F-fluorothymidine (18F FLT) is a tracer being extensively evaluated currently and is said to represent tumor proliferation. Common sites of metastases from lung cancer include adrenal glands, bone, and brain. Muscle metastasis and cardiac metastasis are uncommon findings. We report a case of squamous cell carcinoma of the lung with metastases to multiple skeletal muscles and myocardium detected with both FDG and FLT PET/computed tomography (CT). PMID:27651747

  11. Fluorine F 18 Fluorodopa-Labeled PET Scan in Planning Surgery and Radiation Therapy in Treating Patients With Newly Diagnosed High- or Low-Grade Malignant Glioma

    ClinicalTrials.gov

    2016-10-10

    Adult Anaplastic Astrocytoma; Adult Anaplastic Ependymoma; Adult Anaplastic Oligodendroglioma; Adult Brain Stem Glioma; Adult Diffuse Astrocytoma; Adult Ependymoma; Adult Giant Cell Glioblastoma; Adult Glioblastoma; Adult Gliosarcoma; Adult Mixed Glioma; Adult Myxopapillary Ependymoma; Adult Oligodendroglioma; Adult Pilocytic Astrocytoma; Adult Pineal Gland Astrocytoma; Adult Subependymal Giant Cell Astrocytoma; Adult Subependymoma

  12. Update of the BIPM comparison BIPM.RI(II)-K1.F-18 of activity measurements of the radionuclide 18F to include the 2010 result of the LNE-LNHB (France)

    NASA Astrophysics Data System (ADS)

    Michotte, C.; Ratel, G.; Courte, S.; Cassette, P.; Moune, M.

    2016-01-01

    Since 2001, six national metrology institutes (NMI) have submitted seven samples of known activity of 18F to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.F-18. The values of the activity submitted were between about 1 MBq and 18 MBq. The primary standardization result for the LNE-LNHB, France, replaces their earlier result of 2002 and the key comparison reference value (KCRV) has been recalculated. In the frame of the BIPM.RI(II)-K4.F18 comparison, the NPL updated their result in the KCDB. Consequently there are now five results in the BIPM.RI(II)-K1.F-18 comparison. The degrees of equivalence between each equivalent activity measured in the SIR and the updated KCRV have been calculated and the results are given in the form of a table. A graphical presentation is also given. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  13. [Interest of FDG-PET for lung cancer radiotherapy].

    PubMed

    Thureau, S; Mezzani-Saillard, S; Modzelewski, R; Edet-Sanson, A; Dubray, B; Vera, P

    2011-10-01

    The recent advances in medical imaging have profoundly altered the radiotherapy of non-small cell lung cancers (NSCLC). A meta-analysis has confirmed the superiority of FDG PET-CT over CT for initial staging. FDG PET-CT improves the reproducibility of target volume delineation, especially close to the mediastinum or in the presence of atelectasia. Although not formally validated by a randomized trial, the reduction of the mediastinal target volume, by restricting the irradiation to FDG-avid nodes, is widely accepted. The optimal method of delineation still remains to be defined. The role of FDG PET-CT in monitoring tumor response during radiotherapy is under investigation, potentially opening the way to adapting the treatment modalities to tumor radiation sensitivity. Other tracers, such as F-miso (hypoxia), are also under clinical investigation. To avoid excessive delays, the integration of PET-CT in routine practice requires quick access to the imaging equipment, technical support (fusion and image processing) and multidisciplinary delineation of target volumes. PMID:21880535

  14. Metabolic Changes in the Rodent Brain after Acute Administration of Salvinorin A

    PubMed Central

    Hooker, Jacob M.; Patel, Vinal; Kothari, Shiva; Schiffer, Wynne K.

    2009-01-01

    Purpose Salvinorin A (SA) is a potent and highly selective kappa opioid receptor (KOR) agonist with rapid kinetics and commensurate behavioral effects; however, brain regions associated with these effects have not been determined. Procedures Freely moving adult male rats were given SA intraperitoneally during uptake and trapping of the brain metabolic radiotracer, 18FDG, followed by image acquisition in a dedicated animal PET system. Age-matched control animals received vehicle treatment. Animal behavior during 18FDG uptake was recorded digitally and later analyzed for locomotion. Group differences in regional 18FDG uptake normalized to whole brain were determined using Statistical Parametric Mapping (SPM) and verified by region of interest (ROI) analysis. Results SA treated animals demonstrated significant increases in 18FDG uptake compared to controls in several brain regions associated with the distribution of KOR such as the periaqueductal grey, bed nucleus of the stria terminalis and the cerbellar vermis, as well as in the hypothalamus. Significant bilateral activations were also observed in the auditory, sensory and frontal cortices. Regional decreases in metabolic demand were observed bilaterally in the dorsolateral striatum and hippocampus. Locomotor activity did not differ between SA and vehicle during 18FDG uptake. Conclusions We have provided the first extensive maps of cerebral metabolic activation due to the potent κ-opioid agonist, salvinorin A. A major finding from our small animal PET studies using 18FDG was that neural circuits affected by SA may not be limited to direct activation or inhibition of kappa receptor-expressing cells. Instead, salvinorin A may trigger brain circuits that mediate the effects of the drug on cognition, mood, fear and anxiety, and motor output. PMID:19132449

  15. A study of non-invasive Patlak quantification for whole-body dynamic FDG-PET studies of mice

    PubMed Central

    Zheng, Xiujuan; Wen, Lingfeng; Yu, Shu-Jung; Huang, Sung-Cheng; Feng, David Dagan

    2012-01-01

    Physiological changes in dynamic PET images can be quantitatively estimated by kinetic modeling technique. The process of PET quantification usually requires an input function in the form of a plasma-time activity curve (PTAC), which is generally obtained by invasive arterial blood sampling. However, invasive arterial blood sampling poses many challenges especially for small animal studies, due to the subjects’ limited blood volume and small blood vessels. A simple non-invasive quantification method based on Patlak graphical analysis (PGA) has been recently proposed to use a reference region to derive the relative influx rate for a target region without invasive blood sampling, and evaluated by using the simulation data of human brain FDG-PET studies. In this study, the non-invasive Patlak (nPGA) method was extended to whole-body dynamic small animal FDG-PET studies. The performance of nPGA was systematically investigated by using experimental mouse studies and computer simulations. The mouse studies showed high linearity of relative influx rates between the nPGA and PGA for most pairs of reference and target regions, when an appropriate underlying kinetic model was used. The simulation results demonstrated that the accuracy of the nPGA method was comparable to that of the PGA method, with a higher reliability for most pairs of reference and target regions. The results proved that the nPGA method could provide a non-invasive and indirect way for quantifying the FDG kinetics of tumor in small animal studies. PMID:22956982

  16. Multi-region analysis of longitudinal FDG-PET for the classification of Alzheimer’s disease

    PubMed Central

    Gray, Katherine R.; Wolz, Robin; Heckemann, Rolf A.; Aljabar, Paul; Hammers, Alexander; Rueckert, Daniel

    2012-01-01

    Imaging biomarkers for Alzheimer’s disease are desirable for improved diagnosis and monitoring, as well as drug discovery. Automated image-based classification of individual patients could provide valuable diagnostic support for clinicians, when considered alongside cognitive assessment scores. We investigate the value of combining cross-sectional and longitudinal multi-region FDG-PET information for classification, using clinical and imaging data from the Alzheimer’s Disease Neuroimaging Initiative. Whole-brain segmentations into 83 anatomically defined regions were automatically generated for baseline and 12-month FDG-PET images. Regional signal intensities were extracted at each timepoint, as well as changes in signal intensity over the follow-up period. Features were provided to a support vector machine classifier. By combining 12-month signal intensities and changes over 12 months, we achieve significantly increased classification performance compared with using any of the three feature sets independently. Based on this combined feature set, we report classification accuracies of 88% between patients with Alzheimer’s disease and elderly healthy controls, and 65% between patients with stable mild cognitive impairment and those who subsequently progressed to Alzheimer’s disease. We demonstrate that information extracted from serial FDG-PET through regional analysis can be used to achieve state-of-the-art classification of diagnostic groups in a realistic multi-centre setting. This finding may be usefully applied in the diagnosis of Alzheimer’s disease, predicting disease course in individuals with mild cognitive impairment, and in the selection of participants for clinical trials. PMID:22236449

  17. The Place of FDG PET/CT in Renal Cell Carcinoma: Value and Limitations

    PubMed Central

    Liu, Yiyan

    2016-01-01

    Unlike for most other malignancies, application of FDG PET/CT is limited for renal cell carcinoma (RCC), mainly due to physiological excretion of 18F-fluoro-2-deoxy-2-d-glucose (FDG) from the kidneys, which decreases contrast between renal lesions and normal tissue, and may obscure or mask the lesions of the kidneys. Published clinical observations were discordant regarding the role of FDG PET/CT in diagnosing and staging RCC, and FDG PET/CT is not recommended for this purpose based on current national and international guidelines. However, quantitative FDG PET/CT imaging may facilitate the prediction of the degree of tumor differentiation and allows for prognosis of the disease. FDG PET/CT has potency as an imaging biomarker to provide useful information about patient’s survival. FDG PET/CT can be effectively used for postoperative surveillance and restaging with high sensitivity, specificity, and accuracy, as early diagnosis of recurrent/metastatic disease can drastically affect therapeutic decision and alter outcome of patients. FDG uptake is helpful for differentiating benign or bland emboli from tumor thrombosis in RCC patients. FDG PET/CT also has higher sensitivity and accuracy when compared with bone scan to detect RCC metastasis to the bone. FDG PET/CT can play a strong clinical role in the management of recurrent and metastatic RCC. In monitoring the efficacy of new target therapy such as tyrosine kinase inhibitors (TKIs) treatment for advanced RCC, FDG PET/CT has been increasingly used to assess the therapeutic efficacy, and change in FDG uptake is a strong indicator of biological response to TKI. PMID:27656421

  18. The Place of FDG PET/CT in Renal Cell Carcinoma: Value and Limitations

    PubMed Central

    Liu, Yiyan

    2016-01-01

    Unlike for most other malignancies, application of FDG PET/CT is limited for renal cell carcinoma (RCC), mainly due to physiological excretion of 18F-fluoro-2-deoxy-2-d-glucose (FDG) from the kidneys, which decreases contrast between renal lesions and normal tissue, and may obscure or mask the lesions of the kidneys. Published clinical observations were discordant regarding the role of FDG PET/CT in diagnosing and staging RCC, and FDG PET/CT is not recommended for this purpose based on current national and international guidelines. However, quantitative FDG PET/CT imaging may facilitate the prediction of the degree of tumor differentiation and allows for prognosis of the disease. FDG PET/CT has potency as an imaging biomarker to provide useful information about patient’s survival. FDG PET/CT can be effectively used for postoperative surveillance and restaging with high sensitivity, specificity, and accuracy, as early diagnosis of recurrent/metastatic disease can drastically affect therapeutic decision and alter outcome of patients. FDG uptake is helpful for differentiating benign or bland emboli from tumor thrombosis in RCC patients. FDG PET/CT also has higher sensitivity and accuracy when compared with bone scan to detect RCC metastasis to the bone. FDG PET/CT can play a strong clinical role in the management of recurrent and metastatic RCC. In monitoring the efficacy of new target therapy such as tyrosine kinase inhibitors (TKIs) treatment for advanced RCC, FDG PET/CT has been increasingly used to assess the therapeutic efficacy, and change in FDG uptake is a strong indicator of biological response to TKI.

  19. (18)F-FDG PET/CT imaging in granulomatosis with polyangiitis.

    PubMed

    De Geeter, Frank; Gykiere, Pieterjan

    2016-01-01

    The paper gives an overview of the literature data on uptake of fluorine-18-fluorodeoxyglucose ((18)F-FDG) into the different tissue lesions which may occur in granulomatosis with polyangiitis (formerly called Wegener's syndrome). It discusses the cellular mechanisms of such (18)F-FDG uptake, which provide a basis for its interpretation in the context of (18)F-FDG positron emission tomography (PET) for inflammatory conditions. PMID:26929934

  20. The Place of FDG PET/CT in Renal Cell Carcinoma: Value and Limitations.

    PubMed

    Liu, Yiyan

    2016-01-01

    Unlike for most other malignancies, application of FDG PET/CT is limited for renal cell carcinoma (RCC), mainly due to physiological excretion of 18F-fluoro-2-deoxy-2-d-glucose (FDG) from the kidneys, which decreases contrast between renal lesions and normal tissue, and may obscure or mask the lesions of the kidneys. Published clinical observations were discordant regarding the role of FDG PET/CT in diagnosing and staging RCC, and FDG PET/CT is not recommended for this purpose based on current national and international guidelines. However, quantitative FDG PET/CT imaging may facilitate the prediction of the degree of tumor differentiation and allows for prognosis of the disease. FDG PET/CT has potency as an imaging biomarker to provide useful information about patient's survival. FDG PET/CT can be effectively used for postoperative surveillance and restaging with high sensitivity, specificity, and accuracy, as early diagnosis of recurrent/metastatic disease can drastically affect therapeutic decision and alter outcome of patients. FDG uptake is helpful for differentiating benign or bland emboli from tumor thrombosis in RCC patients. FDG PET/CT also has higher sensitivity and accuracy when compared with bone scan to detect RCC metastasis to the bone. FDG PET/CT can play a strong clinical role in the management of recurrent and metastatic RCC. In monitoring the efficacy of new target therapy such as tyrosine kinase inhibitors (TKIs) treatment for advanced RCC, FDG PET/CT has been increasingly used to assess the therapeutic efficacy, and change in FDG uptake is a strong indicator of biological response to TKI. PMID:27656421

  1. EFFECTS OF ADMINISTRATION ROUTE, DIETARY CONDITION, AND BLOOD GLUCOSE LEVEL ON KINETICS AND UPTAKE OF 18F-FDG IN MICE

    PubMed Central

    Wong, Koon-Pong; Sha, Wei; Zhang, Xiaoli; Huang, Sung-Cheng

    2011-01-01

    The effects of dietary condition and blood glucose level on the kinetics and uptake of 18F-FDG in mice were systematically investigated using intraperitoneal and tail-vein injection. Methods Dynamic PET was performed for 60 min on 23 isoflurane-anesthetized male C57BL/6 mice after intravenous (n = 11) or intraperitoneal (n = 12) injection of 18F-FDG. Five and 6 mice in the intravenous and intraperitoneal groups, respectively, were kept fasting overnight (18 ± 2 h), and the others were fed ad libitum. Serial blood samples were collected from the femoral artery to measure 18F-FDG and glucose concentrations. Image data were reconstructed using filtered backprojection with CT-based attenuation correction. The standardized uptake value (SUV) was estimated from the 45- to 60-min image. The metabolic rate of glucose (MRGlu) and 18F-FDG uptake constant (Ki) were derived by Patlak graphical analysis. Results In the brain, SUV and Ki were significantly higher in fasting mice with intraperitoneal injection, but MRGlu did not differ significantly under different dietary states and administration routes. Cerebral Ki was inversely related to elevated blood glucose levels, irrespective of administration route or dietary state. In myocardium, SUV, Ki, and MRGlu were significantly lower in fasting than in nonfasting mice for both routes of injection. Myocardial SUV and Ki were strongly dependent on the dietary state, and Ki did not correlate with the blood glucose level. Similar results were obtained for skeletal muscle, although the differences were not as pronounced. Conclusions Intraperitoneal injection is a valid alternative route, providing pharmacokinetic data equivalent to data from tail-vein injection for small-animal 18F-FDG PET. Cerebral Ki varies inversely with blood glucose level, but the measured cerebral MRGlu does not correlate with blood glucose level or dietary condition. Conversely, the Ki values of the myocardium and skeletal muscle are strongly dependent on

  2. Protein rich diet suppressed net and unidirectional clearances of 6-[F-18]Fluoro-DOPA to striatum but did not alter relative DOPA decarboxylase activity

    SciTech Connect

    Kuwabara, H.; Cumming, P.; Reutens, D.

    1994-05-01

    We examined the effects of competitors in plasma (i.e., large neutral amino acids, LNAA) on the transport across the blood-brain-barrier and decarboxylation of tracer FDOPA in human striatum. We studied 10 healthy, neurologically normal subjects with the Scanditronix PC 2048-15B PET camera for 2 hours following intravenous injection of FDOPA. The subjects were either fasted overnight (n=6, ages:23-42 years) or received protein rich diet ({approximately}50 g protein) 1 hour before the study (n=4, ages:21-40 years). During the study, we obtained time-courses of radioactivity in arterial plasma and separated FDOPA and O-methyl-fluoro-DOPA with HPLC. We estimated, by means of least-squares optimization, the unidirectional blood-brain D clearance (K{sub 1}{sup D}), relative DOPA decarboxylase activity (k{sub 3}{sup D}), and effective vascular volume (V{sub 0}) in striatum while the partition volume (V{sub e}=K{sub 1}/k2) was set to the individual`s estimates of frontal lobe. The net clearance (K{sup D}) was calculated as K{sub 1}{sup D}k{sub 3}{sup D}/(k{sub 2}{sup D}+k{sub 3}{sup D}).

  3. Normal variations and benign findings in pediatric 18F-FDG-PET/CT.

    PubMed

    Grant, Frederick D

    2014-04-01

    (18)F-FDG PET and PET/CT have a wide variety of indications in children and young adults. Oncologic indications are the most common, but others include neurology, sports medicine, cardiology, and infection imaging. Accurate interpretation of pediatric (18)F-FDG PET and PET/CT requires a technically adequate study and knowledgeable interpretation of the images. A successful pediatric (18)F-FDG PET requires age-appropriate patient preparation and consideration of patient age and developmental stage. Accurate interpretation of the study requires familiarity with normal patterns of physiologic (18)F-FDG uptake in children at all stages of development. PMID:25030282

  4. MRI and FDG PET/CT imaging manifestations of cardiac sarcoidosis.

    PubMed

    Lu, Yang; Sweiss, Nadera J

    2015-12-01

    A 52-year-old man had biopsy-proven sarcoidosis of mediastinal lymph nodes. Cardiac sarcoidosis was confirmed on cardiac MRI with typical imaging features as delayed gadolinium enhancement. Follow-up FDG PET/CT with a 3-day pretest diet modification showed suppression of overall myocardial uptake of FDG but with multifocal abnormal FDG uptake in the myocardium regions corresponding to the previous MRI findings. Additional noncardiac active sarcoidosis involving multiple organ and lymph nodes were also visualized on FDG PET/CT. PMID:26544904

  5. Longitudinal assessment of a transgenic animal model of tauopathy by FDG-PET imaging.

    PubMed

    de Cristóbal, Javier; García-García, Luis; Delgado, Mercedes; Pérez, Mar; Pozo, Miguel A; Medina, Miguel

    2014-01-01

    Abnormal levels and hyperphosphorylation of tau protein have been proposed as the underlying cause of a group of neurodegenerative disorders collectively known as 'tauopathies'. The detrimental consequence is the loss of affinity between this protein and the microtubules, increased production of fibrillary aggregates, and the accumulation of insoluble intracellular neurofibrillary tangles. A similar phenotype can be observed in various preclinical models, which have been generated to study the role of tau protein in neurodegenerative disorders. In this study, we have analyzed the brain metabolic activity in an animal model of tauopathy (tauVLW transgenic mice), which has been previously reported to mimic some of the phenotypic features of these disorders. By using a non-invasive technique, positron emission tomography (PET), a longitudinal non-clinical follow up study was carried out during most of the lifespan of these transgenic mice, from the youth to the senescence stages. The results obtained point out to an aging-dependent decrease in 18F-fluoro-deoxyglucose (FDG) uptake in the cerebral areas analyzed, which was already significant at the adult age, i.e., 11 months, and became much more prominent in the oldest animals (19 months old). This observation correlates well with the histopathological observation of neurodegeneration in brain areas where there is overexpression of tau protein.

  6. Single-scan Bayes estimation of cerebral glucose metabolic rate: comparison with non-Bayes single-scan methods using FDG PET scans in stroke.

    PubMed

    Wilson, P D; Huang, S C; Hawkins, R A

    1988-06-01

    Three single-scan (SS) methods are currently available for estimating the local cerebral metabolic rate of glucose (LCMRG) from F-18 deoxyglucose (FDG) positron emission tomography (PET) scan data: SS(SPH), named for Sokoloff, Phelps, and Huang; SS(B), named for Brooks; and SS(H), named for Hutchins and Holden et al. All three of these SS methods make use of prior information in the form of mean values of rate constants from the normal population. We have developed a Bayes estimation (BE) method that uses prior information in the form of rate constant means, variances, and correlations in both the normal and ischemic tissue populations. The BE method selects, based only on the data, whether the LCMRG estimate should be computed using prior information from normal or ischemic tissue. The ability of BE to make this selection gives it an advantage over the other methods. The BE method can be used as a SS method or can use any number of PET scans. We conducted Monte Carlo studies comparing BE as a SS method with the other SS methods, all using a single scan at 60 min. We found SS(H) to be strongly superior to SS(SPH) and SS(B), and we found BE to be definitely superior to SS(H). PMID:3259241

  7. Clinical, FDG and amyloid PET imaging in posterior cortical atrophy.

    PubMed

    Singh, Tarun D; Josephs, Keith A; Machulda, Mary M; Drubach, Daniel A; Apostolova, Liana G; Lowe, Val J; Whitwell, Jennifer L

    2015-06-01

    The purpose of this study was to identify the clinical, [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and amyloid-PET findings in a large cohort of posterior cortical atrophy (PCA) patients, to examine the neural correlates of the classic features of PCA, and to better understand the features associated with early PCA. We prospectively recruited 25 patients who presented to the Mayo Clinic between March 2013 and August 2014 and met diagnostic criteria for PCA. All patients underwent a standardized set of tests and amyloid imaging with [(11)C] Pittsburg compound B (PiB). Seventeen (68 %) underwent FDG-PET scanning. We divided the cohort at the median disease duration of 4 years in order to assess clinical and FDG-PET correlates of early PCA (n = 13). The most common clinical features were simultanagnosia (92 %), dysgraphia (68 %), poly-mini-myoclonus (64 %) and oculomotor apraxia (56.5 %). On FDG-PET, hypometabolism was observed bilaterally in the lateral and medial parietal and occipital lobes. Simultanagnosia was associated with hypometabolism in the right occipital lobe and posterior cingulum, optic ataxia with hypometabolism in left occipital lobe, and oculomotor apraxia with hypometabolism in the left parietal lobe and posterior cingulate gyrus. All 25 PCA patients were amyloid positive. Simultanagnosia was the only feature present in 85 % of early PCA patients. The syndrome of PCA is associated with posterior hemisphere hypometabolism and with amyloid deposition. Many of the classic features of PCA show associated focal, but not widespread, areas of involvement of these posterior hemispheric regions. Simultanagnosia appears to be the most common and hence sensitive feature of early PCA. PMID:25862483

  8. White Matter Lesion Load Is Associated With Resting State Functional MRI Activity and Amyloid PET but not FDG in Mild Cognitive Impairment and Early Alzheimer's Disease Patients

    PubMed Central

    Zhou, Yongxia; Yu, Fang; Duong, Timothy Q.

    2014-01-01

    Purpose To quantify and investigate the interactions between multimodal MRI/positron emission tomography (PET) imaging metrics in elderly patients with early Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy controls. Materials and Methods Thirteen early AD, 17 MCI patients, and 14 age-matched healthy aging controls from the Alzheimer's Disease Neuroimaging Initiative database were selected based on availability of data. Default mode network (DMN) functional connectivity and fractional amplitude of low frequency fluctuation (fALFF) were obtained for resting state functional MRI (RS-fMRI). White matter lesion load (WMLL) was quantified from MRI T2-weighted FLAIR images. Amyloid deposition with PET [18F]-Florbetapir tracer and metabolism of glucose by means of [18F]-fluoro-2-deoxyglucose (FDG) images were quantified using ratio of standard uptake values (rSUV). Results Whole-brain WMLL and amyloid deposition were significantly higher (P < 0.005) in MCI and AD patients compared with controls. RS-fMRI results showed significantly reduced (corrected P < 0.05) DMN connectiv ity and altered fALFF activity in both MCI and AD groups. FDG uptake results showed hypometabolism in AD and MCI patients compared with controls. Correlations (P < 0.05) were found between WMLL and amyloid load, FDG uptake and amyloid load, as well as between amyloid load (rSUV) and fALFF. Conclusion Our quantitative results of four MRI and PET imaging metrics (fALFF/DMN, WMLL, amyloid, and FDG rSUV values) agree with published values. Signifi-cant correlations between MRI metrics, including WMLL/ functional activity and PET amyloid load suggest the potential of MRI and PET-based biomarkers for early detection of AD. PMID:24382798

  9. Hepatosplenic Candidiasis Detected by (18)F-FDG-PET/CT.

    PubMed

    Albano, Domenico; Bosio, Giovanni; Bertoli, Mattia; Petrilli, Giulia; Bertagna, Francesco

    2016-01-01

    Hepatosplenic candidiasis is a fungal infection, which mostly affects patients with hematologic malignancies such as leukemia. The pathogenesis of this infection is not clear yet, and the liver is the most commonly affected organ. Diagnosis of hepatosplenic candidiasis can be only established via biopsy, since computed tomography (CT) scan, ultrasonography, and magnetic resonance imaging (MRI) yield non-specific results. The role of fluorine-18 fluorodeoxyglucose positron emission tomography /computed tomography ((18)F-FDG PET/CT) in diagnosis of hepatosplenic candidiasis remains undetermined, considering a few evidences in the literature. In this case report, we present the case of a 47-year-old patient, affected by acute myeloid leukemia, which was treated with three cycles of chemotherapy, resulting in the development of neutropenia and fever following the last cycle. The (18)F-FDG PET/CT scan showed some foci of intense FDG uptake in the liver and spleen. The subsequent diagnostic investigations (i.e., abdominal CT scan and biopsy) were suggestive of hepatosplenic candidiasis. The patient was started on antifungal treatment with fluconazole. After one month, the clinical conditions were resolved, and the subsequent abdominal CT scan was negative. PMID:27408899

  10. Temporal Change in Brain Natriuretic Peptide After Radiotherapy for Thoracic Esophageal Cancer

    SciTech Connect

    Jingu, Keiichi Nemoto, Kenji; Kaneta, Tomohiro; Oikawa, Minako; Ogawa, Yoshihiro; Ariga, Hisanori; Takeda, Ken; Sakayauchi, Toru; Fujimoto, Keisuke; Narazaki, Kakutaro; Takai, Yoshihiro; Nakata, Eiko; Fukuda, Hiroshi; Takahashi, Shoki; Yamada, Shogo

    2007-12-01

    Purpose: To investigate the relationships of plasma levels of brain natriuretic peptide (BNP) with abnormal {sup 18}F-fluorodeoxyglucose (FDG) accumulation in the myocardium corresponding to irradiated fields and temporal changes in BNP, which is used as an index of heart remodeling, after radiotherapy for the mediastinum. Materials and Methods: Brain natriuretic peptide concentrations were measured before and after radiotherapy for thoracic esophageal cancer, and the change in BNP concentration after radiotherapy was investigated. Moreover, FDG accumulation in the myocardium was investigated in patients who had undergone FDG positron emission tomography less than 14 days before or after measurement of BNP concentration, and the Mann-Whitney U test was used to detect significant difference between BNP concentrations in patients with and without abnormal FDG accumulation corresponding to the irradiated field. Results: There was significant difference between the levels of BNP in patients without abnormal FDG accumulation in the irradiated myocardium and in patients with abnormal FDG accumulation (p < 0.001). The levels of BNP in the 9-24 months after radiotherapy group and in the >24 months after radiotherapy group were significantly higher than the levels in the before radiotherapy group, immediately after radiotherapy group, 1-2 months after radiotherapy group, and control group. Conclusions: The level of BNP was significantly increased more than 9 months after the start of radiotherapy and was significantly higher in patients who had high FDG accumulation corresponding to the irradiated field. The results of this study indicate that BNP concentration might be an early indicator of radiation-induced myocardial damage.

  11. Differences in Brain Metabolic Impairment between Chronic Mild/Moderate TBI Patients with and without Visible Brain Lesions Based on MRI

    PubMed Central

    Asano, Yoshitaka; Ikegame, Yuka

    2016-01-01

    Introduction. Many patients with mild/moderate traumatic brain injury (m/mTBI) in the chronic stage suffer from executive brain function impairment. Analyzing brain metabolism is important for elucidating the pathological mechanisms associated with their symptoms. This study aimed to determine the differences in brain glucose metabolism between m/mTBI patients with and without visible traumatic brain lesions based on MRI. Methods. Ninety patients with chronic m/mTBI due to traffic accidents were enrolled and divided into two groups based on their MRI findings. Group A comprised 50 patients with visible lesions. Group B comprised 40 patients without visible lesions. Patients underwent FDG-PET scans following cognitive tests. FDG-PET images were analyzed using voxel-by-voxel univariate statistical tests. Results. There were no significant differences in the cognitive tests between Group A and Group B. Based on FDG-PET findings, brain metabolism significantly decreased in the orbital gyrus, cingulate gyrus, and medial thalamus but increased in the parietal and occipital convexity in Group A compared with that in the control. Compared with the control, patients in Group B exhibited no significant changes. Conclusions. These results suggest that different pathological mechanisms may underlie cognitive impairment in m/mTBI patients with and without organic brain damage. PMID:27529067

  12. Differences in Brain Metabolic Impairment between Chronic Mild/Moderate TBI Patients with and without Visible Brain Lesions Based on MRI.

    PubMed

    Ito, Keiichi; Asano, Yoshitaka; Ikegame, Yuka; Shinoda, Jun

    2016-01-01

    Introduction. Many patients with mild/moderate traumatic brain injury (m/mTBI) in the chronic stage suffer from executive brain function impairment. Analyzing brain metabolism is important for elucidating the pathological mechanisms associated with their symptoms. This study aimed to determine the differences in brain glucose metabolism between m/mTBI patients with and without visible traumatic brain lesions based on MRI. Methods. Ninety patients with chronic m/mTBI due to traffic accidents were enrolled and divided into two groups based on their MRI findings. Group A comprised 50 patients with visible lesions. Group B comprised 40 patients without visible lesions. Patients underwent FDG-PET scans following cognitive tests. FDG-PET images were analyzed using voxel-by-voxel univariate statistical tests. Results. There were no significant differences in the cognitive tests between Group A and Group B. Based on FDG-PET findings, brain metabolism significantly decreased in the orbital gyrus, cingulate gyrus, and medial thalamus but increased in the parietal and occipital convexity in Group A compared with that in the control. Compared with the control, patients in Group B exhibited no significant changes. Conclusions. These results suggest that different pathological mechanisms may underlie cognitive impairment in m/mTBI patients with and without organic brain damage. PMID:27529067

  13. Potential Pitfall in the Assessment of Lung Cancer with FDG-PET/CT: Talc Pleurodesis Causes Intrathoracic Nodal FDG Avidity

    PubMed Central

    Carter, Brett W.; Muse, Victorine; Digumarthy, Subba; Shepard, Jo-Anne; Sharma, Amita

    2013-01-01

    Objective. Talc pleurodesis is a common procedure performed to treat complications related to lung cancer. The purpose of our study was to characterize any thoracic nodal findings on FDG PET/CT associated with prior talc pleurodesis. Materials and Methods. The electronic medical record identified 44 patients who underwent PET/CT between January 2006 and December 2010 and had a history of talc pleurodesis. For each exam, we evaluated the distribution pattern, size, and attenuation of intrathoracic lymph nodes and the associated standardized uptake value. Results. High-attenuation intrathoracic lymph nodes were noted in 11 patients (25%), and all had corresponding increased FDG uptake (range 2–9 mm). Involved nodal groups were anterior peridiaphragmatic (100%), paracardiac (45%), internal mammary (25%), and peri-IVC (18%) nodal stations. Seven of the 11 patients (63%) had involvement of multiple lymph nodal groups. Mean longitudinal PET/CT and standalone CT followups of 15 ± 11 months showed persistence of both high-attenuation and increased uptake at these sites, without increase in nodal size suggesting metastatic disease involvement. Conclusions. FDG avid, high-attenuation lymph nodes along the lymphatic drainage pathway for parietal pleura are a relatively common finding following talc pleurodesis and should not be mistaken for nodal metastases during the evaluation of patients with history of lung cancer. PMID:26316941

  14. Causes of (18)F-FDG uptake on white adipose tissue.

    PubMed

    Hwang, Doh Yu; Lee, Jeong Won; Lee, Sang Mi; Kim, Soon

    2016-01-01

    White adipose tissue usually shows negligible fluorine-18-fluorodeoxyglucose ((18)F-FDG) uptake. In certain clinical conditions this (18)F-FDG uptake has been reported to be increased like in HIV patients under treatment, in exogenous Cushing's syndrome, in cases related to premedication and other cases. PMID:26929935

  15. Parallel ICA of FDG-PET and PiB-PET in three conditions with underlying Alzheimer's pathology.

    PubMed

    Laforce, Robert; Tosun, Duygu; Ghosh, Pia; Lehmann, Manja; Madison, Cindee M; Weiner, Michael W; Miller, Bruce L; Jagust, William J; Rabinovici, Gil D

    2014-01-01

    AD-visuospatial (bilateral occipito-parieto-temporal [AUC 0.85, p = 0.009] and right posterior cingulate cortex [PCC]/precuneus and right lateral parietal [AUC 0.69, p = 0.045]). The AD-memory associated component included predominantly bilateral inferior frontal, cuneus and inferior temporal, and right inferior parietal hypometabolism but did not reach significance (AUC 0.65, p = 0.062). None of the PiB components correlated with clinical group. Joint analysis of PiB and FDG with pICA revealed a correlated component pair, in which increased frontal and decreased PCC/precuneus PiB correlated with decreased FDG in the frontal, occipital and temporal regions (partial r = 0.75, p < 0.0001). Using multivariate data analysis, this study reinforced the notion that clinical phenotype in AD is tightly linked to patterns of glucose hypometabolism but not amyloid deposition. These findings are strikingly similar to those of univariate paradigms and provide additional support in favor of specific involvement of the language network, higher-order visual network, and default mode network in clinical variants of AD. The inverse relationship between Aβ deposition and glucose metabolism in partially overlapping brain regions suggests that Aβ may exert both local and remote effects on brain metabolism. Applying multivariate approaches such as pICA to multimodal imaging data is a promising approach for unraveling the complex relationships between different elements of AD pathophysiology.

  16. S-values calculated from a tomographic head/brain model for brain imaging

    NASA Astrophysics Data System (ADS)

    Chao, Tsi-chian; Xu, X. George

    2004-11-01

    A tomographic head/brain model was developed from the Visible Human images and used to calculate S-values for brain imaging procedures. This model contains 15 segmented sub-regions including caudate nucleus, cerebellum, cerebral cortex, cerebral white matter, corpus callosum, eyes, lateral ventricles, lenses, lentiform nucleus, optic chiasma, optic nerve, pons and middle cerebellar peduncle, skull CSF, thalamus and thyroid. S-values for C-11, O-15, F-18, Tc-99m and I-123 have been calculated using this model and a Monte Carlo code, EGS4. Comparison of the calculated S-values with those calculated from the MIRD (1999) stylized head/brain model shows significant differences. In many cases, the stylized head/brain model resulted in smaller S-values (as much as 88%), suggesting that the doses to a specific patient similar to the Visible Man could have been underestimated using the existing clinical dosimetry.

  17. Spectrum of the Breast Lesions With Increased 18F-FDG Uptake on PET/CT

    PubMed Central

    Dong, Aisheng; Wang, Yang; Lu, Jianping; Zuo, Changjing

    2016-01-01

    Abstract Interpretation of 18F-FDG PET/CT studies in breast is challenging owing to nonspecific FDG uptake in various benign and malignant conditions. Benign conditions include breast changes in pregnancy and lactation, gynecomastia, mastitis, fat necrosis, fibroadenoma, intraductal papilloma, and atypical ductal hyperplasia. Among malignancies, invasive ductal carcinoma and invasive lobular carcinoma are common histological types of breast carcinoma. Rarely, other unusual histological types of breast carcinomas (eg, intraductal papillary carcinoma, invasive micropapillary carcinoma, medullary carcinoma, mucinous carcinoma, and metaplastic carcinoma), lymphoma, and metastasis can be the causes. Knowledge of a wide spectrum of hypermetabolic breast lesions on FDG PET/CT is essential in accurate reading of FDG PET/CT. The purpose of this atlas article is to demonstrate features of various breast lesions encountered at our institution, both benign and malignant, which can result in hypermetabolism on FDG PET/CT imaging. PMID:26975010

  18. Spectrum of the Breast Lesions With Increased 18F-FDG Uptake on PET/CT.

    PubMed

    Dong, Aisheng; Wang, Yang; Lu, Jianping; Zuo, Changjing

    2016-07-01

    Interpretation of F-FDG PET/CT studies in breast is challenging owing to nonspecific FDG uptake in various benign and malignant conditions. Benign conditions include breast changes in pregnancy and lactation, gynecomastia, mastitis, fat necrosis, fibroadenoma, intraductal papilloma, and atypical ductal hyperplasia. Among malignancies, invasive ductal carcinoma and invasive lobular carcinoma are common histological types of breast carcinoma. Rarely, other unusual histological types of breast carcinomas (eg, intraductal papillary carcinoma, invasive micropapillary carcinoma, medullary carcinoma, mucinous carcinoma, and metaplastic carcinoma), lymphoma, and metastasis can be the causes. Knowledge of a wide spectrum of hypermetabolic breast lesions on FDG PET/CT is essential in accurate reading of FDG PET/CT. The purpose of this atlas article is to demonstrate features of various breast lesions encountered at our institution, both benign and malignant, which can result in hypermetabolism on FDG PET/CT imaging. PMID:26975010

  19. A novel description of FDG excretion in the renal system: application to metformin-treated models

    NASA Astrophysics Data System (ADS)

    Garbarino, S.; Caviglia, G.; Sambuceti, G.; Benvenuto, F.; Piana, M.

    2014-05-01

    This paper introduces a novel compartmental model describing the excretion of 18F-fluoro-deoxyglucose (FDG) in the renal system and a numerical method based on the maximum likelihood for its reduction. This approach accounts for variations in FDG concentration due to water re-absorption in renal tubules and the increase of the bladder’s volume during the FDG excretion process. From the computational viewpoint, the reconstruction of the tracer kinetic parameters is obtained by solving the maximum likelihood problem iteratively, using a non-stationary, steepest descent approach that explicitly accounts for the Poisson nature of nuclear medicine data. The reliability of the method is validated against two sets of synthetic data realized according to realistic conditions. Finally we applied this model to describe FDG excretion in the case of animal models treated with metformin. In particular we show that our approach allows the quantitative estimation of the reduction of FDG de-phosphorylation induced by metformin.

  20. ¹⁸F-FDG PET/CT for Staging and Restaging of Breast Cancer.

    PubMed

    Groheux, David; Cochet, Alexandre; Humbert, Olivier; Alberini, Jean-Louis; Hindié, Elif; Mankoff, David

    2016-02-01

    Many studies have pointed out the role of (18)F-FDG PET/CT (or (18)F-FDG PET) in patients with clinical stage III or II breast cancer. (18)F-FDG PET/CT might advantageously replace other staging procedures, such as bone scanning and possibly contrast-enhanced CT of the thorax or abdomen-pelvis. We discuss the findings, locoregional or distant, that can be expected in different categories of breast cancer and their impact on prognosis and management. We also discuss the role of (18)F-FDG PET/CT in restaging and how (18)F-FDG PET/CT compares with conventional techniques in restaging for patients with suspected disease recurrence. We conclude with some recommendations for clinical practice and future research. PMID:26834096

  1. Accuracy of FDG-PET to diagnose lung cancer in a region of endemic granulomatous disease

    PubMed Central

    Deppen, Stephen; Putnam, Joe B.; Andrade, Gabriela; Speroff, Theodore; Nesbitt, Jonathan C.; Lambright, Eric S.; Massion, Pierre P.; Walker, Ron; Grogan, Eric L.

    2011-01-01

    Background 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) is used to evaluate suspicious pulmonary lesions due to its diagnostic accuracy. The southeastern United States has a high prevalence of infectious granulomatous lung disease, and the accuracy of FDGPET may be reduced in this population. We examined the diagnostic accuracy of FDG-PET in patients with known or suspected NSCLC treated at our institution. Methods 279 patients identified through our prospective database, underwent an operation for known or suspected lung cancer. Preoperative FDG-PET in 211 eligible patients was defined by standardized uptake value, SUV > 2.5 or by description (“moderate” or “intense”) as avid. Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and decision diagrams were calculated for FDG-PET in all patients and in patients with indeterminate nodules. Results In all eligible patients (n=211), sensitivity and specificity of FDG-PET were 92% and 40%. Positive and negative predictive values were 86% and 55%. Overall FDG-PET accuracy to diagnose lung cancer was 81%. Preoperative positive likelihood ratio for FDG-PET diagnosis of lung cancer in this population was 1.5 compared to previously published values of 7.1. In 113 indeterminate lesions, 65% had lung cancer and the sensitivity and specificity were 89% and 40% respectively. 24 benign nodules (60%) had false positive FDG-PET scans. 22 of 43 benign nodules (51%) were granulomas. Conclusions In a region with endemic granulomatous diseases, the specificity of FDG-PET for diagnosis of lung cancer was 40%. Clinical decisions and future clinical predictive models for lung cancer must accommodate regional variation of FDG-PET scan results. PMID:21592456

  2. Sparse brain network using penalized linear regression

    NASA Astrophysics Data System (ADS)

    Lee, Hyekyoung; Lee, Dong Soo; Kang, Hyejin; Kim, Boong-Nyun; Chung, Moo K.

    2011-03-01

    Sparse partial correlation is a useful connectivity measure for brain networks when it is difficult to compute the exact partial correlation in the small-n large-p setting. In this paper, we formulate the problem of estimating partial correlation as a sparse linear regression with a l1-norm penalty. The method is applied to brain network consisting of parcellated regions of interest (ROIs), which are obtained from FDG-PET images of the autism spectrum disorder (ASD) children and the pediatric control (PedCon) subjects. To validate the results, we check their reproducibilities of the obtained brain networks by the leave-one-out cross validation and compare the clustered structures derived from the brain networks of ASD and PedCon.

  3. Gliomatosis cerebri mimicking encephalitis evaluated using fluorine-18 fluorodeoxyglucose: Positron emission tomography/computed tomography

    PubMed Central

    Kamaleshwaran, Koramadai Karuppusamy; Krishnan, Vijayan; Mohanan, Vyshakh; Shibu, Deepu; Shinto, Ajit Sugunan

    2015-01-01

    Gliomatosis cerebri (GC) is a rare condition in which an infiltrative glial neoplasm spreads through the brain with preservation of the underlying structure. F-18 fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has an important role in demonstrating the appropriate metabolism and differentiating pathologies mimicking GC on CT and magnetic resonance imaging. We describe imaging findings of FDG PET/CT in GC in a 9-year-old male child mimicking encephalitis. PMID:25589818

  4. Gliomatosis cerebri mimicking encephalitis evaluated using fluorine-18 fluorodeoxyglucose: Positron emission tomography/computed tomography.

    PubMed

    Kamaleshwaran, Koramadai Karuppusamy; Krishnan, Vijayan; Mohanan, Vyshakh; Shibu, Deepu; Shinto, Ajit Sugunan

    2015-01-01

    Gliomatosis cerebri (GC) is a rare condition in which an infiltrative glial neoplasm spreads through the brain with preservation of the underlying structure. F-18 fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) has an important role in demonstrating the appropriate metabolism and differentiating pathologies mimicking GC on CT and magnetic resonance imaging. We describe imaging findings of FDG PET/CT in GC in a 9-year-old male child mimicking encephalitis.

  5. Heavy perfluorocarbons in the global atmosphere: Atmospheric histories and top-down global emission estimates for C4F10, C5F12, C6F14, C7F16 and C8F18

    NASA Astrophysics Data System (ADS)

    Ivy, D. J.; Arnold, T.; Rigby, M. L.; Baasandorj, M.; Muhle, J.; Harth, C.; Salameh, P.; Steele, P.; Leist, M.; Krummel, P. B.; Burkholder, J. B.; Fraser, P.; Weiss, R. F.; Prinn, R. G.

    2011-12-01

    The high molecular weight perfluorocarbons (PFCs) - perfluorobutane (C4F10), perfluoropentane (C5F12), perfluorohexane (C6F14), perfluoroheptane (C7F16) and perfluorooctane (C8F18) - are potent greenhouse gases with global warming potentials of ~ 9000 for a 100 year time horizon [Forster et al., 2007]. Currently, the heavy PFCs are regulated under the Kyoto Protocol of the United Nations Framework Convention on Climate Change (UNFCCC). However, no atmospheric observations or top-down emission estimates for these gases have been published. In this study, atmospheric histories of the heavy PFCs were determined through new measurements of the Cape Grim Air Archive and a collection of Northern Hemispheric archive flasks using the Advanced Global Atmospheric Gases Experiment (AGAGE) cryogenic preconcentration gas chromatography-mass spectrometry system "Medusa" [Miller et al., 2008]. Furthermore, global top-down emissions were estimated from 1973-2010 based on the atmospheric histories using an inverse method and the 3-D chemical transport model, Model of OZone and Related Tracers (MOZARTv4.5) [Emmons et al., 2009]. Comparison of the top-down emission estimates with bottom-up estimates from the Emissions Database for Global Atmospheric Research (EDGARv4.1) shows EDGARv4.1 emission estimates are underestimated by orders of magnitude for C4F10 and C5F12 [European Commission, 2009]. The bottom-up estimates from EDGARv4.1 are comparable to the top-down estimates for C6F14 and C7F16; no bottom-up emission estimates are available for C8F18. Generally, UNFCCC reported inventories by countries that have ratified the Kyoto Protocol are 5 to 10 times lower than the top-down emission estimates for C4F10, C5F12 and C6F14 (C7F16 and C8F18 are not reported to the UNFCCC). The atmospheric histories and top-down emission estimates presented are the most accurate and comprehensive compiled so far for the high molecular weight PFCs. Furthermore, this study illustrates the importance of

  6. Human radiation dosimetry of 6-[{sup 18}F]FDG predicted from preclinical studies

    SciTech Connect

    Muzic, Raymond F.; Chandramouli, Visvanathan; Hatami, Ahmad; Huang, Hsuan-Ming; Wu, Chunying; Ismail-Beigi, Faramarz

    2014-03-15

    Purpose: The authors are developing 6-[{sup 18}F]fluoro-6-deoxy-D-glucose (6-[{sup 18}F]FDG) as an in vivo tracer of glucose transport. While 6-[{sup 18}F]FDG has the same radionuclide half-life as 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (2-[{sup 18}F]FDG) which is ubiquitously used for PET imaging, 6-[{sup 18}F]FDG has special biologic properties and different biodistributions that make it preferable to 2-[{sup 18}F]FDG for assessing glucose transport. In preparation for 6-[{sup 18}F]FDG use in human PET scanning, the authors would like to determine the amount of 6-[{sup 18}F]FDG to inject while maintaining radiation doses in a safe range. Methods: Rats were injected with 6-[{sup 18}F]FDG, euthanized at specified times, and tissues were collected and assayed for activity content. For each tissue sample, the percent of injected dose per gram was calculated and extrapolated to that for humans in order to construct predicted time-courses. Residence times were calculated as areas under the curves and were used as inputs to OLINDA/EXM in order to calculate the radiation doses. Results: Unlike with 2-[{sup 18}F]FDG for which the urinary bladder wall receives the highest absorbed dose due to urinary excretion, with 6-[{sup 18}F]FDG there is little urinary excretion and osteogenic cells and the liver are predicted to receive the highest absorbed doses: 0.027 mGy/MBq (0.100 rad/mCi) and 0.018 mGy/MBq (0.066 rad/mCi), respectively. Also, the effective dose from 6-[{sup 18}F]FDG, i.e., 0.013 mSv/MBq (0.046 rem/mCi), is predicted to be approximately 30% lower than that from 2-[{sup 18}F]FDG. Conclusions: 6-[{sup 18}F]FDG will be safe for use in the PET scanning of humans.

  7. Heterogeneous 18F-FDG uptake in recurrent respiratory papillomatosis.

    PubMed

    Yu, John-Paul J; Barajas, Ramon F; Olorunsola, Dare; Sugrue, Leo P; Hernandez-Pampaloni, Miguel

    2013-05-01

    Recurrent respiratory papillomatosis (RRP) describes an infection of the upper aerodigestive tract by the human papilloma virus most commonly affecting the larynx with rare lung involvement in 1%-2% of affected patients. We describe an unusual case of a 28-year-old male patient with a longstanding history of RRP where a whole-body PET/CT obtained for disease staging revealed multiple cavitary pulmonary nodules in addition to the more typical tracheobronchial papillomas. In the case described herein, we report heterogeneous uptake of 18F-FDG among these RRP lesions, suggesting significant unexpected variability in the underlying metabolic behavior of these lesions. PMID:23486321

  8. Electron-tracking Compton gamma-ray camera for small animal and phantom imaging

    NASA Astrophysics Data System (ADS)

    Kabuki, Shigeto; Kimura, Hiroyuki; Amano, Hiroo; Nakamoto, Yuji; Kubo, Hidetoshi; Miuchi, Kentaro; Kurosawa, Shunsuke; Takahashi, Michiaki; Kawashima, Hidekazu; Ueda, Masashi; Okada, Tomohisa; Kubo, Atsushi; Kunieda, Etuso; Nakahara, Tadaki; Kohara, Ryota; Miyazaki, Osamu; Nakazawa, Tetsuo; Shirahata, Takashi; Yamamoto, Etsuji; Ogawa, Koichi; Togashi, Kaori; Saji, Hideo; Tanimori, Toru

    2010-11-01

    We have developed an electron-tracking Compton camera (ETCC) for medical use. Our ETCC has a wide energy dynamic range (200-1300 keV) and wide field of view (3 sr), and thus has potential for advanced medical use. To evaluate the ETCC, we imaged the head (brain) and bladder of mice that had been administered with F-18-FDG. We also imaged the head and thyroid gland of mice using double tracers of F-18-FDG and I-131 ions.

  9. Enhanced regional brain metabolic responses to benzodiazepines in cocaine abusers

    SciTech Connect

    Volkow, N.D.; Wang, G.J.; Fowler, J.S.

    1997-05-01

    While dopamine (DA) appears to be crucial for cocaine reinforcement, its involvement in cocaine addiction is much less clear. Using PET we have shown persistent reductions in striatal DA D2 receptors (which arc predominantly located on GABA cells) in cocaine abusers. This finding coupled to GABA`s role as an effector for DA led us to investigate if there were GABAergic abnormalities in cocaine abusers. In this study we measured regional brain metabolic responses to lorazepam, to indirectly assess GABA function (benzodiazepines facilitate GABAergic neurotransmission). Methods: The experimental subjects consisted of 12 active cocaine abusers and 32 age matched controls. Each subject underwent two PET FDG scans obtained within 1 week of each other. The first FDG scan was obtained after administration of placebo (3 cc of saline solution) given 40-50 minutes prior to FDG; and the second after administration of lorazepam (30 {mu}g/kg) given 40-50 minutes prior to FDG. The subjects were blind to the drugs received. Results: Lorazepam-induced sleepiness was significantly greater in abusers than in controls (p<0.001). Lorazepam-induced decreases in brain glucose metabolism were significantly larger in cocaine abusers than in controls. Whereas in controls whole brain metabolism decreased 13{+-}7 %, in cocaine abusers it decreased 21{+-}13 % (p < 0.05). Lorazepam-induced decrements in regional metabolism were significantly larger in striatum (p < 0.0 1), thalamus (p < 0.01) and cerebellum (p < 0.005) of cocaine abusers than of controls (ANOVA diagnosis by condition (placebo versus lorazepam) interaction effect). The only brain region for which the absolute metabolic changes-induced by lorazepam in cocaine abusers were equivalent to those in controls was the orbitofrontal cortex. These results document an accentuated sensitivity to benzodiazepines in cocaine abusers which is compatible with disrupted GABAergic function in these patients.

  10. Gapless spin liquid ground state in the S = 1/2 vanadium oxyfluoride kagome antiferromagnet [NH4]2[C7H14N][V7O6F18].

    PubMed

    Clark, L; Orain, J C; Bert, F; De Vries, M A; Aidoudi, F H; Morris, R E; Lightfoot, P; Lord, J S; Telling, M T F; Bonville, P; Attfield, J P; Mendels, P; Harrison, A

    2013-05-17

    The vanadium oxyfluoride [NH(4)](2)[C(7)H(14)N][V(7)O(6)F(18)] (DQVOF) is a geometrically frustrated magnetic bilayer material. The structure consists of S = 1/2 kagome planes of V(4+) d(1) ions with S = 1 V(3+) d(2) ions located between the kagome layers. Muon spin relaxation measurements demonstrate the absence of spin freezing down to 40 mK despite an energy scale of 60 K for antiferromagnetic exchange interactions. From magnetization and heat capacity measurements we conclude that the S = 1 spins of the interplane V(3+) ions are weakly coupled to the kagome layers, such that DQVOF can be viewed as an experimental model for S = 1/2 kagome physics, and that it displays a gapless spin liquid ground state.

  11. Maternal age affects brain metabolism in adult children of mothers affected by Alzheimer’s disease

    PubMed Central

    Mosconi, Lisa; Tsui, Wai; Murray, John; McHugh, Pauline; Li, Yi; Williams, Schantel; Pirraglia, Elizabeth; Glodzik, Lidia; De Santi, Susan; Vallabhajosula, Shankar; de Leon, Mony J.

    2011-01-01

    Cognitively normal (NL) individuals with a maternal history of late-onset Alzheimer’s disease (MH) show reduced brain glucose metabolism on FDG-PET as compared to those with a paternal history (PH) and those with negative family history (NH) of Alzheimer’s disease (AD). This FDG-PET study investigates whether metabolic deficits in NL MH are associated with advancing maternal age at birth. Ninety-six NL individuals with FDG-PET were examined, including 36 MH, 24 PH, and 36 NH. Regional-to-whole brain gray matter standardized FDG uptake value ratios were examined for associations with parental age across groups using automated regions-of-interest and statistical parametric mapping. Groups were comparable for clinical and neuropsychological measures. Brain metabolism in AD-vulnerable regions was lower in MH compared to NH and PH, and negatively correlated with maternal age at birth only in MH. There were no associations between paternal age and metabolism in any group. Evidence for a maternally inherited, maternal age-related mechanism provides further insight on risk factors and genetic transmission in late-onset AD. PMID:21514691

  12. Maternal age affects brain metabolism in adult children of mothers affected by Alzheimer's disease.

    PubMed

    Mosconi, Lisa; Tsui, Wai; Murray, John; McHugh, Pauline; Li, Yi; Williams, Schantel; Pirraglia, Elizabeth; Glodzik, Lidia; De Santi, Susan; Vallabhajosula, Shankar; de Leon, Mony J

    2012-03-01

    Cognitively normal (NL) individuals with a maternal history of late-onset Alzheimer's disease (MH) show reduced brain glucose metabolism on FDG-PET as compared to those with a paternal history (PH) and those with negative family history (NH) of Alzheimer's disease (AD). This FDG-PET study investigates whether metabolic deficits in NL MH are associated with advancing maternal age at birth. Ninety-six NL individuals with FDG-PET were examined, including 36 MH, 24 PH, and 36 NH. Regional-to-whole brain gray matter standardized FDG uptake value ratios were examined for associations with parental age across groups using automated regions-of-interest and statistical parametric mapping. Groups were comparable for clinical and neuropsychological measures. Brain metabolism in AD-vulnerable regions was lower in MH compared to NH and PH, and negatively correlated with maternal age at birth only in MH. There were no associations between paternal age and metabolism in any group. Evidence for a maternally inherited, maternal age-related mechanism provides further insight on risk factors and genetic transmission in late-onset AD.

  13. Incidental prostate ¹⁸F-FDG uptake without calcification indicates the possibility of prostate cancer.

    PubMed

    Seino, Hiroko; Ono, Shuichi; Miura, Hiroyuki; Morohashi, Satoko; Wu, Yunyan; Tsushima, Fumiyasu; Takai, Yoshihiro; Kijima, Hiroshi

    2014-04-01

    Incidental 18F-fluorodeoxyglucose (18F-FDG) uptake in the prostate is often experienced in clinical practice; however, it is difficult to determine whether incidental uptake is indicative of a malignancy or benign state based on the maximum standardized uptake value (SUVmax). In the present study, we investigated the clinical significance of incidental prostate uptake by 18F-FDG positron emission tomography (PET)/CT, and examined the differences between malignant and benign uptake from a clinicopathological viewpoint. We reviewed 3,236 male subjects who underwent 18F-FDG PET/CT scans at Hirosaki University Hospital (Japan) from 2008 to 2012 in order to identify cases of incidental prostate FDG uptake. The final diagnosis was made by serum prostate-specific antigen (PSA) levels, biopsy, imaging studies and clinical follow-up with PET findings. Incidental FDG uptake of the prostate was observed in 53 cases (2%). Four cases were excluded due to insufficient clinical data, and 49 cases were included in the present study. Of the 49 cases, 8 (16%) had prostate cancer, while 41 (84%) were benign. All 8 malignant cases had high uptake areas, e.g. in the prostate peripheral zone, where there was no coexistence of calcification or FDG uptake. Of the 41 benign cases, 19 had high uptake in the inner zone, 17 in the peripheral zone, and 5 in both the inner and peripheral zones. Of the 41 cases, 18 (44%) showed FDG uptake coexisting with prostatic calcification. Incidental prostate 18F-FDG uptake infrequently signifies prostate cancer; however, FDG uptake not coexisting with calcification indicates the possibility of prostate cancer and should be included in the differential diagnosis for performing other clinical examinations.

  14. Cerebral necrosis after radiotherapy and/or intraarterial chemotherapy for brain tumors: PET and neuropathologic studies

    SciTech Connect

    Di Chiro, G.; Oldfield, E.; Wright, D.C.; De Michele, D.; Katz, D.A.; Patronas, N.J.; Doppman, J.L.; Larson, S.M.; Ito, M.; Kufta, C.V.

    1988-01-01

    Cerebral necrosis after radiotherapy for brain tumors is being recognized as a problem more common than previously estimated. Distinction between this iatrogenic complication and tumor recurrence cannot be made by either CT or MR imaging. By using positron emission tomography (PET) with /sup 18/F-deoxyglucose (FDG) we were able to reach a diagnosis of radiation necrosis, later verified, in 10 of 95 patients referred for the purpose of differentiating tumor recurrence from necrosis. The critical PET-FDG feature was focal hypometabolism in the area of necrosis, which contrasted with the hypermetabolism associated with the residual/recurrent tumor. In addition, four cases of cerebral necrosis after supraophthalmic, intraarterial chemotherapy (BCNU) were studied with the PET-FDG method. The area of chemotherapy damage was also characterized by marked hypometabolism. Histology revealed both similarities and differences between radio- and chemonecrosis.

  15. Role of FDG PET/CT in Baastrup's disease

    PubMed Central

    Subramanyam, Padma; Palaniswamy, Shanmuga Sundaram

    2016-01-01

    Baastrup's disease is a benign condition, which presents as chronic low back pain. It is also known as “kissing spine syndrome” and refers to close approximation of adjacent spinous processes producing inflammation and back pain. This condition is often misdiagnosed, resulting in incorrect treatment and persistence of symptoms. Diagnosis of Baastrup's disease is verified with clinical examination and imaging studies. Conventionally, clinicians resort to magnetic resonance imaging (MRI) of spine rather than X-ray or computed tomography (CT) in the evaluation of back pain. MRI can additionally identify flattening, sclerosis, enlargement, cystic lesions, and bone edema at the articulating surfaces of the two affected spinous processes. Studies have reported that 18Fluorine fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) can detect a bursitis or an inflammation as a form of stress reaction despite a negative MRI and 99mTc Methylene diphosphonate (MDP) bone scan. PET/CT is usually not a recommended investigation for this condition. However, this case report highlights the benefit of FDG-PET/CT in identifying the site of inflammatory pathology. It is also known to identify the exact site of inflammation where steroid or local anesthetic injection can be administered to alleviate pain, especially in patients with multilevel vertebral involvement. PMID:27385901

  16. Utilization of CT images for the quantification of FDG uptake

    NASA Astrophysics Data System (ADS)

    Karidioula, I.; De Freitas, D.; Cachin, F.; Geissler, B.; Jullien, Ph.; Maublant, J.

    2006-12-01

    The aim of this study was to evaluate an automatic method based on a computed tomography (CT) derived region of interest (ROI) to quantify the mean standardized uptake value (SUVm) of 18F-fluoro-deoxy-glucose (FDG) in pulmonary lesions detected by positron emission tomography (PET). A total of 164 pairs of slices were selected in a series of PET/CT studies performed in 26 patients presenting lung tumours of various forms and complexities. On each matched CT slice, a ROI was obtained by growth-region segmentation starting from a pixel contained in the tumour. The obtained ROI was then applied to the PET image to calculate SUVm. Results were compared with the conventional manual method using a geometric ROI positioned directly on the PET lesion. The automatic delineation of the tumour from the CT image was successful in 136 sections (83%). The SUVm calculated by the manual and automatic method were respectively (mean±standard deviation) 5.05±2.39 and 6.70±3.18 ( p<0.05). The ROI size (in number of pixels) was respectively 28±23 and 21±17 ( p<0.05). The variability of the automatic method was 0% versus 20% for the manual method. SUV of FDG in PET/CT can be calculated with an excellent reproducibility by using the CT-derived limits of the lesion.

  17. Pelvis: normal variants and benign findings in FDG-PET/CT imaging.

    PubMed

    Kohan, Andres; Avril, Norbert E

    2014-04-01

    With the widespread use of whole-body fluorodeoxyglucose (FDG)-PET/computed tomography as a diagnostic tool in patients with cancer, incidental findings are of increasing importance. This is particularly true within the pelvis, where several benign findings might present with increased FDG uptake. In addition, physiologic excretion of radiotracer by way of the urinary tract can complicate image analysis. This article reviews potential incidental benign findings in the pelvis that one should be aware of when interpreting FDG-PET/computed tomography scans.

  18. 18F-FDG PET/CT Demonstrating Malignant Degeneration of a Uterine Fibroid.

    PubMed

    Sharma, Punit

    2016-10-01

    Whereas benign leiomyoma of the uterus (fibroid) is very common, malignant degeneration of such fibroids to leiomyosarcoma is rare. Anatomical imaging with CT or MRI cannot differentiate between larger leiomyoma and leiomyosarcoma. Imaging with F-FDG PET/CT can be helpful in differentiating the two. High-grade F-FDG uptake in uterine fibroids is suspected and warrants surgical excision for further evaluation. We present such as case of a 42-year-old premenopausal woman where F-FDG PET/CT helped in making the diagnosis of malignant degeneration of uterine fibroid. PMID:27556790

  19. FDG PET/CT Findings in Abdominal Fat Necrosis After Treatment for Lymphoma.

    PubMed

    Dubreuil, Julien; Moreau, Aurélie; Sarkozy, Clémentine; Traverse-Glehen, Alexandra; Skanjeti, Andrea; Salles, Gilles; Giammarile, Francesco

    2016-05-01

    FDG PET/CT is now validated in non-Hodgkin lymphoma for response assessment in interim and posttreatment lymphoma. We report the case of a 62-year-old man followed by FDG PET/CT for a diffuse large B-cell lymphoma, with initial stage III. The interim FDG PET/CT examination concluded in complete metabolic and morphological response of subdiaphragmatic lymphadenopathy but a persistent abnormal subdiaphragmatic uptake (SUVmax at 9 and Deauville 5-point scale at 5). Therefore, an abdominal biopsy of the corresponding nodules was conducted with a final diagnosis of diffuse fat necrosis. PMID:26825213

  20. [A case of hepatocellular carcinoma with multiple lymph node metastases detected by FDG-PET].

    PubMed

    Ito, Tadao; Noguchi, Akinori; Shimizu, Takeshi; Tani, Naoki; Yamaguchi, Masahide; Okano, Shinji; Yamane, Tetsuro; Kawabata, Kenji

    2012-11-01

    We report a case of hepatocellular carcinoma (HCC) with multiple lymph node (LN) metastases. A 68-year-old man underwent hepatectomy at our hospital. Intrahepatic recurrence and swelling of multiple LNs were detected by enhanced CT 21 months later. FDG-PET was positive for multiple swollen LNs, but all were negative for the intrahepatic recurrences. Biopsy of para-aortic LNs was revealed LN metastases from HCC. Immunohistochemically, the LN metastases were composed of poorly differentiated HCC. The sensitivity of FDG-PET in patients with HCC varies in relation to degree of differentiation and decreased FDG uptake must be noted. PMID:23132040

  1. Deciphering PDT-induced inflammatory responses using real-time FDG-PET in a mouse tumour model.

    PubMed

    Cauchon, Nicole; Hasséssian, Haroutioun M; Turcotte, Eric; Lecomte, Roger; van Lier, Johan E

    2014-10-01

    Dynamic positron emission tomography (PET), combined with constant infusion of 2-deoxy-2-[(18)F]fluoro-d-glucose (FDG), enables real-time monitoring of transient metabolic changes in vivo, which can serve to understand the underlying physiology. Here we investigated characteristic changes in the tumour FDG-uptake profiles in relation to acute localized inflammatory responses induced by photodynamic therapy (PDT). Dynamic PET imaging with constant FDG infusion was used with EMT-6 tumour bearing mice. FDG time-activity uptake curves were measured simultaneously, in treated and reference tumours, for 3 hours, before, during and after PDT light treatment. Inflammation was studied when evoked, either by PDT using a trisulfonated porphyrazine photosensitizer, or lipopolysaccharide (LPS), and inhibited using indomethacin. The distinct transient patterns, characterized by drops and subsequent recovery of tumour FDG uptake rates, were also analysed using immunohistochemical markers for apoptosis, necrosis, and inflammation. Typical profiles for tumour FDG-uptake, consisted of a drop during PDT, followed by a gradual recovery period. Tumours treated with LPS, but not with light, showed a continuous increase in FDG-uptake during the 3 h experimental period. Treatment with indomethacin, inhibited the rise in FDG-uptake observed with either LPS or PDT. Tumour FDG-uptake profiles correlated with necrosis markers during PDT, and inflammatory response markers post-PDT, but not with an apoptosis marker at any time during or after PDT. Dynamic FDG-PET imaging combined with indomethacin reveals that, the drop in the tumour FDG-uptake rate during the PDT illumination phase reflects vascular collapse and necrosis, while the increased tumour FDG-uptake rate immediately post-illumination involves an acute localized inflammatory response. Dynamic FDG infusion and PET imaging, combined with the use of selective inhibitors, provides unique insight for deciphering the complex underlying

  2. 18F-fluorodeoxyglucose positron emission tomography imaging in brain tumours: the Western Australia positron emission tomography/cyclotron service experience.

    PubMed

    McCarthy, M; Yuan, J B; Campbell, A; Lenzo, N P; Butler-Henderson, K

    2008-12-01

    (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG-PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty-eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow-up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false-negative scans and two false-positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour.

  3. FDG PET/CT response in diffuse large B-cell lymphoma: Reader variability and association with clinical outcome.

    PubMed

    Han, Eun Ji; O, Joo Hyun; Yoon, Hyukjin; Jung, Seung Eun; Park, Gyeongsin; Choi, Byung Ock; Cho, Seok-Goo

    2016-09-01

    F-18-fluoro-2-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is essential for monitoring response to treatment in patients with diffuse large B-cell lymphoma (DLBCL) and qualitative interpretation is commonly applied in clinical practice. We aimed to evaluate the interobserver agreements of qualitative PET/CT response in patients with DLBCL and the predictive value of PET/CT results for clinical outcome.PET/CT images were obtained for patients with DLBCL 3 times: at baseline, after 3 cycles of first-line chemotherapy (interim), and after completion of chemotherapy. Two nuclear medicine physicians (with 3 and 8 years of experience with PET/CT) retrospectively assessed response to chemotherapy blinded to the clinical outcome using International Harmonization Project (IHP) criteria and Deauville 5-point score. The associations between PET/CT results and progression-free survival (PFS) and overall survival (OS) were assessed using Cox regression analysis.A total of 112 PET/CT images were included from 59 patients with DLBCL (36 male, 23 female; mean age 53 ± 14 years). Using the IHP criteria, interobserver agreement was substantial (Cohen κ = 0.76) with absolute agreement consistency of 89%. Using the Deauville score, interobserver agreement was moderate (Cohen weighted κ = 0.54) and absolute consistency was 62%. The most common cause of disagreements was discordant interpretation of residual tumor uptake. With median follow-up period of 60 months, estimated 5-year PFS and OS were 81% and 92%, respectively. Neither interim nor posttreatment PET/CT results by both readers were significantly associated with PFS. Interim PET/CT result by the more experienced reader using Deauville score was a significant factor for OS (P = 0.019).Moderate-to-substantial interobserver agreement was observed for response assessments according to qualitative PET/CT criteria, and interim PET/CT result could predict OS in patients with DLBCL. Further

  4. Discussion on the alteration of FDG uptake by the breast according to the menstrual cycle in 18F-FDG PET/CT

    NASA Astrophysics Data System (ADS)

    Park, H. H.; Park, M. S.; Lee, C. H.; Cho, J. H.; Dong, K. R.; Chung, W. K.

    2012-09-01

    18F-FDG (fluorodeoxyglucose) PET (positron emission tomography)/CT (computed tomography) is a useful modality for identifying high-glucose-consuming cells, such as cancer cells, by the glucose metabolism of FDG. FDG is taken up by cancer and inflammatory cells, but occasionally there is also some FDG uptake by normal tissues as a result of their individual physiological characteristics. In particular, in fertile females, unusual FDG uptake in the breast changes according to the stages in the menstrual cycle, which can adversely affect a diagnosis. Therefore, this study examined the change in breast FDG uptake in the menstrual cycle on 18F-FDG PET/CT. One hundred and sixty females (34±3.5 years old), who had not undergone a gynecologic anamnesis and had a regular menstrual cycle over the previous 6 months, were examined from March 2010 to February 2011. The subjects were divided into the following four groups (each with 40 patients): flow phase, proliferative phase, ovulatory phase and secretory phase using Pregnancy Calculator Ver. 0.14 and history taking. Discovery Ste was used as the PET/CT. The standardized uptake values (SUVs) on the accumulated region on the breast were analyzed, and three nuclear medicine specialists performed a blind test. The SUVs on the breast were the flow phase (1.64±0.25), proliferative phase (0.93±0.28), ovulatory phase (1.66±0.26) and secretory phase (1.77±0.28). A high uptake value was observed in the secretory, flow and ovulatory phases. The FDG accumulation of the breast was divided into the following three grades compared with the lung and liver by gross analysis: the breast uptake was equal to the lung (Grade I), between the lung and liver (Grade II) and equal to or greater than the liver (Grade III). These results showed a high uptake value in the secretory, flow and ovulatory phases. In fertile females, the FDG uptake of the breast showed changes according to the menstrual cycle, which can be used to improve the diagnosis

  5. The F-18 systems research aircraft facility

    NASA Technical Reports Server (NTRS)

    Sitz, Joel R.

    1992-01-01

    To help ensure that new aerospace initiatives rapidly transition to competitive U.S. technologies, NASA Dryden Flight Research Facility has dedicated a systems research aircraft facility. The primary goal is to accelerate the transition of new aerospace technologies to commercial, military, and space vehicles. Key technologies include more-electric aircraft concepts, fly-by-light systems, flush airdata systems, and advanced computer architectures. Future aircraft that will benefit are the high-speed civil transport and the National AeroSpace Plane. This paper describes the systems research aircraft flight research vehicle and outlines near-term programs.

  6. A Pilot Study Treatment of Malignant Tumors Using [18F] Fluorodeoxyglucose (FDG)

    ClinicalTrials.gov

    2016-08-18

    Radiosensitive Stage IV Solid and Hematological Tumors With High FDG Uptake Not Responding to Standard of Care; Lung Cancer, Head and Neck Cancer, Breast Cancer, Gastric Cancer, Pancreatic Cancer, Colon Cancer, Lymphomas, Sarcomas, Etc

  7. Increased 18F-FDG uptake of heterotopic pancreatitis in the small intestine

    PubMed Central

    Ruan, Maomei; Liu, Min; Cheng, Lingxiao; Xie, Wenhui; Chen, Libo

    2016-01-01

    Abstract Backgroud: Heterotopic pancreas (HP), a relatively uncommon congenital anomaly, is rarely noted during 18F-FDG positron-emission tomography/computed tomography (PET/CT) scan. Methods: A 60-year-old woman was referred to our hospital due to a 10-day history of abdominal pain with elevated levels of serum amylase and lipase. Abdominal CT and ultrasound examinations were negative. In order to search for the cause, an 18F-FDG PET/CT whole body scan was suggested to an old woman revealing the presence of 18F-FDG accumulating nodule in small intestine. Results: Surgical findings and pathologic results confirmed the diagnosis of small intestinal heterotopic pancreas with active chronic inflammation. Conclusion: This uncommon case underscores the necessity of considering heterotopic pancreatitis in small intestine with focal 18F-FDG uptake as a possible differential diagnosis in intestinal tumor and tuberculosis. PMID:27603341

  8. The Values and Limitations of FDG-PET/CT for Diagnosis of Hibernoma

    PubMed Central

    Park, Jong Hoon; Ogura, Koichi; Fujiwara, Tomohiro; Nagano, Akihito; Numoto, Kunihiko; Terauchi, Takashi; Yoshida, Akihiko; Kawai, Akira

    2015-01-01

    Hibernoma is a rare benign lipogenic tumor of brown fat that develops in a wide variety of locations. Although the features of hibernoma demonstrated by MRI resemble those of liposarcoma, recent FDG-PET/CT studies have documented higher radiotracer uptake than liposarcoma, suggesting that FDG/PET/CT is useful for differentiating hibernoma from liposarcoma. Here we report two cases of hibernoma that showed relatively lower SUVs than those reported previously, lying within the range for liposarcoma. Our findings emphasize that hibernoma needs to be included in the differential diagnosis of any fat-containing tumor showing intense accumulation by FDG-PET/CT. Although it is unlikely that such a rare condition could be reasonably diagnosed on the basis of MRI and FDG-PET/CT alone due to possible SUV overlap between hibernoma and liposarcoma, it is important to recognize this extremely rare lipogenic tumor for accurate diagnosis and appropriate management. PMID:26783480

  9. Brain herniation

    MedlinePlus

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  10. 18F-FDG PET/CT in patients with adult-onset Still's disease.

    PubMed

    Dong, Meng-Jie; Wang, Cai-Qin; Zhao, Kui; Wang, Guo-Lin; Sun, Mei-Ling; Liu, Zhen-Feng; Xu, Liqin

    2015-12-01

    (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) has become useful for the detection and diagnosis of inflammatory conditions, including rheumatic diseases, immunoglobulin (Ig) G4-related disease and giant cell arteritis. However, few articles based on small sample sizes (n = 7) diagnosed as adult-onset Still's disease (AOSD) have been published. The study aim was to observe the reliable characteristics and usefulness of (18)F-FDG PET/CT for the evaluation of consecutive patients with AOSD. Eligible patients were selected from among those who had undergone (18)F-FDG PET/CT between May 2007 and June 2014. Twenty-six consecutive AOSD patients were recruited retrospectively according to criteria set by Yamaguchi et al. All patients underwent evaluation by (18)F-FDG PET/CT. The characteristics and usefulness of (18)F-FDG PET/CT for evaluation of consecutive patients with AOSD were evaluated. All 26 patients had (18)F-FDG-avid lesion(s) related to their particular disease. Diffuse and homogeneous accumulation of (18)F-FDG was seen in the bone marrow (26/26; 100 %; maximum standardized uptake (SUVmax), 2.10-6.73) and spleen (25/26; 96.15 %). The SUVmax of affected lymph nodes was 1.3-9.53 (mean ± SD, 4.12 ± 2.24). The SUVmax and size factors (maximum diameter and areas) of affected lymph nodes were significantly different (P = 0.033 and P = 0.012, respectively). (18)F-FDG PET/CT showed the general distribution of (18)F-FDG accumulation. This factor helped to exclude malignant disease and aided the diagnosis of AOSD (42.3 %) in 11 cases when combined with clinical features and aided decisions regarding appropriate biopsy sites, such as the lymph nodes (n = 9) and bone marrow (n = 13). (18)F-FDG PET/CT is a unique imaging method for the assessment of metabolic activity throughout the body in subjects with AOSD. Characteristics or patterns of AOSD observed on (18)F-FDG PET/CT can be used for the

  11. Anterior brain glucose hypometabolism predates dementia in progranulin mutation carriers

    PubMed Central

    Hsiung, Ging-Yuek R.; Tawankanjanachot, Itthipol; Dinelle, Katie; McCormick, Siobhan; Gonzalez, Marjorie; Lee, Hyunsoo; Sengdy, Pheth; Bouchard-Kerr, Phoenix; Baker, Matthew; Rademakers, Rosa; Sossi, Vesna; Stoessl, A. Jon; Feldman, Howard H.; Mackenzie, Ian R.

    2013-01-01

    Objective: In this prospective cohort study, we investigated cerebral glucose metabolism reductions on [18F]-fluorodeoxyglucose (FDG)-PET in progranulin (GRN) mutation carriers prior to frontotemporal dementia (FTD) onset. Methods: Nine mutation carriers (age 51.5 ± 13.5 years) and 11 noncarriers (age 52.7 ± 9.5 years) from 5 families with FTD due to GRN mutations underwent brain scanning with FDG-PET and MRI and clinical evaluation. Normalized FDG uptake values were calculated with reference to the pons. PET images were analyzed with regions of interest (ROI) and statistical parametric mapping (SPM) approaches. Results: Compared with noncarriers, GRN mutation carriers had a lowered anterior-to-posterior (AP) ratio of FDG uptake (0.86 ± 0.09 vs 0.92 ± 0.05) and less left-right asymmetry, consistent with an overall pattern of right anterior cerebral hypometabolism. This pattern was observed regardless of whether they were deemed clinically symptomatic no dementia or asymptomatic. Individual ROIs with lowered FDG uptake included right anterior cingulate, insula, and gyrus rectus. SPM analysis supported and extended these findings, demonstrating abnormalities in the right and left medial frontal regions, right insular cortex, right precentral and middle frontal gyri, and right cerebellum. Right AP ratio was correlated with cognitive and clinical scores (modified Mini-Mental State Examination r = 0.74; Functional Rating Scale r = −0.73) but not age and years to estimated onset in mutation carriers. Conclusion: The frontotemporal lobar degenerative process associated with GRN mutations appears to begin many years prior to the average age at FTD onset (late 50s–early 60s). Right medial and ventral frontal cortex and insula may be affected in this process but the specific regional patterns associated with specific clinical variants remain to be elucidated. PMID:24005336

  12. Analysis of glucose metabolism of (18)F-FDG in major depression patients using PET imaging: Correlation of salivary cortisol and α-amylase.

    PubMed

    Wei, Kai; Xue, Hong-Li; Guan, Yi-Hui; Zuo, Chuan-Tao; Ge, Jing-Jie; Zhang, Hong-Ying; Liu, Bao-Jun; Cao, Yu-Xue; Dong, Jing-Cheng; Du, Yi-Jie

    2016-08-26

    Current diagnosis of Major depressive disorder (MDD) depends on its clinical symptoms, not on the results of any laboratory examinations. Establishing biological markers for diagnosis of MDD is one of the most important problems to be solved in psychiatry practice. MDD patients (n=8) and a healthy control group (n=8) were recruited in this study. Hamilton Depression Rating Scale (HAM-D) assessments were completed and saliva samples were collected for assessments of salivary cortisol and salivary α-amylase (sAA). PET examination was performed. Salivary cortisol and sAA in the MDD patients group were significantly higher than the healthy control group (P<0.001). MDD patients showed lower glucose metabolism of 18F-FDG in Cingulate Gyrus (BA24), Superior Frontal Gyrus (BA6), Rectal Gyrus (BA11) and Orbital Gyrus (BA11/47) compared with the healthy control group. The severity of depression, salivary cortisol and sAA correlated negatively with regional glucose metabolism in Cingulate Gyrus (BA 24), Superior Frontal Gyrus (BA 6), Rectal Gyrus (BA 11) and Orbital Gyrus (BA 11/47). The combination of salivary cortisol, sAA, superior frontal gyrus and rectal gyrus was the potential predictor of depression for MDD patients (ΔR(2)=0.981, p<0.001). The present study showed that, MDD patients group showed higher salivary cortisol, sAA levels and lower glucose metabolism of (18)F-FDG in several brain areas compared with the healthy control group. The combination of salivary cortisol, sAA, glucose metabolism of (18)F-FDG of superior frontal gyrus and rectal gyrus may serve as a simple clinical tool for the early diagnosis of MDD. PMID:27373590

  13. Imaging of the myocardium using (18)F-FDG-PET/MRI.

    PubMed

    Ferda, Jiří; Hromádka, Milan; Baxa, Jan

    2016-10-01

    The introduction of the integrated hybrid PET/MRI equipment creates the possibility to perform PET and MRI simultaneously. Depending on the clinical question, the metabolic conversion to glycolytic activity or beta-oxidation is performed before the application of FDG. Since FDG aids to evaluate the energetic metabolism of the myocytes and myocardial MRI reaches the imaging capabilities of perfusion and tissue characterization in the daily routine, FDG-PET/MRI looks to be a promising method of PET/MRI exploitation in cardiac imaging. When myocardial FDG uptake should be evaluated in association with the perfusion distribution, the cross-evaluation of FDG accumulation distribution and perfusion distribution pattern is necessary. The different scenarios may be used in the assessment of myocardium, the conversion to glycolytic activity is used in the imaging of the viable myocardium, but the glycolytic activity suppression might be used in the indications of the identification of injured myocardium by ischemia or inflammation. FDG-PET/MRI might aid to answer the clinical tasks according to the structure, current function and possibilities to improve the function in ischemic heart disease or to display the extent or activity of myocardial inflammation in sarcoidosis. The tight coupling between metabolism, perfusion and contractile function offers an opportunity for the simultaneous assessment of cardiac performance using one imaging modality. PMID:27470994

  14. Two years of experience with the [ 18F]FDG production module

    NASA Astrophysics Data System (ADS)

    Kim, Sang Wook; Hur, Min Goo; Chai, Jong-Seo; Park, Jeong Hoon; Yu, Kook Hyun; Jeong, Cheol Ki; Lee, Goung Jin; Min, Young Don; Yang, Seung Dae

    2007-08-01

    Chemistry module for a conventional [18F]FDG production by using tetrabutylammonium bicarbonate (TBA) and an acidic hydrolysis has been manufactured and evaluated. In this experiment, 75 mM (pH 7.5-7.8) of TBA solution and a ca. 2-curies order of [18F]-fluoride have been used for the evaluation. The commercial acidic purification cartridge was purchased from GE or UKE. The operation system (OS) was programmed with Lab-View which was selected because of its easy customization of the OS. Small sized solenoid valves (Burkert; type 6124) were selected to reduce the module dimensions (W 350 × D 270 × H 250). The total time for the synthesis of [18F]FDG was 30 ± 3 min. The production yield of [18F]FDG was 60 ± 2% on an average at EOS, with the decay uncorrected. This experimental data show that the traditional chemistry module can provide a good [18F]FDG production yield by optimizing the operational conditions. The radiochemical purity, radionuclidic purity, acidity, residual solvent, osmolality and endotoxin were determined to assess the quality of [18F]FDG. The examined contents for the quality control of [18F]FDG were found to be suitable for a clinical application.

  15. Imaging of the myocardium using (18)F-FDG-PET/MRI.

    PubMed

    Ferda, Jiří; Hromádka, Milan; Baxa, Jan

    2016-10-01

    The introduction of the integrated hybrid PET/MRI equipment creates the possibility to perform PET and MRI simultaneously. Depending on the clinical question, the metabolic conversion to glycolytic activity or beta-oxidation is performed before the application of FDG. Since FDG aids to evaluate the energetic metabolism of the myocytes and myocardial MRI reaches the imaging capabilities of perfusion and tissue characterization in the daily routine, FDG-PET/MRI looks to be a promising method of PET/MRI exploitation in cardiac imaging. When myocardial FDG uptake should be evaluated in association with the perfusion distribution, the cross-evaluation of FDG accumulation distribution and perfusion distribution pattern is necessary. The different scenarios may be used in the assessment of myocardium, the conversion to glycolytic activity is used in the imaging of the viable myocardium, but the glycolytic activity suppression might be used in the indications of the identification of injured myocardium by ischemia or inflammation. FDG-PET/MRI might aid to answer the clinical tasks according to the structure, current function and possibilities to improve the function in ischemic heart disease or to display the extent or activity of myocardial inflammation in sarcoidosis. The tight coupling between metabolism, perfusion and contractile function offers an opportunity for the simultaneous assessment of cardiac performance using one imaging modality.

  16. Breast Sparganosis Incidentally Detected by FDG PET/CT.

    PubMed

    Ha, Seunggyun; Oh, So Won; Kim, Yu Kyeong; Yi, Ann; Ahn, Young Joon

    2013-06-01

    Sparganosis is a rare, parasitic infection that is caused by the plercercoid tapeworm larvae of the genus Spirometra. Sparganosis is transmitted by ingestion of larvae-containing water or intermediate hosts, such as raw amphibians, and usually presented with a subcutaneous nodule in the abdominal wall, extremities, and genital organs. Among the various involved organs, the breast is a seldom encountered site for sparganosis. However, breast sparganosis has clinical importance, since it is generally presented with an indolent palpable mass that mimics malignancy, even without evidence of inflammation. Herein, we report a case of breast sparganosis that was detected incidentally by FDG PET/CT during staging work ups in a patient with gall bladder cancer. PMID:24900094

  17. Increased FDG uptake of the bone marrow mimicking malignancy in a patient of eosinophilia secondary to Sparganum mansoni infection.

    PubMed

    Dong, Aisheng; Wang, Yang; Gao, Lei; Zuo, Changjing

    2014-07-01

    Secondary eosinophilia is usually associated with parasitosis in Third World countries. We present a case of eosinophilia secondary to Sparganum mansoni infection showing multifocal FDG uptake in the axial bones mimicking malignancy. Bone marrow aspirations and biopsy revealed remarkable proliferation of eosinophils which may be related to the increased FDG uptake. This case indicates that secondary eosinophilia associated with parasitosis may be one cause of diffuse FDG uptake in the bone marrow.

  18. Multimodal Imaging of Alzheimer Pathophysiology in the Brain's Default Mode Network

    DOE PAGES

    Shin, Jonghan; Kepe, Vladimir; Small, Gary W.; Phelps, Michael E.; Barrio, Jorge R.

    2011-01-01

    The spatial correlations between the brain's default mode network (DMN) and the brain regions known to develop pathophysiology in Alzheimer's disease (AD) have recently attracted much attention. In this paper, we compare results of different functional and structural imaging modalities, including MRI and PET, and highlight different patterns of anomalies observed within the DMN. Multitracer PET imaging in subjects with and without dementia has demonstrated that [C-11]PIB- and [F-18]FDDNP-binding patterns in patients with AD overlap within nodes of the brain's default network including the prefrontal, lateral parietal, lateral temporal, and posterior cingulate cortices, with the exception of the medial temporalmore » cortex (especially, the hippocampus) where significant discrepancy between increased [F-18]FDDNP binding and negligible [C-11]PIB-binding was observed. [F-18]FDDNP binding in the medial temporal cortex—a key constituent of the DMN—coincides with both the presence of amyloid and tau pathology, and also with cortical areas with maximal atrophy as demonstrated by T1-weighted MR imaging of AD patients.« less

  19. Applications of 2-deoxy-2-fluoro-D-glucose (FDG) in Plant Imaging: Past, Present, and Future

    PubMed Central

    Fatangare, Amol; Svatoš, Aleš

    2016-01-01

    The aim of this review article is to explore and establish the current status of 2-deoxy-2-fluoro-D-glucose (FDG) applications in plant imaging. In the present article, we review the previous literature on its experimental merits to formulate a consistent and inclusive picture of FDG applications in plant-imaging research. 2-deoxy-2-fluoro-D-glucose is a [18F]fluorine-labeled glucose analog in which C-2 hydroxyl group has been replaced by a positron-emitting [18F] radioisotope. As FDG is a positron-emitting radiotracer, it could be used in in vivo imaging studies. FDG mimics glucose chemically and structurally. Its uptake and distribution are found to be similar to those of glucose in animal models. FDG is commonly used as a radiotracer for glucose in medical diagnostics and in vivo animal imaging studies but rarely in plant imaging. Tsuji et al. (2002) first reported FDG uptake and distribution in tomato plants. Later, Hattori et al. (2008) described FDG translocation in intact sorghum plants and suggested that it could be used as a tracer for photoassimilate translocation in plants. These findings raised interest among other plant scientists, which has resulted in a recent surge of articles involving the use of FDG as a tracer in plants. There have been seven studies describing FDG-imaging applications in plants. These studies describe FDG applications ranging from monitoring radiotracer translocation to analyzing solute transport, root uptake, photoassimilate tracing, carbon allocation, and glycoside biosynthesis. Fatangare et al. (2015) recently characterized FDG metabolism in plants; such knowledge is crucial to understanding and validating the application of FDG in plant imaging research. Recent FDG studies significantly advance our understanding of FDG translocation and metabolism in plants but also raise new questions. Here, we take a look at all the previous results to form a comprehensive picture of FDG translocation, metabolism, and applications in

  20. Neurometabolic effects of psilocybin, 3,4-methylenedioxyethylamphetamine (MDE) and d-methamphetamine in healthy volunteers. A double-blind, placebo-controlled PET study with [18F]FDG.

    PubMed

    Gouzoulis-Mayfrank, E; Schreckenberger, M; Sabri, O; Arning, C; Thelen, B; Spitzer, M; Kovar, K A; Hermle, L; Büll, U; Sass, H

    1999-06-01

    The neurometabolic effects of the hallucinogen psilocybin (PSI; 0.2 mg/kg), the entactogen 3,4-methylenedioxyethylamphetamine (MDE; 2 mg/kg) and the stimulant d-methamphetamine (METH; 0.2-0.4 mg/kg) and the drugs' interactions with a prefrontal activation task were investigated in a double-blind, placebo-controlled human [F-18]fluorodeoxyglucoseFDG-positron emission tomographicPET study (each group: n = 8). Subjects underwent two scans (control: word repetition; activation word association) within 2-4 weeks. Psilocybin increased rMRGlu in distinct right hemispheric frontotemporal cortical regions, particularly in the anterior cingulate and decreased rMRGlu in the thalamus. Both MDE and METH induced cortical hypometabolism and cerebellar hypermetabolism. In the MDE group, cortical hypometabolism was more pronounced in frontal regions, with the exception of the right anterior cingulate, which tended to be hyperactive. Cognitive activation-related increases in left frontocortical regions were attenuated under all three psychoactive substances, but less so under MDE. Taking into account performance data and subjective reports on task difficulty, these effects may result from different mechanisms across the three groups. Our PSI data are in line with studies on acute schizophrenic patients suggesting frontal overactivity at rest, but diminished capacity to activate prefrontal regions upon cognitive demand. The MDE data support the hypothesis that entactogens constitute a distinct psychoactive substance class, which takes an intermediate position between stimulants and hallucinogens.

  1. Amorphous fluorocarbon polymer (a-C:F) films obtained by plasma enhanced chemical vapor deposition from perfluoro-octane (C8F18) vapor I: Deposition, morphology, structural and chemical properties

    NASA Astrophysics Data System (ADS)

    Biloiu, Costel; Biloiu, Ioana Arabela; Sakai, Yosuke; Suda, Yoshiyuki; Ohta, Akitsugu

    2004-01-01

    The method of obtaining amorphous fluorocarbon polymer (a-C:F) films by plasma enhanced chemical vapor deposition in a capacitively coupled, 13.56 MHz reactor, from a new monomer, namely perfluoro-octane (C8F18) vapor, is presented. For monomer pressure ranging from 0.2 to 1 Torr and input power density from 0.15 to 0.85 W/cm3, the maximum deposition rate reached 300 nm/min, while 10% monomer dilution with argon led to a deposition rate of 200 nm/min. The film surface and bulk morphologies, chemical and structural compositions were investigated using scanning electron microscopy, x-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. It was revealed that the films have a dense and compact structure. The fluorine to carbon ratio (F/C) of the films was between 1.57 and 1.75, and the degree of cross-linking was between 55% and 58%. The relative amount of perfluoroalkyl (CF2) groups in the films was 29%. The FTIR spectra showed absorption bands corresponding to the different vibrational modes of CF, CF2, and CF3 moieties. .

  2. Different partial volume correction methods lead to different conclusions: An (18)F-FDG-PET study of aging.

    PubMed

    Greve, Douglas N; Salat, David H; Bowen, Spencer L; Izquierdo-Garcia, David; Schultz, Aaron P; Catana, Ciprian; Becker, J Alex; Svarer, Claus; Knudsen, Gitte M; Sperling, Reisa A; Johnson, Keith A

    2016-05-15

    A cross-sectional group study of the effects of aging on brain metabolism as measured with (18)F-FDG-PET was performed using several different partial volume correction (PVC) methods: no correction (NoPVC), Meltzer (MZ), Müller-Gärtner (MG), and the symmetric geometric transfer matrix (SGTM) using 99 subjects aged 65-87years from the Harvard Aging Brain study. Sensitivity to parameter selection was tested for MZ and MG. The various methods and parameter settings resulted in an extremely wide range of conclusions as to the effects of age on metabolism, from almost no changes to virtually all of cortical regions showing a decrease with age. Simulations showed that NoPVC had significant bias that made the age effect on metabolism appear to be much larger and more significant than it is. MZ was found to be the same as NoPVC for liberal brain masks; for conservative brain masks, MZ showed few areas correlated with age. MG and SGTM were found to be similar; however, MG was sensitive to a thresholding parameter that can result in data loss. CSF uptake was surprisingly high at about 15% of that in gray matter. The exclusion of CSF from SGTM and MG models, which is almost universally done, caused a substantial loss in the power to detect age-related changes. This diversity of results reflects the literature on the metabolism of aging and suggests that extreme care should be taken when applying PVC or interpreting results that have been corrected for partial volume effects. Using the SGTM, significant age-related changes of about 7% per decade were found in frontal and cingulate cortices as well as primary visual and insular cortices. PMID:26915497

  3. Central modulation in cluster headache patients treated with occipital nerve stimulation: an FDG-PET study

    PubMed Central

    2011-01-01

    Background Occipital nerve stimulation (ONS) has raised new hope for drug-resistant chronic cluster headache (drCCH), a devastating condition. However its mode of action remains elusive. Since the long delay to meaningful effect suggests that ONS induces slow neuromodulation, we have searched for changes in central pain-control areas using metabolic neuroimaging. Methods Ten drCCH patients underwent an 18FDG-PET scan after ONS, at delays varying between 0 and 30 months. All were scanned with ongoing ONS (ON) and with the stimulator switched OFF. Results After 6-30 months of ONS, 3 patients were pain free and 4 had a ≥ 90% reduction of attack frequency (responders). In all patients compared to controls, several areas of the pain matrix showed hypermetabolism: ipsilateral hypothalamus, midbrain and ipsilateral lower pons. All normalized after ONS, except for the hypothalamus. Switching the stimulator ON or OFF had little influence on brain glucose metabolism. The perigenual anterior cingulate cortex (PACC) was hyperactive in ONS responders compared to non-responders. Conclusions Metabolic normalization in the pain neuromatrix and lack of short-term changes induced by the stimulation might support the hypothesis that ONS acts in drCCH through slow neuromodulatory processes. Selective activation in responders of PACC, a pivotal structure in the endogenous opioid system, suggests that ONS could restore balance within dysfunctioning pain control centres. That ONS is nothing but a symptomatic treatment might be illustrated by the persistent hypothalamic hypermetabolism, which could explain why autonomic attacks may persist despite pain relief and why cluster attacks recur shortly after stimulator arrest. PET studies on larger samples are warranted to confirm these first results. PMID:21349186

  4. FDG-PET on the trail of an unsuspected primary malignancy in the breast.

    PubMed

    Dockery, Keith F; Puri, Savita; Qazi, Raman; Davis, Delphine

    2008-03-01

    Proper identification of the primary malignancy can radically alter clinical management for the patient's benefit. This is a report of an unsuspected primary breast cancer in a patient being worked up for presumptive lymphoma. Prior investigation of lymphedema in the left lower extremity found widespread lymphadenopathy on computed tomography imaging, leading to initial biopsy revealing adenocarcinoma of unknown primary. F-18 fluorodeoxyglucose PET/computed tomography altered management by localizing an F-18 fluorodeoxyglucose avid breast nodule, directing breast biopsy with specific immunohistochemical analysis for breast cancer lineage in metastatic adenocarcinoma. The patient responded well to breast cancer-targeted chemotherapy.

  5. Association of Heat Production with FDG Accumulation by Murine Brown Adipose Tissue (BAT) After Stress

    PubMed Central

    Carter, Edward A.; Bonab, Ali A; Paul, Kasie; Yerxa, John; Tompkins, Ronald G.; Fischman, Alan J.

    2014-01-01

    Previous studies have demonstrated that cold stress results in increased accumulation of 18FDG in brown adipose tissue (BAT). Although it has been assumed that this effect is associated with increased thermogenesis by BAT, direct measurements of this phenomenon have not been reported. In the current investigation we evaluated the relationship between stimulation of 18FDG accumulation in BAT by three stressors and heat production measured in vivo by thermal imaging. Male SKH-1 hairless mice were subjected to full-thickness thermal injury (30% total body surface area), cold stress (4°C for 24 hours), or cutaneous wounds. Groups of 6 animals with each treatment were fasted over night and injected with 18FDG. Sixty minutes after injection the mice were sacrificed and biodistribution was measured. Other groups of six animals subjected to the three stressors were studied by thermal imaging and the difference in temperature between BAT and adjacent tissue was recorded (ΔT). Additional groups of 6 animals were studied by both thermal imaging and 18FDG biodistribution in the same animals. Accumulation of 18FDG by BAT was significantly (p <0.0001) increased by all 3 treatments (burn ~5 fold, cold: ~15 fold, and cutaneous wound ~15 fold) whereas accumulation by adjacent white adipose tissue (WAT) was unchanged. Compared with sham control mice; ΔTs in animals exposed to all three stressors showed significant (p<0.001) increases in temperature between BAT and adjacent tissue. The difference in ΔT between stressor groups was not significant, however, there was a highly significant linear correlation (r2=0.835, p<0.0001) between the ΔT measured in BAT vs. adjacent tissue and 18FDG accumulation. These results establish, for the first time, that changes in BAT temperature determined in vivo by thermal imaging parallel increases in 18FDG accumulation. PMID:21914754

  6. Does Delayed-Time-Point Imaging Improve 18F-FDG-PET in Patients With MALT Lymphoma?

    PubMed Central

    Mayerhoefer, Marius E.; Giraudo, Chiara; Senn, Daniela; Hartenbach, Markus; Weber, Michael; Rausch, Ivo; Kiesewetter, Barbara; Herold, Christian J.; Hacker, Marcus; Pones, Matthias; Simonitsch-Klupp, Ingrid; Müllauer, Leonhard; Dolak, Werner; Lukas, Julius; Raderer, Markus

    2016-01-01

    Purpose To determine whether in patients with extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue lymphoma (MALT), delayed–time-point 2-18F-fluoro-2-deoxy-d-glucose-positron emission tomography (18F-FDG-PET) performs better than standard–time-point 18F-FDG-PET. Materials and Methods Patients with untreated histologically verified MALT lymphoma, who were undergoing pretherapeutic 18F-FDG-PET/computed tomography (CT) and consecutive 18F-FDG-PET/magnetic resonance imaging (MRI), using a single 18F-FDG injection, in the course of a larger-scale prospective trial, were included. Region-based sensitivity and specificity, and patient-based sensitivity of the respective 18F-FDG-PET scans at time points 1 (45–60 minutes after tracer injection, TP1) and 2 (100–150 minutes after tracer injection, TP2), relative to the reference standard, were calculated. Lesion-to-liver and lesion-to-blood SUVmax (maximum standardized uptake values) ratios were also assessed. Results 18F-FDG-PET at TP1 was true positive in 15 o f 23 involved regions, and 18F-FDG-PET at TP2 was true-positive in 20 of 23 involved regions; no false-positive regions were noted. Accordingly, region-based sensitivities and specificities were 65.2% (confidence interval [CI], 45.73%–84.67%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP1; and 87.0% (CI, 73.26%–100%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP2, respectively. FDG-PET at TP1 detected lymphoma in at least one nodal or extranodal region in 7 of 13 patients, and 18F-FDG-PET at TP2 in 10 of 13 patients; accordingly, patient-based sensitivity was 53.8% (CI, 26.7%–80.9%) for 18F-FDG-PET at TP1, and 76.9% (CI, 54.0%–99.8%) for 18F-FDG-PET at TP2. Lesion-to-liver and lesion-to-blood maximum standardized uptake value ratios were significantly lower at TP1 (ratios, 1.05 ± 0.40 and 1.52 ± 0.62) than at TP2 (ratios, 1.67 ± 0.74 and 2.56 ± 1.10; P = 0.003 and P = 0.001). Conclusions Delayed–time-point imaging

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

    PubMed Central

    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

  8. Brain Tumors

    MedlinePlus

    A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, ... cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are ...

  9. FDG PET with contrast-enhanced CT: a critical imaging tool for laryngeal carcinoma.

    PubMed

    Chu, Mae Mae A Y; Kositwattanarerk, Arpakorn; Lee, David J; Makkar, Jasnit S; Genden, Eric M; Kao, Johnny; Packer, Stuart H; Som, Peter M; Kostakoglu, Lale

    2010-09-01

    Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) has evolved to be an essential imaging modality in the evaluation of laryngeal carcinoma. Although the modality has limited utility in assessing the extent of the primary tumor, FDG PET has proved to be superior to anatomic modalities in the detection of lymph node and distant metastases. The role of FDG PET in the evaluation of patients with laryngeal tumors that are clinically classified as N0 has not shown consistent usefulness because of the innate resolution limitations of the camera. In the posttherapy setting, however, FDG PET has consistently demonstrated a high negative predictive value in the identification of recurrent disease, both during the course of therapy and during long-term follow-up. In addition, contrast material-enhanced computed tomography (CT) in conjunction with FDG PET has demonstrated a complementary role by allowing for superior anatomic coregistration and therefore more definitive diagnosis. There is sufficient evidence that with further advances in PET technology, this modality will likely become more useful in the detection of small lesions and occult nodal disease, as well as in guiding the management of laryngeal carcinoma. PMID:20833855

  10. Bone marrow metastases from alveolar rhabdomyosarcoma with impressive FDG PET/CT finding but less-revealing bone scintigraphy.

    PubMed

    Yang, Jigang; Zhen, Lishi; Zhuang, Hongming

    2013-12-01

    An 18F-FDG PET/CT scan was performed in a 26-year-old man with a known alveolar rhabdomyosarcoma for staging. The PET/CT scan showed abnormally increased FDG activity involving almost all bones in the imaged regions. In contrast, 99mTc-MDP whole-body bone scan demonstrated only very limited bone metastases.

  11. Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers

    PubMed Central

    Kito, Shinji; Koga, Hirofumi; Kodama, Masaaki; Habu, Manabu; Kokuryo, Shinya; Oda, Masafumi; Matsuo, Kou; Nishino, Takanobu; Matsumoto-Takeda, Shinobu; Uehara, Masataka; Yoshiga, Daigo; Tanaka, Tatsurou; Nishimura, Shun; Miyamoto, Ikuya; Sasaguri, Masaaki; Tominaga, Kazuhiro; Yoshioka, Izumi; Morimoto, Yasuhiro

    2016-01-01

    Background 18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. Material and Methods 18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. Results According to the extent of ND of cervical lymph nodes, the rate of patients with 18F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND. Conclusions In evaluating 18F-FDG accumulations after ND for oral cancers, we should pay attention to the 18F-FDG distributions in neck-related muscles including the non-surgical side as false-positive findings. Key words:18F-FDG, PET-CT, oral cancers, muscles. PMID:27031062

  12. Cytochrome P-450 4F18 is the leukotriene B4 omega-1/omega-2 hydroxylase in mouse polymorphonuclear leukocytes: identification as the functional orthologue of human polymorphonuclear leukocyte CYP4F3A in the down-regulation of responses to LTB4.

    PubMed

    Christmas, Peter; Tolentino, Karine; Primo, Valeria; Berry, Karin Zemski; Murphy, Robert C; Chen, Mei; Lee, David M; Soberman, Roy J

    2006-03-17

    Leukotriene B(4) (LTB(4)) is a potent chemoattractant for polymorphonuclear leukocytes (PMN) and other cells. Human PMN inactivate LTB(4) by omega-oxidation catalyzed by cytochrome P-450 (CYP) 4F3A. The contribution of the enzymatic inactivation of LTB(4) by CYP4Fs to down-regulating functional responses of cells to LTB(4) is unknown. To elucidate the role of CYP4F-mediated inactivation of LTB(4) in terminating the responses of PMN to LTB(4) and to identify a target for future genetic studies in mice, we have identified the enzyme that catalyzes the omega-1 and omega-2 oxidation of LTB(4) in mouse myeloid cells as CYP4F18. As determined by mass spectrometry, this enzyme catalyzes the conversion of LTB(4) to 19-OH LTB(4) and to a lesser extent 18-OH LTB(4). Inhibition of CYP4F18 resulted in a marked increase in calcium flux and a 220% increase in the chemotactic response of mouse PMN to LTB(4). CYP4F18 expression was induced in bone marrow-derived dendritic cells by bacterial lipopolysaccharide, a ligand for TLR4, and by poly(I.C), a ligand for TLR3. However, when bone marrow-derived myeloid dendritic cells trafficked to popliteal lymph nodes from paw pads, the expression of CYP4F18 was down-regulated. The results identify CYP4F18 as a critical protein in the regulation of LTB(4) metabolism and functional responses in mouse PMN and identify it as the functional orthologue of human PMN CYP4F3A.

  13. The Minimal Energetic Requirement of Sustained Awareness after Brain Injury.

    PubMed

    Stender, Johan; Mortensen, Kristian Nygaard; Thibaut, Aurore; Darkner, Sune; Laureys, Steven; Gjedde, Albert; Kupers, Ron

    2016-06-01

    Differentiation of the minimally conscious state (MCS) and the unresponsive wakefulness syndrome (UWS) is a persistent clinical challenge [1]. Based on positron emission tomography (PET) studies with [(18)F]-fluorodeoxyglucose (FDG) during sleep and anesthesia, the global cerebral metabolic rate of glucose has been proposed as an indicator of consciousness [2, 3]. Likewise, FDG-PET may contribute to the clinical diagnosis of disorders of consciousness (DOCs) [4, 5]. However, current methods are non-quantitative and have important drawbacks deriving from visually guided assessment of relative changes in brain metabolism [4]. We here used FDG-PET to measure resting state brain glucose metabolism in 131 DOC patients to identify objective quantitative metabolic indicators and predictors of awareness. Quantitation of images was performed by normalizing to extracerebral tissue. We show that 42% of normal cortical activity represents the minimal energetic requirement for the presence of conscious awareness. Overall, the cerebral metabolic rate accounted for the current level, or imminent return, of awareness in 94% of the patient population, suggesting a global energetic threshold effect, associated with the reemergence of consciousness after brain injury. Our data further revealed that regional variations relative to the global resting metabolic level reflect preservation of specific cognitive or sensory modules, such as vision and language comprehension. These findings provide a simple and objective metabolic marker of consciousness, which can readily be implemented clinically. The direct correlation between brain metabolism and behavior further suggests that DOCs can fundamentally be understood as pathological neuroenergetic conditions and provide a unifying physiological basis for these syndromes. PMID:27238279

  14. The Minimal Energetic Requirement of Sustained Awareness after Brain Injury.

    PubMed

    Stender, Johan; Mortensen, Kristian Nygaard; Thibaut, Aurore; Darkner, Sune; Laureys, Steven; Gjedde, Albert; Kupers, Ron

    2016-06-01

    Differentiation of the minimally conscious state (MCS) and the unresponsive wakefulness syndrome (UWS) is a persistent clinical challenge [1]. Based on positron emission tomography (PET) studies with [(18)F]-fluorodeoxyglucose (FDG) during sleep and anesthesia, the global cerebral metabolic rate of glucose has been proposed as an indicator of consciousness [2, 3]. Likewise, FDG-PET may contribute to the clinical diagnosis of disorders of consciousness (DOCs) [4, 5]. However, current methods are non-quantitative and have important drawbacks deriving from visually guided assessment of relative changes in brain metabolism [4]. We here used FDG-PET to measure resting state brain glucose metabolism in 131 DOC patients to identify objective quantitative metabolic indicators and predictors of awareness. Quantitation of images was performed by normalizing to extracerebral tissue. We show that 42% of normal cortical activity represents the minimal energetic requirement for the presence of conscious awareness. Overall, the cerebral metabolic rate accounted for the current level, or imminent return, of awareness in 94% of the patient population, suggesting a global energetic threshold effect, associated with the reemergence of consciousness after brain injury. Our data further revealed that regional variations relative to the global resting metabolic level reflect preservation of specific cognitive or sensory modules, such as vision and language comprehension. These findings provide a simple and objective metabolic marker of consciousness, which can readily be implemented clinically. The direct correlation between brain metabolism and behavior further suggests that DOCs can fundamentally be understood as pathological neuroenergetic conditions and provide a unifying physiological basis for these syndromes.

  15. Brain surgery

    MedlinePlus

    Craniotomy; Surgery - brain; Neurosurgery; Craniectomy; Stereotactic craniotomy; Stereotactic brain biopsy; Endoscopic craniotomy ... cut depends on where the problem in the brain is located. The surgeon creates a hole in ...

  16. Brain Malformations

    MedlinePlus

    Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

  17. ACR-ASNR Practice Parameter for Brain PET/CT Imaging Dementia.

    PubMed

    Frey, Kirk A; Lodge, Martin A; Meltzer, Carolyn Cidis; Peller, Patrick J; Wong, Terence Z; Hess, Christopher P; Petrella, Jeffrey R; Sair, Haris I; Subramaniam, Rathan M

    2016-02-01

    This practice parameter is for both FDG and amyloid brain PET or PET/computed tomography (CT) for patients with cognitive decline, and has been developed collaboratively by the American College of Radiology (ACR) and the American Society for Neuroradiology (ASNR). It is estimated that the number of people with dementia, 36.5 million worldwide in 2010, will increase to 65.7 million in 2030 and to 115 million in 2050. Four primary neurodegenerative etiologies of dementia have been defined: Alzheimer disease (AD), vascular dementia, frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB). Alzheimer disease is the most common form of dementia, accounting for approximately 60%-80% of all cases. Indications for FDG and amyloid brain PET and qualifications for personnel are discussed in this practice parameter.

  18. Reproducibility of regional brain metabolic responses to lorazepam

    SciTech Connect

    Wang, G.J.; Volkow, N.D.; Overall, J. |

    1996-10-01

    Changes in regional brain glucose metabolism in response to benzodiazepine agonists have been used as indicators of benzodiazepine-GABA receptor function. The purpose of this study was to assess the reproducibility of these responses. Sixteen healthy right-handed men underwent scanning with PET and [{sup 18}F]fluorodeoxyglucose (FDG) twice: before placebo and before lorazepam (30 {mu}g/kg). The same double FDG procedure was repeated 6-8 wk later on the men to assess test-retest reproducibility. The regional absolute brain metabolic values obtained during the second evaluation were significantly lower than those obtained from the first evaluation regardless of condition (p {le} 0.001). Lorazepam significantly and consistently decreased both whole-brain metabolism and the magnitude. The regional pattern of the changes were comparable for both studies (12.3% {plus_minus} 6.9% and 13.7% {plus_minus} 7.4%). Lorazepam effects were the largest in the thalamus (22.2% {plus_minus} 8.6% and 22.4% {plus_minus} 6.9%) and occipital cortex (19% {plus_minus} 8.9% and 21.8% {plus_minus} 8.9%). Relative metabolic measures were highly reproducible both for pharmacolgic and replication condition. This study measured the test-retest reproducibility in regional brain metabolic responses, and although the global and regional metabolic values were significantly lower for the repeated evaluation, the response to lorazepam was highly reproducible. 1613 refs., 3 figs., 3 tabs.

  19. Alzheimer's disease markers from structural MRI and FDG-PET brain images

    NASA Astrophysics Data System (ADS)

    Chincarini, Andrea; Bosco, Paolo; Gemme, Gianluca; Morbelli, Silvia; Arnaldi, Dario; Sensi, Francesco; Solano, Ilaria; Amoroso, Nicola; Tangaro, Sabina; Longo, Renata; Squarcia, Sandro; Nobili, Flavio

    2012-11-01

    Despite the widespread use of neuroimaging tools (morphological and functional) in the routine diagnostic of cerebral diseases, the information available by the end user -the clinician- remains largely limited to qualitative visual analysis. This restriction greatly reduces the diagnostic impact of neuroimaging in routine clinical practice and increases the risk of misdiagnosis. In this context, researches are focussing on the development of sophisticated automatic analyses able to extract clinically relevant information from the captured data. The identification of biological markers at early stages of Alzheimer's disease (AD) contributes to diagnostic accuracy and adds prognostic value. However, in spite of recent developments, results of structural and functional imaging studies on predicting conversion to AD are not uniform. We provide here an overview of analysis methods and approaches, discussing their contribution to clinical assessment.

  20. High intensity exercise decreases global brain glucose uptake in humans

    PubMed Central

    Kemppainen, Jukka; Aalto, Sargo; Fujimoto, Toshihiko; Kalliokoski, Kari K; Långsjö, Jaakko; Oikonen, Vesa; Rinne, Juha; Nuutila, Pirjo; Knuuti, Juhani

    2005-01-01

    Physiological activation increases glucose uptake locally in the brain. However, it is not known how high intensity exercise affects regional and global brain glucose uptake. The effect of exercise intensity and exercise capacity on brain glucose uptake was directly measured using positron emission tomography (PET) and [18F]fluoro-deoxy-glucose ([18F]FDG). Fourteen healthy, right-handed men were studied after 35 min of bicycle exercise at exercise intensities corresponding to 30, 55 and 75% of V˙O2max on three separate days. [18F]FDG was injected 10 min after the start of the exercise. Thereafter exercise was continued for another 25 min. PET scanning of the brain was conducted after completion of the exercise. Regional glucose metabolic rate (rGMR) decreased in all measured cortical regions as exercise intensity increased. The mean decrease between the highest and lowest exercise intensity was 32% globally in the brain (38.6 ± 4.6 versus 26.1 ± 5.0 μmol (100 g)−1 min−1, P < 0.001). Lactate availability during exercise tended to correlate negatively with the observed brain glucose uptake. In addition, the decrease in glucose uptake in the dorsal part of the anterior cingulate cortex (37% versus 20%, P < 0.05 between 30% and 75% of V˙O2max) was significantly more pronounced in subjects with higher exercise capacity. These results demonstrate that brain glucose uptake decreases with increase in exercise intensity. Therefore substrates other than glucose, most likely lactate, are utilized by the brain in order to compensate the increased energy needed to maintain neuronal activity during high intensity exercise. Moreover, it seems that exercise training could be related to adaptive metabolic changes locally in the frontal cortical regions. PMID:16037089

  1. [Technical limits of PET/CT with 18FDG in prostate cancer].

    PubMed

    von Mallek, D; Backhaus, B; Müller, S C; Matthies, A; Palmedo, H; Jaeger, U; Biersack, H-J; Reinhardt, M

    2006-05-01

    There is increasing evidence that (18)FDG-PET is not useful for the imaging of primary prostate cancer. The aim of this examination was to prove whether or not these poor results are due to technical deficiencies of the examination method like older image reconstruction techniques, extensive (18)FDG-tracer activity in the bladder or improper contrast staining of the rectum. We examined three patients with primary prostate cancer using a modern combined PET/CT system, continuous irrigation of the bladder and an air-inflated rectal balloon catheter. PET/CT images show an exact depiction of both the prostate and all surrounding anatomic structures but no enhanced uptake of radiotracer in the tumour. Therefore, the mentioned poor results of (18)FDG-PET seem not to be due to technical deficiencies.

  2. Growing applications of FDG PET-CT imaging in non-oncologic conditions

    PubMed Central

    Zhuang, Hongming; Codreanu, Ion

    2015-01-01

    Abstract As the number of clinical applications of 2-[fluorine 18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography/computed tomography (PET-CT) grows, familiarity with the conditions that can be diagnosed by this modality and when relevant pieces of additional information can be obtained becomes increasingly important for both requesting physicians and nuclear medicine physicians or radiologists who interpret the findings. Apart from its heavy use in clinical oncology, FDG PET-CT is widely used in a variety of non-oncologic conditions interconnecting to such disciplines as general internal medicine, infectious diseases, cardiology, neurology, surgery, traumatology, orthopedics, pediatrics, endocrinology, rheumatology, psychiatry, neuropsychology, and cognitive neuroscience. The aim of this review was to summarize the current evidence of FDG PET-CT applications in evaluating non-oncologic pathologies and the relevant information it can add to achieve a final diagnosis. PMID:26060443

  3. Detection of Diffuse Infiltrative Primary Hepatic Lymphoma on FDG PET-CT: Hallmarks of Hepatic Superscan.

    PubMed

    Mahajan, Sonia; Kalra, Shefali; Chawla, Madhavi; Dougall, Pankaj

    2016-01-01

    Primary hepatic lymphoma (PHL) is an extremely rare entity with scarce information in evidence-based literature. Few case reports have described the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) in the diagnosing and staging of PHL. We report the case of a 78-year-old man with PHL who initially presented with weight loss and nonspecific fatigue. FDG PET-CT proved to be a beneficial tool in arriving at the diagnosis of this patient with nonspecific clinical presentation and also in the staging of PHL. Physiological uptake of FDG in the liver can be a potential cause of misinterpretation in such cases. Hence, knowing the imaging hallmarks can increase the accuracy in PET image interpretation. PMID:27134567

  4. The Whole-Brain "Global" Signal from Resting State fMRI as a Potential Biomarker of Quantitative State Changes in Glucose Metabolism.

    PubMed

    Thompson, Garth J; Riedl, Valentin; Grimmer, Timo; Drzezga, Alexander; Herman, Peter; Hyder, Fahmeed

    2016-07-01

    The evolution of functional magnetic resonance imaging to resting state (R-fMRI) allows measurement of changes in brain networks attributed to state changes, such as in neuropsychiatric diseases versus healthy controls. Since these networks are observed by comparing normalized R-fMRI signals, it is difficult to determine the metabolic basis of such group differences. To investigate the metabolic basis of R-fMRI network differences within a normal range, eyes open versus eyes closed in healthy human subjects was used. R-fMRI was recorded simultaneously with fluoro-deoxyglucose positron emission tomography (FDG-PET). Higher baseline FDG was observed in the eyes open state. Variance-based metrics calculated from R-fMRI did not match the baseline shift in FDG. Functional connectivity density (FCD)-based metrics showed a shift similar to the baseline shift of FDG, however, this was lost if R-fMRI "nuisance signals" were regressed before FCD calculation. Average correlation with the mean R-fMRI signal across the whole brain, generally regarded as a "nuisance signal," also showed a shift similar to the baseline of FDG. Thus, despite lacking a baseline itself, changes in whole-brain correlation may reflect changes in baseline brain metabolism. Conversely, variance-based metrics may remain similar between states due to inherent region-to-region differences overwhelming the differences between normal physiological states. As most previous studies have excluded the spatial means of R-fMRI metrics from their analysis, this work presents the first evidence of a potential R-fMRI biomarker for baseline shifts in quantifiable metabolism between brain states. PMID:27029438

  5. Unexpected FDG-PET uptake in the gastrointestinal tract: Endoscopic and histopathological correlations

    PubMed Central

    Goldin, Eran; Mahamid, Mahmud; Koslowsky, Benjamin; Shteingart, Shimon; Dubner, Yael; Lalazar, Gadi; Wengrower, Dov

    2014-01-01

    AIM: To investigate the nature and significance of unexpected positron emission tomography with fluorodeoxyglucose (FDG-PET) uptake within the gastrointestinal tract (GIT). METHODS: Patients with unexpected FDG-PET findings in the GIT were evaluated. All patients had a previous confirmed malignancy, either solid or lymphoproliferative. The radiologic reports were performed by experienced radiologists with an exclusive PET expertise. Endoscopy, i.e., esophagogastroduodenoscopy (EGD) and colonoscopy, and histopathological evaluation of all findings was performed in all patients in accordance to the FDG-PET results. The findings from each of these modalities were compared to each other. Both clinically significant and insignificant findings were assessed. RESULTS: Seventy-two patients were endoscopically evaluated. Twenty-seven patients (37.5%) had primarily a lymphoproliferative tumor and 45 (62.5%) had solid tumors. In 50 patients (69.4%) the endoscopic examination revealed lesions in the same anatomical areas as the FDG-PET findings. Among these 50 patients, malignant and premalignant lesions i.e., adenomatous polyps were found in 16 (32%) and 9 (18%) patients, respectively. Inflammation was noted in an additional 20 patients (40%). Compared to primary solid tumors, a background of primary lymphoproliferative malignancy was more likely to reveal an additional primary malignancy (15.6% vs 33.3%, respectively, P < 0.01). EGD compared to colonoscopy, revealed altogether 11 (25.6%) new malignancies compared to 5 (17.2%), respectively, P = 0.12. No GIT clinically significant findings were overseen by the FDG-PET. CONCLUSION: Unexpected FDG uptake in the GIT is commonly encountered and may contain significant findings. Endoscopy evaluation is justified in order to detect these additional findings. PMID:24764676

  6. FDG-PET/CT for detection of the unknown primary head and neck tumor.

    PubMed

    Johansen, J; Petersen, H; Godballe, C; Loft, A; Grau, C

    2011-10-01

    The benefit of FDG-PET in addition to standard work-up for carcinoma of unknown primary (CUP) and metastatic neck lesions has been widely described. However, most studies have been of retrospective nature with large heterogeneities in terms of workup standards and patient selection leaving several questions to be answered regarding the real value of PET in CUP. We here present an overview of the literature with focus on the current evidence of FDG-PET in detecting a primary in CUP and discuss the rationale of PET/CT in the diagnostic armamentarium of CUP. PMID:22019707

  7. 18F-FDG PET/CT findings in voltage-gated potassium channel limbic encephalitis.

    PubMed

    Kamaleshwaran, Koramadai Karuppuswamy; Iyer, Rajesh Shankar; Antony, Joppy; Radhakrishnan, Edathuruthy Kalarickal; Shinto, Ajit

    2013-05-01

    Limbic encephalitis (LE) can be associated with cancer, viral infection, or be idiopathic. One such rare but treatable form is associated with voltage-gated potassium channel (VGKC) antibodies. Typical abnormalities are seen in FDG PET/CT. We report a 39-year-old female patient who presented with 3 months of progressive faciobrachial dystonic seizures and limbic encephalitis. Her serum and cerebrospinal fluid Lgi1 antibody titers were elevated. FDG PET/CT showed basal ganglial hypermetabolism and associated abnormalities. Serial MRI demonstrated atrophic changes predominantly involving the temporal lobes. She is on immunosuppressive therapy and shows clinical improvement with lowering of antibody titers.

  8. Segmental "misty mesentery" on FDG PET/CT: an uncommon manifestation of mesenteric lymphoma.

    PubMed

    Puranik, Ameya D; Purandare, Nilendu C; Agrawal, Archi; Shah, Sneha; Rangarajan, Venkatesh

    2014-01-01

    Mesenteric lymphomas are commonly seen as bulky hypermetabolic nodal masses on F-FDG PET/CT. Very rarely, these are seen as mesenteric haziness due to localized hyperattenuation of fat, known as "misty mesentery", which morphological imaging-wise has other differentials as well. We report a unique imaging finding of segmental misty mesentery with hypermetabolic mesenteric nodes on FDG PET/CT in a patient who was kept on observation due to inconclusive biopsy, which on follow-up imaging progressed to extensive lymphomatous involvement. Thus, in retrospect, this imaging feature on baseline PET/CT was diagnostic for mesenteric lymphoma. PMID:23797224

  9. Natural history of atherosclerotic disease progression as assessed by (18)F-FDG PET/CT.

    PubMed

    Hetterich, Holger; Rominger, Axel; Walter, Lisa; Habs, Maximilian; Volpers, Sarah; Hacker, Marcus; Reiser, Maximilian F; Bartenstein, Peter; Saam, Tobias

    2016-01-01

    The aim of this study was to assess the impact of cardiovascular risk factors and plaque inflammation on the progression of atherosclerosis as assessed by positron emission tomography/computed tomography (PET/CT) imaging with (18)F-radiolabled fluorodeoxyglucose ((18)F-FDG). This study was designed as a retrospective cohort study. Patients who received a (18)F-FDG PET/CT scan and follow-up scan 9-24 months later without systemic inflammation or steroid medication were eligible for the study. (18)F-FDG PET/CT included a full diagnostic contrast enhanced CT scan. Cardiovascular risk factors and medication were documented. Calcified plaque volume, lumen area and (18)F-FDG uptake, quantified by the target-to-background ratio (TBR), were measured in the carotid arteries, aorta and iliac arteries. Influence of cardiovascular risk factors and vessel wall inflammation on atherosclerotic disease progression was analyzed. Ninety-four patients underwent baseline and follow-up whole body (18)F-FDG PET/CT (mean follow-up time 14.5 ± 3.5 months). Annualized calcified plaque volume increased by 15.4 % (p < 0.0001), carotid and aortic lumen area decreased by 10.5 % (p < 0.0001) and 1.7 % (p = 0.045). There was no significant difference in (18)F-FDG uptake at baseline and follow-up (mean TBR 1.44 ± 0.18 vs. 1.42 ± 0.19, p = 0.18). Multiple linear regression analysis identified hypertension as an independent predictor for total, aortic and iliac calcified plaque volume progression (all p < 0.04). Carotid lumen reduction was predicted by hypercholesterolemia (p = 0.008) while aortic lumen reduction was associated with BMI and mean (18)F-FDG uptake (p ≤ 0.005). Furthermore we observed a dose response relationship between the number of cardiovascular risk factors and calcified plaque volume progression in the aorta (p = 0.03). Findings from this study provide data on the natural history of atherosclerotic disease burden in multiple vascular beds and emphasize the value of

  10. Imaging of Hepatic Ectopic Pregnancy by 18F-FDG PET/CT.

    PubMed

    Hao, Jingwen; Cheng, Zhen; Hu, Na; Xiao, Lizhi; Wang, Yunhua

    2016-09-01

    Hepatic ectopic pregnancy is an uncommon form of extrauterine pregnancy. A 31-year-old woman had acute abdominal pain and distention. Laboratory examination showed significantly increased serum β-human chorionic gonadotropin level. Both ultrasound and MRI identified a lesion located at the right lobe of the liver. FDG PET/CT was performed to determine whether the other causes of elevated β-human chorionic gonadotropin level, which showed an oval mass with mid peripherally increased FDG activity. After surgery, pathological results confirmed a diagnosis of hepatic ectopic pregnancy. PMID:27454601

  11. High liver FDG uptake on PET/CT in patient with lymphoma diagnosed with hereditary hemochromatosis.

    PubMed

    Infante, Jose R; Moreno, Manuel; Rayo, Juan I; Serrano, Justo; Dominguez, Maria L; Garcia, Lucia

    2015-06-01

    Hereditary hemochromatosis is an autosomal recessive disorder of iron metabolism resulting in toxic accumulation of iron in vital organs. We present a 64-year-old white man with non-Hodgkin lymphoma treated with high-dose chemotherapy and stem cell transplant that was subsequently diagnosed with hereditary hemochromatosis. F-FDG PET/CT was performed as routine follow-up and showed a pathological finding of homogeneous increased liver glucose metabolism. Increased FDG avidity in the liver suggested the presence of damage caused by hemochromatosis.

  12. Correlation between the Uptake of 18F-Fluorodeoxyglucose (18F-FDG) and the Expression of Proliferation-Associated Antigen Ki-67 in Cancer Patients: A Meta-Analysis

    PubMed Central

    Deng, Sheng-ming; Zhang, Wei; Zhang, Bin; Chen, Yin-yin; Li, Ji-hui; Wu, Yi-wei

    2015-01-01

    Objective To study the correlation between 18F-FDG uptake and cell proliferation in cancer patients by meta-analysis of published articles. Methods We searched PubMed (MEDLINE included), EMBASE, and Cochrane Database of Systematic Review, and selected research articles on the relationship between 18F-FDG uptake and Ki-67 expression (published between August 1, 1994-August 1, 2014), according to the literature inclusion and exclusion criteria. The publishing language was limited to English. The quality of included articles was evaluated according to the Quality Assessment of Diagnosis Accuracy Studies-2 (QUADAS-2). The correlation coefficient (r) was extracted from the included articles and processed by Fisher's r-to-z transformation. The combined correlation coefficient (r) and the 95% confidence interval (CI) were calculated with STATA 11.0 software under a random-effects model. Begg's test was used to analyze the existence of publication bias and draw funnel plot, and the sources of heterogeneity were explored by sensitivity and subgroup analyses. Results According to the inclusion and exclusion criteria, 79 articles were finally included, including 81 studies involving a total of 3242 patients. All the studies had a combined r of 0.44 (95% CI, 0.41-0.46), but with a significant heterogeneity (I2 = 80.9%, P<0.01). Subgroup analysis for different tumor types indicated that most subgroups showed a reduced heterogeneity. Malignant melanoma (n = 1) had the minimum correlation coefficient (-0.22) between 18F-FDG uptake and Ki-67 expression, while the thymic epithelial tumors (TETs; n = 2) showed the maximum correlation coefficient of 0.81. The analytical results confirmed that correlation between 18F-FDG uptake and Ki-67 expression was extremely significant in TETs, significant in gastrointestinal stromal tumors (GISTs), moderate in patients with lung, breast, bone and soft tissue, pancreatic, oral, thoracic, and uterine and ovarian cancers, average in brain

  13. A tripartite fusion, FaeG-FedF-LT(192)A2:B, of enterotoxigenic Escherichia coli (ETEC) elicits antibodies that neutralize cholera toxin, inhibit adherence of K88 (F4) and F18 fimbriae, and protect pigs against K88ac/heat-labile toxin infection.

    PubMed

    Ruan, Xiaosai; Liu, Mei; Casey, Thomas A; Zhang, Weiping

    2011-10-01

    Enterotoxigenic Escherichia coli (ETEC) strains expressing K88 (F4) or F18 fimbriae and heat-labile (LT) and/or heat-stable (ST) toxins are the major cause of diarrhea in young pigs. Effective vaccines inducing antiadhesin (anti-K88 and anti-F18) and antitoxin (anti-LT and anti-ST) immunity would provide broad protection to young pigs against ETEC. In this study, we genetically fused nucleotides coding for peptides from K88ac major subunit FaeG, F18 minor subunit FedF, and LT toxoid (LT(192)) A2 and B subunits for a tripartite adhesin-adhesin-toxoid fusion (FaeG-FedF-LT(192)A2:B). This fusion was used for immunizations in mice and pigs to assess the induction of antiadhesin and antitoxin antibodies. In addition, protection by the elicited antiadhesin and antitoxin antibodies against a porcine ETEC strain was evaluated in a gnotobiotic piglet challenge model. The data showed that this FaeG-FedF-LT(192)A2:B fusion elicited anti-K88, anti-F18, and anti-LT antibodies in immunized mice and pigs. In addition, the anti-porcine antibodies elicited neutralized cholera toxin and inhibited adherence against both K88 and F18 fimbriae. Moreover, immunized piglets were protected when challenged with ETEC strain 30302 (K88ac/LT/STb) and did not develop clinical disease. In contrast, all control nonvaccinated piglets developed severe diarrhea and dehydration after being challenged with the same ETEC strain. This study clearly demonstrated that this FaeG-FedF-LT(192)A2:B fusion antigen elicited antibodies that neutralized LT toxin and inhibited the adherence of K88 and F18 fimbrial E. coli strains and that this fusion could serve as an antigen for vaccines against porcine ETEC diarrhea. In addition, the adhesin-toxoid fusion approach used in this study may provide important information for developing effective vaccines against human ETEC diarrhea. PMID:21813665

  14. Metabolic brain imaging correlated with clinical features of brain tumors

    SciTech Connect

    Alavi, J.; Alavi, A.; Dann, R.; Kushner, M.; Chawluk, J.; Powlis, W.; Reivich, M.

    1985-05-01

    Nineteen adults with brain tumors have been studied with positron emission tomography utilizing FDG. Fourteen had biopsy proven cerebral malignant glioma, one each had meningioma, hemangiopericytoma, primitive neuroectodermal tumor (PNET), two had unbiopsied lesions, and one patient had an area of biopsy proven radiation necrosis. Three different patterns of glucose metabolism are observed: marked increase in metabolism at the site of the known tumor in (10 high grade gliomas and the PNET), lower than normal metabolism at the tumor (in 1 grade II glioma, 3 grade III gliomas, 2 unbiopsied low density nonenhancing lesions, and the meningioma), no abnormality (1 enhancing glioma, the hemangiopericytoma and the radiation necrosis.) The metabolic rate of the tumor or the surrounding brain did not appear to be correlated with the history of previous irradiation or chemotherapy. Decreased metabolism was frequently observed in the rest of the affected hemisphere and in the contralateral cerebellum. Tumors of high grade or with enhancing CT characteristics were more likely to show increased metabolism. Among the patients with proven gliomas, survival after PETT scan tended to be longer for those with low metabolic activity tumors than for those with highly active tumors. The authors conclude that PETT may help to predict the malignant potential of tumors, and may add useful clinical information to the CT scan.

  15. 18F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma

    PubMed Central

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on 18F-FDG PET/CT mimicked malignant lymphoma. Follow-up 18F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting 18F-FDG PET/CT scans. PMID:27187482

  16. (18)F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma.

    PubMed

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on (18)F-FDG PET/CT mimicked malignant lymphoma. Follow-up (18)F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting (18)F-FDG PET/CT scans. PMID:27187482

  17. Radiation-induced DNA damage and the relative biological effectiveness of 18F-FDG in wild-type mice

    DOE PAGES

    Taylor, Kristina; Lemon, Jennifer A.; Boreham, Douglas R.

    2014-05-28

    Clinically, the most commonly used positron emission tomography (PET) radiotracer is the glucose analog 2-[18F] fluoro-2-deoxy-d-glucose (18F-FDG), however little research has been conducted on the biological effects of 18F-FDG injections. The induction and repair of DNA damage and the relative biological effectiveness (RBE) of radiation from 18F-FDG relative to 662 keV γ-rays were investigated. The study also assessed whether low-dose radiation exposure from 18F-FDG was capable of inducing an adaptive response. DNA damage to the bone marrow erythroblast population was measured using micronucleus formation and lymphocyte γH2A.X levels. To test the RBE of 18F-FDG, mice were injected with a rangemore » of activities of 18F-FDG (0–14.80 MBq) or irradiated with Cs-137 γ-rays (0–100 mGy). The adaptive response was investigated 24 h after the 18F-FDG injection by 1 Gy in vivo challenge doses for micronucleated reticulocyte (MN-RET) formation or 1, 2 and 4 Gy in vitro challenges doses for γH2A.X formation. A significant increase in MN-RET formation above controls occurred following injection activities of 3.70, 7.40 or 14.80 MBq (P < 0.001) which correspond to bone marrow doses of ~35, 75 and 150 mGy, respectively. Per unit dose, the Cs-137 radiation exposure induced significantly more damage than the 18F-FDG injections (RBE = 0.79 ± 0.04). A 20% reduction in γH2A.X fluorescence was observed in mice injected with a prior adapting low dose of 14.80 MBq 18F-FDG relative to controls (P < 0.019). A 0.74 MBq 18F-FDG injection, which gives mice a dose approximately equal to a typical human PET scan, did not cause a significant increase in DNA damage nor did it generate an adaptive response. Typical 18F-FDG injection activities used in small animal imaging (14.80 MBq) resulted in a decrease in DNA damage, as measured by γH2A.X formation, below spontaneous levels observed in control mice. Lastly, the 18F-FDG RBE was <1.0, indicating that the mixed radiation quality

  18. 18F-FDG PET imaging in a patient with late omental infarction after treatment of pancreatic adenocarcinoma.

    PubMed

    Chassagnon, Guillaume; Metrard, Gilles; Besse, Hélène; Gauvain, Sabine

    2014-06-01

    We report a case of late omental infarction visualized by F-FDG PET/CT during follow-up for pancreatic adenocarcinoma. The 65-year-old patient was referred for imaging 8 months after pancreaticoduodenectomy and 2 months after completion of a course of chemotherapy. PET/CT showed an FDG-avid omental lesion that suggested peritoneal carcinomatosis. The appearance and evolution at follow-up studies confirmed the diagnosis of omental infarction, a rare complication of pancreatic surgery. This case revealed the possibility of late FDG uptake in omental infarction.

  19. Historic images in nuclear medicine: 1976: the first issue of clinical nuclear medicine and the first human FDG study.

    PubMed

    Hess, Søren; Høilund-Carlsen, Poul Flemming; Alavi, Abass

    2014-08-01

    In 1976, 2 major molecular imaging events coincidentally took place: Clinical Nuclear Medicine was first published in June, and in August researchers at the Hospital of the University of Pennsylvania created the first images in humans with F-FDG. FDG was initially developed as part of an evolution set in motion by fundamental research studies with positron-emitting tracers in the 1950s by Michel Ter-Pegossian and coworkers at the Washington University. Today, Clinical Nuclear Medicine is a valued scientific contributor to the molecular imaging community, and FDG PET is considered the backbone of this evolving and exciting discipline.

  20. A solitary fibrous tumor arising in the parapharyngeal space, with MRI and FDG-PET findings.

    PubMed

    Wakisaka, Naohiro; Kondo, Satoru; Murono, Shigeyuki; Minato, Hiroshi; Furukawa, Mitsuru; Yoshizaki, Tomokazu

    2009-06-01

    We present the imaging and pathological features of a 38-year-old man in whom a large parapharyngeal solitary fibrous tumor (SFT) on the left side was found. On MRI, the tumor showed a nodule-in-nodule appearance. The inner nodule revealed high signal intensities both on T1- and T2-weighted MR images. The entire tumor showed heterogeneous enhancement on gadolinium-enhanced T1-weighted images. (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) identified heterogeneous radiotracer uptake of FDG in the inner nodule of the tumor. Histologic examinations revealed an admixture of growth patterns, including a "patternless pattern" and "haemangiopericytoma-like pattern". The tumor was positive for CD34. Imaging features of SFT arising in the parapharyngeal space are discussed with a review of literatures. This is the first report of FDG-PET finding of SFT arising in the head and neck. More cases are needed to achieve diagnostic significance from FDG-PET findings of parapharyngeal SFTs.

  1. A rare case of mature teratoma. Has FDG PET/CT a role to play?

    PubMed

    Mohapatra, Tushar; Arora, Abhishek; Srikant, K; Snehalata; Kumar, Nandish

    2011-04-01

    Authors describe a very rare case of mature teratoma with malignant transformation, preoperatively suggested by FDG PET/CT study. So the role of CT component in elucidating three embryonal components and hypermetabolism evident on PET part suggesting possible malignant transformation makes PET/CT a valuable modality in evaluation of these rare tumors.

  2. Different Scoring Methods of FDG PET/CT in Giant Cell Arteritis

    PubMed Central

    Stellingwerff, Menno D.; Brouwer, Elisabeth; Lensen, Karel-Jan D.F.; Rutgers, Abraham; Arends, Suzanne; van der Geest, Kornelis S.M.; Glaudemans, Andor W.J.M.; Slart, Riemer H.J.A.

    2015-01-01

    Abstract Giant cell arteritis (GCA) is the most frequent form of vasculitis in persons older than 50 years. Cranial and systemic large vessels can be involved. [18F] fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is increasingly used to diagnose inflammation of the large arteries in GCA. Unfortunately, no consensus exists on the preferred scoring method. In the present study, we aim to define the optimal FDG PET/CT scoring method for GCA diagnosis using temporal artery biopsy and clinical diagnosis as the reference method. FDG PET/CT scans of GCA patients (12 glucocorticoid-naive, 6 on glucocorticoid treatment) and 3 control groups (inflammatory, atherosclerotic, and normal controls) were evaluated. We compared 2 qualitative visual methods (i.e. (1a) first impression and (1b) vascular uptake versus liver uptake) and 4 semiquantitative methods ((2a) SUVmax aorta, (2b) SUVmax aorta-to-liver ratio, (2c) SUVmax aorta-to-superior-caval-vein ratio, and (2d) SUVmax aorta-to-inferior-caval-vein ratio). FDG uptake pattern (diffuse or focal) and presence of arterial calcifications were also scored. Diagnostic accuracy of the visual method vascular versus liver uptake (1b) was highest when the cut-off point “vascular uptake higher than liver uptake” (sensitivity 83%, specificity 91%) was used. Sensitivity increased to 92% when patients on glucocorticoids were excluded from the analysis. Regarding the semiquantitative methods, the aorta-to-liver ratio (2b) with a cutoff of 1.03 had the highest diagnostic accuracy, with a sensitivity and specificity of 69% and 92%, respectively. Sensitivity increased to 90% when patients on glucocorticoids were excluded. The number of vascular segments with diffuse FDG uptake pattern was significantly higher in GCA patients without glucocorticoid use compared with all control patient groups. CRP was not significantly different between positive and negative FDG PET scans in the GCA group. Visual vascular

  3. [18F]FDG Accumulation in Early Coronary Atherosclerotic Lesions in Pigs

    PubMed Central

    Tarkia, Miikka; Saraste, Antti; Stark, Christoffer; Vähäsilta, Tommi; Savunen, Timo; Strandberg, Marjatta; Saunavaara, Virva; Tolvanen, Tuula; Teuho, Jarmo; Teräs, Mika; Metsälä, Olli; Rinne, Petteri; Heinonen, Ilkka; Savisto, Nina; Pietilä, Mikko; Saukko, Pekka; Roivainen, Anne; Knuuti, Juhani

    2015-01-01

    Objective Inflammation is an important contributor to atherosclerosis progression. A glucose analogue 18F-fluorodeoxyglucose ([18F]FDG) has been used to detect atherosclerotic inflammation. However, it is not known to what extent [18F]FDG is taken up in different stages of atherosclerosis. We aimed to study the uptake of [18F]FDG to various stages of coronary plaques in a pig model. Methods First, diabetes was caused by streptozotocin injections (50 mg/kg for 3 days) in farm pigs (n = 10). After 6 months on high-fat diet, pigs underwent dual-gated cardiac PET/CT to measure [18F]FDG uptake in coronary arteries. Coronary segments (n = 33) were harvested for ex vivo measurement of radioactivity and autoradiography (ARG). Results Intimal thickening was observed in 16 segments and atheroma type plaques in 10 segments. Compared with the normal vessel wall, ARG showed 1.7±0.7 times higher [18F]FDG accumulation in the intimal thickening and 4.1±2.3 times higher in the atheromas (P = 0.004 and P = 0.003, respectively). Ex vivo mean vessel-to-blood ratio was higher in segments with atheroma than those without atherosclerosis (2.6±1.2 vs. 1.3±0.7, P = 0.04). In vivo PET imaging showed the highest target-to-background ratio (TBR) of 2.7. However, maximum TBR was not significantly different in segments without atherosclerosis (1.1±0.5) and either intimal thickening (1.2±0.4, P = 1.0) or atheroma (1.6±0.6, P = 0.4). Conclusions We found increased uptake of [18F]FDG in coronary atherosclerotic lesions in a pig model. However, uptake in these early stage lesions was not detectable with in vivo PET imaging. Further studies are needed to clarify whether visible [18F]FDG uptake in coronary arteries represents more advanced, highly inflamed plaques. PMID:26120829

  4. Risk-Adapted Dose-Dense Immunochemotherapy Determined by Interim FDG-PET in Advanced-Stage Diffuse Large B-Cell Lymphoma

    PubMed Central

    Moskowitz, Craig H.; Schöder, Heiko; Teruya-Feldstein, Julie; Sima, Camelia; Iasonos, Alexia; Portlock, Carol S.; Straus, David; Noy, Ariela; Palomba, Maria L.; O'Connor, Owen A.; Horwitz, Steven; Weaver, Sarah A.; Meikle, Jessica L.; Filippa, Daniel A.; Caravelli, James F.; Hamlin, Paul A.; Zelenetz, Andrew D.

    2010-01-01

    Purpose In studies of diffuse large B-cell lymphoma, positron emission tomography with [18F]fluorodeoxyglucose (FDG-PET) performed after two to four cycles of chemotherapy has demonstrated prognostic significance. However, some patients treated with immunochemotherapy experience a favorable long-term outcome despite a positive interim FDG-PET scan. To clarify the significance of interim FDG-PET scans, we prospectively studied interim FDG-positive disease within a risk-adapted sequential immunochemotherapy program. Patients and Methods From March 2002 to November 2006, 98 patients at Memorial Sloan-Kettering Cancer Center received induction therapy with four cycles of accelerated R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by an interim FDG-PET scan. If the FDG-PET scan was negative, patients received three cycles of ICE (ifosfamide, carboplatin, and etoposide) consolidation therapy. If residual FDG-positive disease was seen, patients underwent biopsy; if the biopsy was negative, they also received three cycles of ICE. Patients with a positive biopsy received ICE followed by autologous stem-cell transplantation. Results At a median follow-up of 44 months, overall and progression-free survival were 90% and 79%, respectively. Ninety-seven patients underwent interim FDG-PET scans; 59 had a negative scan, 51 of whom are progression free. Thirty-eight patients with FDG-PET–positive disease underwent repeat biopsy; 33 were negative, and 26 remain progression free after ICE consolidation therapy. Progression-free survival of interim FDG-PET–positive/biopsy-negative patients was identical to that in patients with a negative interim FDG-PET scan (P = .27). Conclusion Interim or post-treatment FDG-PET evaluation did not predict outcome with this dose-dense, sequential immunochemotherapy program. Outside of a clinical trial, we recommend biopsy confirmation of an abnormal interim FDG-PET scan before changing therapy. PMID

  5. Study of an image-derived SUV and a modified SUV using mouse FDG-PET

    PubMed Central

    Zheng, Xiujuan; Yu, Chin-Lung; Sha, Wei; Radu, Caius; Huang, Sung-Cheng; Feng, Dagan

    2010-01-01

    Introduction Standard uptake value (SUV) is calculated without consideration of the differences in plasma FDG clearance. Its variability can be affected by changes of the amount of excreted FDG by renal function. Moreover, the estimation of SUV is quite sensitive to errors in the measurements of body weight and injected dose. This study aims to develop an image-based method to obtain an image-derived SUV (iSUV) and a modified SUV (mSUV) to overcome these problems. Methods 31 tumor-planted SCID mice were scanned in microPET at ~60min post FDG injection, and then scanned in microCT. Using image-based method, the body weight and injected dose were derived from the microPET/CT images to calculate iSUV. The volumes and the total activities of FDG within the bladder and the whole-body were also obtained to calculate mSUV. For the selected targets, the iSUVs and mSUVs were compared against their corresponding SUVs. Results Compared with SUV factor (injected dose/body weight), iSUV factor had an average percentage error of −0.7%. The linear regressions between SUV and iSUV had a slope of 0.99 with correlation coefficient of 0.95. Compared with SUV and iSUV, CV% of mSUV decreased while the tumor-to-background separation of mSUV increased. Conclusions Using this image-based method, the iSUV can replace SUV when the actual measurements were missing or unreliable. The mSUV can reduce the inter-subject variability and enhance the tumor-to-background separation in mouse FDG-PET studies. PMID:21492784

  6. Use of FDG-PET in differentiating benign from malignant compression fractures

    PubMed Central

    Essary, Brendan; Torriani, Martin; Ouellette, Hugue A.; Palmer, William E.

    2008-01-01

    Objective The objective was to evaluate the use of fluorodeoxyglucose positron emission tomography (FDG-PET) in differentiating benign from malignant compression fractures. Patients and methods In a retrospective analysis, we identified 33 patients with 43 compression fractures who underwent FDG-PET. On FDG-PET the uptake pattern was recorded qualitatively and semiquantitatively and fractures were categorized as benign or malignant. Standardized uptake values (SUV) were obtained. MRI, CT, and biopsy results as well as clinical follow-up for 1–3 years served as standards of reference. The Student’s t test was used to determine whether there was a statistically significant difference between the SUV for benign and malignant compression fractures. Results There were 14 malignant and 29 benign compression fractures, including 5 acute benign fractures. On FDG-PET, 5 benign fractures were falsely classified as malignant (false-positive). Three of these patients underwent prior treatment with bone marrow-stimulating agents. There were two false-negative results. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FDG-PET in differentiating benign from malignant compression fractures were 86%, 83%, 84%, 71%, and 92% respectively. The difference between SUV values of benign and malignant fractures was statistically significant (1.9 ± 0.97 for benign and 3.9 ± 1.52 for malignant fractures, p < 0.001). SUV of benign acute and chronic fractures were not statistically significant. Conclusion Fluorodeoxyglucose positron emission tomography is useful in differentiating benign from malignant compression fractures. Therapy with bone marrow-stimulating agents can mimic malignant involvement. PMID:18278491

  7. Quantitative Assessment of Heterogeneity in Tumor Metabolism Using FDG-PET

    SciTech Connect

    Vriens, Dennis; Disselhorst, Jonathan A.; Oyen, Wim J.G.; Geus-Oei, Lioe-Fee de; Visser, Eric P.

    2012-04-01

    Purpose: [{sup 18}F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) images are usually quantitatively analyzed in 'whole-tumor' volumes of interest. Also parameters determined with dynamic PET acquisitions, such as the Patlak glucose metabolic rate (MR{sub glc}) and pharmacokinetic rate constants of two-tissue compartment modeling, are most often derived per lesion. We propose segmentation of tumors to determine tumor heterogeneity, potentially useful for dose-painting in radiotherapy and elucidating mechanisms of FDG uptake. Methods and Materials: In 41 patients with 104 lesions, dynamic FDG-PET was performed. On MR{sub glc} images, tumors were segmented in quartiles of background subtracted maximum MR{sub glc} (0%-25%, 25%-50%, 50%-75%, and 75%-100%). Pharmacokinetic analysis was performed using an irreversible two-tissue compartment model in the three segments with highest MR{sub glc} to determine the rate constants of FDG metabolism. Results: From the highest to the lowest quartile, significant decreases of uptake (K{sub 1}), washout (k{sub 2}), and phosphorylation (k{sub 3}) rate constants were seen with significant increases in tissue blood volume fraction (V{sub b}). Conclusions: Tumor regions with highest MR{sub glc} are characterized by high cellular uptake and phosphorylation rate constants with relatively low blood volume fractions. In regions with less metabolic activity, the blood volume fraction increases and cellular uptake, washout, and phosphorylation rate constants decrease. These results support the hypothesis that regional tumor glucose phosphorylation rate is not dependent on the transport of nutrients (i.e., FDG) to the tumor.

  8. Patient-specific FDG dosimetry for adult males, adult females, and very low birth weight infants

    NASA Astrophysics Data System (ADS)

    Niven, Erin

    Fluorodeoxyglucose is the most commonly used radiopharmaceutical in Positron Emission Tomography, with applications in neurology, cardiology, and oncology. Despite its routine use worldwide, the radiation absorbed dose estimates from FDG have been based primarily on data obtained from two dogs studied in 1977 and 11 adults (most likely males) studied in 1982. In addition, the dose estimates calculated for FDG have been centered on the adult male, with little or no mention of variations in the dose estimates due to sex, age, height, weight, nationality, diet, or pathological condition. Through an extensive investigation into the Medical Internal Radiation Dose schema for calculating absorbed doses, I have developed a simple patient-specific equation; this equation incorporates the parameters necessary for alterations to the mathematical values of the human model to produce an estimate more representative of the individual under consideration. I have used this method to determine the range of absorbed doses to FDG from the collection of a large quantity of biological data obtained in adult males, adult females, and very low birth weight infants. Therefore, a more accurate quantification of the dose to humans from FDG has been completed. My results show that per unit administered activity, the absorbed dose from FDG is higher for infants compared to adults, and the dose for adult women is higher than for adult men. Given an injected activity of approximately 3.7 MBq kg-1, the doses for adult men, adult women, and full-term newborns would be on the order of 5.5, 7.1, and 2.8 mSv, respectively. These absorbed doses are comparable to the doses received from other nuclear medicine procedures.

  9. Brain Power.

    ERIC Educational Resources Information Center

    Albrecht, Karl

    2002-01-01

    Reviews significant findings of recent brain research, including the concept of five minds: automatic, subconscious, practical, creative, and spiritual. Suggests approaches to training the brain that are related to this hierarchy of thinking. (JOW)

  10. Brain Basics

    MedlinePlus

    ... have been linked to many mental disorders, including autism , obsessive compulsive disorder (OCD) , schizophrenia , and depression . Brain ... studies show that brain growth in children with autism appears to peak early. And as they grow ...

  11. Brain components

    MedlinePlus

    ... 3 major components of the brain are the cerebrum, cerebellum, and brain stem. The cerebrum is divided into left and right hemispheres, each ... gray matter) is the outside portion of the cerebrum and provides us with functions associated with conscious ...

  12. Brain Diseases

    MedlinePlus

    The brain is the control center of the body. It controls thoughts, memory, speech, and movement. It regulates the function of many organs. When the brain is healthy, it works quickly and automatically. However, ...

  13. Brain abscess

    MedlinePlus

    Tunkel AR. Brain abscess. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice ... Philadelphia, PA: Elsevier Saunders; 2015:chap 92. Tunkel AR, Scheld WM. Brain abscess. In: Winn HR, ed. ...

  14. Dynamic FDG PET/CT imaging with diuresis demonstrates an enterovesical fistula in a lymphoma patient with repeated colon diverticulitis.

    PubMed

    Kao, Pan-Fu; Ting, Wen-Chien; Hsiao, Pei-Ching; Kao, Yu-Lin; Chang, Pai-Jung; Lee, Jong-Kang

    2013-04-01

    A 43-year-old male patient with follicular B-cell lymphoma was referred for a FDG PET/CT scan due to severe left lower abdominal pain to rule out recurrent cancer. These FDG PET/CT images and previous FDG PET/CT images 5 months ago both revealed an air bubble in the urinary bladder on the CT images. He had a recurrent urinary tract infection history for 6 months. A list-mode dynamic data acquisition with diuresis intravenous injection revealed linear FDG activity extending from the upper-left portion of the bladder to a soft tissue mass in the lower-left pelvic region. An enterovesical fistula was confirmed by surgery.

  15. Recurrent tumor vs radiation effects after Gamma Knife radiosurgery of intracerebral metastases: Diagnosis with PET-FDG

    SciTech Connect

    Mogard, J.; Kihlstroem, L.; Ericson, K. |

    1994-03-01

    Our objective was to differentiate radiation effects from tumor progression in metastases stereotaxically irradiated with the multicobalt unit (Gamma Knife). Eleven patients with stereotaxically irradiated cerebral metastases were examined with PET using [{sup 18}F]fluorodeoxyglucose (FDG) to differentiate recurrent tumor from radiation effects. Six patients had increased uptake of FDG, and clinical, radiological, and pathological findings confirmed the diagnosis of recurrent metastases. These patients had an unfavorable prognosis and were all dead within 54 weeks after radiosurgery. Five patients had lesions without an increased accumulation of FDG. Four of these patients were alive after a total follow-up of 1.7 years, while one patient died of a peptic ulcer 56 weeks after radiosurgery. Positron emission tomography with FDG was of obvious prognostic value in this small series of patients and was clearly superior to CT and MR in the distinction between tumor recurrence and radiation effects (verified necrosis in one case). 24 refs., 2 figs., 2 tabs.

  16. False Suggestion of Malignant Transformation of Benign Bone Tumor by 18F-FDG PET/CT: A Potential Pitfall.

    PubMed

    Chen, Yu-Ren; Kuo, Yu-Cheng; Hsu, Cheng-Nan; Hsieh, Te-Chun; Kao, Chia-Hung

    2016-10-01

    A 68-year-old man underwent serial F-FDG PET/CT scan follow-up for lung cancer. Then 5.5 years after the initial F-FDG PET/CT scan, the presumed benign bone tumor in the left clavicle showed markedly increased FDG uptake during follow-up; in contrast, the Tc-MDP bone scan paradoxically exhibited no apparent interval change since last bone scan 5.5 years earlier. He underwent a CT-guided biopsy, and the pathological diagnosis was benign fibrous histiocytoma. The result was consistent with the lack of progression in Tc-MDP bone scan, whereas the F-FDG PET/CT scan gave a false-positive impression of malignant transformation. PMID:27556801

  17. Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography

    SciTech Connect

    Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

    1985-05-01

    The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions.

  18. Effects of acupuncture at HT7 on glucose metabolism in a rat model of Alzheimer's disease: an 18F-FDG-PET study

    PubMed Central

    Lai, Xinsheng; Ren, Jie; Lu, Yangjia; Cui, Shaoyang; Chen, Junqi; Huang, Yong; Tang, Chunzhi; Shan, Baoci; Nie, Bingbing

    2016-01-01

    Objective To explore the effects of acupuncture at HT7 on different cerebral regions in a rat model of Alzheimer's disease (AD) with the application of 18F-2-fluoro-deoxy-D-glucose positron emission tomography (FDG-PET). Methods Sixty Wistar rats were included after undergoing a Y-maze electric sensitivity test. Ten rats were used as a healthy control group. The remaining 50 rats were injected stereotaxically with ibotenic acid into the right nucleus basalis magnocellularis and injected intraperitoneally with D-galactose. AD was successfully modelled in 36 rats, which were randomly divided into three groups (n=12 each): the AD group, which remained untreated; the AD+HT7 group, which received 20 sessions of acupuncture at HT7 over 1 month; and the AD+Sham group, which received acupuncture at a distant non-acupuncture point. Total reaction time (TRT) was measured by Y-maze and 18F-FDG-PET scans were conducted on day 1 and 30. PET images were processed with Statistical Parametric Mapping 8.0. Results Pre-treatment, TRT was greater in all AD groups versus controls (mean±SD 24.10±2.48 vs 41.34±5.00 s). Post-treatment, TRT was shortened in AD+HT7 versus AD+Sham and AD groups (p<0.0001, two-way analysis of variance). Glucose metabolic activity in the hippocampus, thalamus, hypothalamus, frontal lobe, and temporal lobe was decreased in AD rats compared with healthy controls and relatively elevated after HT7 acupuncture. Compared with sham acupuncture, HT7 needling had a greater positive influence on brain glucose metabolism. Conclusions Needling at HT7 can improve memory ability and cerebral glucose metabolic activity of the hippocampus, thalamus, hypothalamus, and frontal/temporal lobes in an AD rat model. PMID:26654890

  19. Brain Aneurysm

    MedlinePlus

    A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they ... often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, ...

  20. Stereotactic PET atlas of the human brain: Aid for visual interpretation of functional brain images

    SciTech Connect

    Minoshima, S.; Koeppe, R.A.; Frey, A.; Ishihara, M.; Kuhl, D.E.

    1994-06-01

    In the routine analysis of functional brain images obtained by PET, subjective visual interpretation is often used for anatomic localization. To enhance the accuracy and consistency of the anatomic interpretation, a PET stereotactic atlas and localization approach was designed for functional brain images. The PET atlas was constructed from a high-resolution [{sup 18}F]fluorodeoxyglucose (FDG) image set of a normal volunteer (a 41-yr-ld woman). The image set was reoriented stereotactically, according to the intercommissural (anterior and posterior commissures) line and transformed to the standard stereotactic atlas coordinates. Cerebral structures were annotated on the transaxial planes using a proportional grid system and surface-rendered images. The stereotactic localization technique was applied to image sets from patients with Alzheimer`s disease, and areas of functional alteration were localized visually by referring to the PET atlas. Major brain structures were identified on both transaxial planes and surface-rendered images. In the stereotactic system, anatomic correspondence between the PET atlas and stereotactically reoriented individual image sets of patients with Alzheimer`s disease facilitated both indirect and direct localization of the cerebral structures. Because rapid stereotactic alignment methods for PET images are now available for routine use, the PET atlas will serve as an aid for visual interpretation of functional brain images in the stereotactic system. Widespread application of stereotactic localization may be used in functional brain images, not only in the research setting, but also in routine clinical situations. 41 refs., 3 figs.

  1. Diagnostic FDG and FDOPA positron emission tomography scans distinguish the genomic type and treatment outcome of neuroblastoma

    PubMed Central

    Chang, Hsiu-Hao; Lu, Ching-Chu; Lin, Dong-Tsamn; Jou, Shiann-Tarng; Yang, Yung-Li; Lee, Ya-Ling; Huang, Shiu-Feng; Jeng, Yung-Ming; Lee, Hsinyu; Miser, James S.; Lin, Kai-Hsin; Liao, Yung-Feng; Hsu, Wen-Ming; Tzen, Kai-Yuan

    2016-01-01

    Neuroblastoma (NB) is a heterogeneous childhood cancer that requires multiple imaging modalities for accurate staging and surveillances. This study aims to investigate the utility of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) and 18F-fluoro-dihydroxyphenylalanine (FDOPA) in determining the prognosis of NB. During 2007–2014, forty-two NB patients (male:female, 28:14; median age, 2.0 years) undergoing paired FDG and FDOPA PET scans at diagnosis were evaluated for the maximum standardized uptake value (SUVmax) of FDG or FDOPA by the primary tumor. Patients with older age, advanced stages, or MYCN amplification showed higher FDG and lower FDOPA SUVmax (all P < 0.02). Receiver operating characteristics analysis identified FDG SUVmax≥ 3.31 and FDOPA SUVmax < 4.12 as an ultra-high-risk feature (PET-UHR) that distinguished the most unfavorable genomic types, i.e. segmental chromosomal alterations and/or MYCN amplification, at a sensitivity of 81.3% (54.4%–96.0%) and a specificity of 93.3% (68.1%–99.8%). Considering with age, stage, MYCN status, and anatomical image-defined risk factor, PET-UHR was an independent predictor of inferior event-free survival (multivariate hazard ratio, 4.9 [1.9–30.1]; P = 0.012). Meanwhile, the ratio between FDG and FDOPA SUVmax (G:D) correlated positively with HK2 (Spearman's ρ = 0.86, P < 0.0001) and negatively with DDC (ρ = −0.58, P = 0.02) gene expression levels, which might suggest higher glycolytic activity and less catecholaminergic differentiation in NB tumors taking up higher FDG and lower FDOPA. In conclusion, the intensity of FDG and FDOPA uptake on diagnostic PET scans may predict the tumor behavior and complement the current risk stratification systems of NB. PMID:26959748

  2. Brentuximab vedotin administered to platinum-refractory, transplant-naïve Hodgkin lymphoma patients can increase the proportion achieving FDG PET negative status.

    PubMed

    Onishi, Maika; Graf, Solomon A; Holmberg, Leona; Behnia, Sanaz; Shustov, Andrei R; Schiavo, Karen; Philip, Mary; Libby, Edward N; Cassaday, Ryan D; Pagel, John M; Roden, Jennifer E; Maloney, David G; Green, Damian J; Till, Brian G; Press, Oliver W; Smith, Stephen D; Gopal, Ajay K

    2015-12-01

    Normalization of fluorodeoxyglucose positron emission tomography (FDG PET) imaging prior to high-dose therapy and autologous stem cell transplantation (ASCT) improves outcomes in relapsed and refractory (RR) Hodgkin lymphoma (HL), but many patients refractory to platinum-based salvage regimens are unable to achieve this goal. We therefore investigated whether brentuximab vedotin (BV) could normalize FDG PET in platinum-refractory HL prior to ASCT. Fifteen consecutive patients with RR HL and FDG PET positive disease after platinum-based salvage therapy were treated with a median of 4 cycles of BV. Normalization of FDG PET (Deauville ≤2) occurred in 8/15 (53%) patients but was only observed in patients that had achieved partial remission or stable disease after platinum-based salvage therapy. All patients eventually proceeded to ASCT, regardless of FDG PET status. Our data suggest that BV can normalize FDG PET in a subset of patients with platinum-refractory HL prior to ASCT.

  3. Is (18)F-FDG PET really a promising marker for clinically relevant atherosclerosis?

    PubMed

    Brammen, Lindsay; Palumbo, Barbara; Lupattelli, Graziana; Sinzinger, Helmut

    2014-01-01

    Bural et al (2013), retrospectively investigated 143 subjects who received whole body fluorine-18-fluorodeoxyglucose- positron emission tomography ((18)F-FDG-PET) imaging for the assessment of non-cardiovascular diseases. They reported an increase of (18)F-FDG-positive lesions in various aortic segments, which increased with age, and were more pronounced in subjects being aged below 50 years as compared to those above 50. Bural et al also found the highest segmental (18)F-FDG-uptake in the descending thoracic aorta, but not in the abdominal aorta, where the majority of the most severe atherosclerotic lesions essentially appear. In addition, they did not appreciate any significant gender difference. Despite the severe limitation that no correlation to vascular disease, risk factors, or any clinical parameter was available, this report again raises the question as to what positive (18)F-FDG imaging really reflects and whether it will ever reach the great expectations. Conventional radiotracers revealed an excellent experimental correlation, as well as morphology. Uptake ratios of symptomatic lesion vs. contralateral unaffected side were comparable between (111)In-platelets, (123)I-LDL and (18)FFDG. There was also a mass strategic correlation, but no individual prediction of events at all. Due to better statistics, image quality and solution PET imaging of atherosclerosis holds great promise. However, correlations between various tracers and vascular wall characteristics (and staining methodologies) in 1% cholesterol fed rabbits reveal that (18)F-FDG is not always the best tracer. Vascular foam cell content is reflected by (111)In-HIG > (125)I-oxLp(a) > (18)F-FDG > (125)I-LDL (Brammen L, Palumbo B, Lupattelli G et al. Unpublished data). A close correlation to Framingham risk score is for example not helpful, as this score has a low predictive value of only 0.6. The available clinical correlations between (18)F-FDG-uptake and arterial wall characteristics are poor. For

  4. Brain Basics: Know Your Brain

    MedlinePlus

    ... fact sheet is a basic introduction to the human brain. It may help you understand how the healthy ... largest and most highly developed part of the human brain: it consists primarily of the cerebrum ( 2 ) and ...

  5. In vivo non-invasive serial monitoring of FDG-PET progression and regression in a rabbit model of atherosclerosis.

    PubMed

    Worthley, Stephen G; Zhang, Zhuang Y; Machac, Josef; Helft, Gérard; Tang, Cheuk; Liew, Gary Y H; Zaman, Azfar G; Worthley, Matthew I; Fayad, Zahi A; Buchsbaum, Monte S; Fuster, Valentin; Badimon, Juan J

    2009-03-01

    We investigated the ability of fluorodeoxyglucose positron emission tomography (FDG PET) imaging to serially monitor macrophage content in a rabbit model of atherosclerosis. Atherosclerosis was induced in rabbits (n = 8) by a combination of atherogenic diet and balloon denudation of the aorta. At the end of nine months, the rabbits were randomized to a further six months of the same atherogenic diet (progression group) or normal diet (regression group). In vivo uptake of FDG by the thoracic aorta was measured using aortic uptake-to-blood radioactivity ratios at the start and end of the randomized period. A significant increase in FDG uptake of the progression group after continued cholesterol feeding (aortic uptake-to-blood radioactivity: 0.57 +/- 0.02 to 0.68 +/- 0.02, P = 0.001), and a corresponding fall in FDG uptake of the regression group after returning to a normal chow diet (aortic uptake-to-blood radioactivity ratios: 0.67 +/- 0.02 to 0.53 +/- 0.02, P < 0.0001). FDG PET can quantify in vivo macrophage content and serially monitor changes in FDG activity in this rabbit model.

  6. Sclerosing angiomatoid nodular transformation (SANT) of the spleen: a case report with FDG-PET findings and literature review

    PubMed Central

    Imamura, Yumi; Hatta, Kazuha; Seshimo, Akiyoshi; Sawada, Tatsuo; Abe, Koichiro; Sakai, Shuji

    2016-01-01

    We report the 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of sclerosing angiomatoid nodular transformation (SANT) of the spleen. The patient was a 37-year-old woman with a splenic mass incidentally found on abdominal ultrasound. FDG-PET/CT showed weak FDG accumulation (maximum standardized uptake value = 3.65). An unenhanced CT scan showed a low density and well-circumscribed splenic tumor that demonstrated weak enhancement from the arterial to delayed phase. Although hemangioma or hamartoma of the spleen was preoperatively diagnosed, histopathological examination revealed SANT. Therefore, when a splenic tumor with weak contrast medium enhancement and low FDG accumulation is observed, SANT should be considered as a differential diagnosis. Although CT and magnetic resonance imaging features of SANT have been reported, there are few reports on FDG-PET/CT findings. We report the radiological features of SANT, including FDG-PET/CT, and review the literature on SANT. PMID:27570634

  7. Estimate of FDG excretion by means of compartmental analysis and ant colony optimization of nuclear medicine data.

    PubMed

    Garbarino, Sara; Caviglia, Giacomo; Brignone, Massimo; Massollo, Michela; Sambuceti, Gianmario; Piana, Michele

    2013-01-01

    [(18)F]fluoro-2-deoxy-D-glucose (FDG) is one of the most utilized tracers for positron emission tomography (PET) applications in oncology. FDG-PET relies on higher glycolytic activity in tumors compared to normal structures as the basis of image contrast. As a glucose analog, FDG is transported into malignant cells which typically exhibit an increased radioactivity. However, different from glucose, FDG is not reabsorbed by the renal system and is excreted to the bladder. The present paper describes a novel computational method for the quantitative assessment of this excretion process. The method is based on a compartmental analysis of FDG-PET data in which the excretion process is explicitly accounted for by the bladder compartment and on the application of an ant colony optimization (ACO) algorithm for the determination of the tracer coefficients describing the FDG transport effectiveness. The validation of this approach is performed by means of both synthetic data and real measurements acquired by a PET device for small animals (micro-PET). Possible oncological applications of the results are discussed in the final section. PMID:24191175

  8. The role of FDG-PET/CT in the evaluation of residual disease in paediatric non-Hodgkin lymphoma.

    PubMed

    Bhojwani, Deepa; McCarville, Mary B; Choi, John K; Sawyer, Jennifer; Metzger, Monika L; Inaba, Hiroto; Davidoff, Andrew M; Gold, Robert; Shulkin, Barry L; Sandlund, John T

    2015-03-01

    (18) F-labelled-fluorodeoxyglucose positron emission tomography (FDG-PET) findings are challenging to interpret for residual disease versus complete response in paediatric patients with non-Hodgkin lymphoma (NHL). A biopsy is often warranted to confirm the presence or absence of viable tumour if there is clinical or radiographic evidence of residual disease. In this study, we compared conventional imaging and FDG-PET/computerized tomography (CT) findings with biopsy results in 18 children with NHL. Our goal was to provide additional data to establish more reliable criteria for response evaluation. Residual disease was suspected after conventional imaging alone in eight patients, after FDG-PET/CT alone in three and after both modalities in seven patients. Biopsy confirmed the presence of viable tumour in two patients. Two additional patients experienced progressive disease or relapse. The sensitivity and negative predictive value of FDG-PET/CT using the London criteria to indicate residual tumour detectable by biopsy were 100%, but specificity was low (60%), as was the positive predictive value (25%). Thus, in this study, a negative FDG-PET/CT finding was a good indicator of complete remission. However, because false-positive FDG-PET/CT findings are common, biopsy and close monitoring are required for accurate determination of residual disease in individual patients.

  9. Novel synthesis and initial preclinical evaluation of (18)F-[FDG] labeled rhodamine: a potential PET myocardial perfusion imaging agent.

    PubMed

    AlJammaz, Ibrahim; Al-Otaibi, Basim; AlHindas, Hussein; Okarvi, Subhani M

    2015-10-01

    Myocardial perfusion imaging is one of the most commonly performed investigations in nuclear medicine studies. Due to the clinical importance of [(18)F]-fluoro-2-deoxy-D-glucose ([(18)F]-FDG) and its availability in almost every PET center, a new radiofluorinated [(18)F]-FDG-rhodamine conjugate was synthesized using [(18)F]-FDG as a prosthetic group. In a convenient and simple one-step radiosynthesis, [(18)F]-FDG-rhodamine conjugate was prepared in quantitative radiochemical yields, with total synthesis time of nearly 20 min and radiochemical purity of greater than 98%, without the need for HPLC purification, which make these approaches amenable for automation. Biodistribution studies in normal rats at 60 min post-injection demonstrated a high uptake in the heart (>11% ID/g) and favorable pharmacokinetics. Additionally, [(18)F]-FDG-rhodamine showed an extraction value of 27.63%±5.12% in rat hearts. These results demonstrate that [(18)F]-FDG-rhodamine conjugate may be useful as an imaging agent for the positron emission tomography evaluation of myocardial perfusion. PMID:26160144

  10. Hepatocellular adenoma showing high uptake of (18)F-fluorodeoxyglucose (FDG) via an increased expression of glucose transporter 2 (GLUT-2).

    PubMed

    Nakashima, Takaaki; Takayama, Yukihisa; Nishie, Akihiro; Asayama, Yoshiki; Baba, Shingo; Yamashita, Youichi; Shirabe, Ken; Kubo, Yuichiro; Hida, Tomoyuki; Honda, Hiroshi

    2014-01-01

    Hepatocellular adenoma (HCA) is a benign liver neoplasm composed of hepatocytes. We experienced HCA demonstrating a high uptake of (18)F-fluorodeoxyglucose (FDG) on positron emission tomography-computed tomography, mimicking a malignant tumor. The mechanism underlying the uptake of FDG has not been identified. Here, we discuss that an enhancement of glucose metabolism via an increased expression of glucose transporter 2 may have a role in the high uptake of FDG shown by HCAs.

  11. Use of [18F]FDG PET to Monitor The Development of Cardiac Allograft Rejection

    PubMed Central

    Daly, Kevin P.; Dearling, Jason L. J.; Seto, Tatsuichiro; Dunning, Patricia; Fahey, Frederic; Packard, Alan B.; Briscoe, David M.

    2014-01-01

    Background Positron Emission Tomography (PET) has the potential to be a specific, sensitive and quantitative diagnostic test for transplant rejection. To test this hypothesis, we evaluated 18F-labeled fluorodeoxyglucose ([18F]FDG) and 13N-labeled ammonia ([13N]NH3) small animal PET imaging in a well-established murine cardiac rejection model. Methods Heterotopic transplants were performed using minor MHC mismatched B6.C-H2bm12 donor hearts in C57BL/6(H-2b) recipients. C57BL/6 donor hearts into C57BL/6 recipients served as isograft controls. [18F]FDG PET imaging was performed weekly between post-transplant days 7 and 42 and the percent injected dose was computed for each graft. [13N]NH3 imaging was performed to evaluate myocardial perfusion. Results There was a significant increase in [18F]FDG uptake in allografts from day 14 to day 21 (1.6% to 5.2%; P<0.001) and uptake in allografts was significantly increased on post-transplant days 21 (5.2% vs. 0.9%; P=0.005) and 28 (4.8% vs. 0.9%; P=0.006) compared to isograft controls. Furthermore, [18F]FDG uptake correlated with an increase in rejection within allografts between days 14 and 28 post-transplant. Finally, the uptake of [13N]NH3 was significantly lower relative to the native heart in allografts with chronic vasculopathy compared to isograft controls on day 28 (P=0.01). Conclusions PET imaging with [18F]FDG can be used following transplantation to monitor the evolution of rejection. In addition, decreased uptake of [13N]NH3 in rejecting allografts may be reflective of decreased myocardial blood flow. These data suggest that combined [18F]FDG and [13N]NH3 PET imaging could be used as a non-invasive, quantitative technique for serial monitoring of allograft rejection and has potential application in human transplant recipients. PMID:25675207

  12. The Brains Behind the Brain.

    ERIC Educational Resources Information Center

    D'Arcangelo, Marcia

    1998-01-01

    Interviews with five neuroscientists--Martin Diamond, Pat Wolfe, Robert Sylwester, Geoffrey Caine, and Eric Jensen--disclose brain-research findings of practical interest to educators. Topics include brain physiology, environmental enrichment, memorization, windows of learning opportunity, brain learning capacity, attention span, student interest,…

  13. APOE-by-sex interactions on brain structure and metabolism in healthy elderly controls

    PubMed Central

    de Leon, Mony J; Alcolea, Daniel; Pegueroles, Jordi; Montal, Victor; Carmona-Iragui, María; Sala, Isabel; Sánchez-Saudinos, María-Belén; Antón-Aguirre, Sofía; Morenas-Rodríguez, Estrella; Camacho, Valle; Falcón, Carles; Pavía, Javier; Ros, Domènec; Clarimón, Jordi; Blesa, Rafael; Lleó, Alberto; Fortea, Juan

    2015-01-01

    Background The APOE effect on Alzheimer Disease (AD) risk is stronger in women than in men but its mechanisms have not been established. We assessed the APOE-by-sex interaction on core CSF biomarkers, brain metabolism and structure in healthy elderly control individuals (HC). Methods Cross-sectional study. HC from the Alzheimer’s Disease Neuroimaging Initiative with available CSF (n = 274) and/or 3T-MRI (n = 168) and/or a FDG-PET analyses (n = 328) were selected. CSF amyloid-β1–42 (Aβ1–42), total-tau (t-tau) and phospho-tau (p-tau181p) levels were measured by Luminex assays. We analyzed the APOE-by-sex interaction on the CSF biomarkers in an analysis of covariance (ANCOVA). FDG uptake was analyzed by SPM8 and cortical thickness (CTh) was measured by FreeSurfer. FDG and CTh difference maps were derived from interaction and group analyses. Results APOE4 carriers had lower CSF Aβ1–42 and higher CSF p-tau181p values than non-carriers, but there was no APOE-by-sex interaction on CSF biomarkers. The APOE-by-sex interaction on brain metabolism and brain structure was significant. Sex stratification showed that female APOE4 carriers presented widespread brain hypometabolism and cortical thinning compared to female non-carriers whereas male APOE4 carriers showed only a small cluster of hypometabolism and regions of cortical thickening compared to male non-carriers. Conclusions The impact of APOE4 on brain metabolism and structure is modified by sex. Female APOE4 carriers show greater hypometabolism and atrophy than male carriers. This APOE-by-sex interaction should be considered in clinical trials in preclinical AD where APOE4 status is a selection criterion. PMID:26397226

  14. Incidental detection of increased (18)F-FDG uptake and its follow-up in patients with granulomatous prostatitis after BCG treatment for urinary bladder cancer.

    PubMed

    Kim, Choon-Young; Lee, Sang-Woo; Yoon, Ghilsuk; Jeong, Shin Young; Ahn, Byeong-Cheol; Lee, Jaetae

    2014-01-01

    Incidental prostate uptake of fluorine-18-fluorodeoxyglucose in positron emission tomography/computed tomography ((18)F-FDG PET/CT) may represent malignancies like prostate malignancy, inflammation or benign prostatic lesions. We report two cases of bacillus Calmette-Guérin (BCG)-induced granulomatous prostatitis that showed (18)F-FDG uptake of the prostate gland on (18)F-FDG PET/CT in patients who had previously received intravesical BCG treatment for bladder cancer. The degree of (18)F-FDG uptake was decreased on the follow-up PET/CT scan after one year, without any specific treatment.

  15. Progressing Sclerosing Mesenteritis (Mesenteric Panniculitis) Mimics Progression of Malignancy After Neoadjuvant Chemotherapy for Gastric Adenocarcinoma on Serial 18F-FDG PET/CT.

    PubMed

    Makis, William

    2016-04-01

    A 62-year-old man was diagnosed with a moderately differentiated gastric adenocarcinoma in the proximal stomach. A staging 18F-FDG PET/CT showed an intensely FDG-avid gastric mass, as well as a mildly FDG-avid misty nodular mesentery. After 3 cycles of neoadjuvant chemotherapy, a follow-up PET/CT showed partial response of the gastric primary, with increase in the size of nodules in the mesentery and increased FDG uptake, raising concern of secondary malignancy. Biopsy of the mesentery revealed xanthogranulomatous inflammation, consistent with sclerosing mesenteritis. PMID:26359565

  16. IgG4-Related Kidney Disease in a Patient With History of Breast Cancer: Findings on 18F-FDG PET/CT.

    PubMed

    Krebs, Simone; Monti, Serena; Seshan, Surya; Fox, Josef; Mannelli, Lorenzo

    2016-08-01

    A 64-year-old African American woman with history of stage III breast carcinoma, 3 years after complete response to therapy, presents with progressive fatigue, increasing arthralgia, and unintentional weight loss of 15 lb in 3 months. An F-FDG PET demonstrated new diffuse FDG avidity of the renal parenchyma, new FDG-avid foci in pancreas and lungs, and new FDG-avid lymph nodes above and below the diaphragm. While a retroperitoneal lymph node biopsy was inconclusive, a kidney biopsy resulted in diagnosis of diffuse, severe, IgG4-related tubulointerstitial nephritis. Treatment with corticosteroid led to complete resolution of the symptoms and PET findings.

  17. A rare case of primary pulmonary synovial sarcoma in a pediatric patient evaluated by (18)F-FDG PET/CT.

    PubMed

    Treglia, Giorgio; Caldarella, Carmelo; Taralli, Silvia

    2014-02-01

    We describe a rare case of primary pulmonary synovial sarcoma (PPSS) that occurred in a pediatric patient and evaluated by 18F-FDG PET/CT. A 14-year-old male patient underwent 18F-FDG PET/CT for metabolic characterization of a left pulmonary mass which showed increased 18F-FDG uptake (SUVmax = 4.5). Based on this PET/CT finding, the patient underwent a CTguided biopsy which demonstrated the presence of a PPSS. Other sites of disease were excluded. 18F-FDG PET/CT may be useful for staging pediatric patients with PPSS. PMID:24536091

  18. IgG4-Related Kidney Disease in a Patient With History of Breast Cancer: Findings on 18F-FDG PET/CT.

    PubMed

    Krebs, Simone; Monti, Serena; Seshan, Surya; Fox, Josef; Mannelli, Lorenzo

    2016-08-01

    A 64-year-old African American woman with history of stage III breast carcinoma, 3 years after complete response to therapy, presents with progressive fatigue, increasing arthralgia, and unintentional weight loss of 15 lb in 3 months. An F-FDG PET demonstrated new diffuse FDG avidity of the renal parenchyma, new FDG-avid foci in pancreas and lungs, and new FDG-avid lymph nodes above and below the diaphragm. While a retroperitoneal lymph node biopsy was inconclusive, a kidney biopsy resulted in diagnosis of diffuse, severe, IgG4-related tubulointerstitial nephritis. Treatment with corticosteroid led to complete resolution of the symptoms and PET findings. PMID:27187735

  19. Evaluation of high-risk melanoma: comparison of [18F]FDG PET and high-dose 67Ga SPET.

    PubMed

    Kalff, Victor; Hicks, Rodney J; Ware, Robert E; Greer, Brett; Binns, David S; Hogg, Annette

    2002-04-01

    Recently the potential of whole-body positron emission tomography scanning using 18F-fluorodeoxyglucose (FDG PET) has led to renewed interest in the use of functional imaging for the detection of occult metastatic melanoma. This study compared dedicated FDG PET with high-dose gallium-67 imaging incorporating whole-body scanning and comprehensive single-photon emission tomography (SPET) in 122 cases (121 patients) in which the two scans were performed <6 weeks apart. All patients were at high clinical risk of occult metastatic disease and 49 (40%) had abnormality suggestive of metastatic disease by at least one functional imaging technique. Discrepant scan findings were followed up to determine which technique more accurately reflected disease status. There were 23/122 (19%; 95% CI: 12%-26%) cases with discordant scan results in respect of either the presence of melanoma (11 cases) or the extent of disease (12 cases). PET correctly identified more disease than 67Ga SPET in 14 cases (including three incidental primary tumours) and was true negative in three further patients with abnormal 67Ga SPET. There were six patients with true positive 67Ga SPET in whom FDG PET was false negative (one small cutaneous deposit, one residual axillary node rated equivocal on FDG PET due to postoperative changes, one adrenal metastasis inseparable from renal activity on FDG PET and three cases in which sites missed on FDG PET were seen on 67Ga SPET. Thus, FDG PET provided incremental diagnostic information compared with 67Ga SPET in 17/23 patients, while 67Ga SPET provided incremental information compared with PET in 6/23 cases ( P=0.035). Based on Australian Medicare reimbursement levels, the net cost per patient with clinical management benefit of replacing 67Ga SPET with FDG PET was estimated to be less than EUR 1,750. These results suggest that FDG PET provides incremental and clinically important information in around 10% of patients at a low incremental cost which, combined

  20. Primary pulmonary solitary fibrous tumour with brain metastases.

    PubMed

    Ozeki, Naoki; Kawaguchi, Koji; Taniguchi, Tetsuo; Yokoi, Kohei

    2014-02-01

    Solitary fibrous tumour (SFT) is a mesenchymal neoplasm of subendothelial origin that can be found in all anatomical locations, but rarely in the lungs. A 71-year old female was referred to our hospital because of the increase in size of a solitary pulmonary mass. Chest contrast-enhanced dynamic computed tomography showed a well-circumscribed lobulated mass measuring 3.1×1.6 cm in the posterior segment of the right upper lobe of the lung. Positron emission tomography with 18F-fluorodeoxyglucose (FDG) demonstrated that the mass had high FDG uptake. A right upper lobectomy of the lung and mediastinal lymphadenectomy were performed. The tumour was pathologically diagnosed as an SFT. Seven months later, the patient was found to have brain metastases of the tumour, which led to dizziness. A craniotomy and successive radiosurgery with a gamma knife were performed for the metastatic tumours. She is still alive without evidence of disease 12 months after the treatment of the metastases. Pulmonary SFT seldom behaves aggressively, and only two previous cases of primary pulmonary SFT with brain metastases have been reported. Local therapy including surgery and radiotherapy against metastases from SFT could help improve the survival of such patients.

  1. The Functional Networks of Prepulse Inhibition: Neuronal Connectivity Analysis Based on FDG-PET in Awake and Unrestrained Rats.

    PubMed

    Rohleder, Cathrin; Wiedermann, Dirk; Neumaier, Bernd; Drzezga, Alexander; Timmermann, Lars; Graf, Rudolf; Leweke, F Markus; Endepols, Heike

    2016-01-01

    Prepulse inhibition (PPI) is a neuropsychological process during which a weak sensory stimulus ("prepulse") attenuates the motor response ("startle reaction") to a subsequent strong startling stimulus. It is measured as a surrogate marker of sensorimotor gating in patients suffering from neuropsychological diseases such as schizophrenia, as well as in corresponding animal models. A variety of studies has shown that PPI of the acoustical startle reaction comprises three brain circuitries for: (i) startle mediation, (ii) PPI mediation, and (iii) modulation of PPI mediation. While anatomical connections and information flow in the startle and PPI mediation pathways are well known, spatial and temporal interactions of the numerous regions involved in PPI modulation are incompletely understood. We therefore combined [(18)F]fluoro-2-deoxyglucose positron-emission-tomography (FDG-PET) with PPI and resting state control paradigms in awake rats. A battery of subtractive, correlative as well as seed-based functional connectivity analyses revealed a default mode-like network (DMN) active during resting state only. Furthermore, two functional networks were observed during PPI: Metabolic activity in the lateral circuitry was positively correlated with PPI effectiveness and involved the auditory system and emotional regions. The medial network was negatively correlated with PPI effectiveness, i.e., associated with startle, and recruited a spatial/cognitive network. Our study provides evidence for two distinct neuronal networks, whose continuous interplay determines PPI effectiveness in rats, probably by either protecting the prepulse or facilitating startle processing. Discovering similar networks affected in neuropsychological disorders may help to better understand mechanisms of sensorimotor gating deficits and provide new perspectives for therapeutic strategies. PMID:27493627

  2. The Functional Networks of Prepulse Inhibition: Neuronal Connectivity Analysis Based on FDG-PET in Awake and Unrestrained Rats

    PubMed Central

    Rohleder, Cathrin; Wiedermann, Dirk; Neumaier, Bernd; Drzezga, Alexander; Timmermann, Lars; Graf, Rudolf; Leweke, F. Markus; Endepols, Heike

    2016-01-01

    Prepulse inhibition (PPI) is a neuropsychological process during which a weak sensory stimulus (“prepulse”) attenuates the motor response (“startle reaction”) to a subsequent strong startling stimulus. It is measured as a surrogate marker of sensorimotor gating in patients suffering from neuropsychological diseases such as schizophrenia, as well as in corresponding animal models. A variety of studies has shown that PPI of the acoustical startle reaction comprises three brain circuitries for: (i) startle mediation, (ii) PPI mediation, and (iii) modulation of PPI mediation. While anatomical connections and information flow in the startle and PPI mediation pathways are well known, spatial and temporal interactions of the numerous regions involved in PPI modulation are incompletely understood. We therefore combined [18F]fluoro-2-deoxyglucose positron-emission-tomography (FDG-PET) with PPI and resting state control paradigms in awake rats. A battery of subtractive, correlative as well as seed-based functional connectivity analyses revealed a default mode-like network (DMN) active during resting state only. Furthermore, two functional networks were observed during PPI: Metabolic activity in the lateral circuitry was positively correlated with PPI effectiveness and involved the auditory system and emotional regions. The medial network was negatively correlated with PPI effectiveness, i.e., associated with startle, and recruited a spatial/cognitive network. Our study provides evidence for two distinct neuronal networks, whose continuous interplay determines PPI effectiveness in rats, probably by either protecting the prepulse or facilitating startle processing. Discovering similar networks affected in neuropsychological disorders may help to better understand mechanisms of sensorimotor gating deficits and provide new perspectives for therapeutic strategies. PMID:27493627

  3. In Vivo ¹⁸F-FDG-PET Imaging in Mouse Atherosclerosis.

    PubMed

    Mateo, Jesús; Bilbao, Izaskun; Vaquero, Juan José; Ruiz-Cabello, Jesús; España, Samuel

    2015-01-01

    Positron emission tomography (PET) is an important technique in cardiovascular research. Vascular inflammation detected by fluorodeoxyglucose (FDG)-PET has been shown to predict cardiovascular (CV) events independent of traditional risk factors and is also highly associated with overall burden of atherosclerosis. The use of PET imaging in mouse models of atherosclerosis is challenged by the reduced size of the scanned organs. However, the last generation of dedicated PET scanners has an improved spatial resolution (<1 mm) and increased sensitivity allowing those studies to be performed. Here, we describe a procedure to perform FDG-PET experiments in atherosclerosis mouse models, the required equipment for animal handling and imaging, and the tools and procedures for image analysis and validation of the results.

  4. Increased 18F-FDG Uptake in the Spleen and Multiple Lymph Nodes in Dengue Fever.

    PubMed

    Jinguji, Megumi; Kajiya, Yoriko; Nakajo, Masatoyo; Nakajo, Masayuki; Yoshiura, Takashi

    2016-05-01

    A 62-year-old man underwent a whole-body FDG PET/CT for annual cancer screening. By an interview, he had an epigastric pain, and his body temperature was 37.0°C on the day. He just came back home from a travel to Southeast Asia 1 week ago and had presented with chill, high fever (temperature, 39.6°C), arthralgia, myalgia, and skin rash a few days before. Dengue fever was diagnosed by detecting dengue virus type 1 genome and antibody to the virus accompanied by thrombocytopenia and leukopenia. PET/CT examination revealed increased FDG uptake in the spleen and multiple lymph nodes. PMID:26825211

  5. Design Features Of Microfluidic Reactor For [18F]FDG Radiopharmaceutical Synthesis

    NASA Astrophysics Data System (ADS)

    Oh, J. H.; Lee, B. N.; Nam, K. R.; Attla, G. A.; Lee, K. C.; Cjai, J. S.

    2011-06-01

    Microfluidic reactor exhibits advantages for radiopharmaceutical synthesis. Microfluidic chips can reduce the time for radiosynthesis using tiny quantities of chemical compounds. It also has a good heat transfer, performance and provides an integrated system including synthesis, separation, and purification. These advantages make FDG production. So we have designed a microreactor chip which included the whole chemical processing; water evaporation, solvent exchange, radiofluorination and so on. It was designed by using a commercial 3D CAD modeling program CATIA V5, heat transfer performance was analyzed by ANSYS, and CFX was used for analyzing fluid performance. This paper described the design of FDG synthesis system on a microchip, the relevant locations of its parts, both heat and fluid performance efficiency analysis.

  6. Cholecystokinin-Assisted Hydrodissection of the Gallbladder Fossa during FDG PET/CT-guided Liver Ablation

    SciTech Connect

    Tewari, Sanjit O.; Petre, Elena N.; Osborne, Joseph; Sofocleous, Constantinos T.

    2013-12-15

    A 68-year-old female with colorectal cancer developed a metachronous isolated fluorodeoxyglucose-avid (FDG-avid) segment 5/6 gallbladder fossa hepatic lesion and was referred for percutaneous ablation. Pre-procedure computed tomography (CT) images demonstrated a distended gallbladder abutting the segment 5/6 hepatic metastasis. In order to perform ablation with clear margins and avoid direct puncture and aspiration of the gallbladder, cholecystokinin was administered intravenously to stimulate gallbladder contraction before hydrodissection. Subsequently, the lesion was ablated successfully with sufficient margins, of greater than 1.0 cm, using microwave with ultrasound and FDG PET/CT guidance. The patient tolerated the procedure very well and was discharged home the next day.

  7. Long-term quality assurance of [18F]-fluorodeoxyglucose (FDG) manufacturing

    PubMed Central

    Gaspar, Ludovit; Reich, Michal; Kassai, Zoltan; Macasek, Fedor; Rodrigo, Luis; Kruzliak, Peter; Kovac, Peter

    2016-01-01

    Nine years of experience with 2286 commercial synthesis allowed us to deliver comprehensive information on the quality of 18F-FDG production. Semi-automated FDG production line using Cyclone 18/9 machine (IBA Belgium), TRACERLab MXFDG synthesiser (GE Health, USA) using alkalic hydrolysis, grade “A” isolator with dispensing robotic unit (Tema Sinergie, Italy), and automatic control system under GAMP5 (minus2, Slovakia) was assessed by TQM tools as highly reliable aseptic production line, fully compliant with Good Manufacturing Practice and just-in-time delivery of FDG radiopharmaceutical. Fluoride-18 is received in steady yield and of very high radioactive purity. Synthesis yields exhibited high variance connected probably with quality of disposable cassettes and chemicals sets. Most performance non-conformities within the manufacturing cycle occur at mechanical nodes of dispensing unit. The long-term monitoring of 2286 commercial synthesis indicated high reliability of automatic synthesizers. Shewhart chart and ANOVA analysis showed that minor non-compliances occurred were mostly caused by the declinations of less experienced staff from standard operation procedures, and also by quality of automatic cassettes. Only 15 syntheses were found unfinished and in 4 cases the product was out-of-specification of European Pharmacopoeia. Most vulnerable step of manufacturing was dispensing and filling in grade “A” isolator. Its cleanliness and sterility was fully controlled under the investigated period by applying hydrogen peroxide vapours (VHP). Our experience with quality assurance in the production of [18F]-fluorodeoxyglucose (FDG) at production facility of BIONT based on TRACERlab MXFDG production module can be used for bench-marking of the emerging manufacturing and automated manufacturing systems. PMID:27508102

  8. Long-term quality assurance of [(18)F]-fluorodeoxyglucose (FDG) manufacturing.

    PubMed

    Gaspar, Ludovit; Reich, Michal; Kassai, Zoltan; Macasek, Fedor; Rodrigo, Luis; Kruzliak, Peter; Kovac, Peter

    2016-01-01

    Nine years of experience with 2286 commercial synthesis allowed us to deliver comprehensive information on the quality of (18)F-FDG production. Semi-automated FDG production line using Cyclone 18/9 machine (IBA Belgium), TRACERLab MXFDG synthesiser (GE Health, USA) using alkalic hydrolysis, grade "A" isolator with dispensing robotic unit (Tema Sinergie, Italy), and automatic control system under GAMP5 (minus2, Slovakia) was assessed by TQM tools as highly reliable aseptic production line, fully compliant with Good Manufacturing Practice and just-in-time delivery of FDG radiopharmaceutical. Fluoride-18 is received in steady yield and of very high radioactive purity. Synthesis yields exhibited high variance connected probably with quality of disposable cassettes and chemicals sets. Most performance non-conformities within the manufacturing cycle occur at mechanical nodes of dispensing unit. The long-term monitoring of 2286 commercial synthesis indicated high reliability of automatic synthesizers. Shewhart chart and ANOVA analysis showed that minor non-compliances occurred were mostly caused by the declinations of less experienced staff from standard operation procedures, and also by quality of automatic cassettes. Only 15 syntheses were found unfinished and in 4 cases the product was out-of-specification of European Pharmacopoeia. Most vulnerable step of manufacturing was dispensing and filling in grade "A" isolator. Its cleanliness and sterility was fully controlled under the investigated period by applying hydrogen peroxide vapours (VHP). Our experience with quality assurance in the production of [(18)F]-fluorodeoxyglucose (FDG) at production facility of BIONT based on TRACERlab MXFDG production module can be used for bench-marking of the emerging manufacturing and automated manufacturing systems.

  9. Long-term quality assurance of [(18)F]-fluorodeoxyglucose (FDG) manufacturing.

    PubMed

    Gaspar, Ludovit; Reich, Michal; Kassai, Zoltan; Macasek, Fedor; Rodrigo, Luis; Kruzliak, Peter; Kovac, Peter

    2016-01-01

    Nine years of experience with 2286 commercial synthesis allowed us to deliver comprehensive information on the quality of (18)F-FDG production. Semi-automated FDG production line using Cyclone 18/9 machine (IBA Belgium), TRACERLab MXFDG synthesiser (GE Health, USA) using alkalic hydrolysis, grade "A" isolator with dispensing robotic unit (Tema Sinergie, Italy), and automatic control system under GAMP5 (minus2, Slovakia) was assessed by TQM tools as highly reliable aseptic production line, fully compliant with Good Manufacturing Practice and just-in-time delivery of FDG radiopharmaceutical. Fluoride-18 is received in steady yield and of very high radioactive purity. Synthesis yields exhibited high variance connected probably with quality of disposable cassettes and chemicals sets. Most performance non-conformities within the manufacturing cycle occur at mechanical nodes of dispensing unit. The long-term monitoring of 2286 commercial synthesis indicated high reliability of automatic synthesizers. Shewhart chart and ANOVA analysis showed that minor non-compliances occurred were mostly caused by the declinations of less experienced staff from standard operation procedures, and also by quality of automatic cassettes. Only 15 syntheses were found unfinished and in 4 cases the product was out-of-specification of European Pharmacopoeia. Most vulnerable step of manufacturing was dispensing and filling in grade "A" isolator. Its cleanliness and sterility was fully controlled under the investigated period by applying hydrogen peroxide vapours (VHP). Our experience with quality assurance in the production of [(18)F]-fluorodeoxyglucose (FDG) at production facility of BIONT based on TRACERlab MXFDG production module can be used for bench-marking of the emerging manufacturing and automated manufacturing systems. PMID:27508102

  10. Preoperative Evaluation of Renal Cell Carcinoma by Using 18F-FDG PET/CT

    PubMed Central

    Takahashi, Miwako; Kume, Haruki; Koyama, Keitaro; Nakagawa, Tohru; Fujimura, Tetsuya; Morikawa, Teppei; Fukayama, Masashi; Homma, Yukio; Ohtomo, Kuni; Momose, Toshimitsu

    2015-01-01

    Purpose This study aimed to characterize the FDG uptake of renal cell carcinoma (RCC) by the pathological subtype and nuclear grade. Patients and Methods We retrospectively identified patients who underwent 18F-FDG PET and subsequent partial or radical nephrectomy for renal tumors. The relationships of the SUV of renal tumor with subtypes, nuclear grade, and clinicopathological variables were investigated. Results Ninety-two tumors were analyzed, including 52 low-grade (G1 and G2) and 18 high-grade (G3 and G4) clear cell RCC; 7 chromophobe, 5 papillary, and 1 unclassified RCC; and 9 benign tumors (7 angiomyolipoma and 2 oncocytoma). The SUVs of high-grade clear cell RCC (mean ± SD, 6.8 ± 5.1) and papillary RCC (6.6 ± 3.7) were significantly higher than that of the controls (2.2 ± 0.3). The SUV of high-grade clear cell RCC was higher than that of low-grade tumors (median, 4.0 vs. 2.2; P < 0.001). The optimal SUV cutoff value of 3.0 helped to differentiate high-grade from low-grade clear cell RCC, with 89% sensitivity and 87% specificity. On multiple regression analysis, a high grade was the most significant predictor of SUV for clear cell RCC. Conclusions FDG uptake higher than that observed in normal kidney tissues suggests a high-grade clear cell RCC or papillary RCC subtype. FDG-PET using SUV may have a role in prediction of pathological grade of renal tumor. PMID:26164183

  11. (18)F-FDG PET/CT findings in a case with HIV (-) Kaposi sarcoma.

    PubMed

    Ozdemir, E; Poyraz, N Y; Keskin, M; Kandemir, Z; Turkolmez, S

    2014-01-01

    Although mucocutaneous sites are the most frequently encountered sites of involvement, Kaposi Sarcoma (KS) may also occasionally involve the breast and the skeletal, endocrine, urinary and nervous systems.. Various imaging modalities may be used to delineate the extent of the disease by detecting unexpected sites of involvement. Herein, we report a case of classical type KS, in whom staging with (18)F-FDG PET/CT imaging disclosed widespread disease and unexpected findings of bone and salivary gland involvement.

  12. Stage-dependent agreement between cerebrospinal fluid proteins and FDG-PET findings in Alzheimer's disease.

    PubMed

    Yakushev, Igor; Muller, Matthias J; Buchholz, Hans-Georg; Lang, Ulrike; Rossmann, Heidi; Hampel, Harald; Schreckenberger, Mathias; Fellgiebel, Andreas

    2012-02-01

    Cerebral hypometabolism and abnormal levels of amyloid beta (Aβ), total (t-tau) and phosphorylated tau (ptau) proteins in cerebrospinal fluid (CSF) are established biomarkers of Alzheimer's disease (AD). We examined the agreement between these biomarkers in a single center study of patients with AD of severity extending over a wide range. Forty seven patients (MMSE 21.4 ± 3.6, range 13-28 points) with incipient and probable AD underwent positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) and lumbar puncture for CSF assays of Aβ1-42, p-tau181, and t-tau. All findings were classified as either positive or negative for AD. Statistical analyses were performed for the whole sample (n=47) and for the subgroups stratified as mild (MMSE > 20 points, n=30) and moderate (MMSE < 21 points, n=17) AD. In the whole patient sample, the agreement with the FDG-PET finding was 77% (chance-corrected kappa [κ]=0.34, p=0.016) for t-tau, 68% (κ=0.10, n.s.) for p-tau181, and 68% (κ=0.04, n.s.) for Aβ1-42. No significant agreement was found in the mild AD subgroup, while there was a strong agreement for t-tau (94%, κ=0.77, p=0.001) and p-tau181 (88%, κ=0.60, p=0.014) in the moderate AD group. A significant agreement between the FDG-PET and CSF tau findings in patients with AD supports the view that both are markers of neurodegeneration. CSF tau proteins and FDG-PET might substitute each other as supportive diagnostic tools in patients with suspected moderate-to-severe Alzheimer's dementia, while this is not the case in subjects at an earlier disease stage. PMID:22044023

  13. Reference Cluster Normalization Improves Detection of Frontotemporal Lobar Degeneration by Means of FDG-PET

    PubMed Central

    Dukart, Juergen; Perneczky, Robert; Förster, Stefan; Barthel, Henryk; Diehl-Schmid, Janine; Draganski, Bogdan; Obrig, Hellmuth; Santarnecchi, Emiliano; Drzezga, Alexander; Fellgiebel, Andreas; Frackowiak, Richard; Kurz, Alexander; Müller, Karsten; Sabri, Osama; Schroeter, Matthias L.; Yakushev, Igor

    2013-01-01

    Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly subjects. FDG-PET was conducted at two centers using different acquisition protocols: 41 FTLD patients and 42 controls were studied at center 1, 11 FTLD patients and 13 controls were studied at center 2. All PET images were intensity normalized to the cerebellum, primary sensorimotor cortex (SMC), cerebral global mean (CGM), and a reference cluster with most preserved FDG uptake in the aforementioned patients group of center 1. Metabolic deficits in the patient group at center 1 appeared 1.5, 3.6, and 4.6 times greater in spatial extent, when tracer uptake was normalized to the reference cluster rather than to the cerebellum, SMC, and CGM, respectively. Logistic regression analyses based on normalized values from FTLD-typical regions showed that at center 1, cerebellar, SMC, CGM, and cluster normalizations differentiated patients from controls with accuracies of 86%, 76%, 75% and 90%, respectively. A similar order of effects was found at center 2. Cluster normalization leads to a significant increase of statistical power in detecting early FTLD-associated metabolic deficits. The established FTLD-specific cluster can be used to improve detection of FTLD on a single case basis at independent centers – a decisive step towards early diagnosis and prediction of FTLD syndromes enabling specific therapies in the future. PMID:23451025

  14. Reference cluster normalization improves detection of frontotemporal lobar degeneration by means of FDG-PET.

    PubMed

    Dukart, Juergen; Perneczky, Robert; Förster, Stefan; Barthel, Henryk; Diehl-Schmid, Janine; Draganski, Bogdan; Obrig, Hellmuth; Santarnecchi, Emiliano; Drzezga, Alexander; Fellgiebel, Andreas; Frackowiak, Richard; Kurz, Alexander; Müller, Karsten; Sabri, Osama; Schroeter, Matthias L; Yakushev, Igor

    2013-01-01

    Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly subjects. FDG-PET was conducted at two centers using different acquisition protocols: 41 FTLD patients and 42 controls were studied at center 1, 11 FTLD patients and 13 controls were studied at center 2. All PET images were intensity normalized to the cerebellum, primary sensorimotor cortex (SMC), cerebral global mean (CGM), and a reference cluster with most preserved FDG uptake in the aforementioned patients group of center 1. Metabolic deficits in the patient group at center 1 appeared 1.5, 3.6, and 4.6 times greater in spatial extent, when tracer uptake was normalized to the reference cluster rather than to the cerebellum, SMC, and CGM, respectively. Logistic regression analyses based on normalized values from FTLD-typical regions showed that at center 1, cerebellar, SMC, CGM, and cluster normalizations differentiated patients from controls with accuracies of 86%, 76%, 75% and 90%, respectively. A similar order of effects was found at center 2. Cluster normalization leads to a significant increase of statistical power in detecting early FTLD-associated metabolic deficits. The established FTLD-specific cluster can be used to improve detection of FTLD on a single case basis at independent centers - a decisive step towards early diagnosis and prediction of FTLD syndromes enabling specific therapies in the future. PMID:23451025

  15. Brain tumors.

    PubMed Central

    Black, K. L.; Mazziotta, J. C.; Becker, D. P.

    1991-01-01

    Recent advances in experimental tumor biology are being applied to critical clinical problems of primary brain tumors. The expression of peripheral benzodiazepine receptors, which are sparse in normal brain, is increased as much as 20-fold in brain tumors. Experimental studies show promise in using labeled ligands to these receptors to identify the outer margins of malignant brain tumors. Whereas positron emission tomography has improved the dynamic understanding of tumors, the labeled selective tumor receptors with positron emitters will enhance the ability to specifically diagnose and greatly aid in the pretreatment planning for tumors. Modulation of these receptors will also affect tumor growth and metabolism. Novel methods to deliver antitumor agents to the brain and new approaches using biologic response modifiers also hold promise to further improve the management of brain tumors. Images PMID:1848735

  16. Insights into Intrinsic Brain Networks based on Graph Theory and PET in right- compared to left-sided Temporal Lobe Epilepsy

    PubMed Central

    Vanicek, Thomas; Hahn, Andreas; Traub-Weidinger, Tatjana; Hilger, Eva; Spies, Marie; Wadsak, Wolfgang; Lanzenberger, Rupert; Pataraia, Ekaterina; Asenbaum-Nan, Susanne

    2016-01-01

    The human brain exhibits marked hemispheric differences, though it is not fully understood to what extent lateralization of the epileptic focus is relevant. Preoperative [18F]FDG-PET depicts lateralization of seizure focus in patients with temporal lobe epilepsy and reveals dysfunctional metabolic brain connectivity. The aim of the present study was to compare metabolic connectivity, inferred from inter-regional [18F]FDG PET uptake correlations, in right-sided (RTLE; n = 30) and left-sided TLE (LTLE; n = 32) with healthy controls (HC; n = 31) using graph theory based network analysis. Comparing LTLE and RTLE and patient groups separately to HC, we observed higher lobar connectivity weights in RTLE compared to LTLE for connections of the temporal and the parietal lobe of the contralateral hemisphere (CH). Moreover, especially in RTLE compared to LTLE higher local efficiency were found in the temporal cortices and other brain regions of the CH. The results of this investigation implicate altered metabolic networks in patients with TLE specific to the lateralization of seizure focus, and describe compensatory mechanisms especially in the CH of patients with RTLE. We propose that graph theoretical analysis of metabolic connectivity using [18F]FDG-PET offers an important additional modality to explore brain networks. PMID:27349503

  17. Retroperitoneal Bronchogenic Cyst Presenting Paraadrenal Tumor Incidentally Detected by (18)F-FDG PET/CT.

    PubMed

    Yoon, Ye Ri; Choi, Jiyoun; Lee, Sang Mi; Kim, Yeo Joo; Cho, Hyun Deuk; Lee, Jeong Won; Jeon, Youn Soo

    2015-03-01

    A follow-up (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT scan of a 57-year-old asymptomatic male who had undergone total thyroidectomy for thyroid cancer revealed a 5.0 × 4.0-cm, well-defined, ovoid-shaped mass around the left adrenal gland without definite FDG uptake. On the adrenal CT scan, the left paraadrenal tumor showed high attenuation on the precontrast scan without enhancement. The average Hounsfield unit (HU) was 58.1 on the precontrast scan and 58.4 on the postcontrast scan. The patient underwent laparoscopic adrenalectomy for resection of the left paraadrenal tumor. The final histopathologic examination revealed a bronchogenic cyst. Although retroperitoneal bronchogenic cysts are rare, they should be considered in the differential diagnosis of retroperitoneal cystic tumors. The preoperative diagnosis is difficult, but a contrast-enhanced CT scan or (18)F-FDG PET/CT scan may be useful for differentiating hyperattenuated cysts from other soft tissue masses.

  18. FDG PET and tumour markers in the diagnosis of recurrent and metastatic breast cancer.

    PubMed

    Siggelkow, Wulf; Rath, Werner; Buell, Udalrich; Zimny, Michael

    2004-06-01

    Breast cancer continues to be one of the most common cancers in North America and Western Europe. Positron emission tomography with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG PET) represents a non-invasive functional imaging modality that is based on metabolic characteristics of malignant tumours. In breast cancer, FDG PET is more accurate than conventional methods for staging of distant metastases or local recurrences and enables early assessment of treatment response in patients undergoing primary chemotherapy. Recent data indicate a rationale for the use of FDG PET in cases of asymptomatically elevated tumour marker levels in the presence of uncertain results of conventional imaging. Despite the fact that PET cannot rule out microscopic disease, it does have particular value in providing, in a single examination, a reliable assessment of the true extent of the disease. This technique is complementary to morphological imaging for primary diagnosis, staging and re-staging. It may become the method of choice for the assessment of asymptomatic patients with elevated tumour marker levels. This method, however, cannot replace invasive procedures if microscopic disease is of clinical relevance. PMID:15146295

  19. Static and dynamic (18) FDG-PET in normal hispaniolan Amazon parrots (Amazona ventralis).

    PubMed

    Souza, Marcy J; Wall, Jonathan S; Stuckey, Alan; Daniel, Gregory B

    2011-01-01

    Positron emission tomography (PET) is often used to stage and monitor human cancer and has recently been used in a similar fashion in veterinary medicine. The most commonly used radiopharmaceutical is 2-Deoxy-2-[(18) F]-Fluoro-d-glucose ((18) F-FDG), which is concentrated and trapped within cells that use glucose as their energy substrate. We characterized the normal distribution of (18) F-FDG in 10 healthy Hispaniolan Amazon parrots (Amazona ventralis) by performing whole body PET scans at steady state, 60min after injection. Significant variability was found in the intestinal activity. Avian species are known to reflux fluid and electrolytes from their cloaca into their colon. To evaluate reflux as the cause of variability in intestinal distribution of (18) F-FDG, dynamic PET scans were performed on the coelomic cavity of six Hispaniolan Amazon parrots from time 0 to 60min postinjection of radiotracer. Reflux of radioactive material from the cloaca into the colon occurred in all birds to varying degrees and occurred before 60min. To evaluate the intestinal tract of clinical avian patients, dynamic scans must be performed starting immediately after injection so that increased radioactivity due to metabolism or hypermetabolic lesions such as cancer can be differentiated from increased radioactivity due to reflux of fluid from the cloaca.

  20. 18F-FDG microPET imaging differentiates between septic and aseptic wound healing after orthopedic implant placement

    PubMed Central

    Odekerken, Jim C E; Brans, Boudewijn T; Welting, Tim J M; Walenkamp, Geert H I M

    2014-01-01

    Background and purpose 18F-FDG PET is a widely used tool for molecular imaging of oncological, cardiovascular, and neurological disorders. We evaluated 18F-FDG microPET as an implant osteomyelitis imaging tool using a Staphylococcus aureus-induced peroperative implant infection in rabbits. Methods Intramedullary titanium nails were implanted in contaminated and uncontaminated (control) proximal right tibiae of rabbits. Tibiae were quantitatively assessed with microPET for 18F-FDG uptake before and sequentially at 1, 3, and 6 weeks after surgery. Tracer uptake was assessed in soft tissue and bone in both treatment groups with an additional comparison between the operated and unoperated limb. MicroPET analysis was combined with radiographic assessment and complementary histology of the tibiae. Results At the first postoperative week, the 18F-FDG uptake in the contaminated implant group was significantly higher than the preoperative measurement, without a significant difference between the contaminated and uncontaminated tibiae. From the third postoperative week onward, 18F-FDG uptake allowed discrimination between osteomyelitis and postoperative aseptic bone healing, as well as quantification of the infection at distinct locations around the implant. Interpretation 18F-FDG-based microPET imaging allows differentiation between deep infection and undisturbed wound healing after implantation of a titanium intramedullary nail in this rabbit model. Furthermore, our results indicate that 18F-FDG PET may provide a tool in human clinical diagnostics and for the evaluation of antimicrobial strategies in animal models of orthopedic implant infection. PMID:24673540

  1. Effectiveness of FDG-PET/CT for evaluating early response to induction chemotherapy in head and neck squamous cell carcinoma

    PubMed Central

    dos Anjos, Renata Fockink; dos Anjos, Dalton Alexandre; Vieira, Danielle Leal; Leite, André Ferreira; Figueiredo, Paulo Tadeu de Souza; de Melo, Nilce Santos

    2016-01-01

    Abstract Background: 18F-Fluoro-Deoxy-Glucose Positron Emission Tomography with Computed Tomography (18F-FDG PET/CT) may be a powerful tool to predict treatment outcome. We aimed to review the effectiveness of 18F-FDG PET/CT in the assessment of early response to induction chemotherapy (IC) in patients with advanced Head and Neck Squamous Cell Cancer (HNSCC) without previous treatment. Methods: PubMed, Cochrane Library, Science Direct and Web of Science were searched to May 2016. Reference lists of the included articles and additional studies identified by one nuclear medicine expert were screened for potential relevant studies that investigated the effectiveness of 18F-FDG PET/CT performed before and after IC. Three authors independently screened all retrieved articles, selected studies that met inclusion criteria and extracted data. The methodology of the selected studies was evaluated by using the risk of bias checklist of the Agency for Healthcare Research and Quality (AHRQ). Results: Seven out of 170 eligible studies met our inclusion criteria. A total of 207 advanced HNSCC patients were evaluated with 18F-FDG PET/CT at baseline and after IC in the selected articles. Six from seven studies concluded that 18F-FDG PET/CT allowed early evaluation response to IC and predicted survival outcomes. Conclusion: The present systematic review confirms the potential value of 18F-FDG PET/CT as a diagnostic tool for early IV response assessment in HNSCC patients. However, the lack of standard definitions for response criteria and heterogeneous IC protocols indicate the need to further studies in order to better define the role of 18F-FDG PET/CT in these patients. PMID:27512861

  2. Changes of Brain Glucose Metabolism in the Pretreatment Patients with Non-Small Cell Lung Cancer: A Retrospective PET/CT Study

    PubMed Central

    Zhang, Weishan; Ning, Ning; Li, Xianjun; Niu, Gang; Bai, Lijun; Guo, Youmin; Yang, Jian

    2016-01-01

    Objective The tumor-to-brain communication has been emphasized by recent converging evidences. This study aimed to compare the difference of brain glucose metabolism between patients with non-small cell lung cancer (NSCLC) and control subjects. Methods NSCLC patients prior to oncotherapy and control subjects without malignancy confirmed by 6 months follow-up were collected and underwent the resting state 18F-fluoro-D-glucose (FDG) PET/CT. Normalized FDG metabolism was calculated by a signal intensity ratio of each brain region to whole brain. Brain glucose metabolism was compared between NSCLC patients and control group using two samples t-test and multivariate test by statistical parametric maps (SPM) software. Results Compared with the control subjects (n = 76), both brain glucose hyper- and hypometabolism regions with significant statistical differences (P<0.01) were found in the NSCLC patients (n = 83). The hypermetabolism regions (bilateral insula, putamen, pallidum, thalamus, hippocampus and amygdala, the right side of cerebellum, orbital part of right inferior frontal gyrus and vermis) were component parts of visceral to brain signal transduction pathways, and the hypometabolism regions (the left superior parietal lobule, bilateral inferior parietal lobule and left fusiform gyrus) lied in dorsal attention network and visuospatial function areas. Conclusions The changes of brain glucose metabolism exist in NSCLC patients prior to oncotherapy, which might be attributed to lung-cancer related visceral sympathetic activation and decrease of dorsal attention network function. PMID:27529342

  3. Association of Esophageal Inflammation, Obesity and Gastroesophageal Reflux Disease: From FDG PET/CT Perspective

    PubMed Central

    Lee, Yi-Chia; Wang, Shan-Ying; Chiu, Han-Mo; Tu, Chia-Hung; Wang, Hsiu-Po; Lin, Jaw-Town; Wu, Ming-Shiang; Yang, Wei-Shiung

    2014-01-01

    Objective Gastroesophageal reflux disease (GERD) is associated with bothersome symptoms and neoplastic progression into Barrett's esophagus and esophageal adenocarcinoma. We aim to determine the correlation between GERD, esophageal inflammation and obesity with 18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). Methods We studied 458 subjects who underwent a comprehensive health check-up, which included an upper gastrointestinal endoscopy, FDG PET/CT and complete anthropometric measures. GERD symptoms were evaluated with Reflux Disease Questionnaire. Endoscopically erosive esophagitis was scored using the Los Angeles classification system. Inflammatory activity, represented by standardized uptake values (SUVmax) of FDG at pre-determined locations of esophagus, stomach and duodenum, were compared. Association between erosive esophagitis, FDG activity and anthropometric evaluation, including body mass index (BMI), waist circumference, visceral and subcutaneous adipose tissue volumes were analyzed. Results Subjects with erosive esophagitis (n = 178, 38.9%) had significantly higher SUVmax at middle esophagus (2.69±0.74 vs. 2.41±0.57, P<.001) and esophagogastric junction (3.10±0.89 vs. 2.38±0.57, P<.001), marginally higher at upper esophageal sphincter (2.29±0.42 vs. 2.21±0.48, P = .062), but not in stomach or duodenum. The severity of erosive esophagitis correlated with SUVmax and subjects with Barrett's esophagus had the highest SUVmax at middle esophagus and esophagogastric junction. Heartburn positively correlated with higher SUVmax at middle oesophagus (r = .262, P = .003). Using multivariate regression analyses, age (P = .027), total cholesterol level (P = .003), alcohol drinking (P = .03), subcutaneous adipose tissue (P<.001), BMI (P<.001) and waist circumference (P<.001) were independently associated with higher SUVmax at respective esophageal locations. Conclusions Esophageal inflammation

  4. Comparison of Whole-Body (18)F FDG PET/MR Imaging and Whole-Body (18)F FDG PET/CT in Terms of Lesion Detection and Radiation Dose in Patients with Breast Cancer.

    PubMed

    Melsaether, Amy N; Raad, Roy A; Pujara, Akshat C; Ponzo, Fabio D; Pysarenko, Kristine M; Jhaveri, Komal; Babb, James S; Sigmund, Eric E; Kim, Sungheon G; Moy, Linda A

    2016-10-01

    Purpose To compare fluorine 18 ((18)F) fluorodeoxyglucose (FDG) combined positron emission tomography (PET) and magnetic resonance (MR) imaging with (18)F FDG combined PET and computed tomography (CT) in terms of organ-specific metastatic lesion detection and radiation dose in patients with breast cancer. Materials and Methods From July 2012 to October 2013, this institutional review board-approved HIPAA-compliant prospective study included 51 patients with breast cancer (50 women; mean age, 56 years; range, 32-76 years; one man; aged 70 years) who completed PET/MR imaging with diffusion-weighted and contrast material-enhanced sequences after unenhanced PET/CT. Written informed consent for study participation was obtained. Two independent readers for each modality recorded site and number of lesions. Imaging and clinical follow-up, with consensus in two cases, served as the reference standard. Results There were 242 distant metastatic lesions in 30 patients, 18 breast cancers in 17 patients, and 19 positive axillary nodes in eight patients. On a per-patient basis, PET/MR imaging with diffusion-weighted and contrast-enhanced sequences depicted distant (30 of 30 [100%] for readers 1 and 2) and axillary (eight of eight [100%] for reader 1, seven of eight [88%] for reader 2) metastatic disease at rates similar to those of unenhanced PET/CT (distant metastatic disease: 28 of 29 [96%] for readers 3 and 4, P = .50; axillary metastatic disease: seven of eight [88%] for readers 3 and 4, P > .99) and outperformed PET/CT in the detection of breast cancer (17 of 17 [100%] for readers 1 and 2 vs 11 of 17 [65%] for reader 3 and 10 of 17 [59%] for reader 4; P < .001). PET/MR imaging showed increased sensitivity for liver (40 of 40 [100%] for reader 1 and 32 of 40 [80%] for reader 2 vs 30 of 40 [75%] for reader 3 and 28 of 40 [70%] for reader 4; P < .001) and bone (105 of 107 [98%] for reader 1 and 102 of 107 [95%] for reader 2 vs 106 of 107 [99%] for reader 3 and 93 of 107 [87

  5. Comparison of Whole-Body 18F FDG PET/MR Imaging and Whole-Body 18F FDG PET/CT in Terms of Lesion Detection and Radiation Dose in Patients with Breast Cancer

    PubMed Central

    Melsaether, Amy N.; Raad, Roy A.; Pujara, Akshat C.; Ponzo, Fabio D.; Pysarenko, Kristine M.; Jhaveri, Komal; Babb, James S.; Sigmund, Eric E.; Kim, Sungheon G.; Moy, Linda A.

    2016-01-01

    Purpose To compare fluorine 18 (18F) fluorodeoxyglucose (FDG) combined positron emission tomography (PET) and magnetic resonance (MR) imaging with 18F FDG combined PET and computed tomography (CT) in terms of organ-specific metastatic lesion detection and radiation dose in patients with breast cancer. Materials and Methods From July 2012 to October 2013, this institutional review board–approved HIPAA-compliant prospective study included 51 patients with breast cancer (50 women; mean age, 56 years; range, 32–76 years; one man; aged 70 years) who completed PET/MR imaging with diffusion-weighted and contrast material–enhanced sequences after unenhanced PET/CT. Written informed consent for study participation was obtained. Two independent readers for each modality recorded site and number of lesions. Imaging and clinical follow-up, with consensus in two cases, served as the reference standard. Results There were 242 distant metastatic lesions in 30 patients, 18 breast cancers in 17 patients, and 19 positive axillary nodes in eight patients. On a per-patient basis, PET/MR imaging with diffusion-weighted and contrast-enhanced sequences depicted distant (30 of 30 [100%] for readers 1 and 2) and axillary (eight of eight [100%] for reader 1, seven of eight [88%] for reader 2) metastatic disease at rates similar to those of unenhanced PET/CT (distant metastatic disease: 28 of 29 [96%] for readers 3 and 4, P = .50; axillary metastatic disease: seven of eight [88%] for readers 3 and 4, P > .99) and outperformed PET/CT in the detection of breast cancer (17 of 17 [100%] for readers 1 and 2 vs 11 of 17 [65%] for reader 3 and 10 of 17 [59%] for reader 4; P < .001). PET/MR imaging showed increased sensitivity for liver (40 of 40 [100%] for reader 1 and 32 of 40 [80%] for reader 2 vs 30 of 40 [75%] for reader 3 and 28 of 40 [70%] for reader 4; P < .001) and bone (105 of 107 [98%] for reader 1 and 102 of 107 [95%] for reader 2 vs 106 of 107 [99%] for reader 3 and 93 of 107 [87

  6. [Brain metastases].

    PubMed

    Brennum, Jannick; Kosteljanetz, Michael; Roed, Henrik Michael H

    2002-07-01

    The incidence of symptomatic brain metastases in Denmark is about 3500. In the present review, the aetiology, symptomatology, and diagnostic procedures are described. The main topic is a review of current treatments and the evidence for their efficacy. Treatment of brain metastases rarely cures the patient, the goal is rather to improve the quality of life and prolong survival. Without treatment, the median survival following diagnosis of brain metastases is about one month, with steroid treatment two months, with whole brain irradiation four to six months, and after surgery or stereotactic radiosurgery 10-12 months. A relatively simple treatment scheme based on the number of brain metastases and the overall condition of the patient is provided.

  7. Brain peroxisomes.

    PubMed

    Trompier, D; Vejux, A; Zarrouk, A; Gondcaille, C; Geillon, F; Nury, T; Savary, S; Lizard, G

    2014-03-01

    Peroxisomes are essential organelles in higher eukaryotes as they play a major role in numerous metabolic pathways and redox homeostasis. Some peroxisomal abnormalities, which are often not compatible with life or normal development, were identified in severe demyelinating and neurodegenerative brain diseases. The metabolic roles of peroxisomes, especially in the brain, are described and human brain peroxisomal disorders resulting from a peroxisome biogenesis or a single peroxisomal enzyme defect are listed. The brain abnormalities encountered in these disorders (demyelination, oxidative stress, inflammation, cell death, neuronal migration, differentiation) are described and their pathogenesis are discussed. Finally, the contribution of peroxisomal dysfunctions to the alterations of brain functions during aging and to the development of Alzheimer's disease is considered.

  8. FDG-PET/CT Imaging Predicts Histopathologic Treatment Responses after Neoadjuvant Therapy in Adult Primary Bone Sarcomas

    DOE PAGES

    Benz, Matthias R.; Czernin, Johannes; Tap, William D.; Eckardt, Jeffrey J.; Seeger, Leanne L.; Allen-Auerbach, Martin S.; Dry, Sarah M.; Phelps, Michael E.; Weber, Wolfgang A.; Eilber, Fritz C.

    2010-01-01

    Purpose . Tmore » he aim of this study was to prospectively evaluate whether FDG-PET allows an accurate assessment of histopathologic response to neoadjuvant treatment in adult patients with primary bone sarcomas. Methods . Twelve consecutive patients with resectable, primary high grade bone sarcomas were enrolled prospectively. FDG-PET/CT imaging was performed prior to the initiation and after completion of neoadjuvant treatment. Imaging findings were correlated with histopathologic response. Results . Histopathologic responders showed significantly more pronounced decreases in tumor FDG-SUVmax from baseline to late follow up than non-responders ( 64 ± 19 % versus 29 ± 30 %, resp.; P = .03 ). Using a 60% decrease in tumor FDG-uptake as a threshold for metabolic response correctly classified 3 of 4 histopathologic responders and 7 of 8 histopathologic non-responders as metabolic responders and non-responders, respectively (sensitivity, 75%; specificity, 88%). Conclusion . These results suggest that changes in FDG-SUVmax at the end of neoadjuvant treatment can identify histopathologic responders and non-responders in adult primary bone sarcoma patients.« less

  9. Impacts of small arteriovenous malformations (AVM) on regional cerebral blood flow and glucose metabolism

    SciTech Connect

    Liu, R.S.; Yeh, S.H.; Chu, L.S.

    1994-05-01

    This study assessed the effects of small AVMs (<3 cm) on the regional cerebral blood flow (rCBF) by Tc-99m HMPAO SPECT and on the glucose metabolism (rCGlcM) by [F-18]-FDG PET. Seven AVM patients (pts) were studied. All AVMs were confirmed by cerebral angiography and CT/MR scans. Tc-99m HMPAO SPECT and [F-18]-PDG PET images were interpreted visually to detect the changes of rCBF and rCGlcM. All pts except one brain stem AVM had defects in the regions of nidi on HMPAO and FDG images. FDG PET disclosed low rCGlcM in surrounding areas of AVMs in 6 pts, while HMPAO SPECT detected only 4 cases. One AVM had increased rCBF surrounding the nidus despite of decreased rCGlcM in the same region. Five pts had abnormal rCGlcM over ipsilateral remote cortex but only one had corresponding abnormal rCBF. Contralateral cortical hypofunction was noted in 3 pts by FDG PET but none by HMPAO SPECT. Cross cerebellar diaschisis was found in 2 AVMs by FDG PET and only one by HMPAO SPECT. All regions with abnormal HMPAO uptake did not look as discernibly as seen on the FDG PET scan. CT/MR scans detected the nidi of AVMs of all pts and old hemorrhage in one pt. In conclusion, either HMPAO SPECT or FDG PET is sensitive to detect the functional abnormalities in the region of nidus of small AVM and the surrounding brain tissue. FDG PET is better than HMPAO SPECT to detect functional changes in the remote cortex and diaschisis.

  10. Is there an added clinical value of "true"whole body(18)F-FDG PET/CT imaging in patients with malignant melanoma?

    PubMed

    Tan, Julie C; Chatterton, Barry E

    2012-01-01

    Accurate and reliable staging of disease extent in patients with malignant MM is essential to ensure appropriate treatment planning. The detection of recurrent or residual malignancy after primary treatment is important to allow for early intervention and to optimise patient survival. 2-deoxy-2-[(18)F]fluoro-D-glucose ((18)F-FDG) PET or PET computed tomography (PET/CT) is indicated for surveillance of malignant MM due to its high sensitivity and specificity for soft-tissue or nodal recurrences and metastases. It has been claimed that including lower extremities and skull in addition to 'eyes to thigh' images in PET/CT evaluation of metastatic MM routinely is warranted. We have studied retrospectively the reports of whole-body PET/CT scans in all patients with MM scanned in our Department from April 2005 to December 2010. All PET abnormalities in the brain/scalp and lower extremities were tabulated by location and whether they were 'expected' or 'unexpected'. Findings were correlated with pathology, other imaging studies, and clinical follow-up. In this study, 398 PET/CT examinations in 361 patients with MM were included. Results showed that twelve of the 398 (3%) scans had brain/scalp abnormalities, with only 4 (1.0%) showing unexpected abnormalities. Twenty nine of the 398 (7.2%) scans showed lower extremity abnormalities, with only 5 (1.2%) showing unexpected abnormalities. In no case was an isolated unexpected malignant lesion identified in the brain/scalp or lower extremities. In conclusion, whole body PET/CT scan showed about 1% unexpected primary or metastatic MM lesions involving the head or lower extremities, which seldom offered significant additional clinical benefit and were unlikely to change clinical management. No clinically significant change in staging would have occurred. Routine 'eyes to thighs' images were adequate for this subset of patients. PMID:23106051

  11. Characterization of brown adipose tissue ¹⁸F-FDG uptake in PET/CT imaging and its influencing factors in the Chinese population.

    PubMed

    Shao, Xiaonan; Shao, Xiaoliang; Wang, Xiaosong; Wang, Yuetao

    2016-01-01

    (18)F-FDG PET/CT has been widely applied for tumor imaging. However, it is reported that many normal tissues, e.g., brown adipose tissue, can also uptake (18)F-FDG. The purpose of this study was to determine the imaging characteristics of (18)F-FDG uptake in brown adipose tissue (BAT) in PET/CT. A total of 2,944 patients who underwent PET/CT from September 2011 to March 2013 were analyzed retrospectively. Imaging features of (18)F-FDG uptake in BAT were analyzed. Univariate analysis and logistic regression analysis were performed to evaluate the effect of age, gender, cancer status, body mass index (BMI), average daily maximum temperature of imaging month and fasting plasma glucose (Glu) on the positive rate of (18)F-FDG uptake in BAT. The results showed that 1.9% (57/2944) patients had (18)F-FDG uptake in BAT. (18)F-FDG, manifested as flaky, nodular and beaded shape, was symmetrically distributed in the adipose tissues of cervical and supraclavicular, mediastinal, paravertebral, and perirenal areas. Uptake of (18)F-FDG within cervical/supraclavicular area was most common (89.5%, 51/57) with an SUVmax ranging from 2.8 to 31.4. Univariate analysis showed that gender and cancer status were not significantly correlated with the BAT (18)F-FDG uptake rate. In contrast, age, BMI, Glu and average daily maximum temperature in the imaging month were significantly correlated with the BAT (18)F-FDG uptake rate (P<0.05). Further logistic regression analysis showed that only age, BMI and average daily maximum temperature were significant (OR<1, P<0.05). Based on the value of OR, the most significant factor that affects BAT (18)F-FDG uptake rate was age, followed by the average daily maximum temperature and BMI. We concluded that Chinese adult has low positive rate of (18)F-FDG uptake in BAT. Cervical/Supraclavicular is the most common area with BAT (18)F-FDG uptake. Age, average daily maximum temperature and BMI are independent factors affecting (18)F-FDG uptake. PMID:26702781

  12. Characterization of brown adipose tissue ¹⁸F-FDG uptake in PET/CT imaging and its influencing factors in the Chinese population.

    PubMed

    Shao, Xiaonan; Shao, Xiaoliang; Wang, Xiaosong; Wang, Yuetao

    2016-01-01

    (18)F-FDG PET/CT has been widely applied for tumor imaging. However, it is reported that many normal tissues, e.g., brown adipose tissue, can also uptake (18)F-FDG. The purpose of this study was to determine the imaging characteristics of (18)F-FDG uptake in brown adipose tissue (BAT) in PET/CT. A total of 2,944 patients who underwent PET/CT from September 2011 to March 2013 were analyzed retrospectively. Imaging features of (18)F-FDG uptake in BAT were analyzed. Univariate analysis and logistic regression analysis were performed to evaluate the effect of age, gender, cancer status, body mass index (BMI), average daily maximum temperature of imaging month and fasting plasma glucose (Glu) on the positive rate of (18)F-FDG uptake in BAT. The results showed that 1.9% (57/2944) patients had (18)F-FDG uptake in BAT. (18)F-FDG, manifested as flaky, nodular and beaded shape, was symmetrically distributed in the adipose tissues of cervical and supraclavicular, mediastinal, paravertebral, and perirenal areas. Uptake of (18)F-FDG within cervical/supraclavicular area was most common (89.5%, 51/57) with an SUVmax ranging from 2.8 to 31.4. Univariate analysis showed that gender and cancer status were not significantly correlated with the BAT (18)F-FDG uptake rate. In contrast, age, BMI, Glu and average daily maximum temperature in the imaging month were significantly correlated with the BAT (18)F-FDG uptake rate (P<0.05). Further logistic regression analysis showed that only age, BMI and average daily maximum temperature were significant (OR<1, P<0.05). Based on the value of OR, the most significant factor that affects BAT (18)F-FDG uptake rate was age, followed by the average daily maximum temperature and BMI. We concluded that Chinese adult has low positive rate of (18)F-FDG uptake in BAT. Cervical/Supraclavicular is the most common area with BAT (18)F-FDG uptake. Age, average daily maximum temperature and BMI are independent factors affecting (18)F-FDG uptake.

  13. (18)F-FDG-PET/CT and (18)F-NaF-PET/CT in men with castrate-resistant prostate cancer.

    PubMed

    Zukotynski, Katherine A; Kim, Chun K; Gerbaudo, Victor H; Hainer, Jon; Taplin, Mary-Ellen; Kantoff, Philip; den Abbeele, Annick D Van; Seltzer, Steven; Sweeney, Christopher J

    2015-01-01

    To evaluate (18)F-labeled-fluorodeoxyglucose ((18)F-FDG-) and (18)F-labeled-sodium fluoride ((18)F-NaF-) positron emission tomography/computed tomography (PET/CT) as biomarkers in metastatic castrate-resistant prostate cancer (mCRPC). Nine men (53-75 years) in a phase 1 trial of abiraterone and cabozantinib had (18)F-FDG-PET/CT, (18)F-NaF-PET/CT and standard imaging ((99m)Tc-labeled-methylene-diphosphonate ((99m)Tc-MDP) bone scan and abdominal/pelvic CT) at baseline and after 8 weeks of therapy. Baseline disease was classified as widespread (18)F-FDG-avid, oligometastatic (18)F-FDG-avid (1 site), or non-(18)F-FDG-avid. Metabolic response was classified using European Organisation for Research and Treatment of Cancer (EORTC) criteria. Treatment response using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, Prostate Cancer Working Group 2 (PCWG2) guidelines and days on trial (DOT) were recorded. All men were followed for 1 year or until progression. Four men had (18)F-FDG-avid disease: two with widespread (DOT 53 and 76) and two with oligometastatic disease (DOT 231 and still on trial after 742+ days). Five men had non-(18)F-FDG-avid disease; three remained stable or improved (2 still on trial while one discontinued for non-oncologic reasons; DOT 225-563+), and 2 progressed (DOT 285 and 532). Despite the small sample size, Kaplan-Meier analysis showed a significant difference in progression free survival (PFS) between men with widespread (18)F-FDG-avid, oligometastatic (18)F-FDG-avid and non-(18)F-FDG-avid disease (p < 0.01). All men had (18)F-NaF-avid disease. Neither (18)F-NaF-avid disease extent nor intensity was predictive of treatment response. (18)F-FDG-PET/CT may be superior to (18)F-NaF-PET/CT and standard imaging in men with mCRPC on abiraterone and cabozantinib. (18)F-FDG-PET/CT may have potential to stratify men into 3 groups (widespread vs. oligometastatic (18)F-FDG-avid vs. non-(18)F-FDG-avid mCRPC) to tailor therapy. Further evaluation is

  14. Is it practical and cost effective to detect differentiated thyroid carcinoma metastases by (18)F-FDG PET/CT, by (18)F-FDG SPET/CT or by (131)I SPET/CT?

    PubMed

    He, Xinjia; Wang, Xucai; Yu, Jinming; Ma, Chao

    2015-01-01

    Fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography/computerized tomography ((18)F-FDG PET/CT) plays an important role in detecting differentiated thyroid carcinoma (DTC) metastases with elevated thyroglobulin (Tg) and negative radioiodine ((131)I) uptake. In conclusion, (18)F-FDG PET/CT may fail to detect all DTC metastases, while (131)I WBS combined with (131)I SPET/CT may be a better cheaper and diagnostic tool as suggested by the case we presented here. Positive metastases in both (131)I and (18)F-FDG SPET/CT may indicate worse prognosis. Future research may add more evidence as to which is the best diagnostic imaging modality and relate it to the molecular mechanism of the uptake of the radionuclide used.

  15. Brain investigation and brain conceptualization

    PubMed Central

    Redolfi, Alberto; Bosco, Paolo; Manset, David; Frisoni, Giovanni B.

    Summary The brain of a patient with Alzheimer’s disease (AD) undergoes changes starting many years before the development of the first clinical symptoms. The recent availability of large prospective datasets makes it possible to create sophisticated brain models of healthy subjects and patients with AD, showing pathophysiological changes occurring over time. However, these models are still inadequate; representations are mainly single-scale and they do not account for the complexity and interdependence of brain changes. Brain